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GOODY E A R A E R O S P A C E CORPORATION

A K R O N 15. OHIO

Copy No. - S T A T E - O F - T H E - A R T STUDY FOR

HIGH-SPEED DECELERATION AND

STABILIZATION DEVICES

G E R - 12616 10 S e p t e m b e r 1966

W i l l i a m C . A l e x a n d e r R i c h a r d A. L a u

Goodyea r A e r o s p a c e C o r p o r a t i o n , A k r o n , Ohio

f o r

Nat ional A e r o n a u t i c s a n d S p a c e A d m i n i s t r a t i o n

Washington , D. C.

REPRODUCED B Y NATIONAL TECHNICAL INFORMATION SERVICE

U.S. DEPARTMENT OF COMMERCE SPRINGFIELD. VA. 22161

https://ntrs.nasa.gov/search.jsp?R=19660027566 2018-06-03T04:23:42+00:00Z

ABSTRACT

Documented aerodynamic deployable decelerator per - formance data above Mach 1. 0 is presented. The s tate

of the a r t of drag and stability character is t ics for r e -

entry and recovery applications i s defined for a wide

range of decelerator configurations. Structural and m a -

t e r i a l data and other design information also a r e p re -

sented. Emphasis i s given to presentation of bas ic aero,

thermal , and s t ruc tura l design data, which points out

bas ic problem a r e a s and voids in existing technology.

The bas ic problems and voids include supersonic "buzz-

ing" of towed porous decelerators in the wake of the forebody,

the complete lack of dynamic stability data, and the gen-

e r a l lack of aero thermal data at speeds above Mach 5. ,i'

G E R - 12616

SUMMARY

Available documented superson ic and hypersonic data ( thermodynamic, strut:-

t u r e s , and m a t e r i a l s ) have been surveyed and s u m m a r i z e d to indicate the

s ta te of the a r t of dece le ra t ion and s tabi l iza t ion devices .

Supersonic pa rachu tes that have been success fu l ly flight t e s t ed indicate a

pe r fo rmance l imi t of approx imate ly Mach 3 . Although parachu tes have p e r -

f o rmed between Mach 3 and 6 i n i sola ted t e s t s , which demons t r a t e s f e a s ib i l i l : ~ ,

the conclusion cannot be made that they can p e r f o r m sa t i s fac to r i ly throughout

the superson ic Mach number range during dece le ra t ion . During wind tunnel

t e s t s , a l l parachutes exper ienced some canopy breathing, even behind payload

bodies of revolution, while operat ing above Mach 2 . 5. Until a bas ic a e rody -

namic superson ic in le t p rob lem, which i s f u r t h e r compl icated by the payload

complex wake, i s solved, the possibil i ty of success fu l pa rachu te operat ion a1.

high Mach numbers (above superson ic speed) a p p e a r s r e m o t e .

Inflatable dece l e r a to r s up to f ive feet in d i ame te r have been successful ly flight

t e s ted up to approx imate ly Mach 3 . 8 and dynamic p r e s s u r e s up to approxi-

ma t e ly 200 psf . Metal cloth dece l e r a to r s have been t es ted i n the wind tunnel

up to Mach 10 and f ab r i c mode ls up to Mach 6 . These nonporous, nea r l y g a s -

t ighttowed dece l e r a to r s w e r e found to be the l e a s t sens i t ive to a forebody wake

and t he r e fo r e pe r fo rmed in a s table and sa t i s fac to ry m a n n e r .

Mate r ia l s development p r o g r a m s have resu l t ed in finding l ighter weight nylon

and Nomex woven cloths and webbing f o r a given s t r u c t u r a l s t reng th . Flexible

coatings a l s o have been developed that not only p ro tec t the dece l e r a to r s f ro r r

heat but a l s o make a dece l e r a to r gas tight a t a m in imum of weight. Woven

s t randed w i r e m e t a l a l s o ha s been developed. L a r g e gaps ex i s t i n the oper -

a t ional t empe ra tu r e ranges due to the l ack of proved m a t e r i a l s . Higher-

s t reng th , m o r e f lexible cloths a r e s t i l l needed a s wel l a s h igher t empe ra tu r e

impe rmeab l e coatings.

SUMMARY GER-12616

There i s very little experimental o r analytical aerodynamic, thermodynamic,

o r s t ruc tura l data available in the supersonic and hypersonic speed range. A

general lack of analytical methods exists to descr ibe basic phenomena, includ-

ing lack of aerodynamic data over a range of Reynolds numbers; a complete

lack of quantitative experimental dynamic stabili ty data; and a basic lack of

understanding of a forebody wake flow when influenced by a towed d e c e l e r a t o ~ .

- iv-

FOREWORD

This r epo r t was p repared by Goodyear Aerospace Corporat ion,

Akron, Ohio, under Contract NASW- 1288 and under the cogni-

zance of J. E. Greene , Off ice of Advanced R e s e a r c h and Tech-

nology (OART), NASA Headquar te r s , Washington, Do C.

J. T . McShera, J r . , Fu l l Scale Divsion, NASA Langley Sta-

tion, Hampton, V a . , s e rved a s con t rac t technical moni to r .

P ro j ec t engineer was W. C. Alexander ; a s s i s t an t p ro jec t engi-

neer was R. A. Lau - both f r o m Goodyear Aerospace . Other

contributing personnel f r o m Goodyear Aerospace w e r e F. R.

Nebiker, manage r , Recovery Sys tems Engineering; W. V.

Arnold, a s s i s t an t manager , Recovery Sys tems Engineer ing;

F. Bloe t scher , consultant; I. M. Ja remenko , aerodynamic

wakes; H. H. Shee te r , aerodynamic stabil i ty; W. W . Sowa,

thermodynamics; J. F. Werne r , s t r u c t u r e s ; and P. F. Myer s ,

ma te r i a l s . The data gathering cut-off date was 1 Apr i l 1966.

GER- 12616

TABLE O F CONTENTS

SUMMARY . . . . . . . . . . . . . . . . . . . . . . . .

. . . . . . . . . . . . . . . . . . . . . . . FOREWORD.

LIST O F ILLUSTRATIONS. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . LIST O F TABLES

Section Ti t l e

I INTRODUCTION . . . . . . 1. Genera l . . . . . . . . . . . . . . . . . .

a . P r o g r a m Objective . . . . . . . . . . . - . . . b. Background and P rob l em S ta t emen t . - . . . . . . . . . c . S c o p e a n d c o n s t r a i n t s . - . . . . . . . . . . d. Descr ipt ion of Sea rch -

e . His to r ica l Summary . . . . . . . . . . -

I1 STATE O F THE ART O F AERODYNAMIC DEPLOY- ABLEDECELERATORS. . . . . . . . . . . . . 1. Genera l . . . . . . . . . . . . . . . . . .

. . . . 2 . Design and Pe r fo rmance Requirements

3 . Design Concepts . . . . . . . . . . . . . . 4. Aerodynamics . . . . . . . . . . . . . . .

. . . . . . . . . . . . . . . . a . Genera l - b. Steady-State Drag of Towed Porous Decel- -

e r a t o r s . . . . . . . . . . . . . . . c . Steady-State Drag of Towed Nonporous De- -

c e l e r a t o r s . . . . . . . . . . . . . . . . . . . d. Attached Nonporous Dece l e r a to r s - . . . . . e . T rans i en t and Fluctuating Loads -

. . . . . . . . . . . 5. Aerodynamic Stabi l i ty . . . . . . . . . . . . . . . . . . a . Gene ra l - . . . . . . b. Attached Dece le ra to r Sys tem -

c . Towed ~ e ' c e l e r a t o r S y s t e m . . . . . . . . - d. Wake Effect on the Dece l e r a to r . . . . . . -

1 Preceding page blank

P a g e

iii

TABLEOFCONTENTS GER-12616

Section Title

6 . Aerothermodynamic Loading . . . . . . . . a . General . . . . . . . . . . . . . . . . b . Equations . . . . . . . . . . . . . . . Structures . . . . . . . . . . . . . . . . a . General . . . . . . . . . . . . . . . . . b . Ballute and Spheres . . . . . . . . . . . - c . Parachutes . . . . a . 0 . . . . . . . - d . Airmat Cone . . . . . . . . . . . . . . - e . Inflated Skir ts ( F l a r e s ) . . . . . . . . . - f . Tension Shells . . . . . . . . . . . . . -

8. Materials . . . . . . . . . . . . . . . . . a . General . . . . . . . . . . . . . . . . - b . Textile Yarns and Fibers . . . . . . . . - c . Filament Materials . . . . . . . . . . . - d . Woven Fabric Materials . . . . . a . a . - e . F a b r i c c o a t i n g s . . . . . . . . . . . . - f . Joining Methods . . . . . . . . a . . q - . . . g . Material Selection and Qualification h . Current Development in Materials . . . . - i . Future Development in Materials . . . . . -

DESIGN DISCUSSION . . . . . . . . . . . . . . 1 . System Designs and Logis tics Sequencing

. . . . . . . . . . . . . . . . . . Methods

2 . Design Procedures and Cr i te r ia . . . . . . . a . General . . . . . . . . . . . . . . . . - b . Pre l iminary Design Procedure for Super- -

sonic Decelerator . . . . . . . . . . . c . Available Design Data for Dynamic Deploy- -

ment Loads . . . . . . . . . . . . . . DATACONFIDENCE . . . . . . . . . . . . . . 1 . General . . . . . . . . . . . . . . . . . . 2 . Similarity Cr i te r ia . . . . . . . . . . . . . 3 . Flexibility and Strength . . . . . . . . . . .

. . . . . . . . . . . . . . . 4 Surface Texture

5 . Dynamics . . . . . . . . . . . . . . . . .

PRESENT HIGH-SPEED RECOVERY TECHNIQUES. . . . . . . . . . PROBLEM AREAS. AND VOIDS

1 . General . . . . . . . . . . . . . . . . . .

Page

TABLE O F CONTENTS GER-12616

Section Ti t l e

2. Pe r fo rmance Limi t s . a . + . *

3. S t ruc tu r e s and Mater ia l s , ~

4. P rob l em A r e a s and Voids . . a . . a . .

CONCLUSIONS . . . . . . . . 1. Gene ra l . . . . . . . . . . . . . . . . . . 2. Aerodynamics . . . . . . . . a . . . 3 . St ruc tu re s and Mater ia l s , . . . . . . . .

LIST O F SYMBOLS . . . . . . . . . . . . . . . . . . . . LIST O F REFERENCES . . . . . . . . . . . . . . . . . . Appendix

A BIBLIOGRAPHY . . . . . . . . . . . . . . . .

Page

179

182

184

F i g u r e

1

2

3

4

5

6

LIST O F ILLUSTRATIONS

Ti t le

Study Spec t rum . . . . . . . . . . . T h e r m a l Pe r fo rmance Spec t rum . . . . . . . . Decele ra to r Configurations . . . . . . . .

Miscel laneous Dece le ra to r Concepts . . a . . *

Coefficient of Drag v s Mach Number . . . . A r e a Ratio v s Mach Number f o r L a r g e Supersonic Pa rachu t e s . . . . . . . a . . . . . . CD vs A r e a Rat io f o r L a r g e Supersonic Parachutes ,

Wind-Tunnel Tes t ed C v s Mach Number fo r Hyperflo D Pa rachu t e s . . . . , , , . . a . . . . . . , .

Guide-Surface Parachute CD vs x/d . . . . . C

Guide-Surface Parachute C vs Mach Number a t Dc One Towed Condition (with Minimum C Variat ion) .

D

C vs Mach Number fo r Large-S ize Ballutes D

C vs Mach Number fo r Small-Size Wind-Tunnel T e s t D

B a l l u t e s . . . . . . . . a

C vs Mach Number for 80-Deg Cone . . , D

CD vs x/d fo r 80-Deg Rigid Cone. . . . . F r e e - S t r e a m Cone Data v s Mach Number . . . .

Axial Nose Drag Coefficient v s Mach Number a . .

Sphere CD v s Mach Number (8-In. Model) . . a a . . Sphere C v s Mach Number (4-In. Model ) . . . . .

D

Page

6

8

10

3 3

37

, Preceding page blank

LIST OF ILLUSTRATIONS GER-12616

Figure

19

20

Title Page

CD vs Mach Number for Sphere behind F la red Body . 62

C vs Mach Number for Sphere behind Cylindrical D

Body . . . . . . . . . . . . . . . . . . . . . .

C vs Mach-Number for Spheres at Various High D

Reynolds Numbers . . . . . . . . . . . . . . . .

Correlation of Sphere Drag Coefficients. . . . . . .

CD vs Bs for F la red Body . . . . . . . . . . . .

5 . 5 - F t Do Parasonic (Oscillograph - Instantaneous

Load vs Time); See Table XI, Item 14. a . 0 . . .

5. 5-Ft D Parasonic (Instantaneous C vs Time); 0 D

See Table XI, Item 1 4 . . . . . O. - . . . . .

4-F t Do Hyperflo (Instantaneous CD vs Time); See 0 Table XI, Item 9 . . . . . . . . . . . . . . . . .

3 - F t Diameter Ballute, Load vs Time (See Table XI, I tem 7) . . . . . . . . . . . . . . . . . . . . .

C vs Mach Number for Cones. . . * * N

cp vs Mach Number for Cones . . . . . . . . . . a

Drag vs x/d, Hyperflo Model 1 behind Forebody Type I

Drag vs x/d, Hyperflo Model 1 behind Forebody Types . . . . . . . . . . . . . . . . . . . . . I and I1

Drag vs Mach Number, Hyperflo Model 2 behind F o r e - body Type I . . . . . . . . . . . . . . . . . . .

Heat Flux and Temperature Distribution on a Sphere Laminar Flow . . . . . . . . . . . . . . . . . .

Heat Flux and Temperature Distribution on a Sphere Turbulent F low. , * . a . . a

Laminar Heat Flux and Temperature Distribution on a . . . . . . . . . . . . . . . . . . Blunted Cone.

LIST O F ILLUSTRATIONS GER-12616

F igu re

3 6

Ti t le

Turbulent Heat F lux and Tempera tu r e Distr ibution on a . . . . . . . . . . . . . . . . . . . . Blunted Cone

. . . . . . . . Mach 10 Ballute Heat - T r a n s f e r Resul ts

. . . . . . . . . . . . . . Parachute Configuration

4 -F t Diameter Dece le ra to rs To Be Flight Tes ted a t Mach 5 . . . . . . . . . . . . . . . . . . . . . .

. . . . . . Coated Metal.-Cloth, 5 - F t Diamete r Ballute

Sketches of Sphere. Parachute . BalPute. and F l a r e . . . . . . . . . . . . . . 4-F t D Pa ra son i c Pa rachu t e

0

. . TB 1 Ballute Configuration . . . . . . . . . . . . . . . . . . . . . . . . . Ballute Weight v s Radius

. . . . . . . . . . . . . . Airrnat Cone Dimensions

. . . . . . . . . . 80-Deg Ai rmat Cone (Pre inf la ted)

Ai rmat Cone Weight v s Radius fo r Various Values of q

. . . . . . . Tension Shell Loading System. Assumed

Typical S t r e s s -Stra.in Curves fo r Dacron, Nylon. and . . . . . . . . . . . . . . . . . . . . . . Nomex

Strength Retained by Nylon. Dacron. and Nornex Yarns . . . . . . . . . . . af te r Exposure to Hot. Dry Air

Breaking Tenacity a t Various Tempera tu r e s . . . . . Shrinkage of Nylon. Dacron. and Nomex Exposed to Hot. Dry Air . . . . . . . . . . . . . . . . . . . . . . Variation of Tensi le Strength and Elongation of Nylon F i b e r s I r r ad i a t ed i n Nitrogen a t 244 m p . 3 14 mu. and 369 mp . . . . . . . . . . . . . . . . . . . . . . Variation of Tensi le P r o p e r t i e s with Incident Energy f o r Dacron I r r ad i a t ed i n Nitrogen with A-H6 L a m p

Page

LIST OF ILLUSTRATIONS GER- 126 16

Figure Title

55 Variation of Tensile Strength and Ultimate Elongation of Nomex Irradiated i n Nitrogen with Ultraviolet Light and with Visible Light (437 mu) . . . . a . . . Degradation of Nomex af te r Exposure to Ultraviolet Radiation and Elevated Tempera tures . . . . . . . Effects of Gamma Radiation on Nomex a t 400 F (Top) and a t 600 F (Bottom) . . . . . . . . . . . a . . Comparisons of Nylon and Nornex af ter Outdoor Ex- posure (Top) and af ter Accelerated Weathering (Bottom). . . . . . . . . . . . . . . . . . . . . High-Temperature Tensile Strength of 1.0-Mil Super- alloy Wires . . . , . . . . . . . . . . . . . . . High-Temperature Tensile Strength of 0. 5 - and 1. 0- Mil Wires a s a Function of Exposure Time . . . . . High-Temperature Tensile Strength of 0.5 -Mil Super- alloy Wires . . . . . . . . . . . . . . . . . . .

/ Creep of 0.5-Mil Rene 41 Wire a t 2000 F (Linear Plot)

Strength-to-Weight Ratio of 1. 0 -Mil Superalloy and Refractory Metal Wires . . . . . . . . . . . a . . Comparison of Strength-Retention Character is t ics of Part ia l ly Carbonized, Carbon, and Graphite Fabr ics . Strength Retention vs Temperature for P resen t and Future F ibe r s . . . . . . . . . . . . . . . . Typical Recovery-System Deployment Sequence . . . Paramete r s Affecting Design of Towed Drag Devices . Ballute CD vs Mach Number (Flight Test Data) . . .

Page

LIST O F TABLES

Table

I

I1

111

IV

v

VII

VIII

X I V

Tit le

R and D - Cone Dece le ra to rs in F r e e S t r e a m . . .

R and D - Towed-Cone Dece le ra to rs , . . . . .

R and D - Sphere Dece le ra to rs in F r e e S t r e a m . . R and D - Towed-Sphere Dece le ra to rs . . . . . . R and D - F r e e - S t r e a m and Towed-Ballute Dece le r - a t o r s . . . . . . . . . . . . . . . . . . . . .

R and D - Flared-Ski r t Dece le ra to rs . . . . . . .

R and D - Hemisflo, Conical, and Standard F la t Ribbon Parachutes . . . . . . . a . . . . . R and D - Hyperflo, Pa r son i c , and Supersonic Guide- Surface Pa rachu t e s . . . * . . , . . . . , , - R and D - Tension-Shell . . . . . . . . ,

Miscellaneous Configurations . , . . , , , . .

Figu re s 6 and 7 Data Point Tes t Conditions . . .

Decele ra to r T e s t Resul ts ~ a a . . . . a . * .

Effects of Environment on Natura l and Manmade Text i les . . . . . . . . , . . . .

Fi lament Diamete rs Required for Flexibil i ty Equi~ra - lent to Nylon and F ibe rg l a s s . . . . . . . . . . Fibe r Tenaci t ies . . . . . . . . . . . . . Radiation Res i s tance : Effect of Exposure on Yarn Strength . . . . . . . . . . . . .

Page

13

15

17

19

LIST O F T A B L E S GER-12616

Table

X VII

X V'III

XIX

Title Page

Relative General Proper t ies of Elas tomers . . . a 157

Elastomeric Coatings . . . . . . . . . . . . . . 159

Sequencing Hardware . . . . . . . . , . 168

GER- 126 16

SECTION I - INTRODUCTION

GENERAL

a . P r o g r a m Objective -

Under Contract NASW - 1288 with the National Aeronaut ics and Space Ad-

minis t ra t ion, Washington, D. @. , Goodyear Aerospace Corporation ha s

conducted a study p r o g r a m of deployable aerodynamic dece l e r a to r s f o r

r e - en t ry and recovery applications f r o m Mach 1 to Mach 25. The ob-

jective of th is p r o g r a m was to survey and s u m m a r i z e available docu-

mented superson ic and hypersonic analyt ical and exper imenta l data to

de te rmine the l a t e s t s t a te of the a r t of decelera t ion and stabil ization de -

v ices . The findings of th is study, presei-ited i n this repor t , s u m m a r i z e

the s ta tus of high -speed recovery techniques and supplement Reference 1

and o ther handbook-type r epo r t s .

b. Background and P rob l em Statement -

With the advent of the space age, and the gene ra l need to provide fo r s u c -

cess fu l en t ry , r e - en t ry , and descent into the a tmosphere of the ea r th and

other p lanets , new and efficient (lightweight, low cos t ) methods of dece l -

e ra t ion and stabil ization m u s t be developed to recover payloads such a s

manned space capsu les , emergency escape capsu les , ins t rument data

packages , rocket boos t e r s , and nose cones . Before such devices can

be developed, additional ba s i c and applied r e s e a r c h will be requ i red .

This study p r o g r a m was conducted to provide data f o r an overa l l " in-

house" NASA evaluation study to de te rmine the s ta te of the a r t of supe r -

sonic dece le ra to r sy s t ems .

c. Scope and Constra ints -

The study was per formed s o s y s t e m design c r i t e r i a could be es tabl ished

SECTION I - INTRODUCTION GER- 126 16

f o r providing supplemental drag a r e a to bes t meet the needs of the follow-

ing supersonic - sample, general-recovery applications:

1. Payload stabilization and deceleration to conditions

necessary for a satisfactory deployment of a final-

stage landing device (conventional parachute, glid-

ing pa.rachute, inflatable wings, paragl iders)

2. Payload r e -entry to minimize temperature and de-

celeration environment

3. Initial high-speed stabilization of spacecraf t o r

booster, o r both

4. Emergency escape f rom any flight vehicle (a i rc raf t ,

space capsule)

5. Highly stable low supersonic descent of ins t ru-

mented payloads operating a t a high altitude in the

atmosphere (high -altitude a i r sampling, infrared

payload tracking)

The performance data fo r these recovery applications include aerody-

namic drag and stability charac ter i s t ics for both steady and unsteady

conditions; performance data fo r both f r e e - s t r e a m operations and oper -

ations in the wake of a forebody; s t ruc tura l and mater ia l design-support

data; and basic aerothermodynamic design parameters and their effect

on the stowage, deployment, and operation of the decelerator . The study-

spectrum l imits were a s follows:

1. Mach number - 1 to 25 (emphasis on Mach 1.5 to

Mach 10)

2. Altitude - below 600, 000 ft (emphasis below

200, 000 f t )

3. Temperature - below 3000 F (emphasis below

1000 F)


d. Description of Search -

The program was initiated with a l ibrary sea rch , during which a bibliog-

raphy of applicable documents ( see Appendix A) was obtained f rom:

1. DDC (Defense Documentation Center)

2. NASA STAR

3 . Goodyear Aerospace Library

F r o m these bibliographies applicable repor ts and other documents were

ordered, and their abs t rac ts , resu l t s , and conclusions were reviewed.

The detailed data presented in this report a r e based on the l i s t of r e fe r -

ences on pages 195 through 201. The bibliography of this report groups

related publications according to the issuing o r authorizing government

agencies and other sources.

e. Historical Summary - The concept of aerodynamic decelerators in the fo rm of parachutes dates

back a t leas t to DaVinci and probably ea r l i e r . Until the balloon flights

of the nineteenth century and the heavier -than-air flights of the twentieth,

parachutes were of little more than scientific interest . World War I dem-

onstrated their practicali ty, as had the ea r l i e r balloon flights, for safe

descent f rom a disabled a i rc raf t . At that t ime, development headed to-

ward the modern smal l packaged canopy and attaching body harness f rom

the noncollapsible canopies and t rapeze o r open-basket containers of the

balloonists. With packaging came the complication of deployment, and

various methods were utilized - stat ic l lnes, pilot chutes, etc. F r o m

1945 to 1955, higher speed (transonic and low supersonic) and higher al t i -

tude (up to 100, 000 f t ) mili tary applications a rose .

Between 1955 and 1960, the space-age ar r ived , bringing with i t s t i l l

higher speed (high supersonic and hypersonic) and higher altitude (o r -

bital and superorbital) applications. The new applications consisted of

recovering al l types of payloads over a broader flight spectrum. Be-

cause of these new recovery requirements , supersonic tes ts were


conducted; the initial formal documented resul ts of these tes t s became

available about 1960, Goodyear Aerospace Corporation's search r e - vealed that, since 1960, the number and type of experimental tes t s were

greatly increased, and most of the available experimental data presented

in this report were generated during this period.

GER- 126 16

SECTION 11 - STATE OF THE ART OF AERODYNAMIC

DEPLOYABLE DECELERATORS

1. GENERAL

This sect ion provides a s u m m a r y and analysis of available data on a e r o -

dynamic dece l e r a to r s that a r e deployable i n the superson ic and hyper -

sonic speed ranges . The var ious dece l e r a to r s a r e categor ized into a e r o -

dynamic shape configurations, Appropr ia te informat ion on design, ae ro- .

dynamic per formance , s t r u c t u r e s and m a t e r i a l s , and logis t ics sequencing

i s presented.

2 . DESIGN AND PERFORMANCE REQUIREMENTS

The scope and l imi ta t ions of dece le ra t ion devices included i n th is study

in t e r m s of the flight r eg ime a r e p resen ted in F igu re 1. This f igure de -

picts the de s i r ed flight - study s p e c t r u m of al t i tude v e r s u s Mach number

f o r gene ra l r e cove ry - sys t em applications. The c ross -ha tched a r e a shows

the ma in emphas i s of th is study.

Since the main function of a deployable dece l e r a to r i s to genera te a s p e -

cific amount of aerodynamic drag f o r dece le ra t ion and stabil ization with

a min imum of weight and bulk, the key design goal i s to obtain a max i -

m u m value of the squa re fee t of d r ag a r e a pe r pound of weight, To p r e -

dict that a given configuration ( a given geomet r ic shape o r a composi te

a r r angemen t of var ious shapes ) wi l l obtain ce r t a in values of d rag a r e a

and hence wi l l p e r f o r m i n a p r e sc r ibed manne r , the effects of h igh-speed

aero thermodynamics and space mechanics per formance p a r a m e t e r s m u s t

be known and understood.

The deployment of a dece l e r a to r during a r e - en t ry o r recovery operation

leads to an i n c r e a s e i n the d r ag f o r c e s acting on the vehicle sy s t em. As

300

250

200

150

- + W Id

LL 100 lL 0 (0

0 z Q (0 3 0 I 50 Ky T O T A L STUDY SPECTRUM F - W - L O A D O R T E M P E R A T U R E 0 3 k I- J

0 1 5 10 15 20 25 30

MACH NUMBER

SECTION I1 - AERODYNAMIC DEPLOYABLE DECELERATORS - GER- 126 16

the drag forces increase and the deceleration rate becomes m o r e acute,

the possibility of aerodynamically heating the decelerator also inc reases .

The effect of this aerodynamic heating can be seen more readily by r e f e r -

ring to the thermal-performance pa ramete r s in Figure 2 . Since the major

emphasis in this study was on an altitude range f rom s e a level to about

200, 000 f t and a Mach range f r o m 1 .5 to 10, the parameters in Figure 2

cover only this range. In this f igure, lines of constant dynamic p res su re

and adiabatic wall temperature fo r turbulent flow a r e plotted a s a function

of altitude and Mach number. The lines form boundary condi-

tions for mater ia l strength requirements , while the lines of adiabatic wall

temperature foretel l approximate expectations of mater ia l temperature.

Thus, decelerators deployed in the Mach 1 to Mach 3 flight regime can

sustain a temperature r i s e of up to 7 0 0 F a s the deployment Mach number

approaches about 3 , while those deployed above Mach 3 can expect a t e m -

perature r i s e to above 7 0 0 F. Lowering the deployment altitude or i n -

creasing the dynamic p res su re decreases the t ime over which dece lera-

tion occurs , and thus hastens the temperature r i s e of the decelerator

mater ia l toward the appropriate adiabatic wal l- temperature line.

3. DESIGN CONCEPTS

To meet the requirements of space-age recovery, various deployable de-

celerator designs have been proposed, each of which suggests some po-

tential competitive advantage o r advantages. Various programs have

been conducted to advance the s tate of the a r t , and valuable data have

been obtained. Some applicable data, especially fo r configurations of a

basic geometr ical shape, have been obtained f r o m programs with nonre-

lated objectives.

By definition, deployable dece lera tors a r e devices that a r e packageable

and a r e capable of being extended o r inflated to an enlarged blunt shape.

F r o m this definition and based on the degree of completeness of the ex-

per imental investigations previously conducted, the main decelerator

140

120

100.

80

60

t W W LL LL 0 m 40. 0 z Q m 3 0 I t 20 W n 3

t t _I <

0

MACH NUMBER

I

0

- I I-

I

/- /

/ /I

/

I /

/ /

dH

I- /

/

/

-

1 2 3 4 5 6 7 8 9 to

SECTION I1 - AERODYNAMIC DEPLOYABLE DECELERATORS GER- 126 16

candidates a r e shown in F igu re 3 . For purposes of terminology, the types

of dece le ra to r configurations a r e fu r the r b roken down a s follows:

1. Two body (towed)

a . Nonporous

F o r c e d inflation

R a m - a i r inflation

b. Po rous

Designed f o r superson ic operation

Sub sonic modified

2. Single body (a t tached) - nonporous

a . Bas ic single shape

b, Composite shape

In the discuss ion that follows, the var ious configurati.on construction de -

t a i l s a r e p r e s e ~ t e d , The apparent per formance and design advantages of

each concept in t e r m s of why they a r e likely dece le ra to r candidates a r e

given.

a Of the ten concepts, p resen ted in F igu re 3 , the cone, sphe re , Ballute,

and f l a r e d s k i r t a r e a l l nonporous types that e i the r car, be at tached to o r

towed by a payload. These four concepts have ce r t a in des i rab le pe r fo rm-

ance cha rac t e r i s t i c s in common:

1. They a r e blunt-body, high drag -producing shapes .

2 . They can be inflated to a c lose , coupled position

behind the payload.

3, Since they a r e nor,porous, these dece l e r a to r s ac t

a s p r e s s u r e v e s s e l s and r ema in fa l r ly r igid when

inflated,

In the pas t the cone, sphe re , and f l a r e d s k i r t have been inflated with

compres sed a i r o r nitrogen. Ballutes have been inflated e i ther with

a TM, Goodyear Aerospace Corporat ion, Akron, Ohio,

SE

CT

ION

11 - AE

RO

DY

NA

MIC

DE

PL

OY

AB

LE

DE

CE

LE

RA

TO

RS

G

ER

- 12

6 16

Fig

ure

3 - De

ce

lera

tor C

on

figu

ratio

ns


compressed gas o r with r am-a i r . Note the r a m - a i r inlets on the Ballute

in Figure 3 .

The sphere and Ballute can be made f rom fabric gores s imi lar to those

on the parachute. These gores not only can be sewn together to fo rm the

decelerator shape but a lso can be cemented o r welded together, depend-

ing on the type of fabric required.

The above-mentioned concepts a r e coated with various e las tomers to ob-

tain gas-tight integrity. In addition, the coating protects the cloth and i s

l e s s susceptible to temperature, water , and abrasion. The remaining

concepts shown in Figure 3 a r e the porous -type decelerators; namely,

parachutes. In a l l cases , the canopy geometric openness - that i s , the

porosity - i s the pr ime factor for satisfactory performance ( a stable,

high drag -producing canopy).

The three ribbon parachutes a r e named for their shapes: standard flat ,

conical, and hemisflo. All th ree chutes a r e made f r o m fabric gores .

Each gore i s composed of a given amount of horizontal and vert ical r ib-

bons plus radial webs. As the name implies, a standard flat ribbon

- canopy i s made f r o m a number of tr iangular gores sewn together into

a c i rcu lar constructed shape and i s capable of lying "flats' on a work

table. The conical ribbon chute i s s imi lar to the standard flat with t r i -

angular gores , except that a few gores a r e excluded and thus a constructed

shape resul ts in a f rus t rum of the cone. The hemisflo type i s made f rom

"shaped" gores , and the resulting inflated shape i s a near hemisphere.

The advantage of the conical over the standard flat 1s that the same C ' s D

a r e attainable with l e s s canopy fabric , The advantage of the hemisflo

over the standard flat o r the conical i s that the portion of the canopy ahead

of the canopy equator ac ts a s an extended skir t . Based on test resul ts in

general, canopies with sk i r t s have l e s s coning instability. These para-

chutes were designed originally fo r subsonic operation and were limited

in performance when ca r r i ed to supersonic speeds.


a The f inal t h r ee parachutes , the Hyperflo, the Pa ra son i c , and the C

Supersonic Guide Sur face , a r e configurations designed for superson ic

operation. Al l of these types in e s sence have extended s k i r t s . These

s k i r t s a r e essen t ia l ly nonporous to a id the inflation retention capability.

The Hyperflo has a constructed f la t top called the canopy roof. This

roof can be made e i ther f r o m ribbons o r f r o m a m e s h o r net type cloth

s t ruc tu r e . With shaped go re s , the Pa ra son i c i s a n evolved canopy con-

f iguration that m o s t nea r ly m e e t s the membrane shape requ i rements of

an isotensoid design f r o m predic ted superson ic p r e s s u r e loadings. Coat-

ing of the canopy mesh- type crown provides for not only the p rope r

choked flow but a l so fo r t he rma l protection. The Supersonic Guide Su r -

face configuration i s shaped l ike a supersonic-subsonic di f fuser (flow

conver te r ) . In addition to this convergent, d ivergent shape canopy

(which has a l a rge vent i n the crown) , a s m a l l conical body i s suspended

ahead of the canopy l ip to induce the format ion of a n oblique shock.

Tables I through X s u m m a r i z e the known pert inent documented analyti-

ca l and exper imental investigations conducted on the candidate con-

f igurat ions . The information i s presented with the r epo r t ( o r t es t ) da tes

in chronologically descending o r d e r to indicate the evolution of 'the

var ious configurations and to suggest the p r e sen t s ta tus of each . The

tabulated h i s to r ica l information indicates the type of documented data

that i s available.

F igu re 4 depicts the miscel laneous configurations. These concepts a r e

labeled miscel laneous s ince l i t t le o r no exper imenta l p rog rams have

been conducted. While s o m e theore t ica l work has been done, the m a -

jor i ty of these concepts a r e a t be s t only ideas .

Concepts of i n t e r e s t a r e l i s t ed i n the following tab les :

-- a

Regis te red , U . S. Patent Office, Cook E lec t r i c Co. , Chicago, I l l inois.

b ~ ~ , Goodyear Aerospace Corporat ion, Akron, Ohio. C

Reg is te red , U. S, Pa ten t Office, Univers i ty of Minnesota, Minneapolis, Minn.

SECTION I1 - AERODYNAMIC DEPLOYABLE DECELERATORS GER-12616

TABLE I - R AND D - CONE DECELERATORS IN F R E E STREAM

I I cone conficuration I I I I

Report

SC-R-64-1311 (Ref 2 )

JPL-TR-32-677 11/64 (Ref 3)

NASA TN D- 2283 (Ref 4)

NASA TN 0-840 (Ref 5)

MSFC-MTP- AERO-61.38 (Ref

U of C: HE- 150-190 (Ref 7)

NAA/MD-59- 453 (Ref 8)

NASA TN D-176 (Ref 9)

Hoerner (Ref 10)

angle. 9,

Newtoman

5/64

6/61

5 61 6) 1961

1960

1959

1958

NACA TN 3788 (Ref 11)

Convair: ZA-7- 017 (Ref 12)

5 to 50 1 Sharp 1 Newtonian

1956

1955

6 tn 50 I Sharp 1 Newtonian

None

0 to 35 I Sharp / N m

lype of data obtained

Experimental Force and

1 to 6. 9

Static

None CA. CN. CM Static and dynamic

r o c N 1 iD 1 None

6.8

6.8

0.5 to 4 . 4

Pvrpoae and remarks

Obtain experimental results and compare with theory; determine effects of bluntness

Obtain experimental results and compare with theory; determine effects of bluntness

Obtain experimental reaults and compare with theory

Obtaln experimental results and compare wlth theory

Obtain experimental results and compare with theory

Determine experimental hypersonic force and stability data

Obtain experimental drag and pressure data

0 to 90 Sharp Newtonian None Cp CA, CN, CM None Presentation of theoretical ssro- dynamic data

All I Sharp 1 N o / 1 to 10 1 Cp 1 CD I None 1 Presentation of drag and prcs- sure data

None

None

None

CA. CW CM

CA. CN, CM

CA, CN. CM

Sharp

Sharp and blunt

Development of analytical tsch- niquea; presentation of the indicated data; and cornpariaon of theoretical methods

Static

Static

S t a t ~ c

CA. CN, CM

CD Development of theory and com- narison with e x ~ e r i m e n t a l resulta

Potential, Newtonian

Modified Newtonian

Static and dynamic

Static

J. Aeron. S c i , I I952 / I Sharp 1 S e n d - d 1 N o I None 11 None Vol 19 (Ref 13) theory (re-

vised) J. Math and 1 1952 Sharp I Second-0rd.1 1 None / Nono I None I None 1 Phys . , Vol30 (Ref 14) theory

Development of theory

1081 (Ref 15) Second-order None None None None theory

Lkvelopmant of theory

None

Subsonic, 1 to 4

3. Aeron. Sci., 1 1951 Vol 18 (Rsf 17)

CP

None

(Ref 20)

MIT TR-5 (Ref 18)

Rand T-8 (Ref 19)

Sharp

Sharp

Sharp

Sharp

1949

7/48

Corrected f l r s t order

Second-order theory

Stone's and second order

Stone's and f i ra t order

6.86 and 16

Nane

None

None

C~

C~

Nane

None

None 1 None Development of theory and com- pariaon of theoretical and experimental resulta

Development of theory and tabu- lation of reaults

Development of theory and tabu- lation of resulta (8 = 5 to 25 dsg)

Development of theory

None

None

None I S h a v 1 o d e 1 N o I None 11 None 1 None 1 Development of theory

(revisedl

None

None

None

MIT TR-3 (Ref 21)

MIT TR-I (Ref 22)

1947

1947

Sharp

Sharp

Stone's second order

Stone's second order

None

None

None

Prea- sure

None

None

None

None

Development of theory and tabu- lation of results (OS = 5 to 50 deg)

Development of theory and tabu- lation of results (I3 = 5 to 50 dag)

S E C T I O N I1 - AERODYNAMIC D E P L O Y A B L E D E C E L E R A T O R S G E R - 126 16

T A B L E I1 - R AND D - TOWE)-CONE D E C E L E R A T O R S

1 I T e s t M.ch

Reference

RTD-TDR-63-4023 (Ref 23)

RTD-TDR-63-4242 (Ref 24)

RTD-TDR-63-4242

RTD-TDR-63-4246 (Ref 25)

RTD-TDR-63-4226

Repor t d a t e

1/65

12/64

12/64


NASA T N D-994 12/61 (Ref 28)

4/63

NASA TN D-1789

ASD-TDR-62 -702 P a r t II (Ref 27)

12/62 0 . 8 ~ I Cone -cy l inder ,

f l a r e ( F . R . = 4. 34)

n u m b ~ r (wind-tu~nel)

da t i --

0 . 8 5 to . 2

Configuration

1 , 2

I 1 , 2

1 , 2

1 , 2

2 . 0 5

Cone-cylinder ( F . R . = 4 . 5 )

e\8 45

Hemisphere-cy l inder , f l a r e (F. R. = 1.06)

Ogive cy l inder ( F . R . = 4 . 5 )

Hemisphere-cy l inder , f l a r e ( F . R . = 1.06)

Ogive cy l inder ( F . R . = 4.5)

Cone-cylinder ( F . R . = 10.7)

0 .89 / Cone-cylinder, f l a r e (F. R. = 4.34)

x/d

2, 4 , 7.89

Visual coning observa t ion i

NASA T N D-994

Preceding page, blank

D/d

1 , 2

Forebody

Ogive cylinder ( F . R . = 4 . 5 )

30 / 2 t 0 6

(forebody with and without d e - c e l e r a t o r )

Type of da ta obtained

1.57, 2, 2 . 8 7

Same I

P r e s s u r e

None

( d e c e l e r a t o r and forebody)

F o r c e and m o m e n t

( d e c e l e r a t o r and forebody)

Stabil i ty

None

None

None

None

' None

None

None

None

None

None

T e s t purpose and r e m a r k s

Obtain exper imenta l aerodynamic da ta ; sol id st ing-mounted model used




Obtain exper imenta l aerodynamic da ta ; so l id st ing-mounted model used

Obtain e x p e r i m e n t a l aerodynamic d a t a for sol id cones on f lexible towlines; t h r e e of four cones had d i s k ex tens ions

Obtain exper imenta l aerodynamic da ta using a n inflatable f a b r i c A i r m a t cone on a f lexible towline

Obtain exper imenta l aerodynamic da ta using a st ing-mounted ( a t b a s e ) d e - c e l e r a t o r

Obtain e x p e r i m e n t a l aerodynamic da ta using a st ing-mounted ( a t b a s e ) d e - c e l e r a t o r

2; ( d e c e l e r a - 1 CD


Reference ~;EP: JPL-TR 34-160 (Ref 29) 6/61

Rand RM 2678 (Ref 30) 11/6

F1. Dyn. Drag - Hoerner 1958 (Ref 10)

J . Aeron. Sci . , Vol 24 (Ref 31)

J. Aeron. Sci. . Vol 20;

J . Aeron. Sci. , Vol 12 1945 (Ref 34)

1957

1953

J . Aeron. Sc i . , Vol 18 (Ref 33)

TABLE I11 - R AND D - SPHERE DECELERATORS IN F R E E STREAM

NavOrd Repor t 2352 (Ref 32)

1951

Sphere diam. (in. )

1/16 to 1/2

0. 09 to 1. 5

. . .

3/8

1. 14 X lo3

to 8 . 4 X 10 5

15 to 600

Type of data

Type of tes t

Wind tunnel

Experimental pa rame te r s

11 to 64. 7

1 to 10

2. 2 to 9. 7

Ball ist ic range

Wind tunnel

9/32,9/16,1-1/2

T e s t purpose and r emarks Mach no.

3 .8 to 4. 3

CD I Obtain drag in low-density supersonic flow

0. 002 to 4

. . .

. . .

0. 29 to 3. 96

Knudson no.

0. 25 to 0. 107

CD I Investigate Mach no. and Reynolds no. effects on drag

Reynolds no.

50 to 1000

5 3 X 10 to

2 X lo6

. . .

. . .

D

C~

D

. . . CD I Investigate Reynolds no. effects in a ve ry low density flow

Hotshot tunnel

Wind tunnel and ballistic

Ballistic range

(Data in a i r and helium) to obtain drag a t very high velocit ies in continuum and nea r - f r ee molecular flow

Presenta t ion of experimental data

Obtain supersonic and hypersonic d rag data

9. 3 X 1 o4 to 1. 3 X 10 6

Preceding page ,Hank

Ballist ic range C~ Investigate Mach no. effects on drag

SECTION I1 - AERODYNAMIC DEPLOYABLE DECELERATORS GER - 126 16

TABLE IV - R AND D - TOWED-SPHERE DECELERATORS

Reference

C o n i i e u r a t ~ a n

Repor t date

Tvve of data obtalned 1 Type of

t e s t

I T e s t purpose and r e m a r k s

Obtaln aerodynamic data , solid s t ing- mounted models (0 8- and 1. 6- in . d i a m ) used

2 4, 7 89 / 1, 2 I None 1 Ogive-cylinder 1 0. 85 t o 1 . 2 1 (F. R. = 4 . 5 )

(forebody with and without decel . )

T e s t Mach no. X/d

Wlnd tunnei

Wind tunnel

Wind tunnel

D/d Fence

(percent )

RTD-TDR-63- 4242 (Ref 24)

, . Forebody P r e s s u r e

Obtain aerodynamic data , so l id s t tng- mounted models (9116- and 1-1/8-in. d i a m ) used

2 t o 8

4 t o 8 Obtain aerodynamic data ; solid s t ing- mounted models (9116- and 1-1/8-in. d i a m ) used

F o r c e and moment

RTD-TDR-63- 4226 (Ref 25)

Stabtlitv

1. 2

1, 2

2 t o 8 Obtain aerodynamic data ; solid s t ing . mounted models (9/16- and 1-1/8- in .

c e l e r a t o r and d i a m ) used forebody) I 4 to 8 1 1. 2 I N m e 1 O i - y d 1 4. 35 I C

Wind tunnel Obtain aerodynamic d a t a , so l id s t ing- (F. R. = 4.5) PBS 'PQ ' d e 1 'D 1 1 1 mounted models (9/16- and 1-1/8-in.

c e l e r a t o r .and diarn) u s e d forebody', '

None

None

NASA T N D- 1789 (Ref 26)

Cone-cylinder (F. R. = 18.7)

H e m i s p h e r e - cyl inder , f l a r e ( F . R . = 1 . 0 6 )

Ogive-cylinder ( F . R. = 4.5)

None *

*

*

*

9"

None

0 . 8 5 t o 1 . 2 5

4 .35

Wind tunnel

Wind tunnel

Wind tunnel

Wind tunnel

Free flight

Wind tunnel

Obtain aerodynamic data ; so l id s p h e r e s on flexible towline (4-, 6-, and 8-in. d iam) used

Obtain aerodynamic data ; so l id s p h e r e s on flexible towline (4-, 6-, and 8-in. d i a m ) u s e d

Obtain aerodynamic d a t a , so l id s p h e r e s on flexible towline (4-. 6-, and 8-in. d iam) used

Obtain aerodynamic data ; inflatable f a b - r i c s p h e r e on flexible towline (8-in. d i a m ) u s e d

CD None

NASA T N D- 1789

NASA TN D- 1789

(forebody with and without decel . )

None

Cone-cylinder, f l a r e ( F . R. = 4 . 3 4 )

E g g e r s body with f laps

None

None

None

CD

6. 25

3 . 9

None

None

Cone-cylinder ( P . R . z 10.7)

Spiked cone- cylinder

None Obtain d a t a and investigate f r e e flight capabi l i t ies ; 9-it-diam p r e s s u r i z e d fabr ic models used

NASA TN D- 9 19 and ASD- TR-60-182 (Ref 36 and 37)

None, unsym- m e t r i c a l capsu le , a t tached spike

Obtain aerodynamic data ; a11 8-in.- d i a m models , s o m e inflatable, s o m e fabr ic-covered solid models u s e d

S y m m e t r i c a l and unsym- m e t r i c a l capsu le , sphere . d isk

S y m m e t r i c a l and unaym- m e t r i c a l capsu le , s p h e r e , d isk

S y m m e t r i c a l capsule ( s t r u t - mounted)

I Wind tunnel I !

I

' 1

,

None i

O b t a ~ n aerodynamic d a t a , a l l 8 - ~ n . - d i a m r n o d e l ~ , s o m e ~ n f l a t a b l e , s o m e fabr lc-covered solid models used

I

CD

C~

C~

*Visual Coning Observation /4- f l

Preceding page blank

None

C

* Wind tunnel Obtain aerodynamic data ; 26. 1-in. f a b r i c s p h e r e ( p r e s s u r i z e d ) ; f i r s t supersonic-deployment d e m o n s t r a - tion

SECTION I1 - AERODYNAMIC DEPLOYABLE DECELERATORS GER- 12616

Reference

AEDC-TR-65-218 (Ref 38)

Unpublished data (Ref 39)

Unpublished (Ref 41)

Unpubl~shed da ta (Ref 42)

GER-11665 S/3 (Ref 43)

GER-1 I665 S/2 (Ref 44)

GEil-11665 S/1 (Ref 45)

Unpublished data (Ref 47)

AEDC-TDR-64-65 (Ref 48)

GER-11538 (Ref 49)

AEDC-TDR-63-119 (Ref 50)

ASD-TDR-62-70?,, P a r t I1 (Ref 27)

ASD-TDR-62-702, P a r t 11

ASD-TDR-62-70?., P a r t I1

ASD-TDR-62-702, P a r t IT

- -

Report date

- -

T e s t date

Tes t configuration

Forebody I Decelerator

TABLE V - R AND D - FREE-STREAM

Blunted oglve ( F . R . = 2.391, strut-mounted

Unsymmetrical forebody

AND TOWED-BALLUTE DECELERATORS

Cone-cylinder, flare-cylinder ( F . R . = 7.8)

Small rigid model ( ~ s o t e n s o ~ d ) aft- sting mounted

R a m - a ~ r - l n f i a t e d coated nylon model soten en so id)

Nylon r a m - a i r cone-balloon

Cone-cylinder, Ram-al r Namex f la re-cyl inder model (isotensoldl ( F . R . = 5.82)

U n s y m m e t r ~ c a l Nylon r a m - a i r s led

Cone-cylrnder. Nomex r a m - a i r f la re-cyl inder model (isotensoidl ( F . R . = 61

Cone-cylinder. Nylon ram-ai r f la re-cyl inder model (isotensoidl ( F . R . = 6)

Cone-cylinder, Nylon r a m - a i r flare-cylinder model (isotensoid) ( F . R . = 6)

Tow-atrut used Nylon r a m - a i r (no forebody) model (ieotensoid)

Cone-cylinder, flare-cyltnder ( F . R . = 5.82)

Cone-cylinder, flare-cylinder ( F . R . = 7.81, and connecting snaft

Not towed ( n o forebody)

Biconic ( F . R . = 51

Nylon ram-ai r model (isotensoidl

Small rigid >sotensoid model; aft-sting mounted

Rigid ieotenoid model; aft-sting mounted

Nylon r a m - a l r i s o t e n s o ~ d model

Cone-cylinder Nylon r a m - a i r ( F . R . = 10.71 1 cone-balloon Cone-cylinder ( F . R . = 10.7)

Hemisphere- cylinder, boattail

Hemisphere- cy l inder , boattall

Dacron ram-ai r isotensold model

Metal cloth, flexible, r a m - air isotensoid model

Rigid isotensoid rnadel

Apex

75 7 in.

80 I 7 ' 5 i n '

Fence (percent )

10

10

6.30

0

LO

0

10

10

10

10

10

10

10

6 .3

3.9

0

0

Type of data obtalned

Force

forebody wake

Mach no.

: . 9 8 1 0 3 . 9 8

2 . 6 . 3 . 0

4 to 6

3

1 .36 (de- ~ 1 0 ~ )

2 .4 to 3. 15 (deploy M E 3.25)

1 . 0 te 1 .88 fdepluy M = 2. 17)

Obtain towed drag data and v isuz l stabili ty for relatively la rge rnadel

T e s t condt t~ons

q (ps i )

158

120

144 to 245

120

2380

50 to 208

32.5 to 240

cD * Wind tunnel Obtam aerodynamic drag a n d visual

None 1 CD I * ( T r a c k Obtain high-q d r a g and stabili ty data I

l t 2 (deploy M = 2.5)

1.92

2 .53 . 2.79, and 3

1 .5 to 6

1 to 2.5

4 to 5.5

X/d D/d

2 , 3 1 .06 1 . 3 , 1 .8

6 1 .23

9 3 . 5

10 .2 3.4

7 . 2 3

7 3 . 4

7 3 . 4

None

3 6 1 4 4

121

.. . .

1 . ,

,

CD

Internal

Internal

None 7 3 . 4

. . .

3.07 1 .7

6 to 3. 75 12

. .

8 . 0 2 .0

Obtain towed free-flight t e s t per - formance charac ter i s t ics and aerodynamic data

None

None

None

Internal

None

None

CP

t

C and P~

internal

None

t

4

*

t

None

C~

=D

Wind tunnel Obtain towed d r a g data up to Mach 5. 5 and v isua l stabili ty

Wind tunnel

None

CD

Wind hlnnel Initial feasibili ty tea ts to demonst ra te 1 r a m - a i r inflation ( f ree of "buzzing") of textile inflatable models and obtain

stabili ty in wake of unsymmetr ica l forebody

Obtain high Mach no. towed drag data and visual stabili ty

*

*

J Itowed d r a g data and visual atabili ty

None

None

Wind tunnel

Wind tunnel

Wind tunnel Obtain towed-model tempera ture and p r e s s u r e data

Demonst ra te Ballute deployment and obtain drag and a t a b i l ~ t y data

Obtain towed drag and atabili ty data

Wind tunnel

Wind tunnel

Wind hlnnel

Obtain d r a g and preaaure da ta over a wide -L- range

Obtain f r e s - s t r e a m drag data

Mach LO per formance tes t s ( s a m e as above) of coated metal-cloth models

21-13 3 2 J - 4 Precedjng page blank *

ASD-TDR-62-702 ( P a r t I), ASD-TR- 60-182 (Ref 27. 36)

1 Visual coning observation. .. <:,?V

9/62. 11/61


P r e s s u r i z e d fabr ic spher ica l models

. . . 9 f t 3 .9 1.4 to 2 . 1 . . . 8 I2 None CD * F r e e flight Demonstrate feasibili ty and obtain

data during flight of nonporous inflatable model

/ SECTION 11 - AERODYNAMIC DEPLOYABLE DECELERATORS GER- 12616


Yheory Expe r imen ta l

Mach No. Re fe rence

WADC-TR-59-324, P a r t I1 (Ref 52)

OML Repor t 6 R 2 P (Ref 53)

( F . R . = 1 .6 and

6/65 1 to 2 .896

I Cp

I cA. cN. cM I Static

Date

Type o f da ta obtained

0 , 10, 20, 3 0

12/60

6/55 I 45-degcone -cy l inde r 1 .3 , 1.8 , 2.5 I None I None I None Static ( cy l inde r : 1, 3 , 5 ( l ineabized theory)

P r e s s u r e

45-deg cone-cyl inder ( F . R . = 2 .21 and 5 . 21)

Hemisphe re - cyl inder

30, 50, 70

6 , 14, 22


F l a r e configuration F o r c e and

momen t €Is (deg)

Modif e d Newtonian i I J

Stabil i ty Forebody . --

6 None C A P CN, CM Static


TABLE VII - R AND D - HEMISFLO, CONICAL, AND STANDARD F L A T RIBBON PARACHUTES

Report Reference

110 (Ref 40)

AEDC-TDR- I 6/64 64-120

AEDC-TDR- 64-120 (Ref 55)

6/64

FDL-TDR-64- 66 (Ref 65)

AEDC-TDR- 63-263

5/64


1/64

AEDC-TN-59- 9/59 107 (Ref 61) I


NASA TN D- 752 (Ref 59)

NASATMX- 448 (Ref 60)

12/62

5/61

11/60

Cone -cylinder (F. R. = 6. 16)

Test date



Test configuration

Forebodv I Decelerator

Cone- cylinder flare-cylinder (F. R. = 5.82)

Cone-cylinder flare-cylinder (F.R. = 5.82)

Unsymmetrical tes t sled

Geometric porosity (percent)

Cone -cylinder f lare-ci l inder (F. R. = 7.8)

Cone-cylinder flare-cylinder (F.R. = 7 . 8 )

Biconic (F . R. = 5) Mercury capsule


B-58 unsymmetr ical capsule

I Reefed hemisflo, 13 and 21. 3 in.

I Conical, 10-ft

Hemisflo, 4.2-. 5.54-, 6.77-ft

Do Hemisflo, 19. 3 - in. Do

I Conical, 1-ft D

Standard flat, 9.6 in.

Conical, 6 f t ; standard flat, 6 f t

Equiflo, 1 -ft Do

14 (13 in. ), 17 to 9 (21.3 in .)

14. 3

Not r e - corded

Reefed to 'x' percer: of Do

. . .

None

None

20

2 0

None

20.7, 23.4

2 0

None

None

None

None

Free flight Free-flight demonstration and f ree - . 18 to 2.15 None I CDo 1 ,* 1 1 (deploy M = flight results 2.4)

Mach no.

1 .5 to 3

Wind tunnel Demonstrate supersonic feasibility 1 . 8 l o l . O 1 None 1 CDo 1 * I 1 of reefed chutes

Type of test

Wind tunnel

1 . 2 9 t o 1 . 4 6 I None I cDo I 4 Track Obtain transonic, high-q perform- (deployment) ance data

Test purpose and remarks

Demonstrate supersonic feasibility of reefed chutes

Type of data obtained

Free-flight demonstration and f r e e - flight results

Demonstrate supersonic feasibility of reefed chutes

2 to 3.39 (deploy M = 3.44)

1 .8 to 3 .0

Wind tunnel Demonstrate supersonic feasibility 1 . 4 8 l o 2 . 9 8 Nine I C 4 1 * / 1 of reefed chutes

1.48 to 2.98 I I CDo I * I Wind tunnel Demonstrate supersonic feasibility of reefed chutes

Stability

*

Pressure

None

None

None

Force and moment

C =o

0 . 8 t o l . 6 I None 1 CDo I x< I Wind tunnel B-58 escape-capsule stabilization I tes t

C Do

C Do

* ~ i s u a f coning and inflation observation.

Obtain supersonic-performance data

Mercury program: f i rs t -s tage drogue feasibility

To obtain flight-test data

1.48 to 2.98

1. 82 to 2 .5

1 to 1 .5

Preceding page Mank

*

*

F r e e flight

Wind tunnel

None

None

None

C Do

C Do

C Do

xc

4

*

Wind tunnel

Wind tunnel

Free-flight drop

--

SECTION I1 - AERODYNAMIC DEPLOYABLE DECELERATORS GER- 126 1 6

TABLE IX - R AND D - TENSION-SHELL

Tension she l l s , P = 15. 4 to 47 deg (Wsemiapex angle), Ref 65

T e s t purpose and r e m a r k s T e s t date

25-deg (0) towed tension shel l behind X-15 a i r c ra f t , Ref 67

Flexible tens ion she l l (a luminum t o r u s and f a b r i c ca t ena ry cu r t a in nose s e c - t ion) , Ref 27

3/65

Repor t date

Newtonian tension shel l , Ref 66

None 1 4 .65 None

Newtonian

Newtonian

None I 1. 82. I None

Configuration

None

Coning and f a b r i c f lu t ter

3, 7

None

W i n d tunnel

Wind tunnel

Unpublished d a t a ( N A S A / L ~ ~ ~ ~ ~ Uni tary W. T. )

Theory

Local p r e s s u r e

C P

ASD-TDR-62-702 ( P t . 11)

Type of t e s t

Obtain pe r fo rmance c h a r a c t e r i s t i c s behind unsymmet r i ca l forebody

Refe rence T e s t

m a c h n o .

CD

CD

Evaluate potential h igh-drag low-weight c h a r a c - t e r i s t i c s and qualitatively a s c e r t a i n s tabi l i ty

Type of da t a oltained

None

None

Stabili ty P r e s s u r e

Wind tunnel

None

F o r c e ald momeol '

AIAA pape r , p r e - sented 7/26-29/65

NASA TN D-2675

Study pe r fo rmed to a s c e r t a i n aerodynamic c h a r a c t e r i s t i c s and s t r u c t u r a l efficiency

Theoret ica l s tudy to evaluate h igh-drag low- weight cha rac te r i s t i c s

Reference

ASD-TR-61-348 AEDC-TN-61-4 (Ref 68 and 69)

Same

Ao:ro R e s e a r c h Repor t s ARC- R - 177 and ARC- R-176 (Ref 70 and 71)

AFOSR- 104 (Ref 72)

Date

1 /62

(Also Phase I Report , 1/61)

2/65

3/6 1

Configuration

0. M.* M a r k 111-A (launch position) d rag b rake

0, 10, 20, and+40 deg ( r i b angle) I. S. M a r k I -B d rag b rake

10 deg 0. M. M a r k 111-A d r a g b r a k e

F. sf M a r k I (fully opened) d r a g b rake

Rotor net

Flexibrake, i nve r t ed d r a g cone, d r a g ring, paraf lap , p a r a s k i r t

' 0 . M. - Orbi ta l model

t I. S. - Ins t rumented sa te l l i te (model)

*F. S. - FUII sca l e


TABLE X - MISCELLANEOUS CONFIGURATIONS

Theory

Newtonian

Newtonian

Newtonian

Newtonian

. . .

. . .

T v ~ e of da ta obtained

T e s t m a c h no.

2, 4, 6. I Cp I CA. CN. Sta t ic and Wind 8 1 dynamic 1 tunnel

Subsonic to 6. 0

T e s t purpose and r e m a r k s

, .

Obtain pe r fo rmance da ta of o rb i t a l mode l s a t va r ious angles of a t tack and var ious environmental conditions

P

A s above with I. S. models

Type of t e s t P r e s s u r e

AS above with o rb i t a l mode l s

As above with F. S. models

Analytical s tudies - no t e s t s

CA;CN, CM

Feas ib i l i t y s tudies - no tests

F o r c e and moment

31-fi


Stabili ty

S t a t i c a n d dynamic

Wind tunnel


P A R A F L A P

F L E X I B R A K E

R O T A T I N G N E T

I N V E R T E D D R A G C O N E

I N F L A T A B L E

DRAG R ING

I N F L A T A B L E

P A R A S K I R T

Figure 4 - Miscellaneous Dece le ra tor Concepts


SECTION XI - AERODYNAMIC DEPLOYABLE DECELERATORS GER- 126 16

1 . Blunted and shape f r e e - s t r e a m cone configuration, Table I

2. Towed- cone configurations, Table I1

3 . F r e e - s t r e a m sphe re configurations, Table III

4. Towed- sphe re configurations, Table XV

5. F r e e - s t r e a m and towed Ballute configurations, Table V

6 . F l a r ed - s k i r t configuration, Table VI

7 . Hemisflo- type ribbon parachute configurations, Table VII

8 . Conical r ibbon parachute configurations, Table VII

9. Standard f la t ribbon parachute configurations, Table VII

1 0 . Hyperflo parachute configurations, Table VIII

11. Pa ra son i c parachute configurations, Table VIII

12. Supersonic Guide-Surface parachute configurations, Table

VIII

13. F r e e - s t r e a m tension she l l ( tension shape) configurations,

Table IX

14. Towed tension she l l ( tension shape) configuration, Table 1X

15. Miscellaneous configurations, Table X

4 . AERODYNAMICS

a . Gene ra l - A review of the h i s to r ica l data obtained on the type of investigations coz-

ducted r evea l s , a s a n in i t ia l p rob lem a r e a , the gene ra l l a ck of data con-

cerning blunt-body superson ic ae rodynamic per formance . Prev ious ef-

f o r t s to ob ta inper formance data of s lender bodies emphas i zeda reduction

of d r a g f o r superson ic lifting-flight application. There fore , the bas ic R and D philosophyfor dece l e r a to r s was to r e v e r s e the p rocedure completely

SECTION I1 - AERODYNAMIC DEPLOYABLE DECELERATORS G E R - 126 16

and conduct inves t iga t ions on blunt bod ies , us ing methods to i n c r e a s e the

d rag .

R e s e a r c h and development p r o g r a m s in the p a s t have r e l i e d upon one of

two methods to effect r e c o v e r y and to obtain da ta in the development of

s u p e r s o n i c h igh-drag dev ices .

One method was the "evolut ion approach , I ' i n which exist ing subsonic p a r a -

chute des igns w e r e modified slightly, mode l s w e r e built ( r ig id and f l ex -

ib le ) , and t e s t s above Mach 1 w e r e m a d e in s m a l l i n c r e a s i n g velocity s t e p s .

Based on the r e s u l t s of t h e s e t e s t s , addit ional des ign modificat ions w e r e

m a d e , mode l s w e r e built and t e s t e d a t s l ightly h igher Mach n u m b e r s , and

the cycle was repeated . A signif icant advantage of th is method i s that a

cons ide rab le backlog of knowledge i s used to enhance the chance of s u c -

c e s s . P a s t exper ience ind ica tes that this technique h a s beenapp l i ed with

l imi ted s u c c e s s . Unfortunately, s ince b a s i c p r o b l e m a r e a s a r e not a lways

defined comple te ly , the solut ions that a r e obtained m a y be unique to a

p a r t i c u l a r opera t iona l s i tua t ion . Hence a "f ix" i s m a d e , but the g e n e r a l

p rob lems often r e m a i n unsolved.

The second method ini t ial ly i n c o r p o r a t e s p e r f o r m a n c e c h a r a c t e r i s t i c s of

bas ic blunt-body g e o m e t r i c s h a p e s in the development of superson ic d e -

c e l e r a t o r s , S m a l l r igid mode l s ( so l id o r r ig id ized by in te rna l p r e s s u r i -

za t ion) a r e built and t e s t ed without c o n c e r n , in i t ia l ly , f o r the m e t h o d of

cons t ruc t ion . Once sa t i s fac to ry p e r f o r m a n c e c h a r a c t e r i s t i c s have been

obtained, subsequent de ta i led work i s w a r r a n t e d to obtain an eff icient light

weight deployable s y s t e m . In addit ion, d e s i r a b l e c h a r a c t e r i s t i c s of a

wide r va r i e ty of b a s i c shapes can be incorpora ted into a des ign.

The r e s u l t s of the two a p p r o a c h e s show the second to be m o r e eff icient .

This i s because , when b a s i c a e r o d y n a m i c p e r f o r m a n c e p r o b l e m s a r e

so lved, subsequent s u c c e s s f u l , l a r g e - s c a l e s t r u c t u r e and des ign inves -

t igat ions a r e m o r e read i ly a t ta inable s ince they c l e a r l y a r e dependent

on a n a c c u r a t e definition of the a e r o d y n a m i c p e r f o r m a n c e . I t ems - b

through - d , below, p r e s e n t the a e r o d y n a m i c p e r f o r m a n c e da ta , i n t e r p r e t e d

in t e r m s of the knowledge tha t has been gained, the p r o b l e m s tha t have

been solved, and the p r o b l e m s tha t r e m a i n t o be solved. - 3 5-


b. Steady-State D r a ~ of Towed Porous Decelerators -

The drag of a towed decelerator depends on the type of flow environment

that surrounds it. Since the decelerator i s being towed, i t must operate

in the wake of the towing forebody. In addition, the drag-producing ca-

pabilities a r e dependent on i t s own size and shape. Because of these facts ,

dimensionless "towed- condition" pa ramete r s x/d and ~ / d were established

to aid in evaluating comparative decelerator tes t data. x/d (the number of

payload calipers aft) descr ibes the decelerator -trailing distance (longi-

tudinal position in the wake) ; ~ / d (the rat io of decelerator -to-payload size)

indicates the t ransverse wake s ize, which - in turn - influences the flow

around a given s ize and shaped decelerator .

F igure 5 indicates the Mach-number l imits and the s izes and types of para-

chutes that have been flight tested. In addition, the t rack- tes t Mach num-

b e r l imits a r e shown. Results of hemisflo and Hyperflo t rack and wind-

tunnel tes t s a r e presented to show the l imited amount of data for cor re la -

tion between ground and flight t e s t s of the same configurations. Of all the

chute t e s t s , one available data point was found showing wind-tunnel drag

resu l t s at Mach 2. 5 for a 4. 12;ft Do hemisflo parachute, compared with

flight-test resu l t s fo r the same parachute. Significant aspects of the F ig -

u r e 5 plots a r e the CD dispersion between configurations and the apparent

inconsistency in drag t rends. Physical interpretation of these resu l t s can-

not be substantiated completely f rom this limited data. However, the ef -

fe cts of performance due to configuration and tes t - condition difference can

be explained a s follows.

It i s generally recognized that performance of parachutes operating in the

subsonic speed regime i s influenced by the degree of canopy porosity. Rib-

bon parachutes with a known amount of geometr ic porosity have been used

successfully for a wide variety of subsonic applications and at high sub-

sonic and transonic speeds. These parachutes have performed effectively

up to a f r ee - s t r eam Mach number of nearly 2 ; this i s because the local

flow behind the normal detached-canopy bow shock i s s t i l l subsonic, and

at about Mach 2 portions of the flow in the canopy do become supersonic.

R E F T Y P E SYM- MACH NO. TEST BO L PARACHUTE CONFIGURATION x/ d D/ d (DEPLOY)

54 1 R IBBON ROOF H Y P E R F L O , 3 .69-FT D 8.45 5.00 3.22 0 5 4 1 R I B B O N ROOF H Y P E R F L O , 3.69-FT Do 8.45 5.00 3.98

54 1 A 4.12-FT D HEMISFLO 1 2.00 4.70 3.39

5 4 1 a 4.12-FT D H E M l s F L o 12.00 4.70 2.40 0

. . . . . . . . . 56 2 0 6.77-FT D HEMISFLO

. . . . . . . . . 56 2 e l 6 .77-FT D HEMISFLO 0

. . . . . . . . . 56 2 0 5.54-FT D HEMISFLO

. . . . . . . . . 56 2 a 6.06-FT D R I B B O N H Y P E R F L o 0

. . . . . . . . . 56 2 D 3.69-FT D R IBBON H Y P E R F L O 0

. . . 59 3 6 0.80-FT D STANDARD F L A T 4.30 1.29 0

. . . 58 3 0 1.00-FT D C O N I C A L R I B B O N 8 .92 3.22 0

. . . 55 3 I7 ~ . I Z - F T D HEMISFLO 8.00 2.81 0

T Y P E TEST:

1 - F R E E F L I G H T

2 - TRACK

MACH NUMBER

SECTION LT - AERODYNAMIC DEPLOYABLE DECELERATORS GER- 126 16 ----

During the review of the smal l - s cale parachute wind-tunnel tes t s , the

higher-porosity parachutes tes ted between Mach 1 and 2 had both good

coning stability and good inflation stability, while low-porosity parachutes

gene rally had good inflation stability but poor coning stability . As soon a s the local flow into the canopy becomes supersonic, the influ-

ence of the amount of geometric porosity (and other fac tors ) on the pe r -

formance i s amplified, since a sys tem of unsteady shock waves resu l t s

when little o r no mass a i r fiow i s allowed through the canopy. Under this

condition of very low porosity, good inflation and high drag might be ob-

tained, except that the canopy experiences adverse coning oscillation since

the low -porosity canopies have basically unstable static -moment de r iva-

t ives, This coning i s considered adverse, because the cyclic breathing

that i s al.ready present due to the cyclic "source" (high-pressure outer-

wake a i r ) and "sink" (low-pres s u r e inner -wake a i r ) phenomenon i s a m -

plified by spillage of the canopy captured a i r .

On the other hand, canopies with higher values of geometric porosity (be - tween 20 and 30 percent) have improved stability character is t ics but lower

drag-producing character is t ics . In this situation a system of more stable

shock waves exists. It is fur ther noted, however, that this lower r e s t r i c -

tion of m a s s flow will resul t eventually in the bow shock being attached to

the canopy lip with increasing Mach number operation and subsequently

being swallowed in the canopy. This shock attachment and swallowing

causes the inflated canopy to assume a shape resembling that of a reefed

parachute. The drag charac ter i s t ics a r e then reduced substantially.

Hence, there i s a basic mismatch of a number of aerodynamic parame-

t e r s .

In the apeciftc parachute performance tes t s documented in Figure 5, some

of the above general performance tendencies did occur. It i s important to

note, however, f r o m the tabular model description and tes t condition datcl

accompanying the plotted performance data that a straightforward c:valua . tion of the meaning of the steady-state drag variat ior~ cannot o r should not

SECTION I1 - AERODYNAMIC DEPLOYABLE DECELERATORS G E R - 12616

be made . This i s because (1 ) the different s i z e parachutes w e r e towed

a t different locations in the payload wake and (2) the s t r u c t u r a l in tegr i ty

of the model , performing for var ious lengths of t ime p r i o r to obtaining

measu red data , was uncer ta in .

The parachutes (hemisf lo and Hyperflo) had extended sk i r t s coned l e s s

than the s tandard flat and conical chutes ; s ince the i r geomet r ic

porosi t ies w e r e l e s s than those of the s tandard flat and conical ribbon

parachutes , the i r drag-producing cha rac t e r i s t i c s w e r e higher and r e -

mained higher a t higher Mach number s .

F igures 6 and 7 p r e sen t superson ic wind-tunnel data , the t e s t condi-

tions of which a r e p resen ted in Table XI, fo r the l a r g e r parachutes

(2. 72 to 5. 5 ft in d i ame te r , Do) when the amount of canopy choking was

known and recorded . The configurations tes ted (specifically designed

fo r supersonic velocity) w e r e the Pa ra son i c and theHyperflo-type cano-

pies . Table XI p r e sen t s the t e s t conditions and the type parachute for

each data point shown in F igu re s 6 and 7 .

F igure 6 shows the model choking ra t io v e r s u s the Mach number a t :::

which the model was tes ted; the theoret ical i sentropic (A/A ) a r e a ra t io

for increas ing superson ic Mach numbers i s super imposed . F igu re 7

p resen ts the superson ic d r a g coefficient v e r s u s A. /A (canopy inlet 1 e

a r e a over canopy exit a r e a ) of the models tes ted. The re was a n apparent

t rend that the CD1s (coefficients of d r ag ) w e r e l a r g e r values when the

A was g r e a t e r than the isentropic A/AU; when the A . / A ~ was l e s s 1 e :* 1

than A/A , the CD1s w e r e s m a l l e r values - that i s , the parachute did

not take a full-inflated design shape. F igu re 6 shows that, to m e e t the

requ i rement that a parachute have choking g r e a t e r than i t s i sen t rop ic

a r e a ra t io , the design of a given parachute fo r operation a t higher Mach

numbers would r equ i r e a dec rea sed porosity. At Mach 5,

SECTION I1 - AERODYNAMIC DEPLOY ABLE DECELERATORS GER- 126 16

F i g u r e 7 - C vs Area Ratio f o r L a r g e S u p e r s o n i c Parachutes D

0.30

0 20

0 10

P

0 O 0

0 04

Ai/Ae

K E Y : SEE T A B L E X I FOR NUMERICAL D A T A POINT DESCRIPT ION

-

E X P E R I M E N T A L

I PARASONIC (Ai/Ae > A / A * )

5

12

H Y P E R F L O (A. /A > A / A * ) 1 e

I

n

MESH

! I I 1 I ,PARASONIC iAi/Ae < A / A * ~

I/ I I

( A ~ / A , < A / A * ) I I

11

4 5

-

2

6 7

D I \ / . / 3 ,

1 I

4"

o v n

2 3

SECTION I1 - AERODY1\3AMIC DEPLOYABLE DECELERATORS GER- 126 1t

TABLE XI - FIGURES 6 AND 7 DATA POINT TEST CONDITIONS

Data Reference point number q

1 0 55 12 1

2 0 55 119

3 0 55 12 0

4 A 62 119

4 ' A 62 120

4 " n 62 120

5 a 62 120

6 55 12,O

7 0 73 119

8 tl 62 12 0

9 0 55 12 1

l o a 55 12 1

1 1 b 62 12 0

1 1 ' b 62 120

l2 6 73 12 0

model x/d 1 li0/d 1 IyPe

9.75 1 2.72 1 Parasonic

9 .75 1 2 .72 1 Parasonic

9.75 1 2 .72 1 Parasonic

5. 80 2. 0 4 Parasonic

8. 5 1 2.72 Hype rf lo

8.51 1 2 .72 1 Parasonic

9 .75 2 .72 Parasonic

7. 16 2. 72 Parasonic

8. 5 1 2. 72 Hype rf lo

9.75 2 .72 Parasonic

9 .75 1 2 .72 1 Parasonic

8.51 I 3 * 7 0 I Parasonic

-1-

Exploratory mesh roof models.

fo r example, the canopy porosity would approach a solid canopy, which

would probably develop stability problems when ca r r i ed to a low Mach

number.

F igure 8 presents C versus Mach nulnber resul ts for both smal l - and D C

la rge-sca le Hyperflo parachute wind-tunnel model tes t s . The plots a r e

presented mainly to show the available documented data; a straightfor -

ward analysis of the meaning of the drag variation with Mach number

cannot be made since design and performance pa ramete r s - such as the

type of model (line length, canopy porosity), the type of model setup

SE

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11 - AE

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- 126 16

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(towline length, use of a swivel), and the actual tes t conditions (dynamic

p res su re , Reynolds number) vary widely. F r o m a review of the data,

the following might be postulated:

1. High CD1s f r o m Mach 1. 5 to 2. 0 occur because the

local flow i s subsonic.

2 . Peaks in the CD curves at Mach 3.6 to 4 . 4 occur

because the dynamic p res su res a r e minimum and

hence the stiffness of the sma l l models aids in

keeping them in their fully inflated shapes.

However, to attribute the higher drag values to mater ia l stiffness only i s

probably not completely valid, since a low q (dynamic p res su re ) a t a given

Mach number resul ts in a lower Reynolds number. A change in Reynolds

number reflects a change in forebody wake and hence a change in the p e r -

formance of the parachute. In addition, mater ia l fatigue causes deterio-

ration in performance with t ime in the wind tunnel, and wind-tunnel tes ts

a t various temperatures affect performance. Not only does the Reynolds

number change, but the mater ia l becomes stiffer; this added stiffness in-

fluences i ts inflated shape and hence i t s performance. Figure 9 gives the

average drag resul ts at various towline lengths during Mach 2 to Mach 2 , 6

wind-tunnel tes t s of a 4-ft diameter Supersonic Guide-Surfacc parachute.

The plots a lso show the variation in drag readings, which is believed to

be due to canopy breathing. Variation i s reduced with increased x/d.

Figure 10 shows the C,, of the guide-surface parachute at three Mach

numbers fo r a towline length that had the least amount of C D variation.

This variation varies between *7 to k16. 5 percent of average value.

Not enough documented data on supersonic tes t s of solid extended sk i r t -

type parachutes a r e available to make a data-correlation evaluation be-

tween wind tunnel tes t s and flight tes t s , since two of the three configura-

tions have not been flight-tested. The only available supersonic flight - tes t

data (above Mach 2 ) were for the "ribbon-roof l1 Hyperflo parachute; un-

fortunately, this parachute did not per form in a s imi lar manner in a wind


1.1

1 .o

0.9

0.8

T MACH 2.0 0.7

0.6

0.5 ti 0

0.4 8 10 12 14 16 18 2 0 X / ( i

1 . 1

1 .o

0.9

0.8

AT MACH 2.2 0.7

0.6 0 0 0 0.5

8 10 12 14 16 18 20 /

0.9

0.8

0.7

0.6 TMACH 2.6

0.5 0 0 0 0.4

8 10 12 14 16 18 2 0 x/d

F igu re 9 - Guide-Surface Parachute C,, vs x/d C


F i g u r e 10 - Guide-Surface P a r a c h u t e C vs Mach Number a t One D

C Towed Condition (with Min imum C Var ia t ion )

D

0.9

0.8

A V E R A G E C

0 .7

\ MIN - ~ B C V A R I A T I O N

0 . 6 .

0 n ' 0.5

2 .O 2.2 2.4 2.6 2.8

MACH NUMBER

D

\

TOWLINE x / d = 15.5

SOURCE-REF 55 1

SECTION I1 - AERO.DYNAMIC DEPLOYABLE DECELERATORS GER-12616

tunnel, a s evidenced by extremely heavy canopy breathing and the resu l t -

ing very low drag coefficients in a l l t e s t s . The "mesh-roof" Hyperflo

wind-tunnel t e s t s w e r e m o r e successful than those of the ribbon-roof

parachute; however, because of s t ruc tu ra l fa i lu res of the m e s h roof dur - ing flight t e s t s , no significant f l ight-test data were available for data

correla t ion. Therefore , the lack of parachute fl ight-test data m u s t be

considered a major void.

Based on available data with respec t to porosity conditions (A./A ) , no I e

one parachute apparently can be designed to operate successfully over a

wide range of supersonic Mach numbers . In addition the amount of

breathing that can be tolerated for successful operation r ema ins a void.

c . Steady-State Drag of Towed Nonporous Dece le ra tors -

Ballute decelerator representat ive supersonic drag data a r e presented in

F igu re 11. The data a r e for the l a rges t dece le ra tors tes ted. P a r t of

the data shows the var ia t ion in drag obtained while decelerating during a

flight tes t . Another pa r t shows the drag obtained at the highest Mach

number during deceleration in a t r ack tes t . The remaining data show

the drag obtained in wind-tunnel t e s t s during a number of constant Mach-

number runs . In summary , the meaning of these data i s a s follows:

1 . A drag coefficient above 1 can be obtained between

Mach 1 and Mach 2 .

2 . At a given se t of design conditions, a conventional

10 percent fence model can obtain a drag coefficient

f r o m 0. 8 to 1 . 2 between Mach 2 and 3 .

The m o s t significant fact concerning the performance r e su l t s of the P ig -

u r e 11 data is that the drag coefficient values r ema in high as the Mach

number i s increased to 2. 5 and higher. This i s because the isotensoid

design (1) essent ia l ly does not change shape, (2) i s f r e e of coning insta-

bility, and ( 3 ) experiences l i t t le o r no "canopy breathings' a s the Mach


Figure 11 - CD vs Mach Number f o r Large-Size Ballutes

- 48-

T Y P E TEST

1 - T R A C K

2 - WIND T U N N E L

3 - F R E E F L I G H T

NOTE:

A L L C 'S ARE BASED O N B A L L U T E EQUATOR D IAMETER WITHOUT FENCE. F E N C E HE IGHT D

(PERCENT) EQUALS HE IGHT O F F E N C E D IV IDED B Y B A L L U T E EQUATOR D IAMETER x 100.

"O 1 .4

G a 0: O LL 0 k 1 .o z W u LL LL W 0 0 0.6

1 .O 2.0 3.0

M A C H NUMBER

x / d

7.2

. . .

7.0

3.0

7 .0

10.2

6.0

6.0

~ / d

3.00

. . .

3.40

2.04

3.40

3.40

1.23

1.23

M, DE- PLOY

. . .

. . .

2.17

. . .

3.25

. . .

. . .

. . .

1

R E F NO.

42

39

44

47

38

F E N C E HEIGHT

(PERCENT)

10

10

10

10

0

NONE

10

10

SYM- B O L

0 0

a a b

A

T Y P E

TEST

1

2

3

2

3

2

2

2

CONFIGURATION

3 . 7 5 F T D lAM 80-DEG B A L L U T E

4 -FT D l A M GEMINI B A L L U T E

5 -FT D l A M ADDPEP TB-1B

3-FT D IAM GEMINI B A L L U T E

5-FT D l A M A D D P E P TB-2

5-FT D l A M ADDPEP TB-3

4-FT D l A M GEMINI B A L L U T E

22-IN. D lAM A L A R R B A L L U T E

SECTION II - AERODYNAMIC DEPLOY A B L E DECELERATORS GER- 126 16

number approaches Mach 2 . 5 o r higher and with the subsequent a t tach-

ment of the main bow shock to the dece le ra tor .

The plots a r e presented pr imar i ly to show the available documented data

and to give a brief description of the i r meaning. Here again, a s with the

parachute data, a s t ra ightforward analysis of the drag variation a t a given

Mach number cannot be made , since design and performance pa rame te r s

such a s type of model (with var ious fence s i ze s and locations), various

towline lengths, and the actual t e s t conditions vary widely. Other rea-

sons for drag variation a r e that Reference 42 data present drag resul ts behind

anunsymmetr ica l s led, and Reference 38 data present drag resu l t s behind

an unsymmetr ical lifting body. I t i s concluded, therefore , that additional

study o r testing, o r both, will be required to define m o r e completely the

effects of the var ious performance pa rame te r s .

However, based on the presen t available smal.1-size wind tunnel model

data presented in F igure 12, a par t ia l description of how some of the pa-

r a m e t e r s affect the supersonic and hypersonic performances can be given

a s follows:

1. The C D level ( see Reference 49) in f r ee s t r e a m between

Mach 1 , 5 and Mach 2 . 5 var ies between 1.3 and I . 35,

(These resu l t s give useful control-type data and,

coupled with the towed decelerator data, indicate

payload wake effects that lower the C values of D

an 80 deg Ballute to between 0. 8 and 1. 0,)

2. Theoret ical 70-deg and 80-deg apex angle cone-wave

drag values a r e super imposed on the experimental

data to show the general drag t rend with increasing

Mach number. (The genera l t rend of a l l data can be

seen. Note the rapid decay f r o m Mach 1 to Mach 3 -

the upper side of the t ransonic hump - where the de-

tached bow wave becomes an attached and m o r e ob-

lique shock wave with increasing Mach number.)

C [I)

z Y

C K F I

z N CD

+ 2' a

I

4 G 3 3 E 4 CD [I) rr

MODEL CONFIGURATION

1 .O 2.0 3.0 4.0 5.0 6.0 7.0 8.0 9.0 10.0

MACH NUMBER

I


3. Data point 4 shows the CD of the f lexible, coated,

meta l - cloth, 80-deg Ballute without a burble fence

to be 0 .62 a t Mach 10.

Since no explanation of the r e v e r s e t rend ( increas ing C with i nc r ea s - D

ing Mach number ) of the CD of data groups 5 and 6 i s known, this should

be a void a r e a fo r fu r ther considerat ion. F u r t h e r m o r e , the r ea son for

the wide d i spers ion of the d r ag values of the (group 5) 60-deg Ballute i s

not c l ea r ly understood. It was c l ea r that a t a given Mach number a low

q value resul ted in higher C ' s t h a n a t a high q . This would suggest a D

shape change, which i s supported by the fact that this par t i cu la r decel-

e r a t o r configuration was not a n isotensoid design. While the exper i -

menta l data obtained to date utilizing Ballute dece l e r a to r s have been the

m o s t extensive, t he r e a r e s t i l l voids in the avai lable da ta . These

voids consis t of not completely understanding the effects of varying

forebody d i ame te r ra t ios , of varying towline lengths, and of varying

apex angle and fence s i ze (for optimization) over a range of Mach num-

b e r s and Reynolds number s .

F igures 13 through 20 f r o m References 2 , 3 , 26, and 27 p re sen t rep-

resenta t ive resu l t s of wind- tunnel d r a g t e s t s of bas ic blunt-body geo-

m e t r i c shaped dece l e r a to r s . This type of data i s ex t remely useful

s ince i t i s general ly fo r bas ic shapes (cone and sphe re ) , and o ther ex-

per imenta l data and analytical work a r e available to a id in an a e r o -

dynamic evaluation. Because of the r igidity and stabil i ty of these bas ic

shapes , r e a l s t eady-s ta te flow conditions ex i s t ; the re fore , m o r e con-

s tant and valid drag level m e a s u r e m e n t s can be obtained. (Validity,

he r e , means that these d r a g data can be used with a higher l eve l of

confidence in evaluating the type of flow that did occur fo r a given s e t

of t e s t conditions, s ince such varying p a r a m e t e r s a s model change in

shape o r model instabil i ty a r e not p r e sen t to complicate fu r the r a n

a l r eady complex flow pat tern . )

Figu re 13 shows CD var ia t ionwith Machnumber s a t va r ious towline lengths


fo r the s a m e 4 .88- in . d i ame te r , 80-deg apex angle cone behind two

differently shaped forebodies . Based on d r a g values in F igu re 13B,

Schlie r e n photographs, and NACA 1 13 5 flow tables , the following pos tu-

lat ion is presen ted a s a n example of how the local flow affects dece l e r a -

to r per formance :

1. The gene ra l CD d e c r e a s e (a t any of the t h r ee towline

lengths) with increas ing Mach number between Mach

2 and Mach 3. 5 occu r s p r imar i l y because the decel-

e r a t o r bow shock becomes a t tached and m o r e oblique

a s the Mach number i n c r e a s e s . The net r e su l t i s a

lower p r e s s u r e r i s e a c r o s s the shock and hence lower

C va lues . D

2. A t a given Mach number between 2 and 3 . 5 , the CD1s

i n c r e a s e with increas ing towline length. This can be

explained s ince (1) the cone i s positioned in the f a r

wake ( f rom 8D to 12D); (2 ) the inner viscous c o r e has

the s a m e d i ame te r moving af t ; and (3) the inner wake

i s gradual ly mixing with the ou te r wake, the f a r t h e r

af t the dece l e r a to r i s positioned (the c lo se r to f r e e

s t r e a m conditions exis t ) , the higher the CD.

3 . The gene ra l level of d r a g values i n F igu re 13 was

approximately the s a m e ; even though the payload

s i z e and shapes w e r e different , the x /d and D /d l s

w e r e different . The D/d in Curve B was m o r e than

twice the D/d of Curve A. An anticipated higher C D

r i s e r wi th increas ing D/d did not occu r . However,

the physical d is tance af t of the payload was approxi-

mate ly the s a m e , and the s i z e and shape of the decel-

e r a t o r w e r e ident ical i n each ca se , which sugges t s a

wake change with payload shape change.


1.6 2.0 2.4 2.8 3.2 3.6 4.0 4.4 4.8 5.2 MACH NUMBER SOURCE-REF 26

F i g u r e 13 - CD vs Mach N u m b e r f o r 80-Deg Cone


NOTE

The 8D to 12D location i s defined a s the

" far wake, I ' s ince a t this Mach number

range ( 2 to 3.5) , the near wake i s between

3D and 5D, which i s the portion of the

wake immediately aft of the neck and

trail ing shock location. To complete the

definition of the longitudinal wake regions,

the base -flow portion of the wake i s de - fined a s that region ahead of the trail ing

shock (in this case , between 0 and 3D aft

of the forebody).

Above Mach 3. 5, a r eve r se trend in C variation with Mach number and D x/d occurs . In fact, a t Mach 4 . 2 and at an x/d of 8, the CD of 1. 0 i s ob-

tained, which i s the same a s the drag of an 80-deg cone in f r e e s t ream.

F r o m a review of the Schlieren movies, the increasing drag with inc reas -

ing Mach number can be attributed to the following:

1. As the main decelerator bow shock moves aft, the

higher local p res su re immediately aft of the shock

i s nea re r the cone s ides; hence, the higher C val- D

ues a r e obtained.

2. Boundary layer thickness increases with increasing

Mach number; this implies lower local velocities

along the cone s ides , resulting in higher local p res - su res and hence increased C values. (A quantita-

D tive discussion of the boundary layer thickness i s

not possible because of the complexity of the fore - body wake flow that affects decelerator per form-

ance. However, qualitatively the combined effects

at a high Mach number, which consist of (1) higher

energy flow, ( 2 ) varying flow angles (which vary

SECTION XI - AERODYNAMIC DEPLOYABLE DECELERATORS GER- 126 16

local Reynolds and Mach number s ) and (3) complex

shock-boundary l aye r in teract ion (which suggests

turbulent boundary - l ayer conditions along the cone

s ide s ) resu l t i n higher C D values.

The lower CD values with increas ing towline length above 8D a t Mach num-

b e r s above 3.5 can be a t t r ibuted to the divergence of the inner viscous c o r e

aft of the nea r wake region. Although mixing of the inner and ou te r wake

tends to i nc r ea se the local p r e s s u r e s moving aft, the f inal r e su l t i s a de-

c r e a s e i n local p r e s s u r e . One explanation fo r the lowering of the energy

level moving aft i s the effect of the c o r e d iamete r squared. Hence, the 2

t r ansve r se growth ~ ( y ) of the inner co re (with the result ing decreas ing

local p r e s s u r e s ) i s a squared function compared to the l inear i nc r ea se in

longitudinal position aft (x) - result ing in inc reas ing p r e s s u r e and the

subsequent mixing of the inner and outer wake.

F igu re 14 shows the effect of towline length on the C f o r a g r e a t e r range D of x /d l s . The s h a r p drop i n the CD ( s e e F igure 14) a t x /d l s l e s s than 4 i s

due to the divergence of the base-flow portion of the forebody wake because

of the p resence of the dece le ra to r n e a r the forebody. A CD = 0 . 6 i s ob-

tained a s c lose a s an x/d of only 1. This was because the d iamete r of the

dece le ra to r was a lmos t t h r e e t imes the d iamete r of the forebody base ,

causing the flow over the forebody and dece le ra to r to be approximately

the s a m e a s a single forebody - f lare combination. Unfortunately, s ince

the exper imental data i n F igu re s 13 and 14 a r e l imi ted to one s ize of r igid

cone, exper imental data on the effect of s i z e i s a void that wil l r equ i re

future work. In spi te of the data shor tage , a review of F igu re s 13 and

14 revea l s that when the d iamete r ra t io i s s m a l l and the towline length


Figure 14 - vs x/d for 80-Deg Rigid Cone C~


i s sho r t the d rag drops off a s wake effects of the r e v e r s e flow regions ap -

pear . Anticipated higher C ' s with l a r g e r d i ame te r ra t ios did not occur D consistently, which substant ia tes the need f o r m o r e exper imental test ing.

F igure 15 presen ts available C v e r s u s Mach-number data fo r var ious D half-angle cones i n the f r e e s t r e a m . These wind-tunnel d rag r e su l t s r e p -

r e sen t only the nose -p re s su re port ion of the to ta l d r ag . Superimposed on

this f igure a r e the CD levels obtained f r o m the Newtonian flow theory. These

exper imenta l data c lea r ly show the amount of i nc r ea se in C with i n c r e a s - D

ing apex-angle geometry . H e r e again, the void of data above Mach 5 i s

evident. Comparing th is data with to ta l d rag values c lea r ly revea l s that

the ma jo r port ion of the to ta l d rag i s obtained f r o m bow-wave nose d rag

during operation above Mach 1.

In addition to the i r academic value, these ba s i c cone data can be used to

evaluate the per formance of var ious dece le ra to r concepts ( s e e Table I )

a s follows:

1. To fo r ecas t the per formance of the bas ic single

body attached s y s t e m

2. To s e r v e a s "control." data fo r towed cones

F igu re 16 presen ts additional C D data s imi l a r to the F igu re 15 f r e e -

s t r e a m cone data, with the added p a r a m e t e r of spher ica l nose -bluntness

var ia t ion. The data show the nose rad ius of between 1/2 and 1. 0 of that

of the cone base radius . The var ia t ion in C with nose bluntness i s neg- D

ligible.

One of the obvious u s e s of these data i s to exploit a m o r e rounded decel-

e r a t o r to lower the aerodynamic heating level a t a min imum expense of

aerodynamic drag and stabil i ty. With the exception of a few points of data

a t Mach 9 , the void of hypersonic data in F igu re 16 i s evident.

F igu re s 17 and 18 p re sen t towed sphe re d rag data s imi l a r to the F igu re 13

towed cone data fo r 8- and 4- in . -d iamete r s p h e r e s . F igu re s 19 and 2 0

show the i n c r e a s e in C with increas ing sphe re s i ze v e r s u s Mach number D


1.4 I I

N E W T O N I A N T H E O R Y - - - - -

1.2 0 = 50 DEG

4- ---

1.0 -

- -- - 0.8 - 6 = 40 DEG

0.6

0.4

0.2

0 n-

o

M A C H NUMBER SOURCE-REF 2

Figu re 15 - F r e e - S t r e a m Cone Data vs Mach Number

-58-


1 .o

0.8

0.6

0.4

0.2 ==-o ~ / d = 1.69 -.

0

u o I 1.6 2.0 2.4 2.8 3.2 3.6 4.0 4.4 4.8 5.2

MACH N U M B E R

MACH NUMBER

SOURCE-REF 26

F i g u r e 17 - Sphere CD vs Mach Number (8 -In. Model)

- 6 0 -


MACH NUMBER

1 .o

0 .8

0.6

0.4

0.2 ~ / d = 1.45

0 0 0

1.6 2.0 2.4 2 . 8 3.2 3.6 4.0 4.4 4 .8 5.2 M A C H NUMBER

SOURCE-REF 26

F i g u r e 18 - Sphere CD vs Mach Number (4-In. Model)

SECTION 11 - AERODYNAMIC DEPLOYABLE DECELERATORS GER- 126 16

T Y P E 1 SYM- I I I

WT I a I D IAM SPHERE, 3.9 PERCENT F E N C E 1 6 / 1.09

TEST

WT

MACH NUMBER SOURCE-REF 26

B O L

0

W T / a 1 DIAM SPHERE. 3.9 P E R C E N T FENCE

F i g u r e 19 - CD vs Mach Number f o r Sphere behind F l a r e d Body

MODEL CONFIGURATION

4-IN. DIAM SPHERE, 3.9 P E R C E N T FENCE

6 1.45

x/d

6

~ / d

0.73


T Y P E SYM- T E S T B O L MODEL CONFIGURATION x / d ~ / d

W T 0 4-IN. DIAM SPHERE, 3.9 P E R C E N T F E N C E 6 1.69

WT A 6-1,. D IAM S P H E R E , 3.9 P E R C E N T F E N C E 6 2.53

W T 8-IN. DIAM SPHERE, 3.9 P E R C E N T F E N C E 6 3.37

0 . 9

0 . 8

C7 < K 0 .7 0 LL 0 + 0 . 6 z W U

0 .5 I LL SOURCE-REF 26 W 0 U 0.4 1

0 1 .O 2 .0 3.0 4.0 5.0 MACH NUMBER

Figu re 2 0 - CD vs Mach Number f o r Sphere behind Cylindrical Body

-63-


at an x/d of 6. In each figure the expected increase in C with increasing D

~ / d did occur. However, the s imi lar C levels in each figure, in spite of D Figure 20 ~ / d values being over twice the F igure 19 values, suggest the

payload shape also affects the drag -producing capabilities of a given de cel-

e ra tor (see F igure 13). Here again, m o r e detailed work i s required on a

number of payload and decelerator shapes (cones, spheres , Ballutes) to

understand fully how these parameters affect performance.

F igure 21 presents C versus Mach-number data f o r a f r ee - s t r eam sphere. D

These resu l t s were obtained in ball ist ic-range tes t s reported in Reference

30, which a r e in good agreement with wind-tunnel tes t s reported in Refer-

ence 10. The f r ee - s t r eam C level in F igure 21 i s higher than the towed- D

sphere CD level given in Figures 1 7 through 20.

F igure 22 presents the only CD data found f r o m the survey of experiments

above Mach 10. These super-hyper f r ee - s t r eam sphere drag data were

obtained during wind-tunnel tes t s between Mach 11 and Mach 65. Tes ts at

increasing Mach numbers showed increasing C in the transit ion regime D

RCE-REF 30

C D

0 1 2 3 4 5 6 7 8 9 10 M A C H NUMBER

Figure 21 - CD vs Mach-Number for Spheres at Various High Reynolds

Numbers

SE

CT

ION

11 - AE

RO

DY

NA

MIC

DE

PL

OY

AB

LE

DE

CE

LE

RA

TO

RS

G

ER

- 12

6 1

6

Fig

ure

22

- C

orre

latio

n of

Sp

he

re D

rag

Co

effic

ien

ts


between continuum flow and f r e e molecular flow. The CD value of more

than twice that of a sphere below Mach 10 i s significant. This phenomenon

should be exploited, not only to forecas t a more accurate re -ent ry t ra jec-

tory but also to show either a weight saving due to a smal le r -s ize decel-

e ra to r o r improved performance fo r the same size.

d. Attached Nonporous Decelerators - Figure 23 presents available hypersonic C data versus f la re angle f rom D wind-tunnel tes t s of a basic f lared-skir t decelerator configuration. The

significance of these data can be summarized a s follows:

Figure 23 - C vs 8 f o r F lared Body D s

-66-


1. .It 1,s f o r a dece l e r a to r configuration that ha s a l a r g e

ba se d i ame te r i n re la t ion to the payload d i ame te r ,

whi.ch i s d i rec t ly app1.ica.bl.e f o r high d r ag and stab1.e

r e - en t ry and recovery .

2. It can be considered to apply f o r a z e r o towl.ine-

length dece le ra to r .

The available data found in th is survey of the f l a r ed - sk i r t configuration

a r e l imi ted to Mach 8 and to aer0dynami.c models . Si.nce these data a r e

l imi ted to on1.y one Mach number , t h r e e f l a r e angles, and two forebody

s i ze s , additional effort c lea r ly i s requ i red over a wider range of flight

conditions and configuration s i z e s .

Trans ien t and Fluctuating Loads

Compared with the data p resen ted in F lgu re s 5 through 23, considerably

l e s s supe r sonic exper imenta l data a r e available to document t rans ien t

loads during dece le ra to r deployment. T h ~ s data vold can be at tr ibuted

to a bas lc lack of understanding of t h ~ d y n a m ~ c s of the s y s t e m a s wel l a s

to ins t rumentat ion l ~ m i t a t ~ o n s . I n the pas t few y e a r s , the operat ion of

t e s t f ac i? i t i es ha s improved because oi new equipment and improved op-

era t ing procedures . Table XI p re sen t s data fo r represen ta t ive porous

and nonporous deze le ra to r t rans lec t loads d u r ~ n g deployment, inflation

loads , and the fluctuating loads af ter dece l e r a to r lnf3ation. The data In

Table X I w e r e l iml ted to r e su l t s of decelc r a t o r t e s t s that w e r e r e p r e -

sentative and per formed sa t i s fa t t o r ~ l y . Resul ts c o n s ~ d e r e d u ~ s a t i s fac -

to ry w e r e those f o r t e s t s ln whl ih t h ~ models failt-d before data could be

obtained o r the m r a s u r e d osc11lat;ng -load v a r f a t ~ o n was nea r o r m o r e

than 100 percen t of the mean load.

All t e s t s used a t ens iomete r , located lr, the r ~ s e r 1jrLe between the payload

and the towed dece l e r a to r , t o rneasurc the- lnstantaneous t rans ien t and

s teady-s ta te loads . In each of the 15 tc;st s shown :n Table XII, the decel-

e r a t o r was forcibly deployed f r o m ~ t s stowed position in a payload by

e i ther a pyrotechnic o r a sp r ing - th rus t i ng mechanism, F o r such t e s t s ,

SECTION II - AERODYNAMIC DEPLOY ABLE DECELERATORS GER- 126 16

the stowed decelerator is held in i t s packed condition in a deployment bag

a s i t moves aft to the " l ine-stretch" condition. At this t ime, the "snatch

load" occurs a s the fully extended r i s e r line causes the decelerator to

slow down to the speed of the payload; the deployment bag i s re leased

f r o m the decelerator , and the decelerator being to inflate. Usually at

the instant of full inflation, the opening -shock load occurs . If the sys - t em operates a s designed, the opening-shock load i s the peak load that

decelerator feels during i ts operating life. Since this opening -shock

load must be known so that s t ruc tura l strength can be designed into a de-

ce lera tor system, the lack of this type of experimental data i s a major

void in the s tate of the a r t of dece lera tors .

Table XI shows that the peak load during deployment was the opening-

shock inflation load in a l l but two tes t s . Of these exceptions ( test i tems

6 and l o ) , l ine-f i rs t deployment did not occur since the deployment bag

inadvertently was released f r o m the decelerator and the decelerator began

to inflate before line s t re tch occurred. This resulted in loads due to snatch

that were higher than the opening shock loads.

The significant resul ts of the Table XI1 tes t data can be summarized a s

follows ;

1. The Ballutes a r e essentially f r e e of breathing and

coning.

2. The parachutes experience breathing and coning.

3 . The decelerators that had longer filling t imes ex-

perienced lower opening-shock loads.

4. Data a r e available that demonstrate successful

deployment and inflation of both textile and metal

cloth models.

Wind-tunnel tes t examples of the levels of parachute and Ballute breathing

and coning o r the lack of i t a r e given in Figures 24 through 27. Figures

2 4 and 25 present data obtained with two types of recording equipment.


TABLE XI1 - DECELERATOR TEST RESULTS

Transient opening conditions 1 I

: * 67-B

6 4-A pl -

Model and

Descrip- tion

Hyperflo, 4-ft D~

Hyperflo, 4-ft Do

Hyperflo, 4-ft D~

Parasonic, 4-ft Do

Hyperflo, 2.72-ft D~

Hyperflo, 3.69 Do

Gemini Ballute 3 - ft diam

Parasonic, 4-ft Do

Hyperflo, 4-ft Do

Parasonlc, 4-ft Do

ADDPEP Ballute 5-ft diam

ADDPEP Ballute 5-ft dlam

Hemisflo, 4.12 Do

Parasonic, 5 .5 Do ADDPEP 5.: F t d ~ a m Ball~i te

+Types of

condition

M

2.6

2.6

2. 5

2.6

2. 6

2. 2

2. 59

2.2

2.6

2.6

3.01

3.42

2 8

F F =

tes t

Type of *

t e s t

WT

WT

WT

WT

WT

WT

WT

WT

WT

WT

WT

FF

F F T

WT

W T

test .

q (psf)

120. 4

120.6

119. 7

120.0

120. 0

249.0

120.7

120.0

120.3

120. 1

120. 5

140.0

120

f ree

Average load (lb)

328

331

385

186

702

729

401

241 to 3 06

383

1942

720

1675

Shock factor -

Y

2. 13

2. 42

1.46

5. 00

1.78

1.37

1.62

2.74

2.13

. . .

0.66

2.35

B

load

Type of reading

Oscillo- graph

Oscillo- graph Osclllo- graph

Oscillo- graph

Oscillo- graph Oscillo- graph Oscillo- graph

Beck- m a n

Beck- m a n

Beck- man

Beck- man Oscillo- graph

Tele- m e t r y

Oscillo

tunnel

Load (1b)

550

500

120

2100

450

470

1110

600

1340

890

1200

. . .

2175

flight, WT

Reference

AEDC-TDR- 64-120

AEDC-TDR- 64-120

AEDC-TDR- 64-120

AEDC-TDR- 64-120

AEDC-TDR- 64-120

AEDC-TDR- 64-120

AEDC-TDR- 64-120

AEDC-TR- I 65-57

GER-11665

wate r vapor.

Snatch

Tlme ( sec )

. . . . . .

. . . . . . 0. 02

0.008

0.05

0.02

0.02

0.02

0.007E

0.055

0.11

0.235

0 . 2

= wind

Steady-state

Load fluctu- ation f rom

average, A (lb)

. . .

. . .

. . .

. . .

f 30 to + 60

t 192 to + 375

t 50

t 120 to * 270

120 to 240

* 36 t o * 216

* 36

180

'Filling tlme

Load (lb)

700

800

562

930

1250

1000

650

746

815

1600

4880

"-f

Model ref-

erence desig- nation

H-1

H-2

H-3

H-7

(SP-3)

H-8

H-12

. . .

H-1 (SP- 3A)

H-3

H- 5 (SP-7)

TB- 1B

Remarks

A,/A, = 3 20; suspension llne falled a f t e r 3 m i n

A /A = 4.20; suspension line failed a f t e r 2 hi:

At t = 0.21 s e c , load = 440 l b + 250; a t t = 0 .55 sec , load = 440 lb + 100. Con- figuration falled a t t = 4' m i n ( A ~ / A ~ = 3.75)

Model in tunnel 22 min

Model in t u ~ e l 28 m m

Model spinning occurred a f te r Inlet cord failed; model in tunnel 23 min; no conlng

A /A = 3.62 ~ ' o o f ?ailed

A~/A,= 4.3

A~/A, = 4. 7

Ballute TB-3 (unpublished PWT tes t s 12/64, no coning

NO faiIGG aui ing T s t m l g r - temperature, metal- cloth Ballute

Opening

T ime ( sec )

. . . . . . . . . . . . 0. 07

0. 1

0. 19

0.21

0. 11

0.075

0. 18

1.34

. . .

. . . . . . . . .

loads

Fluttering frequency

(cps)

5 0

80

80

8 0

8 0

accelerated by

Coning frequency

(cps)

0

8.9

8 0

8. 95

0

alcohol and

load

Filling t lme (sec)

. . . . . .

. . .

. . . . . .

. . . 0. 17

0. 19

0. 09

0.0675

0.125

1.0

1 .0

0 65'

J

Type reading

Oscillo- graph

Oscillo- graph Osclllo- graph Oscillo- graph

Oscillo- graph Oscillo- graph Oscillo- graph

Beck- man

Beck- man

Beck- man

Oscillo- graph


F i g u r e 24 - 5. 5 - F t Do Pa ra son i c (Oscil lograph - Instantaneous Load vs

T ime) ; See Table XI, I tem 14

F i g u r e 24 data was obtained with an osci l lograph r e c o r d and F igu re 25

data obtained with a Beckman ins t rument . Beckman ins t ruments a r e

m o r e accura te fo r measu r ing nea r instantaneous load values than the

osci l lograph. However, the Beckman r e c o r d s data fo r ve ry sho r t pe r i -

ods. The oscil lograph can r e c o r d the data continuously and a l so indi-

cate such sequences a s deployment initiation and movie c a m e r a s t a r t .

The oscil lograph r e c o r d a l so can be r ead immediately. after it r e c o r d s ,

while the Beckman data m u s t be reduced. This data reduction takes

hou r s .

These t r a c e s of the actual r eco rds indicate the deg ree canopy breathing

(amplitude and f requency) . In addition, the high peaks that occur eve ry

0 . 2 s e c indicate the re la t ive degree (amplitude) of coning. This data i s

supposedly "steady-state1' data . F i g u r e 26 p r e sen t s Beckman r e su l t s of

a 4-f t Do Hyperflo.



F i g u r e 25 - 5 . 5 - F t Do P a r a s o n i c (Instantaneous C vs T ime) ; See

Table XI, I t em 14 Do

I

0.6

0.5

0.4

0.3

0.2

0.1

no

0 0.2 0.4 0.6 0.8 1 .O TIME (SECONDS) .

F i g u r e 26 - 4 - F t Do Hyperflo (Instantaneous C v s T ime) ; See

Table XI, I tem 9 Do


Figure 2 7 - 3 - F t Diameter Ballute, Load vs Time (See Table XI, I tem 7)

F igu re 2 7 a lso presents a t r a c e of the actual oscil lograph r eco rd of Bal-

lute t e s t loading variation encountered. Note the relatively smooth t r a c e

af ter model inflation indicating negligible breathing and coning. After

model inflation, the relatively smooth t r a c e i s under a s teady-sta te con-

dition.

5. AERODYNAMIC STABILITY

a . General -

F o r the purpose of determining stability, aerodynamic dece le ra tors can

be broadly classified into two categories . The f i r s t category includes

those that a r e attached to the payload, the second includes those that a r e

towed behind the payload. F o r an attached decelerator ( f lares , extended

f laps , etc. ) , the cur ren t airplane -type s ta t ic and dynamic coefficients

a r e adequate for determining stability; however, these coefficients do


not appear adequate for a towed decelerator , because of the complex flow

field that it separates and the towline influence.

b. Attached Decelerator System - Goodyear AerospaceP s survey determined that there is no documented,

quantitative, experimental dynamic-stability data available for any con-

cept shown in F igure 3 . The only stability data found were s tat ic s t a -

bility data for a cone o r f la red skir t .

Extensive wind-tunnel t e s t s have been run on f la red bodies; however,

most of the data f rom these t e s t s a r e applicable only to f l a re s with smal l

f l a re angles, which a r e intended "to be used to stabilize re -ent ry bodies

and miss i les . Most of these experimental data were considered unrelated

to f la red sk i r t s used a s decelerators . Only three wind-tunnel tes t s ( see

References 51, 52, and 53) present data f o r f l a re s of sufficiently la rge

flai?e angles and frontal a rea .

Reference 52 shows that s ta t ic stability i s reduced with flare-angle in-

c rease and that stability r i s e s with forebody-lcngth increase, a s f la re -

to-forebody frontal a r e a i s held constant.

Reference 51 shows that s ta t ic stability i s reduced a s f l a re angle increases ,

with f l a re length held constant, for both conical and hemispheric nose fo re -

bodies; stability i s increased with forebody elongation and flare-angle in-

c rease , as f la re length i s held constant.

Apparently, there i s a complete void in experimental dynamic stability

data of f lared bodies.

Towed Decelerator System

Information previously has been limited to visual observations of decelera-

t o r s under towed conditions. The only data available to date on devices

that might be considered towed decelerators a r e dynamic and s tat ic co-

efficients of these devices sting mounted under f r e e - s t r eam conditions

( s e e F igures 2 8 and 29) .


Static stability variation with Mach number for cone semiapex angles

f r o m 20 deg to 50 deg i s shown in F igures 28 and 29. These curves a r e

based completely on experimental data at smal l angles of attack f rom cg

References 2, 4, 5, 6 , 11, i12, and 74 through 77. C i s shown to be NO

positive and increases with the cone half angle; the s ta t ic center of p res -

su re moves rearward , indicating that cones with large apex angles a r e

ve ry stable statically. The distance f rom the cone apex to the s tat ic

center of p res su re f rom Newtonian theory ( see References 11 and 74) is

2 2 X C P = ~ ( 1 t t a n ~ ~ j ~ w h e r e i i s t h e c o n e l e n g t h .

The damping capability of either a ball ist ic or lifting vehicle i s greatly

affected by C , which i s important to the damping of the longitudinal La

short-period mode ( see Rkference 5) . Both iheory and experiment show

that, as cones become shor te r (high 9 ) , the l if t-curve slope decreases s

until it reaches ze ro at 8 = 45 deg. At higher semiapex angles, C S

negative.

Although stability i s well defined statically, l i t t le is known f r o m dynamic-

stability tes t s . References 4, 74, and 77. present damping charac ter i s -

t ics for cones at very low speeds and at Mach 6. 8 (hypersonic).

Reference 74 presents resu l t s of comprehensive stability wind-tunnel

t e s t s on a cone of 0 = 12.5 deg at Mach 6. 8 and the damping moment S

coefficient derivative t ransfer equation

where subscript 1 r e fe r s to the longitudinal position about which the damp-

ing coefficient derivative is desired, subscript 2 ref e r s to the longitudinal

position about which all of the above coefficient derivatives a r e known,

and subscript 1-2 r e fe r s to the longitudinal distance between the r e spec -

tive points.

SECTION 11 - AERODYNAMIC DEPLOYABLE DECELERATORS GER-126 16

Where

CM = pitching moment coefficient, M / ~ ~ s ~

CN = force coefficient normal to body axis, N / ~ ~ s

X = longitudinal distance

Q = body length and/or reference length

q = pitch ra te

900 = f r ee - s t r eam dynamic p res su re

V = velocity 2 S = projected a r e a ( ~ / 4 d )

d = reference diameter.

Three se t s of data were taken about three different centers of moment.

Since data f rom two centers of moment a r e required, this tes t provides

three se t s of moment data for equation ( 2 ) for t ransferr ing C M q

+ CM. to any other moment center.

These were used to make a t r iple check of % about the cone base. q CY

Correlation was very poor and i s not presented here . Either smal l e r r o r s

in the t e s t data a r e magnified by the t ransfer equation (2) o r , as i s sus-

pected, the equation i s incorrect for la rge moment- t ransfer distances be - cause of the assumption that C i s invariant with moment center. A N

q


Figure 28 - CN vs Mach Number for Cones

LEGEND: CODE NO. - SANDIA SC-R-64-1311, FOSTER (FROM CONVAIR ZA-7-0?7, GENDTNER, 0 0 = SEMIAPEX ANGLE AND MARSHALL SPACE FL IGHT CENTER MTP-AERO-61-38)

a NASA T N D2624, MAYO, ETC. (NEWTONIAN1 . @ c z - dCN

0 NASA MEMO 2-22-59L, L ICHTENSTEIN, ETC. 0 Na Ja

A NASA T N 3788, TOBAK AND WEHREND (NEWTONIAN) 0 C =N NASA TN 0-2283, PENLAND 0 N 1 2 T P v

0 NASA T N D.17M1, WEHREND 0 2 n D

I

CHANGES

A 10 DEG(.~

20 DEG A

V J P L TECHNICAL REPORT NO. 32-74qMARTE AND WEAVER 5 = -

4 2.0

-# -u

- -- -n

,, 4 -- 1.5

-- --El

- u

w 0

V) ----•

W

.

0

0

J

I 0

40 DEG

A

DEG <.I A

60 D E G ~ ~

10 20 0 0.5 1 .O 1.5 2.0 2.5 3.0 3.5 4.0 6 8 MACH NUMBER

I

,

SCALE

SECTION LI - AERODYNAMIC DEPLOYABLE DECELERATORS G E R - 126 16

Preceding page Mank 79-fi Figure 29 - cp vs Mach Number for Cones

20.0

!

@ s 50 DEG <

40 DEG<

30 DEG<

- 20 DEG<

10 DEG<

10.0 - SCALECHANGES

8.0

2.4

2.2

2.0

1 .8

1.6-

1.4

1.2

- 1 .o \

w' LT

8

\

LEGEND:

- SANDIA SC-R-64-1311. FOSTER (FROM CONVAIR ZA-7-017, GENDTNER, AND MARSHALL SPACE FLIGHT CENTER MTP-AERO-61-38)

a NASA TN 04624, MAYO, ETC. (NEWTONIAN)

0 NASA MEMO 2-22-59L, LICHTENSTEIN, ETC.

NASA TN 0-2283, PENLAND

0 NASA TN D-1766, WEHREND

V JPL TECHNICAL REPORT NO. 32-743, MARTE AND WEAVER

Bs = SEMIAPEX I ANGLE 1 I

---a

-0

6.0

1 CONE LENGTH /

i 3.0 MACH NUMBER

g 0.8-

IL

0 0

0 0.6. 3.5

,-

- - --

4.0 0.5 1 .O 1.5 2.0 2.5

0

---El

-'O

-- 4

X = DISTANCE ALONG AXIS OF SYMMETRY

I

20 DEG

10 DEG

- -.

-

1

1

0 Bs = 33.3 DEG 30 DEG

SECTION 11 - AERODYNAMlC DEPLOYABLE DECELERATORS GER- 126 16

brief attempt to verify this la t ter suspicion failed. The test data der iva-

t i v e s f r o m R e f e r e n c e 5 a n d t h e N e w t o n i a n e x p r e s s i o n s f o r C a n d C N q NCr

f r o m Reference 11 were used to calculate three values for cn/r- t C q

about the base. Correlation was poor.

Reference 11 i s a collection of various theories for estimating sthtic - and

dynamic -stability derivatives of simple axisym-metric bodies. Potential

flow theory, f i r s t -o rde r and/or second-order l inear theory, slender-body

theory, and Newtonian impact theory were a l l used to determine the s t a -

bility derivatives.

The cone f r e e - s t r eam stat ic - and dynamic -stability data presented a r e

not representative when the decelerator i s trailing the payload and is op-

erating in the flow regime that i s generally classified a s a wake. The

decelerator , being placed in this flow regime, becomes an object of i ts

environment and at the same time by i t s physical presence influences

this very regime. Qualitative and quantitative propert ies of this regime

will completely define the performance and subsequently the design of a

decelerator if it i s immersed in the flow downstream of the payload.

Tes ts have indicated, for example, that when a towed cone has an apex

angle of more than 90 deg, i t becomes unstable.

d. Wake Effect on the Decelerator -

Essentially, the problem of determining the interaction effects between

the wake and a decelerator immersed within i t would be no different f r o m

any problem of a body immersed in a flow, provided the flow propert ies

a r e known. Unfortunately, this i s not the case , since the wake flow has

specific complicated propert ies . In addition, the proximity to the body

creating the wake, plus the fact that the body and decelerator a r e con-

nected by means that a r e subject to the laws of rigid mechanics, intro-

duces complexities that require sophisticated and rigorous analysis .

As previously indicated, lack of experimental data make i t impossible to

. verify theoretical wake models by experiment. Thus, the i.nteraction car1



a t bes t be descr ibed in hypothetical t e r m s . If interaction i s approached

by the principle of the momentum defect, and the ini t ia l conditions a t the

forebody base a r e known, i t can be postulated that the growth of the wake

depends on the skin f r ic t ion of connector and r i s e r l ines.

In accordance with Prandt l ' s concept of viscous flow, and assuming that

local acceleration in the inner wake i s m o r e pronounced than acce l e ra -

tion due to an external p r e s s u r e gradient, the momentum integral equa-

tion can be expressed by ( see Reference 78)

where

/' = a i r density,

9 = momentum thic kne s s ,

a = wake thickness,

r = radial coordinate,

u = velocity in x direction,

C = constant with respect to x , and X

1 = wake edge location.

To satisfy the conservation of momentum:

where B equals conditions at the base, and d equals the body diameter .

If the above postulate i s t rue , a par t icular decelerator configuration and

a par t icular forebody will exhibit only slight variations in drag coefficient

at ce r ta in x/d locations and a constant Mach number. If Figure 30 i s con-

s idered representat ive, this concept i s apparently valid for

SECTION I1 - AERODYNAMIC DEPLOYABLE D E C E L E R A T O R S GER-12616

F igure 30 - D r a g vs x/d, Hyperflo Model 1 behind Forebody Type I

-83-

1.2

1 .o

0.8

0.6

0 .4

0 0

U

i z w 0 .2

u_ LL LL

W 0 U 0 4 II:

0

M~ = 5 . 5

- M-=5i5'

6 7 8 9 10 11

DOWNSTREAM STATION, x/d

SOURCE-REF 79


and f o r

a t

F igure 31 shows the C D var ia t ion v e r s u s parachute downstream location

x/d a t t h r ee Mach numbers , due to the momentum "defect" influence of

two different forebody shapes .

F igu re 32 i s r epresen ta t ive d rag data of another parachute model in a wake

that i s a r r anged to show the effects of Mach number on the C D a t two down-

s t r e a m dece le ra to r locations.

In genera l , f u r t he r and m o r e detai led evaluations of the flow field, p r e s -

s u r e distr ibution, e t ~ . , a r e c lea r ly required. Specifically, evaluations

of the fluid dynamics p rope r t i e s such a s shock-wave/wake in teract ion,

shock/boundary l a r g e r in teract ion ( in the wake behind the payload and

in f ron t of the dece l e r a to r ) , and separa ted flow due to the p resence of

the r i s e r l ine and a t tachments in the wake a r e requ i red .

A detai led discuss ion of wake data found during the survey i s given in

Refe rence 8 0 .

Because of the dynamic t ime-dependent p roper t i es of the forebody wake

acting on the towed dece l e r a to r in this wake, c u r r e n t acceptable dynarnic-

and s ta t i c -stabil i ty coefficients do not appear adequate to desc r ibe the

motion of the dece le ra to r . The only information on stabil i ty of towed

dece l e r a to r s is f r o m v i sua l observat ion of the degree of stabil i ty.

SECTIONII - AERODYNAMIC DEPLOYABLE DECELERATORS GER-12616

SOURCE-REF 79

0.8

0.6 U

0 U

i z '!?

0.4

LL W 0 U (3 u II: 0 0.2

4 6

M A C H N U M B E R

. Figure 32 - Drag vs Mach Number, Hyperflo Model 2 behind Forebody Type I

References 27, 40, and 57 use relative descriptive t e r m s such a s excel-

lent, good, f a i r , and poor. Since this type of reporting does not describe

adequately the motions that define stability character is t ics , more vigor -

ous future test-condition c r i t e r i a and test-reporting procedures a r e

needed to acquire this necessary experimental information.

The following a r e examples of the motions that need to be described and

have c r i t e r i a applied to them:

1. Single -mode pendulum motion (rigid towline)

a. Pitch-angle displacement and pitch rate about attachment point

b. Roving-angle magnitude (pitch and yaw) and roving ra te

c. Roll angle and rol l ra te

2. Two-mode motion - combined inflation-shape change and

single -pendulum mode (amplitude and frequency)

3. Multimode motion - superimposing flexible towline motion

on I tems 1 and 2 , above

SECTION I1 - AEROD'YNAMIC DEPLOYABLE DECELERATORS GER-12616

a . Genera l - The types of ae ro thermodynamic loading and some methods fo r e s t i -

mating the hea t load a r e de sc r i bed below

In genera l , the u se of a dece l e r a to r during re -en t , ry o r r e c o v e r y of a

s y s t e m in the flight r e g i m e of ~ n t e r e s t , r equ i r e s a near - ins tan taneous

deployment to augment the s y s t e m d r a g c h a r a c t e r i s t i c s . Th is de-

ployment usually l eads to the exposure of su r f ace s that a r e subjected

to sudden ae rodynamic heating, leading to a n immedia te buildup of the

local heating r a t e s with e i the r ( 1 1 a rapid decay f r o m the instantaneous

max imum local heating r a t e o r ( 2 ) a m o r e g radua l decay , depending on

the type of device used and the a l t i tude , velocity, and d i rec t ion of mo-

tion a t which deployment was in i t i a ted . 'The p rob lem of defining these

local heating rat .es i s compounded because some of the m o r e bas ic de -

c e l e r a t o r s such a s pa rachu tes , Ba l lu tes , and inflated s k i r t s genera te

flow fields that a r e inherent ly cha r ac t e r i s t i c of t.he device i t se l f .

The re fo r e , the de te rmina t ion of the loca! heating r a t e s and the deg ree

of t e m p e r a t u r e r i s e to de t e rmine m a t e r i a l applicabil i ty become a

function of the s y s t e m operat ion and if.5 deployment r equ i r emen t s , a s

well a s the ae rodynamics of the flow f ie ld .

The following suggested methods can be and have bec,n used to ca lcula te

the loca l h e a t ~ n g loads F o r example the hea t - t r an s f e r c h a r a c t e r i s t ~ c s

of a n inflatable s k l r t or f l a r e car1 be evaluated if the type of flow over

these c a n be predicted. F o r att.ached flow heat - t r an s f e r r a t e s fo r

e i the r l amlna r o r turbulent flow can be calcula ted by uslng established

hea t - t r an s f e r theory; f la t -p la te h e a t - t r a n ~ f e r equations uslng local flow

conditions can be used . how eve^ fo r s epa ra t ed flow, the calculat ion

of the hea t t r a n s f e r r a t e s becomes m o r e complex. In the p a s t , the data

in Refe rences 5 2 and 8 1 have been 1:5ed t o e s t lma t e the hea t - t r an s f e r

c h a r a c t e r i s t i c s f o r s epa ra t ed flow When the dece l e r a to r IS at tached

o r f o r m s a n in tegra l pa r t of the r e - e n t r v o r r e cove ry s y s t e m , the


predic t ion of the local heating r a t e s cons i s t s of applying usual ly r e - l iable hea t - t r an s f e r theory t o e s t ima t e hea t t r a n s f e r coefficient.

Other conlrrlon types uf dece l e r a to r s a r e the parachute and , m o r e r e -

cen t ly , the Ballute. These dev ices a r e usual ly deployed In the wake

of a leading body. The predic t ion of the heating loads r e q u l r e s a n

unders tanding of the wake and i t s fo rmat ion . The determinat ion of the

p rope r t i e s of the wake behind a n object moving i n a fluid medium i s

one of the oldes t and m o s t bas ic p rob lems of fluid mechan ics . Al-

though theore t i ca l solutions ex i s t f o r both l amina r and turbulent in-

compre s s ib l e wakes , the extension of these solutions to high Mach-

number compre s s ib l e -wake phenomena ha s not been complete ly suc -

cess fu l . A s a consequence, l i t t le at tention ha s been given to the wake

phenomena with r e g a r d to ae rodynamic deployable dece l e r a to r s t ra i l ing

in the wake of a leading body.

Although cons iderab le exp lora to ry work has been per fo rmed and docu-

mented dealing with the aerodynamic per fo rmance of d e c e l e r a t o r s

t ra i l ing in the wake of a leading body and a s soc i a t ed component p e r -

f o rmance , such a s in Refe rences 26, 27, 54, and 82, only l imi ted ef-

f o r t ha s been ini t iated to evaluate the t h e r m a l l imi ta t ions and pe r fo r -

mance of such dev ices . The da ta contained in these r e p o r t s w e r e

or iented p r i m a r i l y toward evaluating parachu tes and balloon-type a e r o-

dynamic d e c e l e r a t o r s , with emphas i s on d r a g c h a r a c t e r i s t i c s . In

pa r t i cu l a r , Refe rence 27 documents the in i t ia l ef for t devoted to both

theore t i ca l and exper imenta l ana lys i s of the hea t - t r an s f e r c h a r a c t e r -

i s t i c s of a dece l e r a to r t ra i l ing in the wake of a leading body. Th is

in i t ia l ef for t t e rmlna ted with the compilat ion of a s e r i e s of des ign

c u r v e s ( s ee F i g u r e s 3 3 through 36) that aided in de te rmin ing hea t -

f lux- ra te d is t r ibut ion over two di f ferent dece l e r a to r configurations and

the cor responding radia t ion equ i l ib r ium- tempera tu re d is t r ibut ion over

these bodies . The des ign c u r v e s published in Refe rence 1 w e r e ba sed

on a single exper imenta l ly de te rmined hea t - t r a n s f e r d is t r ibut ion over


S - DISTANCE FROM STAGNATION POINT , F T

R - RADIUS, F T 0

;I - LOCAL H E A T FLUX, BTU/HR-SQ FT

4O - H E A T F L U X A T STAGNATION POINT WITHOUT FOREBODY, BTU/HR-SQ F T

T - L O C A L TEMPERATURE, DEG R

T - TEMPERATURE A T STAGNATION P O I N T WITHOUT O

FOREBODY OR I N T E R N A L RADIAT ION, DEG R

F i g u r e 3 3 - Heat F lux and T e m p e r a t u r e Dis t r ibut ion on a Sphere L a m i n a r Flow


S - D ISTANCE FROM STAGNATION POINT , F T

R - RADIUS, F T 0

6 - L O C A L H E A T F L U X , BTU/HR-SQ F T

G c - H E A T F L U X A T S/R = 1 WITHOUT FOREBODY, BTU/HR-SQ F T 0

T - L O C A L TEMPERATURE, D E G R

T - TEMPERATURE A T S/R = 1 WITHOUT FOREBODY, DEG R C 0

1.4

1.2

1 .o

0.8

0.6

0.4

.WU 0.2 \ . 5

0 0.5 1 .O 1.5 2.0 2 .5 3.0

S/ Ro

1.1

1 .o

0.9

0.8

0.7

0.6

+(' 0.5 \ + 0.4 1 1

0 0.5 1 .O 1.5 2.0 2.5 3.0

S/ Ro

Figu re 3 4 - Heat F lux and Tempera tu r e Distr ibution on a Sphere Turbulent Flow

- 9 0 -


S - D I S T A N C E FROM S T A G N A T I O N P O I N T , F T

R - NOSE RADIUS, F T 0

4 - LOCAL H E A T FLUX, BTU/HR-SQ FT

qo - H E A T F L U X A T S T A G N A T I O N P O I N T WITHOUT FOREBODY, BTU/HR-SQ F T

T - L O C A L T E M P E R A T U R E , D E G R

T - T E M P E R A T U R E A T S T A G N A T I O N P O I N T WITHOUT F O R E B O D Y , DEG R 0

1 .o

0.8

0.6

0.4

0.2

.a0 \ .a

0 2 4 6 8 10 12 14

S/ RO

1 .o

0 .8

0 . 6

0 .4

0 + \

0.2 0 2 4 6 8 10 12 14

S / R o

Figu re 35 - Lamina r Heat Flux and Tempera tu r e Dis t r ibut ion o n a Blunted Cone


S - DISTANCE FROM STAGNATION POINT, F T

R - NOSE RADIUS, F T 0

6 - LOCAL HEAT FLUX,BTU/HR-SQ FT

qc - HEAT FLUX A T S/R = 2 WITHOUT FOREBODY, BTU/HR-SQ FT

0

T - L O C A L TEMPERATURE, DEG R

T - T E M P E R A T U R E A T s /R = 2 WITHOUT FOREBODY, DEG R C 0

U -tr \ .6

0 2 4 6 8 10 12 S/ Ro

1.2 I I 1 WITHOUT FOREBODY

& &*-'y \

0 . 8 r c A.

\--- ----. --'T,,H FOREBODY '< 0.4

0 I N T E R N A L RADIAT ION NOT INCLUDED k \ k

0 2 4 6 8 10 12

S/ Ro

Figure 3 6 - Turbulent Heat Flux and Tempera tu re Distribution on a Blunted Cone

-92 -


a Ballute body a t Mach 10. Apparent ly , t h e s e c u r v e s can s e r v e a s

p r e l i m i n a r y des ign guides f o r u s e in r e c o v e r y - s y s t e m appl ica t ions

s u c h a s those c o n s i d e r e d in th i s s tudy.

Addit ional f l igh t - t e s t d a t a and t h e o r e t i c a l approaches w e r e outlined

i n Refe rence 80 with l imi ted t h e r m a l c o r r e l a t i o n c o r r e s p o n d e n c e .

The r e s u l t s of the l a t t e r w e r e d i r e c t e d p r i m a r i l y toward d e c e l e r a -

t o r s opera t ing i n the superson ic flow r e g i m e . T o gain a b e t t e r

unders tanding of wake fo rmat ions and the i r effect on t r a i l ing de -

c e l e r a t o r s , Goodyear A e r o s p a c e conducted a n in-house study of

s u p e r sonic wake phenomena a s s o c i a t e d with Ballute -type d e c e l e r a -

t o r s . T h e s e s tudies w e r e p r i m a r i l y concerned with c o r r e l a t i n g the

exper imen ta l Mach 10 wind-tunnel r e s u l t s with a theore t i ca l approach

of a m o r e exac t n a t u r e than tha t used in e s t ima t ing the des ign c u r v e s

shown in F i g u r e s 3 3 through 36 . The r e s u l t s of t h e s e s tud ies w e r e

published in R e f e r e n c e s 83 and 84 . In t h e s e s t u d i e s , a s imple model

of a wake flow based on the in te rac t ion between the leading body and

the t ra i l ing d e c e l e r a t o r was f o r m u l a t e d , and engineer ing methods

w e r e developed fo r predic t ing p r e s s u r e and h e a t - t r a n s f e r d i s t r i b u -

tion over Ballute d e c e l e r a t o r s u r f a c e s . Both l a m i n a r - and turbulent -

flow wake phenomena w e r e c o n s i d e r e d .

b . Equat ions - At p r e s e n t , the type of wake can b e e s t i m a t e d by using the t r a n s i -

t ion da ta fo rmula ted in Refe rence 85. F o r l a m i n a r flow, a g e n e r -

a l ized equation developed in R e f e r e n c e 83 f o r the r a t i o of the hea t -

t r a n s f e r coefficient on a d e c e l e r a t o r i m m e r s e d in a wake t o a heat -

t r a n s f e r coefficient fo r a cone without the p r e s e n c e of a leading body

w a s d e r i v e d a s follows:


h h

cone

where

h = heat t ransfer coefficient, ~ t u / h r - s ~ ft-deg F, o r

h = equivalent cone heat t ransfer coefficient, Btu/hr -sq cone ft-deg F,

c = specific heat of a i r (24 Btu/lb/deg) P

P' = local pressure , psf

P = equivalent cone pressure , psf, cone

P = f r e e - s t r e a m pressure , psf, 00

r ' = local radial coordinate, f t ,

S = local distance f r o m apex, ft ,

S' = local distance along Ballute meridian surface f rom equator 'd iameter , and

D = decelerator diameter , f t .

This expression was found generally to be in good agreement with the

only experimental data available - that contained in Reference 27. A

typical correlation is shown in Figure 37.

The turbulent heat- t ransfer distribution over a Ballute-type decelerator

immersed in the wake of a leading vehicle also was formulated in Refer-

ence 83 in a manner s imi lar to that used for the laminar -flow case. The

resulting generalized heat t ransfer coefficient equation was formulated

as:

h = p 'u ' c P r P

where

- 94 -


F igu re 3 7 - Mach 10 Ballute Hea t -T rans f e r Resu l t s


P' = loca l densi ty , pcf,

u ' = loca l velocity, f p s ,

c = specif ic hea t a t constant p r e s s u r e , ~ t u / l b - d e g F, P

P r = Prand t l numbe r ,

C f ' = loca l f r i c t ion coefficient ,

(S) = local f o r m f ac to r , d imens ion less , and

h = hea t t r a n s f e r coefficient, ~ t u / s ~ f t - s ec -deg F.

The p r i m e s in th is equation indicate that the p rope r t i e s of the flow

m u s t be evaluated a t the dece l e r a to r su r face o r a t the edge of the

dece l e r a to r boundary l aye r .

P rac t i ca l ly no exper imenta l o r f l ight- tes t data ex i s t to compare with

the theoret ica l ly der ived exp re s s ions . Thus , th is l a rge ly unexplored

a r e a suffers g rea t ly f r o m the lack of high-quality exper imenta l data

to ver i fy the predic t ion methods desc r ibed in Refe rences 83 and 84.

However, the use of the developed express ions appea r s to be just i-

fiable s ince the flight t e s t data obtained thus f a r , although of an ex-

p lo ra to ry na tu re , have not indicated s e v e r e o r undcrpredic ted a e r o -

dynamic -heating p rob l ems .

The expected t empe ra tu r e r i s e of parachute dece l e r a to r s in the high

supersonic -speed reg ime i s another si tuation that will r equ i r e an ex-

plorat ion of the wake and i t s in teract ion with the flow field before a

predic t ion can be made . The use of a porous roof , e i the r of a fine

m e s h or ribbon const ruct ion, ha s p resen ted a f low-predict ion prob-

l e m that ha s not been resolved in the parachute-des ign field. Since

the individual components of such parachu tes can be composed of

m a t e r i a l s of re la t ively low m a s s (and hence, low hea t capaci ty) , they

a r e subjected to s e v e r e aerodynamic heating. The explora tory f l ight-

t e s t data p resen ted in Refe rence 5 4 shows that su r face t empe ra tu r e s


of 600 F and above m a y be encountered b y text i le m a t e r i a l s a t

m e d i u m a l t i tudes a t about Mach 4.

Analyzing the ae rodynamic heat ing c h a r a c t e r i s t i c s of pa rachu te - type t r a i l ing d e c e l e r a t o r s has up to the p r e s e n t t i m e been b a s e d on

m o r e intui t ive p r inc ip les than ac tua l flow da ta . One p r o c e d u r e used

now i s outlined in Refe rence 8 2 . A s h o r t desc r ip t ion of th is p r o c e -

d u r e fol lows. A schemat ic of a typica l t r a i l ing-pa rachu te d e c e l e r a -

t o r i s shown in F i g u r e 38. The t r a i l ing pa rachu te i s a s s u m e d to be

p receded by a bow-type shock a t the in le t f a c e , and constant s t agna-

t ion condi t ions , which a r e funct ions of the f r e e - s t r e a m flow prop-

e r t i e s , a r e a s s u m e d to ex i s t ins ide the canopy. The p r e s s u r e r a t i o

a c r o s s the roof panel a l s o i s a s s u m e d to be g r e a t e r than c r i t i c a l s o

the sonic flow e x i s t s in the many openings of the roof panel . Using

B a r t z ' s equation f o r turbulent flow in a nozz le , the heat t r a n s f e r co -

eff icient in a typical o r i f i ce can be e s t i m a t e d using the following:

D = or i f ice th roa t d i a m e t e r , i t , t

po = v i scos i ty a t to ta l t e m p e r a t u r e , l b / f t - s e c ,

c = spec i f i c h e a t , ~ t u / l b - d e g F , P

P r = P r a n d t l n u m b e r ,

P t = to ta l p r e s s u r e , p s f ,

2 g = gravi ta t ional cons tan t , 3 2 . 2 f t / sec ,

.!I ,I.

c = c h a r a c t e r i s t i c o r i f i ce ve loci ty , f p s ,

r = r a d i u s of roof e l e m e n t , f t , e


S K I R T

R O O F E L E M E N T

@ S K I R T S E C T I O N

R O O F

CROSS-HATCHING SHOWS

E X I T A

E L E M E N

Figure 38 - Parachute Configuration


-1-

A"' = orifice throat a r e a , sq ft .

A = orifice station c ross -sec t iona l a r e a , sq f t , and

IJ = dimensionless factor accounting for density and viscosity variation in boundary l aye r .

The heat t r ans fe r cocfficient and heat flux r a t e s can be estimated to

determine the tempera ture r i s e in duration of the heating. Once the

heat t ransfer coefficients have been est imated, the variation in the

heat flux ra te into the fabric a s a function of deceleration t ime can

be calculated using t ra jectory data for the par t icular application.

In some cases where the decelerator ma te r i a l is of thin g a g e , i t is

sufficient to calculate the tempera ture r i s e ra te using a heat sink

type of heat balance such a s :

where

h = heat t ransfer coefficient, ~ t u / h r -sq ft,

T = adiabatic wall t empera ture , deg F, aw

T = mate r i a l t empera ture , deg F, W

T = t ime,

p = density of ma te r i a l , pcf,

c = specific heat of mater ia l , ~ t u / l b -deg F,

8 = thickness, f t ,

E = emissivity,

o = Stef an-Boltzmann constant, and

6 = heat f lux r a t e , ~ t u / h r - s q ft .

In other ca ses where a generous amount of heating i s applied to the

load car ry ing mater ia l , i t i s neces sa ry to use a t ransient heat con-

duction type of solution.


F o r such a c a s e , the dece l e r a to r m a t e r i a l s usually f o r m a nonhomo-

geneous l aye r that c a n be c l a s s ed a s a poor conductor . I t i s then

appropr ia te to consider the heating of th is type of m a t e r i a l based on

t rans ien t , one-dimensional heat conduction. The par t i a l d i f ferent ia l

equation fo r hea t conduction in a one-dimensional s l ab is 7

where (for Equations 5 through 8 )

7 = t ime , s e c ,

y = depth, f t ,

k = t h e rma l conductivity, Btu/ f t -hr -deg F,

CY = t h e rma l diffusivity, sq f t / h r ,

h = adiabatic wall enthalpy, B tu / l b , \ aw

h = cold wall enthalpy, ~ t u / l b , C W

h = wall enthalpy, Btu/lb, W

w = wall heat flux r a t e , Btu/sq ft pe r s e c , and

qcw = cold wall heat flux r a t e , Btu/sq ft pe r sec .

Additional equations for the outer and inner su r face boundary condi-

tions mus t a l so be s ta ted to augment the solution of equation ( 3 ) . The

outer s u r f a c e boundary equation can he wri t ten a s

At the inner wal l , the su r f ace wil l be a s sumed to be a n adiabatic wall

SECTION I1 - AERODYNAMIC DEPLOYABLE DECELERATORS GER - 12616

These equations w e r e then conver ted to f ini te-difference f o r m and

solved on a digital computer a s a function of the hea t flux r a t e s

evaluated and presen ted previously . The cold wal l aerodynamic

heating r a t e s p resen ted e a r l i e r we re coupled t o the t rans ien t heat

conduction solution by the following relat ionship:

Thus , the d e c r e a s e in the heating r a t e s i s compensated fo r by the

enthalpy ra t io .

7. STRUCTURES

a . Gene ra l -

P r e s e n t - d a y high-speed r ecove ry operat ions a r e general ly quite

s e v e r e in weight and s towage-space r equ i r emen t s and in the hosti le

ae ro thermodynamic environment in which the dece l e r a to r m u s t op-

e r a t e . It i s usually of p r i m a r y i n t e r e s t to des ign the l ightes t decel -

e r a t o r that c a n fulfill the s y s t e m r equ i r emen t s . F r o m this genera l

specif icat ion, i t is n e c e s s a r y to choose a m a t e r i a l that can sus ta in

the aerodynamic load a t the potential t empe ra tu r e level . In t e r m s

of deployment conditions in the flight r eg ime of i n t e r e s t , this type

of c r i t e r i a i s available in the f o r m of the data p resen ted in F igu re 2 .

F o r ins tance , the pa r t i cu la r adiabatic wall - t empe ra tu r e l ines have

been d rawn to c o r r e l a t e with the nominal max imum working t empe ra -

t u r e level of s t a te -o f - the -a r t fabr ic m a t e r i a l s . Thus , a nylon fabr ic I I

usually can opera te up t o about 350 F , a Nomex fabr ic up to about / I

700 F, and me ta l f ab r i c s l ike s t a i n l e s s s t e e l and Rene 41 up to 1200 I

I

F. Ma te r i a l capabi l i t ies c an be extended by using hea t - r e s i s t an t I

I

coating. Coatings and thei r effects a r e d i s cus sed in m o r e deta i l i n I

I t em 8 , below. I


Several different decelerator configurations ( see F igures 39 through

42) have been investigated experimentally; applicable s t ructur a1 de - sign parameters generally have been established. Configurations

fo r which documented s t ruc tura l design data a r e available include

Ballutes, spheres , parachutes, cones, inflated sk i r t s , and tension

shells. Each of these s t ruc tura l types i s discussed in m o r e detail in

I tems b - through f , - below.

b. Ballute and Spheres -

(1) Description

Ballutes i l lustrated in Figure 43 a r e woven-fabric r a m - a i r -

inflated p res su re vesse ls of isotensoid design. The inflated

s t ruc ture i s pr imari ly pear-shaped, except for the large c i r -

cumferential burble fence a t , o r just aft of, the maximum

diameter . Ram a i r en ters through a s e r i e s of symmetr ical ly

located side inlets o r through a single large nose inlet. The

fence i s inflated through numerous smal l ports located around

the decelerator proper and beneath the envelope of the fabric

fence. The inflated height of the fence i s up to 10 percent

Figure 39 - 4-Ft-Diameter Decelerators To Be Flight Tested a t Mach 5

-102-


N O T REPRODUCIBLE

Figure 40 - Coated Metal-Cloth, 5 -Ft-Diameter Ballute


of the max imum inflated d i ame te r of the model . Th i s conical

mode l is a gore const ruct ion, f ab r i c a t ed f r o m base m a t e r i a l s

such a s nylon o r Dacron o r f r o m hea t - r e s i s t an t m a t e r i a l s such

a s Nomex.

Refe rence 27 cons ide r s a fabr ic sphe re a s one l imit ing c a s e ; thus ,

the d i scuss ions below can be applied to that configuration a s indi-

ca ted .

( 2 ) Components

The pr incipal components of the Ballute include the fabr ic cover -

ing, the mer id iona l webs , and the fabr ic coating. The fabr ic

cover ing is a h igh-s t rength m a t e r i a l that f o r m s the envelope of

the s t r u c t u r e . The mer id iona l webs help to suppor t the load by

continuing a round the s t r u c t u r e and pass ing through the apex a t

the back . The webs m a y t e rmina t e on a nose f ix ture a t the f ron t

of the model , o r they m a y extend out to become the suspension

l i ne s . The hea t - r e s i s t an t coating applied to the envelope makes

i t nonporous and helps to provide t h e r m a l protect ion fo r the

s t r u c t u r e .

( 3 ) Weights and Volume

The weight of a Bal lu te , W B , i s the s u m of the weight of its com-

ponents. The re fo r e ,

whe re

W = fabr ic weight , f

W m = mer id i an weight , and

W = coa t ingweigh t . C

I


I FLARE LA Figure 41 - Sketches of Sphere, Parachute, Ballute, and F l a r e


NOT REPRODUCIBLE

Figure 42 - 4-F t -D Parasonic Parachute 0



F i g u r e 4 3 - TB- 1 Ballute Configuration

SECTION I1 - AERODYNAMIC DEPLOYABLE DECELERATORS - GER-12616

The weight then becomes

where

A = su r f ace a r e a of the d e c e l e r a t o r , f

f =: design s t r e s s due to the des ign inflation p r e s s u r e and the dece l e r a to r rad ius ,

D . F . =: to ta l f a b ~ l c des lgn f ac to r , which i s the product of safe ty f a c to r , dynamic loading, s e a m efficiency, t e m p e r a t u r e , e t c . ,

K = envelope fabr ic s t rength- to-weight r a t i o , f

h = number of me r id i ans (webs) ,

L = length of each mer id i an ,

T = mer id i an des ign tension load,

D . F. ' =- to ta l me r id i an des ign f ac to r ,

K - mer id i an s t rength- to-weight r a t i o , and m

C . F. -, unft coating weight {weight /area)

Since the Ballute i s a n isotensold s t r u c t u r e , the d i scuss ion of

Refe rence 27 appl ies and can be used to determine the n e c e s s a r y

va lues . F o r p r e l lm lna ry considerations, the r equ i r ed weight

fo r a s t eady- s t a te ( r a m - a i r inflated9 condition i s approximated by

W, = 4 ~ , i r ~ 3 t 2 h " 2 P t nK' t 4nR (C . F~ 1 K

C I This equation u s e s a safe ty fac to r of two and does not include the

weight of the burble fence o r the r i s e r l ine . The mer id i an length 2 and fabr lc a r e a a r e approximately dnR and 4nR , respec t ive ly .


F o r a 10-percent fence , the fabr ic weight is i nc r ea sed by approxi-

ma t e ly 30 percen t .

F igu re 44 p r e sen t s the r e s u l t s of the above equation fo r va r ious

values of

The following h a s been de te rmined exper imenta l ly .

1. A P = 1 w a s sufficient fo r ful l dece l e r a to r /q inflation.

2 - A P ~ / q = 2 to 4 was obtained i n the superson ic

speed r e g i m e .

Hence, the weight of a p resen t ly designed Ballute i s based on a

A p ~ /q of between two and four . However , subsequent ef for t to

lower the resul t ing in te rna l p r e s s u r e for des ign optimization i s

f eas ib le . One method i s to re loca te the r a m - a i r in le t s to a loca-

tion of lower loca l p r e s s u r e s .

Ballute stowage -volume r equ i r emen t s a r e dependent on i t s weight

and packing densi ty . Typical packing-density va lues range f r o m

20 to 30 psf f o r handpack and 30 t o 40 pcf f o r a p r e s s u r e

pack.

c . Pa r achu t e s -

(1) Descr ip t ion

The bas ic parachute i s a well-known configuration u sed a lmos t

exclus ively in subsonic r e cove ry opera t ions . The tendency

toward a n evolution of superson ic -type d e c e l e r a t o r s r e su l t ed in

the e a r l y considera t ion of pa rachu tes f o r high-speed applicat ions

T o da te , va r ious configurations have been tes ted supersonical ly ,

including s o m e compara t ive ly r ecen t high-speed des igns . Sub-

sonic canopies tes ted superson ica l ly include the hemisf lo , the


WEIGHT (POUNDS)

WEIGHTS BASED ON WB = hPR

Figu re 44 - Ballute Weight v s Radius


s tandard f la t , the conical , and the equiflo. Notable supersonic

canopy designs a r e the hyperflo, the P a r a s o n i c , and the supe r -

sonic guide s u r f a c e .

( 2 ) Components

The bas ic components of a parachute a r e i t s drag-producing

canopy and suspension l i ne s . The f o r m e r can be fu r ther sub-

divided, for m o s t superson ic configurations, into a crown, a

roof , and a s k i r t . E a c h sect ion m a y be e i ther porous or non-

porous , but general ly the c rown and roof a r e porous (e i ther m e s h

o r r ibbon) and the s k i r t i s re la t ively nonporous.

( 3 ) Weights and Volume

P a s t re l i ance on parachute-type r ecove ry ha s resu l ted in the

documentation of var ious methods of weight and volume ana lys i s .

Reference 1 indicates s e v e r a l of these methods including the one

d i scussed below, which i s frequently u sed fo r p r e l im ina ry ca lcu-

la t ions . The pr inciples applied a r e applicable, in theory , a t any

Mach number . The des i r ed max imum loading, Fo, i s determined

f r o m overa l l p rog ram r equ i r emen t s , usual ly a maximum g-load

specification. The equation on page 378 of Reference 1 gives

F o X J X c individual l ine s t reng th =

Z X u X o X e X k '

where F i s maximum opening shock, J i s a safe ty f ac to r , Z i s 0

the number of suspension l ines , c i s a fac to r re la ted to suspen-

sion-l ine confluence angle , u i s a factor fo r s t reng th loss a t

connection points, o i s a fac to r re la ted to s t rength l o s s in ma-

t e r i a l f r o m wa te r and wate r -vapor absorpt ion, e i s a factor r e -

la ted to s t reng th l o s s f r o m ab ra s ion , and k i s a fac to r re la ted to

s t reng th l o s s f r o m fatigue. Once the F axia l des ign load level 0

has been es tabl ished (Fo = opening shock factor t imes C Aq, D the s t reng th of each l ine i s obtained with the above equation.


The s t reng th r equ i r emen t s of the invididual l ines c an be d e t e r -

mined by the judicious se lect ion of these f a c t o r s . In gene ra l , Z

(the min imum number of suspens ion l ines extending f r o m the

canopy) is picked to be numer ica l ly equal to D t 4 ) ; however , 0

m o r e l ines a r e usual ly se lec ted s ince a number divisible by four

should be u sed f o r loadlng at,t achment s ymmet ry .

T o de te rmfne the suspens ion- l i re weight, a m a t e r i a l weight pe r

unit of length corresponding to the s t r eng th r equ i r emen t of the

l ines and the suspension- l ine length muhf be found. In s u p e r -

sonic operat ions , the length of each i ine f r o m the canopy to the

confluence point i s approximately 2D Thus , the length of e ach 0 '

l ine loop ( z / Z ) , accounting for ~ t s continuation on around the

canopy through the apex a t the back , 1s 5D . The weight of the 0

suspens ion l ines then becomes

l ine weight = ( 3 X i5Do) W~ unit length .2)

The s t reng th r equ i r emen t s of the cacopy m a t e r i a l a r e found f r o m

the re la t ive suspension- l ine s t reng th r equ i r emen t s b y uslng the

tables on page 3 76 of Reference 1 . The canopy weight c an then

be e s t ima t ed bv

; (weight surf mater ia! Wsur f unit a r e a

)x (A - A n ) .

whe re is the gecme t ry p o r o s ~ t y (openness ; and A is determined

f r o m te rmina l -ve loc i ty requ i rement s using the equation

whe re W =: D . The parachute weight then becomes

w Z W f

+ WM . sur f


An approximat ion of the parachute weight , which h a s been ob-

tained empi r ica l ly f r o m many t e s t s , i s given by the equation

l ine weight) ( Z ) (5Do) Wf = (un i t length

Tha t i s , the suspens ion l ine weight c o m p r i s e s approximately 40

pe r cen t of the parachute weight . F o r i sotensoid designed p a r a -

chu tes , the methods of Refe rence 81 can be used fo r m o r e a c -

c u r a t e r e s u l t s .

Example weights of these drogue- type parachu tes c an be obtained

f r o m Refe rence 1 . F o r example , on page 89 of Refe rence 1, the

weights of r ibbon drogue parachu tes f r o m two feet to seven f ee t

in d i ame te r that a r e capable of withstanding " q ' s " between 135 to

794 psf (below Mach 2) v a r y f r o m 2 to 20 lb . These r ibbons weigh

between 0. 5 to 1. 0 oz pe r l inear ya rd . It i s impor tan t to note that

these weights a r e based on nylon m a t e r i a l that i s designed to take

the "q" load but not capable of withstanding t empe ra tu r e s above

250 F. Based on this su rvey , t he r e was no documented data found

of h igh-speed (above Mach 2. 5 ) pa rachu tes that w e r e capable of

withstanding 600 F, a s was the c a s e of the coated, nonporous d e -

c e l e r a t o r s .

d . A i r m a t Cone - (1 ) Descr ip t ion

The A i r m a t cones shown in F i g u r e s 45 and 46 a r e composed p r i -

m a r i l y of two cone-shaped l a y e r s of f ab r i c , between which a r e

many thin f ib rous s t r ands cal led d rop t h r eads . When the volume

enclosed by the fabr ic l a y e r s i s p r e s s u r i z e d , the fabr ic i s con-

s t r a i ned by the d rop t h r eads to f o r m the d e s i r e d shape . The cone

th ickness (depth between l a y e r s ) i n c r e a s e s with the dis tance f r o m

the apex; this i s done to mainta in s t r u c t u r a l r ig idi ty while the

d i ame te r i n c r e a s e s .


NOSE

><

F i g u r e 45 - A i r m a t Cone Dimens ions

F i g u r e 46 - 80-Deg A i r m a t Cone (Pre in f la ted)


Since fabr ic i s not effective in compression, the internal p res su re

m u s t be sufficient to ensure only tension loadings. Reference 27

shows that the theoretical internal p res su re must be at least 4. 52

t imes the f r e e - s t r eam dynamic p res su re to obtain tension load-

ings in the fabric . Wind tunnel t e s t s ( see References 27 and 48)

supported this theory. It i s important to note that this configura-

tion requi res pressurizat ion f rom an additional source such a s

an a i r bottle. There i s no documented evidence clear ly showing

r a m - a i r inflation design feasibility, although this type of infla-

tion method would indeed reduce the overal l sys tem weight.

Weight and Volume

An analytical method of predicting the weight of the Airmat cone

i s given in Reference 27. This method i s predicated on the a s -

sumption that the net external p res su re over the face of the cone

i s constant and i s given by P - C q. The internal p res su re must D be sufficient to counter the compressive loading of this external

p res su re . Accounting for both meridional and hoop s t r e s s e s ,

the total cone weight, with an included safety factor of 2, i s given

a s

This does not include the weight of the drop threads, which i s

approximately an additional 30 percent by comparison. A plot

of weight ve r sus radius for var ious values of q i s given in F ig -

u r e 47.

e . Inflated Skirts (F la res ) - At present, inflated sk i r t s that have been built a r e comprised of coated

fabr ic compartments formed by seve ra l right c i rcular cone frustums

with a common theoretical apex a s shown in F igure 41. Each adjacent


D E C E L E R A T O R WEIGHT NOT INCLUDING DROP THREADS (POUNDS)

Figure 4 7 - Airmat Cone Weight vs Radius for Various Values of q

pair of cone f rus t rums intersects along two straight l ines that must

be connected by an internal fabric web to satisfy equilibrium of the

hoop s t r e s s e s a t the inter section. Longitudinal meridian s t r aps a r e

placed along the outside intersection (gore seam) to withstand the

longitudinal reaction forces . In addition to the fabric s t ruc ture , a

metal retaining ring connects the inner and outer surfaces of the

compartments. While no single weight equation has been derived,

procedures shown in Reference 27 can be used to determine weight.

f . Tension Shells -

(1) Description

A tension-shell configuration (see Reference 66) i s shown in

Figure 48. The tension shell o r tension shape i s a concept in

which aerodynamic surface loads a r e ca r r i ed in tension. Since

compression and buckling effects a r e eliminated, the full strength

of the construction mater ia l can be utilized, and dece lera tors of


TENSION S H E L L

R = R A D I A L D I S T A N C E T O P O I N T O F T A N G E N C Y O F N O S E C A P A N D S H E L L

p = P R E S S U R E A C T I N G O N T H E S H E L L

I' = R I N G C R O S S - S E C T I O N A L R A D I U S

t = T H I C K N E S S

P = A N G L E B E T W E E N A X I S A N D T A N G E N C Y S U R F A C E

4 = A N G L E B E T W E E N F L O W A N D N O R M A L

T O S U R F A C E

Figure 48 - Tension Shell Loading System, Assumed


potentially high s t r u c t u r a l eff iciency a r e poss ible . The candi-

date deployable configuration can be e i the r a semir ig id o r in -

f latable s t r u c t u r e .

The tens ion she l l , shown in F igu re 48, i s bas ical ly a cone-

shaped s t r u c t u r e with a blunted nose . The genera ted she l l s u r -

face , however , i s a concave sur face of revolution. T o e l iminate

hoops s t r e s s e s , a c a t ena ry of revolution was chosen fo r analys is

i n Refe rence 65. It i s feas ible that this inflated ba se r ing ( t o ru s )

can be a n inflated s t r uc tu r e .

( 3 ) Weight and Volume

Refe rence 65 p r e sen t s a method for es t imat ing the weight of the

individual components and the total weight of the tension she l l .

This method a s s u m e s a var iable th ickness in the m a t e r i a l , s o

that the membrane s t r e s s i s constant and equal to the allowable

value . C i rcumferen t ia l s t r e s s e s a r e a s sumed to be negligible.

F o r the upper she l l and nose cap , the m a s s i s e s t imated to be

where

1 s e K 2 & [ (K'T)]~-K' [ ji(liT)] , - = - er f (K) - er f - d ( K ) - 4 -% R b

F o r the r ing , a uniformly dis t r ibuted load i s a s sumed . The m a s s

of the r ing is es t imated in Refe rence 66 to be

where


u = allowable s t r e s s , a

p = m a t e r i a l densi ty ,

q = dynamic p r e s s u r e ,

K' = shape p a r a m e t e r assoc ia ted with Newtonian

p r e s s u r e , qRb N '

0

l s = shel l length in mer id iona l d i rec t ion ,

R = rad ius perpendicular t o a x i s ,

Rb = rad ius of model b a s e ,

RT = r ad i a l d is tance to point of tangency of nose cap and tension shel l ,

Nd = mer id iona l s t r e s s resu l t an t , posit ive in tension,

N = N evaluated a t R = 0 d R b '

E = modulus of e las t i c i ty , and

Stowage and deployment of this configuration have not been

documented.

8. MATERIALS

a . Gene ra l -

Mate r i a l information in th is r e p o r t i s l imi ted essen t ia l ly to ( 1 ) woven

f ab r i c s of synthetic f i be r s and m e t a l f i laments and ( 2 ) a va r ie ty of

coating m a t e r i a l s fo r porosi ty reduction and heat protection of woven


f a b r i c s . Dece le ra to r s t r u c t u r e r equ i r emen t s of s m a l l predeployment

volume, low weight , and high s t r eng th indicate that flexible s t r u c t u r e s

a r e the m o s t feas ible Of the f lexible m a t e r i a l s , woven f ab r i c s a r e

the m o s t applicable f o r the ma jo r i t y of +he dece l e r a to r pe r fo rmance

r equ i r emen t s .

In genera l , the evaluation of woven f ab r i c s is m o s t conveniently a c -

complished by the ana lys i s of the bas ic unit of fabr ica t ion - tha t is ,

f i b e r s , y a r n s , o r f i l aments . Th i s i s due to the myr i ad of va r iab les

involved in the d i r ec t a n a l y s ~ s of a woven f ab r i c including those of

the s a m e bas ic units a r l s i n g f r o m the var ious weave pa t t e rn s , f ab r i -

ca t ion techniques , cloth var ia t ions , nonhomogeneity of the cloth, e t c .

Thus , to provide a compara t ive ly e a s y yet re la t ively effective method

of woven cloth evaluation, at tention i s given to the bas ic units f r o m

which the c h a r a c t e r l s t i c s of the f ab r i c m a t e r i a l (woven cloth) a r e

l a rge ly dependent.

In addit ion, exper imenta l data of va r ious types of woven fabr ic (unit

weights and s t r eng th s ) t e s t s over a wide range of loading conditions

(and a t va r ious t e m p e r a t u r e s ) a r e not avai lable , Hence, m a t e r i a l

t e s t da ta desc r ip t ions and discussions that follow a r e l imi ted to the

bas ic f i b e r s , y a r n s , o r f i l a m e r t s .

Impor tan t f ibe r qualities o r cha r ac t e r l s t l c s f o r deployable dece1erato1-

m a t e r i a l s include the following: (1 ) high s t reng th , ( 2 ) t empe ra tu r e r e -

s i s t ance ( 3 ) hlgh modulus of e l a s t l r l ~ y , (41 f lexlbll l ty, (5) ab ra s ion

r e s i s t ance and ( 6 ) chemica l s t a b l l ~ t y . A revlew of these bas ic p roper - t i e s a s r e l a t ed to use in f lexlble s t r u c t u r e s shows that the d e s l r e d high

modulus of e l a s t lc i ty and f1exib;lif c.7 charac te r1 st?: s a r e contradictory

and a r e difficult p rob lems fox tewtile technology and productlon. Cur -

ren t ly available f i be r s w ~ t h gor d t empe ra ru r e -resistance qualities a l s o

tend to have high modulus c h s r a c ~ e r i s t i c s , maklng t empe ra tu r e r e s i s -

tance and flexibility difficult to a t t a m in a single fabr lc .


Table XI11 s u m m a r i z e s the effects of va r ious environmental conditions

on the manmade and na tu r a l text i les that have been used in aerodynamic

d e c e l e r a t o r s . Table XIV gives the modulus of e las t i c i ty and f i lament

s i z e re la t ive to nylon and f ibe rg lass f o r o rgan ic , synthet ic , and m e -

ta l l ic m a t e r i a l s .

b . Text i le Ya rns and F i b e r s - (1) General

T o da te , m o s t dece l e r a to r applicat ions a r e f i l led by woven f ab r i c s

of nylon, Dacron , o r Nomex. Thus , the proponderance of data

avai lable , appropr ia te f o r d e c e l e r a t o r s , a r e assoc ia ted with these

t h r ee ya rn s . In the following d i scuss ion , va r ious p rope r t i e s of

these yarns wi l l be de sc r i bed and the i r u se in t e r m s of environ-

menta l and manmade conditions wil l be analyzed.

As i s the cus tom with a l l engineer ing m a t e r i a l s , f ibe r -breaking

s t reng ths c an be l i s t ed on a ps i b a s i s . More commonly, however ;

the texti le t r a d e u s e s the t e r m " tenaci ty" to de sc r i be s t reng th on a g r a m pe r den ie r (gpd) b a s i s s ince (1 ) a f i b e r ' s o r ya rn ' s weight

pe r length c a n be de te rmined e a s i e r than i t s c r o s s -sect ional a r e a

and s ince (2) ya rn weight is a n impor tan t texti le physical and eco-

nomic fac to r . Since den i e r i s based upon weight p e r unit length,

tenaci ty obviously i s influenced by the speci f ic g rav i ty of the f i be r ,

while s t reng th p e r unit a r e a i s not . Relat ionship between these two

p rope r t i e s i s :

Tens i l e s t reng th (p s i ) = 12, 800 X specif ic g rav i ty X tenaci ty (gpd)

Consequently, s t reng th re la t ionships of the ya rn s wi l l , in the fol-

lowing d i scuss ion , often be m e a s u r e d in t e r m s of tenaci ty . F i b e r

tenaci ty f o r va r ious text i les is l i s t ed in Table X V .

- a Denier is defined a s the weight in g r a m s of 9000 m of ya rn .


Envi ronment Cotton 1 Silk I V l s c a s r Rayon I F o r t ~ s a n I Nylon I Orlun

Age

Sunlight

Chemica l s

Moths

Mlldew

Hlghly res i s t an t to d r y h r a t ; yeilaws a t 248 F , decomposes a t 302 F . b u r n s readily

Loses 5trength: f o r m a - t ~ o n of oxycellulose; tendency to yellowing

D ~ s ~ n t e g r a t e d by hot d i - lu te acids or cold canc. a c ~ d s . Shells ( m e r c e r , . sa t ion) ~n c a u s t i r s damaged by prolonged exposure i n p r e s e n c e of alr. Bleached by hypo- ch lo r i t e s and pe rox ides , oxidtzed ~ n t o oxycellulose by s t rong o x i d ~ z i n g a g e n t s

Not at tacked

Poor r e s ~ S t a n c e un less

Begins to decompose a t 270 F : rapid d l s ~ n t e g r a - tlon abovc 300 F ; b u r n s readily

Slight yellowing and 105s o f t e n s l l r s t r r n e t h

Loses t ens i l e s t r eng th . a f fec ted m o r e than cotton

F a ~ r l y zea l s t an t t o weak a c i d s ; dissolved by s t rong actds excep t " I ~ ~ L c . I"se"s1tl"e t o d ~ l u t e a l k a l ~ un less hot; dissolves >n s t rong a l - k a l ~ s . Above pH1 l and below pH3 s t a b i l ~ t y d e - creases rapidly

Ree i s t an t

Attacked s l ~ g h t l y

Attacked

E n v ~ r o n m e n t I Dacron I G lass F i b e r

C h e m i c a l s

Organ ic so lven t s

Mothe

Mildew

Hlghly res t s t an t to degradation and discolor- a t ion ; melts a t 480 F

Virtually none

Loses etrength on p r o - longed exposure ; no d ~ s - co lo ra t ion

Good res i s t ance t o m i - n e r a l acids excep t conc . su l fu r i c . Good r e s ~ s t a n c e to weak a lka l i , m o d e r a t e to s t rong a lka l i a t r o o m t e m p ; disso lves in hot s t r o n a alkali . Genera l good ;es?etance t o o the r chemica l s ; excellent t o bleaches a n d oxidizing agen t s .

Genera l ly insoluble; soluble in s o m e phenolic compounds

Not at tacked

Good res i s t ance

Will not burn: s t r e n g t h l o s s s t a r t s a t 600 F ,con- t inues to l lmi t tng t emp. of 1000-1500F . softens 1 5 0 0 F

None

None

Good res ia tance t o a l l but hot s t rong ac ids Attacked by hot solu- tiona of weak alkalis and cold ~ o l u t i o n s of s1ror.g a lka l i s . Genera l - ly good res i s t ance .

Insoluble

Not at tacked

Wholly r e s i s t a n t (b inder m a y be a t t acked)

Loses s t reng th above 300 F , decomposes a t 350 F to 400 F, b u r n s readsly

Loses t o n s ~ l e s t r eng th a f t e r prolonged expo- S u r e ; v e r y l l t t le d i s - coloration

St rong a lka l i causes swell tng and reduces s t r eng th . Attached by s t r o n g o%dlz>ng agents: not d a m a g e d b y hypo- ch lo r i t e or p e r o x ~ d e b leaches

Genera l ly insoluble; so lub le I" cupram- monium

Scorches ~n ircrnng a t about 20 C h i g h r than ro t ton , otherwise l tke cotton, viscose rayon

Little or none

Lases s t reng th t ends to co lo r

D ~ s i n t e g r a t e s in hot d i - lute or cold co lcen t ra led a r ~ d s . S t rong caus t sc s h r ~ n k s , as ~ n m e r c e r i z . Ing R e n s t a n t to b leaches , phernla, and dyehouse reagen t s

Unaffected

Yellow s l ~ c h t l y a t 300 F when exposed fo r 5 h r ; me:ts a t 482 F

Vl r tua l l ) none

Loses s t r e n g t h on p r o - longed e x p o s u r e ; n o d l s - c o l o r a t ~ o n ; b r lgh t y a r n m o r e resistant than semi-dull

Boil ing ~n 5 % HCI u l t i - ma te ly causes d i s ~ n t e - grat ,on: dissolves in co ld conc su l fu r , c or n i t r l c a c t d s . Subs tan- t t a l ly i n e r t to a l k a l ~ . Genera l ly good r e s i s - t ance to o the r c h e ~ i c a l s

Insoluble excep t in s o m e phenollc compounds and conc f o r m i c a c i d

S t K k s a t 455 $: s h g h t l o s s ~n s t reng th a i t e r 32 days I" r:r a t 275 F n ie l t s a t 480 F

V ~ r t u a l l y none

V e r y r e s i s t a n t to de- g r a d a t ~ o n by u l t r av io le t Ltght and a t m o s p h e r e

Good t o exce l l en t re- s ~ s t a n c e t o m ~ n e r a l acxds Faxr to good re- szs tance to weak alkalis Not h a r m e d by o i l s . g r e a s e s , n e u t r a l s a l t s and s a m e ac id s a l t s

Unaffected by c o m m o n so lven t s

Not at tacked 1 Not at tacked 1 Not a t t acked I Not a t t acked

Attacked

Vtrtually none under Virtually none I Vir tua l ly none n o r m a l condit ions 1

5% shr inkage a t 165 F ; so f t ens a t 225 to 235 F. m e l t s a t 230 to 250 F ; s low burnxng

Pro longed exposure de - M o d t r a t e resistance Loses s t r e n g t h on p r o - creases t e n s ~ l e s t r eng th

I longed e x p o s u r e , s u r f a c e t u r n s b ronze

Polvethvlene 1 Mvlar I Nomex H T - I I

S a m e ae f o r co!ton

m e l t s 482 F h a s 60 % room temp. s t r u c t u r a l s t r e n g t h

V e r y r e s i s t a n t to a c l d s . Genera l ly good r e s i s t - a n c e t o c a u s t i c s and o the r chemica l s

Ineoluble, but swe l l s in ch lo r ina ted hydrocarbon8 a r o m a t i c s

Good r e s l s t n n c e

I Not a t t acked

Good r e s i s t a n c e (coa t - l n ~ m a y b e at tacked1

1 Goad r e s i s t a n c e

t o common c h e ' n i c a l s

Not at tacked

Good r e s i s t a n c

Acid r e s t s t a n c e be t t e r than nylon 6-6; not as good a s Dacron o r Or lon ; degraded by s t r o n g a lka l i a t e l eva ted t e m p e r a t u r e

Highly r e s i e t a n t t o m o s t hydrocarbons

Not at tacked

Good r e s i s t a n c e

S o u r c e - Reference I . I


TABLE XIV - FILAMENT DIAMETERS REQUIRED FOR FLEXIBILITY

Mater ia l

Nylon

Silk

Carbon

Viscose rayon

F ibe r f r ax

F i b e r glas s

F u s e d s i l i ca

Gold

Columbium

Plat inum

I ron , nickel , copper

Aluminum oxide

Tungsten, molybdenum

I r id ium

-4, ,I-

Source - Reference 86.

Modulus of e l a s t ici ty

(p s i x

Diameter requ i red for s a m e flexibility

19 u nylon 15 u f iberg lass

Preceding page blank -125 -


TABLE XV - FIBER TENACITIES"

I. D r v tenaci tv 1

Mate r i a l

G r a m s Per

denier (gpd)

Pounds p e r squa re inch , (ps i )

I Wet tenaci ty

I P e r c e n t of d r y tenaci ty

Asbes tos

Cotton, r a w

Cotton, m e r c e r i z e d t

Flax

Hemp

Henequen

Ju te

Manila abaca

Ramie

Silk

S i sa l

W 001

Ac r i l an ac ry l i c

C r e s l a n ac ry l i c

Or lon ac r ylic

Zef ran ac ry l i c

Aceta te

A r n e l t r i a ce t a t e

A r n e l 60 t r i a ce t a t e

Teflon f luorocarbon

Glass

Dyne1 modac r ylic

V e r e l modacry l ic

:;: Source - Reference 88.

+ c o m p a r e d with a n unmerce r i z ed cotton control value of 2 . 8 gpd. - 126-

S E C T I O N I1 - AERODYNAMIC D E P L O Y A B L E D E C E L E R A T O R S G E R - 12616

T A B L E XV - F I B E R T E N A C I T I E S " ( C O ~ ~ ~ ~ ~ ~ ~ )

I D r y t e n a c i t y

M a t e r i a l

Nylon 6 , r e g u l a r

Nylon 6 , h i g h t e n a c i t y

Nylon 66 , r e g u l a r

Nylon 66 , h igh t e n a c i t y

Wet t e n a c i t y G r a m s

P e r d e n i e r

D a r v a n n y t r i l

P o u n d s p e r

P o l y e t h y l e n e , low d e n s i t y

P o l y e t h y l e n e , h igh d e n s i t y

P o l y p r o p y l e n e

Po lyv iny l a l c o h o l

s q u a r e i n c h ( p s i )

D a c r o n p o l y e s t e r , r e g u l a r

P e r c e n t of d r y t e n a c i t y

D a c r o n p o l y e s t e r , h i g h t e n a c i t y

F o r t r e l p o l y e s t e r

Kode l p o l y e s t e r

V y c r o n p o l y e s t e r

S a r a n

L y c r a s p a n d e x

V y r e n e s p a n d e x

S t e e l

Vinyon

V i s c o s e r a y o n , r e g u l a r

::: S o u r c e - R e f e r e n c e 88.

-127-

SECTION I1 - AERODYNAMIC DEPLOYABLE DECELERATDRS GER- 12616

TABLEXV - FIBER ~ ~ ~ ~ ~ ~ ~ ~ ~ ' ~ ( c o n t i n u e d )

I D r y tenacity

Wet tenacity L

Mate r i a l

G r a m s Per

Viscose rayon, i n t e r - mediate tenacity

Pounds p e r den ie r ( g ~ d )

Viscose rayon, high tenaci ty

C u p r a m m o n i u m r a y o n

X L (Avron) rayon 1 4. 1 1 8 0 , 0 0 0 1 7 3 . 1

2 . 4 to 3 . 2

F o r t i s a n saponified ace ta te

F i b e r 40 (Avri l ) rayon

Corva l rayon 1 2. 0 to 2. 2 1 37 , 000 to 43 , 000 1 59. 1 to 60. 0

squa re inch (ps i )

3 . 0 to 5 . 0

1. 7 to 2 . 3

Zan t re l rayon 1 3 . 8 to 4. 0 1 73, 500 to 7 7 , 000 1 74. 0 to 75. 0

P e r c e n t of d r y tenacity

45 , 000 to 6 2 , 000

6. 0 to 7. 0

5 . 0

.*A -a.

Source - Reference 88.

50 . 0 to 59 . 3

5 6 , 0 0 0 to 9 7 , 0 0 0

3 3 , 0 0 0 to 4 5 , 0 0 0

63 . 3 to 72. 0

53 . 0 to 61. 0

117, 000 to 1 3 6 , 0 0 0

9 6 , 0 0 0

85 . 0

70. 0


( 2 ) Effects of St,erilization and 'Vacuum

The s t a t e of the a r t re la t ing to the effects of biological s t e r i l i -

zat ion and vacuum soaking on si lk, nylon, D a c ~ o n , and Nomex

m a t e r i a l i s adequately descr ibed i n Reference 87, Major con-

clusions of the re fe rence a r e disc.ussed below.

Silk was immediate ly el iminated, and nylon was s o se r ious ly

degraded by t h e ~ m a l s te r i l i za t ion that fu r ther test ing was not

considered. If the t he rma l s te r i l i za t ion could be mitigated,

nylon probably would withstand the chemica l s te r i l i za t ion with-

out s e r i ous degrddation. Du Pont r epo r t s that nylon has been

subjected to ethylene oxide and to F r e o n 12 , separa te ly , a t t em-

pe ra tu r e s higher than the 104 F called fo r in Reference 86 wi th-

out s e r i ous degradation. There fore , the combination probably

would not be s e r i ous ly harmful . The nylon, a f t e r t he rma l c y -

cling, was marked ly s t i f fe r and l e s s f lexible. No adhesion of

the nylon to i tself o r to the s ta in less s t e e l p la tes was observed

(in con t ras t to the p re l iminary t e s t s where adhesion of unscoured

m a t e r i a l s was observed) . No adhesion was observed with e i ther

Dacron o r Nomex. Thus, long- t ime, packed s to rage a t elevated

t empe ra tu r e with o r without vacuum should not be a s e r i ous con-

c e r n fo r fabr ic s t r u c t u r e s of nylon, Dacron, o r Nomex. Dacron

i s a promising candidate m a t e r i a l fo r a s te r i l i zab le re ta rda t ion

sys t em. Average s t reng th 10s s e s of all dacron m a t e r i a l configd-

ra t ions resul t ing f r o m both s ter i l iza t ion and vacuum exposures

did not exceed 20 percen t . Nomex i s a l so a promLsing candidate

m a t e r i a l fo r the M a r s en t ry re ta rda t ion sy s t em. Average

s t reng th l o s se s of a l l Nomex m a t e r i a l c o n f i g u r s t i o ~ s ~ e s u l t i n g

f r o m both s ter i l iza t ion and s7acuum exposures dld not exceed

5 percen t .

Depending on the specific m a t e r i a l and the t empera ture -vacuum

envelope, some stiffening and heat set t ing of folds and wrinkles


could occur with possible adverse effects on deployment. Negli-

gible effects due to folding and compacting were observed.

(3 ) Effects of Temperature and Sustained Loadings

Figures 49 and 50 present typical strength relationships for ny-

lon, Dacron, and Nomex under various conditions. These curves

indicate that optimum strength-to-weight character is t ics for un-

degraded mater ia l s a t room tempera ture a r e obtained with nylon,

Dacron, and Nomex, respectively. Figure 50, however, indi-

cates that these yarns appear in the same order when listed by

their sensitivity to initial elevated temperature values and sus-

tained loads applied a t room temperature. Thus, af ter exposure

to a preload temperature of 350 F , for example, Dacron i s su-

per ior to scoured nylon af ter a loading time of 5 h r and Nomex

i s superior to Dacron af ter a loading t ime of 100 h r . These ef-

fects become m o r e pronounced with exposure to higher preload

temperatures , with Dacron having almost twice the tenacity of

scoured nylon af ter exposure to 425 F and a relatively short 1-

h r loading. Nomex, on the other hand, remains usable a f te r

exposure to preload temperatures up to 580 F and a continuous

loading time of 200 h r .

Figure 51 indicates the relative performance of nylon, Dacron,

and Nomex when subjected to a sustained load a t an eleva.ted

temperature. At a temperature of about 400 F, nylon, Dacron,

and Nomex, respectively, exhibit the best initial propert ies .

Above 400 F, Nomex i s the only one of the three that will with-

stand a sustained load.

Somewhat l e s s temperature sensitivity was observed with un-

scoured nylon a s opposed to scoured nylon, which resulted -

apparently - f rom the protection of the manufacturing oils. No

difference between scoured and unscoured D a c ~ o n i s indicated

in Reference 86.


9 I

N Y L O N

D A C R O N

8 -

7

6

5 -

4 . / #

/-/

/ 0 3

NOMEX (500 F)

/.Z+--

/ //--

- 4-

2 //--

W z I W

I 0 -. Y a u CI 1 - > t 0 4 z W I-

0 2 4 6 8 10 12 14

E L O N G A T I O N ( P E R C E N T )

R E F - E I D U P O N T B R O C H U R E S NP-33 ( O C T O B E R 1963) A N D X-188 ( A P R I L 1964)

Figure 49 - Typical S t r e s s -S t ra in Curves for Dacron, Nylon, and Nomex

-131-

P ' m I+, c-t

:; - 3

I I I SCOURED NYLON 6-6

EXPOSURE (HOURS) REF - E. I. DU PONT BROCHURES NP-33 (OCTOBER 1963) AND X-188 (APRIL 1964)

i


8

7

6

F W z W 0 \

!2 2 (3 - > k U a z W

(3

Z_ Y a W IL

2

- 100 0 100 200 300 400 500 600

DEGREES ( F A H R E N H E I T )

R E F - E . I D U P O N T BROCHURES NP-33 (OCTOBER 1963) AND X-188 ( A P R I L 1964)

F i g u r e 51 - Break ing Tenac i ty a t Var ious T e m p e r a t u r e s

SECTION I1 - AER0DY'NAM:IC DEPLO'YAB LE DECELER.ATORS G E R - 1261 6 --

(4) Stiffness

At r o o m t e m p e r a t u r e s , nylon is m o r e f lexible than Dacron, and

both a r e m o r e f l e x i b l e than Nornex fo r elongations below approxi-

ma t e ly 6 perc,e.c;t ( s e e 1"igrire 49). W h e n s t ~ e s s e d to b reak , how-

eve r , Norrlex is the rrmsf. flexible, with Dac-ron and nylon both

being approximately 50 pe rcen t st , ffer .

(5) Shrinkage

The hea t sh r inkage of v i rg in f j b e r is p resen ted in Figzlre 52.

Dacron r eaches about 25 percen t sh r inkage a t about 440 F; nylon

reaches 16 pe r cen t a t the s a m e terr lperature and Nornex only

4- 1/2 pe rcen t at 600 F. T h e s e shr inkages occur i n about 30

s e c f r o m the t ime the y a r n r eaches t empe ra tu r e . While nylon

wil l s t d r t shr inking frorrl t empe ra tu r e s above 75 F, Dacron does

not s t a r t unti l t empe rd tu r e s above 140 F a r e obtained. The

c r o s s o v e r is at 4 pe rcen t shr inkage a t 225 F. A heat -se t t ing

p r o c e s s obvio.usly m u s t be cal led out i n the p rocu remen t of n y -

lon and Dacron before pa t t e rns a r e cut,.

(6) Radiation Res i s tance

Nylon, Dacron, and Nomex a r e a l l degraded in t ens i l e s t r eng th

and elongation by i r r ad i a t i on with ul t raviole t . The i r r e sponse s ,

max imum and min imum, a r e not n e c e s s a r i l y to the s a m e w-ave-

lerlgths ( s e e F i g u r e s 53 through 55). Nylon is l e a s t affected by

369 mxi and m o s t degraded b y 244 mp; Dacron l e a s t by 369 rm

and m o s t by 314 rrgl; Nornex l e a s t by 314 mp and m o s t by 369 mp.

Norrlex h a s the b e s t long--rar,ge r e s i s t ance s , B a r g raphs ( s e e

F igu re 56) shorn how ul t raviole t radla t ion and elevated t e m p e r a -

t u r e s af fect Nomex.

Gamma radia t ion r e su l t s a r e p r e sen t ed fo r Nomex i n Flg.\xre 57.

Radiat ion r e s i s t ance of Nornex, Dacron, and nylon 6-6 i s p r e -

sen ted in Table XVI with r e spec t to v a r i o ~ ~ s radia t ion sou rce s .


F igure 53 - Variation of Tensi le Strength and Elongation of Nylon Fibers I r rad ia ted i n Nitrogen a t 244 mp, 314 mp, and 369 9

0

W a o \\ Z 3 0 a 40 .

m

- I t- 13 z ,. 20 + U)

w z! m Z W t- 0

0,

X- 314 m p

A- 244 m p - 0 - 369 m p

5 W U K W a - Z 'O 0 F 4 13 Z 0 A W

0 500 1000 1500 2000 2500 l NCIDENT ENERGY (JOULES/SQ CM)

? A

L

SOURCE-RE F 89


0 500 1000 1500 2000 2500 3000

INCIDENT ENERGY (JOULES/SQ CM)

F i g u r e 54 - Var ia t ion of T e n s i l e P r o p e r t i e s wi th Incident E n e r g y f o r D a c r o n I r r a d i a t e d i n Ni t rogen with A-H6 L a m p

SECTION I1 - AERODYNAMIC D E P L O Y A B L E D E C E L E R A T O R S G E R - 126 16 ------

F i g u r e 55 - V a r i a t i o n of T e n s i l e S t r e n g t h a n d U l t i m a t e Elongat ion of Nomex I r r a d i a t e d i n N i t rogen wi th U l t r a v i o l e t L i g h t a n d with Vi s ib l e Light (437 mp)

- I U = 1.00 - W K 4 3

SI 0.75

a 0 z 3 0 a

0 50 0 - I I- C7 Z W K + 0 25 In W 2 Ln z W I-

0 -

30

437 m p

- 20 I- Z W U K W a - Z 10 s! I- u 0 Z 0 A W

0 500 1000 1500 2000 2500 3000

SOURCE-REF

INCIDENT ENERGY (JOULES/SQ CM)

89

( V I S I B L E )

3500

369 m p 0

4000

SECTION I1 - AERODYNAMIC D E P L O Y A B L E D E C E L E R A T O R S G E R - 12616 --

6.0 ( A )

8 HR

U L T R A V I O L E T

5.0 CONTROL

[L U L T R A V I O L E T

f T E M P E R A T U R E 3.0 AGED BROKEN A T

n \

ROOM T E M P E R A T U R E ln E


u f T E M P E R A T U R E

AGED BROKEN

W A T T E M P E R A T U R E I-

6.0 ( B)

50 HR


CONTROL

U L T R A V I O L E T + T E M P E R A T U R E

f 3.0 AGED BROKEN A T

W ROOM TEMPERATURE

U L T R A V I O L E T f T E M P E R A T U R E

U AGED BROKEN a A T TEMPERATURE z W I-

1400 F I 1 500 F 1 1 560 I SOURCE-RE F 87

F i g u r e 56 - D e g r a d a t i o n o f Nomex a f t e r E x p o s u r e to U l t r a v i o l e t Rad ia t ion a n d E l e v a t e d T e m p e r a t u r e s


ORlG l N A L T E N A C I T Y I O V E N A G E D 8 HOURS - E V A L U A T E D A T ROOM T E M P E R A T U R E

E V A L U A T E D A T E L E V A T E D T E M P E R A T U R E I

0 SIMULTANEOUS EXPOSURE T O 400 F AND GAMMA R A D I A T I O N 7 - 1 - 1

F L U X - 3.5 x 10 ERGS GRAM CARBON HR ....- .... .... GAMMA F L U X EXPOSURE a 8 - 1 *-.*....-. A T ROOM T E M P E R A T U R E T O T A L DOSAGE - 3.5 x 10 ERGS GRAM

i I I A L

1 .O 2.0 3.0 4.0 5.0 6.0

TENACITY IN GRAMS/ DENIER

ORIG INAL T E N A C I T Y

E V A L U A T E D A T E L E V A T E D T E M P E R A T U R E

SIMULTANEOUS EXPOSURE T O 7 -1 -1

600 F AND GAMMA R A D I A T I O N F L U X - 3.5 x 10 ERGS GRAM CARBON HR -1

I T O T A L DOSAGE - 3.5 X 10' ERGS GRAM

GAMMA F L U X EXPOSURE A T ROOM T E M P E R A T U R E

1 I I I I I I 1 .O 2.0 3.0 4.0 5.0 6.0

TENACITY IN GRAMS/DENIER

Figure 57 - Effects of Gamma Radiat ion on Nomex a t 400 F (Top) and a t 600 F (Bottom)


T A B L E XVI - RADIATION RESISTANCE: E F F E C T O F

/ Tenacity re ta ined (percen t )

200 mega r e p s

600 mega r e p s 1 76 1 29 1 0 X - r a y s (50 kv)

50 h r

100 h r

250 h r

Brookhaven pile (50 C)

200 mega r e p s

1000 mega r e p s

2000 mega r e p s

32

rumbled

rumbled

-4.

Source - Reference 8 7 .

( 7 ) Weathering

The effects of outdoor exposure on a candidate dece l e r a to r ma -

t e r i a l is a n impor tan t considera t ion fo r determining both p r e -

operat ive and postoperat ive requ i rements . P r i o r t o operat ions ,

f o r example , exposure effects m a y indicate the sensi t iv i ty of the

fabr ic to va r ious types of stowage and handling. Th is , in t u rn ,

d ic ta tes the type and durat ion of the p reopera t ive environment

and indicates the gene ra l acceptabi l i ty of f ab r i c fo r vari.o.us a p -

pl icat ions. In addition, the abi l i ty of dece l e r a to r m a t e r i a l s to

withstand the outdoor environment following operat ions may be

c r i t i c a l i n the s u c c e s s of the mis3io.n. F o r example , degrada-

tion of the f ab r i c due to weather ing m a y ble c r i t i c a l i f , following

a t e s t , the dece l e r a to r i s not immedia te ly located.


Figure 58 indicates the relative resis tance of nylon and Nomex

fabrics to a weathering environment. No generally c lear superi-

or i ty to weathering i s exhibited by either, with nylon 330 being

the least affected and nylon 300 being the most affected.

(8) Yarn- to- Fabr ic Strength Correlation

No simple and universal ratio exists between ya rn and fabric

mater ia l strengths and/or elongations. Fabr ic strength will

invariably be less than the sum of i t s yarns , and fabric elonga-

tion will be g rea te r . Many factors a r e involved including thread

count in warp and fill; basic elongation character is t ics of ma-

te r ia l ; tension maintained during weaving (always g rea te r in warp

than in fi l l) ; ra te of loading; uniaxial o r biaxial s t ress ing; yarn

twist; and type of weave (basket, plain, flat duck, dr i l l , twill,

satin, herringbone, ripstop, and others) . Obvious weaving

considerations a r e the mechanical effect of warp and f i l l threads

on each other and the zig-zag geometry pattern mutually en-

forced, contrasted with an individually tested filament that

would naturally be straight.

c . Filament Materials - Fabrics of woven meta l s t rands show promise for future application.

Fabr ics of stainless s tee l and superalloy meta ls a r e obtainable (at

considerable expense) and have temperature resis tance and strength

character is t ics that a r e suitable for use in temperature environments

up to 1800 F , provided that oxidation-prevention and thermal-insulat-

ing coatings a r e used. Figures 59 through 62 present strength data

for various superalloy meta l wires . To obtain comparative and

meaningful data, the tes ts were performed under the same labora-

tory conditions. Test resul ts ( see Figures 60 and 62), for example,

were conducted a t a crosshead speed ( ra te of specimen elongation)

of 2 . 0 in. per minute. Each specimen was exposed for one minute

to the indicated pre tes t temperature level to ensure that the proper

SECTION I1 - AERODYNAMIC DEPLOYABLE DECELERATORS G E R - 126 16 - - -- - -

X MIL-C-7020, T Y P E I , NYLON 300

EXPOSED (WEEKS) SOURCE-REF 89

EXPOSURE (HOURS)

F i g u r e 58 - C o m p a r i s o n s of Nylon a n d Nomex a f t e r Outdoor E x p o s u r e (Top) a n d a f t e r A c c e l e r a t e d Weather ing (Bot tom)


0 200 40 0 600 803 1000 1200 1400 1600 1800 2000

TEMPERATURE (FAHRENHEIT) SOURCE-REF 90

Figure 59 - High-Temperature Tensile Strength of I . 0-Mil Superalloy Wires

SECTION I1 - AERODYNAMIC - DEPLOYABLE DECELERATORS PA---- GER- 12616

1500 F

1800 F

2000 F

0 1 2 3 4 5 6 7 8 9 10

E X P O S U R E T I M E B E F O R E S T R E S S IS A P P L I E D ( M I N U T E S ) S O U R C E - R E F 90

Figure 60 - High-Temperature Tensile Strength of 0 . 5- and 1 . 0-Mil Wires a s a Function of Exposure Time

SECTION I1 - AERODYNAMIC DEPLOYABLE DECELERATORS GER-12616 -- -

Figure 61 - High- Tempera tu r e Tensi le Strength of 0. 5-Mil Superalloy Wires

- 146-

L i \ \ \ \

\ \ . I 220 ELGl L O Y

200

180 - 0 0 0 x 160 e. I 0 Z - w 140 11: 4: 3

5: 120 11: W a in 0 100 z 3 0 a - I 8 0 F (3 Z W 11: 60 b in

W 2 in 40 Z W F W ; 20

2 I-

I _I 3

0 200 400 600 800 1000 1200 1400 1600 1800 2000


L \ \ *

\ \

i: t 1

\

\

\ KARMA

\, \

300

280

260

240

-

.

.

NICHROME

b

\

I\, V

SECTION I1 - AERODYNAMIC D E P L O Y A B L E DECELERATORS G E R - 12616 -- _ _ _ _ _ _ - - -- -


value had been obtained. Wires of re f rac tory meta l s (tungsten,

molybdenum, tantalum) have the tempera ture- res i s tance charac te r -

i s t i cs needed for t empera ture environments in the upper ranges if

(1) rapid oxidation of the meta l s a t high tempera tures and (2) pro-

ducing and weaving fine fi laments a r e overcome. F igure 63 shows

a strength-to-weight ra t io comparison of re f rac tory and superalloy

me ta l wi res .

Available f iberglass ya rns a s a m a t e r i a l for woven fabr ics have

ser ious deficiencies in flexibility and abras ion res i s tance . However,

the high strength, modulus of elastici ty, and tempera ture- res is tance

charac te r i s t ics of f iberglass make i t a potential ma te r i a l for u se in

a temperature-environment range of 600 to 1000 F , i f the flexibility

and interfi lament abras ion deficiencies can be overcome in the de-

velopment of new f ibers .

Other ma te r i a l s with good potential a s f ibers o r f i laments for wovefi

fabr ics a r e boron f i laments and carbon or graphite f i laments. Since

these ma te r i a l s a r e in the r e s e a r c h and development phases , no spe-

cific data a r e available. P re l imina ry information on boron fi laments

shows a high modulus- to- density ra t io , good tempera ture- res i s tance

charac te r i s t ics , and good s t rength charac te r i s t ics . Carbon and

graphite cloths have good tempera ture res i s tance but need improve-

ment in strength-to-weight ra t io and abras ion res i s tance . Figure 64

shows the strength- retention charac te r i s t ics of graphite, carbon, and

par t ia l ly carbonized ma te r i a l s a t lower tempera tures .

d. Woven Fabr ic Mater ia ls -

(1) Genera l

Available woven fabr ic ma te r i a l s that have been o r a r e applic-

able for deployable dece le ra tor construction a r e l is ted below in

o rde r of increasing s t rength and tempera ture res i s tance :

1. Nylon

STRENGTH-TO-WE IGHT RAT IO

DENSITY I N POUNDS PER SQUARE INCH A

No 8 0

0 0

0 0 0

-I m I T1 m a 9 -I C a m - 8 7 0 9 I ;[I m z I m - -I -

CO 0 0

d

m 0 0

N

8 0

UI 0 C a 0 ? a m 7 (D N O

0

I

100 3 50 600 8 50 TEMPERATURE (FAHRENHEIT) SOURCE-REF 91


2 . Dacron

3 . Nomex

4. F ibe rg l a s s

1 5. Superalloys (Rene 41, Elgiloy, Inconel 702)

Most p resen t applications a r e filled by woven fabr ics of nylon,

Dacron, o r Nomex with o r without coatings. P l a s t i c f i lm i s

suitable only fo r low- load, low- t empe ra tu r e applications. Al-

though f iberg lass has high bas ic s t rength , modulus , and tem-

pe ra tu r e r e s i s t ance , i t i s notoriously vulnerable to folding dam-

age and interf i lament abras ion . F ibe rg l a s s ha s been used v e r y

successful ly in r igid applications but ha s been disappointing i n

flexible- fabr ic applications.

Fab r i c s of woven superal loy me ta l f i laments and r e f r ac to ry

me ta l f i laments show much p romise fo r future application but

a r e a t p r e sen t in the ea r ly s tages of development and a r e ex-

t r eme ly expensive. The m a j o r expense involved i s due to the

high cos t of drawing the m e t a l w i r e down to the p roper f i lament

s ize . Evaluation costs a l s o may be high because they cannot h e

d i rec t ly re la ted among themse lves ( s e e I t ems 1 through 5,

above). However, when woven into cloth, each type will s t i l l

have qualitative per formance re la t ive to each o ther , a s do the

f i laments .

(2) Operational Tempera tu r e Ranges

Potent ia l dece l e r a to r m a t e r i a l s a r e available fo r operation f r o m

300 to 1500 F ( s e e F igure 65). The subs t r a t e m a t e r i a l r e com-

mended f r o m 300 to 600 F i s Nomex (Du Pon t ' s h igh- temperature

polyamide) coupled with si l icone o r f luoroe las tomers . Between /

1000 to 1500 F, subs t r a t e s of s ta in less s t e e l o r Rene 41 woven

cloth coated with a h igh- tempera ture coating, such a s CS- 105

(Goodyear Ae rospace ) , can be used.

k! Y CD [I]

(D 3 e

'?I 2 (D Y [I]

,

100

80

60 - - + Z W 0 IY W

a 40 Z

9 t- Z SU PERALLOYS W k W NYLON K 2 0 . I k C7 Z "EM GLASS W K t- V)

0 500 1000 1500 2000


I


In other operat ional t empe ra tu r e ranges , proved m a t e r i a l s a r e

not now available. One of the m o s t obvious a r e a s fo r develop-

men t of sui table materia1.s l i e s between 600 to 1000 F. At tem-.

pe r a tu r e s above 600 F, the s t reng th of Nomex drops rapidly;

below 1000 F, the penalty i n s t ~ e n g t h - to-weight rat:io paid in the

u s e of s t a in l e s s - s t ee l cloth i s too s e v e r e .

A potential m a t e r i a l to fill th is void i s f ibe rg lass ( s e e F igu re

65) , However, because of i t s se l f -des t ruc t ive na ture under

flexing of pulsating loads , f ibe rg lass does not lend i tself to this

application. Effor ts have been underway for s o m e t ime to mini-

m ize the ab ra s ive na ture of f ibe rg lass , with modera te succes s .

One approach to this p rob lem has been to impregnate the ya rns

with e l a s t o m e r s to prevent adjacent f i l aments i n the y a r n f r o m

rubbing one another . Another approach has been the development

of Beta g l a s s f ibe r by Owens-Corning. The Beta f iber i s a n ex-

t r eme ly fine f i lament . Both of these methods have resu l ted in

some improvement i n the per formance of f ibe rg lass i n flexible

applications; however, this work m u s t be continued to rea l ize

the full potential of f ibe rg lass .

Another possibil i ty of filling the subs t r a t e -ma te r i a l void f r o m

600 to 1000 F i s to extend the capabil i ty of Nomex. Obviously,

the m o s t p rac t ica l way to extend the capability of Nomex i s to

protect the subs t r a t e so i t s t empe ra tu r e never exceeds 600 F.

One way to do this i s to coat the subs t r a t e with ablat ive ma te r i a l ;

the thickness requ i red and the assoc ia ted r igidity of t he rma l in-.

su la to rs a s they a r e now known make the i r u s e prohibiti-ve.

Relatively speaking, the development of low- t empe ra tu r e abla-

t o r s has lagged the development of h igh- tempera ture ab la to rs

considerably. To obtain ablat.ive m a t e r i a l s that wil l sa t i s fy the

requ i rements fo r u s e on decelera.t.ors i s a definite p rob lem a r e a

that w a r r a n t s considerable r e s e a r c h and development.


/ Superalloy meta l fabrics such a s woven stainless s tee l and Rene

41 cloths provide substrate mater ia l capability to 1800 F. Gootl- /

year Aerospace was instrumental in the f i r s t weaving of Rene 41

wire into a cloth having an end count of 200 X 200 and in weaving

seven- s t rand 0. 0016-in. ~ e n k 41 wire into a cloth having a cou-lt

of 100 X 100. However, there i s room for improvement in /

woven metal cloths of stainless s tee l and Rene 41. Higher-

strength, m o r e flexible cloths a r e needed. Higher strength can

be achieved by tighter packing of the meta l filaments during the

weaving operation, and increased flexibility can be obtained by

using smal le r diameter filaments. The feasibility of fabricating

such cloths with textile stranding and weaving equipment has been

demonstrated (see Reference 27). The resulting prototype cloths

were highly flexible, high- strength cloths having a "hand" com-

parable to a textile. These cloths were woven on a prototype

basis . Additional effort will be required to establish productio:?

methods and to improve the fabrics fur ther .

e. Fabr ic Coatings - Coatings a r e applied for one o r both of two pr imary reasons: (1)

reduction of fabric porosity and ( 2 ) protection of the basic fabric

f rom high temperatures of aerodynamic heating o r other heat load.

No rigid line of demarcation exists between coatings that a r e solely

for gas tightness and those that a r e for heat protection. The urethane

and silicone rubbers have higher temperature resis tance than neo-

prenes; however, any coating with a low thermal conductivity can

render a limited heat protection. The formation of an insulating

char i s sometimes a usable mechanism. F o r t ransients , an alumi-

num metalizing can be adequate, but when temperature requirements

a r e high and of fair ly long duration, coating performance can become

quite sophisticated. Heat protection can be afforded by combining

mechanical and chemical reactions to the temperature through char

formation, sublimation, and ablation.


Coating ma te r i a l s a r e available that pe r fo rm sat isfactor i ly up to

1500 F. Up to 600 F, f luoroelastomers pe r fo rm quite well fo r sho r t

periods of t ime. Up to 1000 F, si l icones a r e available. Beyond this

point and up to 1500 F, CS.- 105, high- tempera ture flexible coating i s

recommended. This coating consis ts of a si l icone binder with a glass

f r i t f i l ler and has been used up to 1500 F.

The CS- 105 coating ac t s and feels l ike a sil icone e las tomer a t room

tempera ture . As the tempera ture i s ra i sed , a t he rma l decomposi-

tion of the e las tomer and fusing of the glass f r i t occur . The weight

of decomposition is a t ime- tempera ture phenomenon that p rog res ses

s lowlya t 800 F and inc reases a s the tempera ture r i s e s , The glass

f r i t does not fuse until 1100 to 1200 F has been reached. Hence,

there i s a range of t empera tures (approximately 800 to 1100 F)

where the e las tomer i s decomposing and the glass f r i t does not fuse.

This represen ts a t ransi t ion phase during which the coating i s mos t

susceptible to damage and the gas permeabili ty i nc reases . When the

coating i s subjected to a heat flux of such a magnitude, i t mus t t r av

e r s e the c r i t i ca l t empera ture range in a relatively shor t t ime. The

g lass f r i t fuses before the si l icone e las tomer decomposes excess -

ively, provides a c a r r i e r for the silicone res idue, and f o r m s an

adequate gas b a r r i e r .

E las tomer coating ma te r i a l s that a r e dpplicable for reducing porosity

in dece le ra tor s t ruc tu re fabr ics a r e l isted and descr ibed in Table

XVII. Each ma te r i a l i s evaluated in t e r m s of i t s performance in a

var ie ty of environmental conditions so the l imitations of the mater ia l

a r e readily apparent ,

Some typical coatings descr ibed by t rade number and name that have

been used o r have been investigated for possible use in dece le ra tors

a r e shown in Table XVIII, along with typical thermal proper t ies of

these mater ia l s . Neoprene, DC- 13 1, and Viton have been used sa t -

is factor i ly on flight- tes ted dece le ra tors in the low- to-medium tern.-

pe ra tu re regime - that i s , up to about Maeh 2 and a t al t i tudes above

SECTION I1 - AERODYNAMIC D E P L O Y A B L E D E C E L E R A T O R S GER-12616

70, 000 ft. The remainder of the l isted coatings a r e potential candi-

dates to extend the operating capability of the state- of- the-ar t fab-

r i c s . In many applications, it may be appropriate to use ablative

coating mater ia l s , which - because of the shor t deceleration t imes

character is t ic of deployable decelerators - need to function only over

a limited t ime period.

The approach used to increase the temperature capability of the

coating between the thermal degradation temperature of the elasto-

m e r and the des i red operational temperature i s to load the elastomer

with a low-melting point inorganic mater ial . As the temperature

r i s e s , a thermal decomposition of the elastomer occurs , and the in.-

organic ma te r i a l changes to a very viscous fluid. The viscous fluid

i s t o have a high-surface tension that will hold the residue of the

elastomer in suspension and maintain a continuous fi lm, Upon cool-

ing, the mater ia l i s to solidify and fo rm a solid gas b a r r i e r that has

a cer tain amount of flexibility, although much l e s s than the original

unfired coating.

f . Joining Methods - The construction of foldable, packageable s t ruc tures involves the

classic problem of building compound shapes f rom plane m a t e r i d .

Aerospace decelerators a r e assembled by sewing a multitude of in-

dividually patterned pieces of a plane fabric mater ial . These pieces

a r e seamed together, usually by sewing with threads of ma te r i a l

s imi lar to the fabric filaments. Ballute gore patterns, for example,

a r e cut on the bias f rom "square" cloth - that i s , cloth that has equal

o r nearly equal strength and elongation in warp and f i l l . Gores a r e

al ternated right and left bias to balance out differences in elongation

in the warp and f i l l directions. So f a r , Ballutes and parachutes a r e

of single-ply construction.

Joining methods include sewing, cementing, and - in the case of

meta l fabrics - spot welding. With plastic f i lm mater ia l , cementing


7k TABLE XVII - RELATIVE GENERAL PROPERTIES O F ELASTOMERS

Natural rubber

- - Teal - B

B C

B

B

A

BC

CD

B C

BC

D

- Abra- sion

AB

AB

B

AB

A

AC

C D

AB

B

D

Impact (fatigue)

- Cold

(stiff)

B

B C

C

C

C

BC

A

C

D

C

- Specific gravity

0. 93

0. 94

0 . 92

1. 24

1. 05 to 1. 17

0. 99

1.25

1.10

1. 40 to 1.85

1. 25 to

Heat Flame I (F)

Styrene butadiene rubber (Buna S or GRS)

Gas re - tention

B

General purpose rubber, not so resilient a s natural , better resistance to aging.

Weather, heat , ozone, chemical, and solvent resistant , low a i r per- meability.

Contact with oil, ozone, strong oxidizing agents.

Contact with oils.

Resistance - oil, weather, chemical

Highly resilient, low hysteresis , general

Isobutylene iso- prene rubber (Butyl o r GR- 1)

Unsuitable for

Contact with oi ls , ozone strong oxidizing agents.

Temperature extremes, contact with aromatic oils and most fuels, long exposure to low temperatures

AB Chloroprene rubber (Neoprene o r GR-M)

Weather resistant, fa i r oil resistance.

Polyurethane elastomers (Adi- prene, Chemigum SL, CX- 1046)

Nitrile butadiene rubber (Buna N)

Contact with s team or hot water

A (R. T. )

Superior abrasion re - sistance, sunlight and ozone resistance, good oil resistance.

Contact with ozone, strong oxidizing agents.

B Medium to good oil r e - sistance, fa i r fuel resistance

Contact with high pressure steam, arematic oils, fuels, abrasion.

B Silicone rubbers Resistant to temperature extremes, fair oil resistance, properties constant f r o m 60 F to 500 F.

Aromatic oils and most fuels.

AB Chlorosulfonated polyethylene (Hypalon)

Weather, heat, ozone, and moderate oil res i s - tance, good color pos- sibilities.

Fluorinated elastomers (Fluorel, Kel- F, Viton)

Organic polysul- fide rubbers (Thiokol. GR- P)

A

Excellent oil resistance, good resistance to a ro- matic fuels , excellent weather and ozone re - sistance.

Resistance to compression s e t particularly a t temperatures above 100 F, uses where mercap- tan odor would be objec- tionable, contact with oxidizing acids.

Resistant to oxidizing acids, fuels containing up to 30 percent aromat- i cs , ozone, weahter; excellent oil resistance.

*source - Reference 93.

Contact with diester lubricants, uses where mater ia l must be easi ly flexed a t temperatures below 0 F.

'A = exceptional, outstanding, o r excellent; B = good; c = fair ; D = poor.

TABLE XVIII - ELASTOMERIC COATINGS

Coating Vendor

Neoprene Goodyear 1137-C

Dow- Corning

Viton Du Pont

CS- 105 Goodyear

0 - 6 5 / Dyna-Therm

RTV-88 General Electr ic

RTV-560 General Elec t r ic

AVCOAT I1 AVCO

DC-325 / Dow-Corning

gravity

-a-

Thermal Emis - Specific heat conductivity 1 sivity

0. 3-0. 35 ~ t u / l b - deg F

0. 395 Btu/lb- deg F

0. 14 ~ t u / h r - f t - deg F

0. 167 a t room tempera ture ~ t u / h r - f t - d e g F

Remarks

Low tempera ture coating

High tempera ture coating

Ablator

Ablator

Ablator

Ablator


i s a lmost invariably involved - either a heat- sealing or solvent-

sealing cementing o r adhesive application. With soft fabr ics , sew-

ing i s usual but cementing i s sometimes practical, especially with

a n elastomer-coated cloth, and frequently resul ts in higher joint ef-

ficiencies. Combinations of cementing and sewing have been used.

Cementing has been for secondary purposes, such a s sealing holes

made by sewing o r preventing the slippage of stitching. As ear l ie r

mentioned, joining of meta l cloth has been by multiple staggered row

spot welding. The Air F o r c e has reported sewing such fabric suc-

cessfully with wi re thread (see Reference 94).

The development of the optimum s e a m for a specific application i s

a mat te r of design and tes t development. Fac tors involved a r e the

cloth and i t s basic s t rength to be developed; the coating, if any; witk~

an orthogonal o r biased seam, etc. Variations possible include nunl-

be r of paral le l rows of s t i tches, number of st i tches per inch, type of

stitch, presence o r absence of reinforcing tapes o r webs, types of

s eam, possible overlay of e lastomeric coating, etc. The final bulkl-

ness of the s e a m i s a consideration with its consequent influence on

packageability and deployment.

Seams a r e invariably a problem a r e a . Seaming represents a sizable

par t of construction cost and contributes significantly to the variation

in quality of the finished ar t ic le . The seam adds bulk and weight,

reduces flexibility, adds distortions when the s t ructure i s loaded,

and almost never can be designed to develop 100 percent mater ia l

strength. Seam design and mater ia l selection go hand in hand.

While cementing can generally develop a s t ructural ly m o r e efficient

joint, i t a l so i s m o r e adversely affected by elevated temperature.

g. Material Selection and Qualification

Materials selected for u s e in a particular decelerator s t ruc ture a r e

the resul t of analyzing both design factors and fabrication technology.

Design factors such a s s ta t ic and dynamic loading, thermal loading,


maximum s ize and weight of strclcture, and aerodynamic drag r e -

q u i ~ e m e n t s dictate the requirements for s t rength and temperature

resis tance. The ma te r i a l selected must meet these requirements

af ter fabric s t rength- to-weight ratio, thickness, porosity, flexibility,

and coatings have been considered. The selection of mater'ial usually

will involve determination of the fiber o r filament ma te r i a l and s ize,

weave, s eam construction, production sequence, and other produc-

tion techniques. Different mater ia l s and fabrication techniques may

be required for the components of the s t ructure.

Current Development in Materials

Anticipated future mater ia l s a r e conventionally woven fabrics f rom

exotic, high temperature- resis tant f ibe r s . Developments to be ex-

pected include eritirely nefi- f ibers , improvements in properties of

existing f ibers , and development of f iner filamentation and tighter

weaving of the newer mater ia l s , such a s the s u p e ~ a l l o y s .

Glass fa br-ics, a s mentioned ea r l i e r , requi re vastly improved inter -

filament abrasion resis tance. Since the g lasses have been subject

to considerable r e s e a r ~ h and development, much improvement i n

this basic character is t ic i s difficult to foresee. Possibly a surface

coating, compatible with other requirements , may yet make possible

the wide use of foldable, flexible g lass fabrics .

'The development of extremely thin s ~ r f ' a c e coatings for oxidation

prevention in re f rac tory metal cloths is e-xpcited, enabling erploi

tat-ion of these rrlclrerials a t high tempera tures .

Other r,ew fiber mater ia l s c ~ r r e n t l y undergoing development a r e

alumina/calcia, silicon carbide, boron, carbonized and graphitized

yarns, and q:,artr,. Development of these and other mater ia l s will

yield some usable fjlaments.

,' The superalloys, such as Rerie 41 and other proprietary formula-

tions, a r e v e r y much in a r e sea rch and development phase, Wire


cloth of filaments a r e fine a s 0. 5 mil has been woven a t considerable

expense. Problems include drawing a much finer fi lament and weav-

ing ve ry dens e fabrics without excessive filament breakage.

The technology of "whiskers" has been of scientific in te res t for some

time. Whiskers a r e pure substances formed f r o m single crystals .

Therefore, they a r e f ree f r o m impurit ies and gra in boundary defects

and represent the theoretical ult imate i n strength character is t ics .

They a l so have s t r e s s levels f a r in excess of their standard mater ia l

counterparts. Materials approaching the extreme s t r e s s levels of

whiskers a r e not soon to be expected.

Elastomeric coatings of fabrics can be expected to improve. The

urethanes and silicone rubbers a r e very promising a t elevated tem-

pera tures . New combination coatings such a s the CS- 105 or Dyna-

T h e r m D-65 coatings, which protect for a limited t ime by chemical

and/or mechanical responses to temperature, can be expected.

Fine meta l filamentation by electroforming, plastic metalizing, va-

por deposition, and cold-drawing i s being investigated experiment-

a l ly ( see Reference 90) and appears promising.

i. Future Development in Materials - /

Woven cloths of Rene 41 provide a substrate-mater ial capability to

1800 F. However, to obtain a capability beyond this point, efforts

must be directed toward the weaving of cloths of the re f rac tory met -

a l s . Until recently, this has appeared to be a ve ry difficult problem;

however, developmental work in weaving meta l fabrics using textile

methods and equipment provides a sound basis f rom which this work

can be ca r r i ed on. Many of the problems encountered and the solu-

tions evolved under Contract AF33 (616)-7854 (see Reference 93) a r e

applicable to the weaving of re f rac tory meta l fabrics .

One problem encountered with refractor ies involves their rapid oxi-

dation a t elevated temperatures . Rapid oxidation becomes especially


cr i t ical when the basic s t ruc tura l element i s a filament with a di-

ame te r of 0. 5 mil . To overcome this problem, oxidation-resistant

coatings a r e required. Although considerable effort i s being ex-

pended in this a r e a , i t i s being directed pr imari ly toward the pro-

tection of sheet stock, castings, and the like. Some of the coatings

developed for g ross par t s can be adapted to the protection of fila-

ments , but specific r e s e a r c h for the protection of fine refractory

metal filaments i s needed. Processing and fabrication techniques

for t reated o r coated refractory metal cloths a l so must be estab-

lished.

Another possibility for extending the subs t ra te -mater ia l tempera-

ture resis tance capability above 1800 F lies in the use of carbon o r

graphite cloths. Recent efforts show marked improvements in fab-

r i c s woven f r o m these mater ia l s ; however, considerable r e sea rch

and development a r e required to improve the strength- to-weight r a -

tio, abrasion resis tance, and handling capabilities of these mater ia l s .

Unfortunately, most of the research and development effort expended

on these mater ia l s i s directed toward their u se in rigid laminations,

Such effort does not tend to solve the peculiar problems attendant on

their use a s a flexible mater ia l .

Basic mater ia l s for use in the substrates a t temperatures above

1800 F a r e available. 'The p r imary problem in the use of these m a -

te r ia l s involves working and fabricating them into basic s t ruc tura l

ele.ments f r o m which decelerators can 'be fabricated.

Coating mater ia l s present another problem. There a r e no flexible

coating mater ia l s that have temperkture-resis tance capabilities

above 1500 F. As previously s tated, CS- 105 coating i s operational

to 1500 F within cer tain l imits . Under Contract AF33(616)-7853,

efforts to improve this coating and extend i t s capability were under-

taken. It was found that some or" the coatings developed had superior

character is t ics over ve ry limited ranges, but that CS- 105 was su-

per ior overall ,


Research i s being conducted under an Air Force contract to extend

the capability of CS-105 to 2000 F and to examine other concepts for

high--te.mperature coatings. This a r e a of investigati.on requires con-

siderable future effort, since the development of satisfactory flexi-

ble, high-temperature, impermeable coatings lags the development

of substrate mater ia l s that can be used in the same temperature

range.

Although cemented seams in decelerator s t ruc tures can be very ef -

ficient, especially with elastomer-coated fabr ics , no cements a r e

available that have acceptable c reep and strength character is t ics

beyond 180 to 200 F. The development of high-temperature cements

with the proper bonding charac ter i s t ics would provlde increased lati -

tude in design and fabrication of s t ruc tures .

G E R - 12616

SEC TlON IiI - DES1G.N DISC'USSION

1. SYS'TEM DESIGNS AND LOGISTlCS SEQUENCING METHODS

Exclusive of obtaining design c r i t e ria. to define design requ i rements fo r

specific high-speed r ecove ry applications, a l l previous f i r s t - s t age re-.

covery sy s t ems have the following s e q ~ e n c i n g methods in common:

1. Automatic initiation

2 . Deployment p repara t ion , which consis ts of auto-

ma t i c can i s t e r opening; can i s te r opening consis ts

of sequencing disconnects ( la tches , cu t t e r s , pin-

pu l le r s ) , which void the can i s t e r exit of a l l r e s t r i c -

tions

3 . Automatic deployment initiation (utilizing e i ther a

t h r u s t e r , m o r t a r , o r drogue-gun sys t em)

4. Automatic dece l e r a to r inflation

5. Automatic dece l e r a to r r e l ea se i n p repara t ion fo r

f inal- s tage s y s t e m deployment

F igure 66 shows a typical deployment sequence. These components a r e

in terconnected and energized e i ther e lec t r i ca l ly o r mechanical ly .

Exper ience has proved that the u s e of ordnance devices such a s th rus t -

e r s , drogue guns, m o r t a r s , and bal l i s t ic disconnects was the be s t method

to obtain adequate s y s t e m operat ion. The pyrotechnic devices have m e t

the following requ i rements :

1. Lightweight

2 . Function i n a high-g environment

SECTION I11 - DESIGN DISCUSSION GER-12616

A. FORCIBLE DEPLOYMENT INITIATlON

DROGUE-GUN SLUG

D E P L O Y M E N T BAG AND STOWED D E C E L E R A T O R

B . AT LINE S T R E T C H , BAG PEELS

OFF D E C E L E R A T O R

C. D E C E L E R A T O R INFLATED WITH RAM AIR,

L3EGIN.S TO SLOW THE VEHlCLE

--

D. D E C E L E R A T O R RELEASED IN PREPARATION

FOR FINA1.-STACE LANDING-DEVICE

DEPLOYMENT

F i g u r e 66 - Typical Recovery -Sys t e m Deployment Sequence

SECTION I11 - DESIGN DISCUSSION GER-12616

3 . Function positively and forcibly

4. Function in extremely short periods of t ime

Basic problems with pyrotechnics a r e their sensitivity to heat and their

dependence on sma l l variation in power supply e lec t r ica l cur rent require-

ments. The major problem i s the stringent minimum weight and stowage

space requirements. Additional standardization of component design a lso

would aid in easing sys tem design problems.

Table XIX summarizes the type of hardware, function, and method of op-

eration.

The inflation mechanisms described in Table XIX a r e required when self-

inflation i s not feasible. For example, closed p res su re vessels such a s

spheres o r f lared sk i r t s require some type of inflation device a t any de-

ployment altitude; even r am-a i r - inflated devices such a s parachutes and

Ballutes may require supplemental inflation devices a t extremely high al-

titudes (above 200, 000 f t ) .

2; DESIGN PROCEDURES AND CRITERIA

a . General - The available dece lera tor -sys tem design cr i te r ia , which a r e a mea-

surement of the state of the a r t , a r e clear ly dependent on available

performance and design parametr ic data.

b. Pre l iminary Design Procedure for Supersonic Decelerator - Figure 67, taken f rom Reference 27, shows the significant parame-

t e r s that a r e evaluated to obtain a prel iminary design.

The major design effort consists of an operational computer t ra jec-

tory study, a n aero thermal parametr ic analysis, and a s t ructures

and weight study to meet these aero thermal performance require-

ments . Examples of key design parameters that must be evaluated

and how they a r e interdependent on each other follow.

I t em no.

1

2

3

4

TABLE XIX - SEQUENCING HARDWARE

Function

System initiation

Deployment prepara t ion

Forc ib le deployment of the dece l e ra to r

Decelera tor inflation

Type of hardware

"Q" senso r

Ba romet r i c s enso r

"G" sensor

T i m e r

Telemetry

Release mechanics such a s explosive bolts, cu t t e r s , pin pul le rs , la tches, c lamps , etc . , and arming devices

Mor tar

Drogue gun

Thrus t e r

Nitrogen bottle

Gas genera tor

Sublimating powder

Vaporizing liquids

Method of operat ion to obtain e lec t r ic signal

Measures a given p r e s s u r e difference between s ta t ic and total head.

Measures a given p r e s s u r e difference between s ta t ic and sea level a tmosphere .

Measures a given amount of s t r a i n in a cantelever deflected under the iner t ia l loads.

Mechanical o r e lec t r ica l clock.

Telemetry signal f r o m external sou rce

Pyrotechnic charge provides energy to seve r bolts o r retaining s t r a p s , o r to unlatch can i s t e r door s , o r to a r m subsequent sequencing devices.

Pyrotechnic charge burns and provides high p r e s s u r e gas to f i l l a blast bag beneath the stowed dece le ra to r . The dece lera tor i s displaced and ejected out and aft of the canis te r .

Pyrotechnic charge burns inside the gun and e jec ts a slug aft . The slug i s bridled to the dece le ra to r , and the kinetic energy of the slug ~ u l l s the dece le ra to r f r o m i ts canis te r .

Pyrotechnic charge burns inside the th rus t e r ejecting the thrus ter cylinder, canis te r , and dece le ra to r af t .

1 High p r e s s u r e ni trogen gas i s r e l eased by a pyrotechnic valve inflating the dece lera tor . ' Pyrotechnic charge burns and provides high p r e s s u r e , gas to f i l l the dece lera tor .

I

, Solid powder subl imates , upon experiencing the ex- t r eme ly low stat ic p r e s s u r e s a t high al t i tude, and gases a r e generated to inflate the dece lera tor .

Liquids such a s alcohol vaporize, which provides the gases to inflate the dece lera tor .

ALTITUDE, VELOCITY,

M A T E R I A L

AND PACKAGE VOLUME

I

SECTION I11 - DESIGN DISCUSSION GER- 12616

1. The descent init ial conditions (altitude, ve-

locity, W / C ~ A , flight angle)

2 . The bal l is t ic coefficient a f te r dece le ra tor de-

ployment ( w / c ~ A )

3 . The drag a r e a , which i s influenced by the s i z e

and d rag coefficient (efficiency)

4. The drag coefficient (C ), which i s influenced D by x/d (towline length divided by the payload

d iameter ) , ~ / d (decelerator d iameter divided

by the payload 'diameter) , and the dece le ra tor

nose shape

The problems of accurately forecasting drag due to the forebody wake

flow around the towed dece le ra tor and the importance of the towed

pa rame te r s x/d and ~ / d have been discussed in detail. Because of

this , and until such t ime a s m o r e basic r e s e a r c h i s conducted, ex-

per imental t e s t s , if for no other reason, a r e required to obtain a

given amount of steady- s ta te drag for a given high- speed applicatior.

The following factors affect the s t ruc tu ra l and weight design:

1. The peak loading condition, which i s influenced

by a l l performance pa rame te r s

2 . The peak s t r e s s condition, which i s influenced

by the loading, s ize , and shape of the dece le r -

a to r

3 . The s t ress- to-weight ra t io , which i s influenced

by the aerodynamic-heating tempera tures and

the type of ma te r i a l s selected

4. The weight of the dece le ra tor , which i s influ-

enced by the design pa rame te r s plus the m i s -

cellaneous hardware weights such a s the infla-

tion sys tem, i f required

SECiT:TON ,111 - DESIGN D1SCUSSSON GER-12616

c . AvaiPa ble Design Data for Dynamic Deployment Loads - --

it i s evident that the decelerator mus t be designed to support a l l ad-

v e r s e loading conditions that occur during i t s period of opepation.

Ln most applications, this load i s the opening- shock load that occurs

c l ~ r l n g deployment. As was indicated in the discussion of Table XI,

the available dynamlc shock- load data f r o m supersonic demonstra -

tions a r e extremely l imited. However, despite this l imitation, these

data show that a sat isfactory design i s a compromise between (1)

sho r t decelerator- inf la t ion t imes that minimize fabr ic-f lut ter loads

during inflation a t the expense oi higher shock load levels and ( 2 )

long dece le ra tor inflation t imes that minimize shock load levels a t

the expense of longer- duration fabr ic-f lut ter loading.

As i s shown in Reference 1 , subsonic- flight regime parachute design

and t e s t experience have proved that the peak opening- shock load can

be related to dynamic p re s su re . Ln this case , i t i s called the "canopy

loading' and is the product of dynam:c p r e s s u r e and openlng- shock

i a c t o ~ . This opening-shock factor va r i e s with type of canopy, a l t i -

tude of deployment, and weight of the payload. However, even in

t h ~ s wel l - known a r e a of subsonic parachute applications, shock-factor

data a r e l imited to "infinite-mass '! conditions, where for a l l pract ical

purposes the payload does not slow down during para chute opening.

1:1 s u m m a r y , to fill these vo-lds, i t i s recommended t-hat a design

evaluation consider the following procedures to determine the peak

design loads:

I . Utilize subsonic opening- shock fac tors as par

t ial evidence t,o foreca a t supersonic deployment

loads.

2 . Ob ta in t r ans i en t - loadexpe r imen ta l d a t z f r o m

tes t s s i m i l s ~ to new applications.

SECTION 111 - DESIGN DISCUSSION GER-12616

3 . Evaluate inflated- decelerator steady- state

loads along the required t rajectory.

As Table XI shows, available documented dynamic-load data a r e

limited to deployments below Mach 4.

Even though a procedure i s s e t up to determine the peak design load,

better experimental information is s t i l l needed for a m o r e accurate

definition of peak loads.

SECTION JV' - DATA CONFIDENCE - --

1. GENERAL

Confidence in previous t e s t data to be ulsed fo r any reason i s mandatory.

In lieu of the u s e r finding complete data for subsequent utilization in a

new design application, the following evaluation procedures that have

been used In the past will aid in increasing the level of confidence that

specific aerodynamic data a r e valld. Some of the problems of s imi la r i ty

and model design dlso will be disc-assed.

2 . SIMILARITY' C R I T E R ' U

The pr ime requirement for any trail ing drag device that depends on dy-

namic p r e s s u r e l o r inflation i s that i t opens o r inflates and remains open

and maintains its geometr ic shape over the full range of operational con-

ditions. Unfortunately, the opening tendency of a parachute depends on a

complex of variables that cannot be completely reproduced in the wlnd

tunnel. Although sca le i s the main factor , Reynolds number alone does

not appear to be a n adeqilate c r i t e r i a of slrnilari ty. Based on ve ry l imited

free-fl ight data, ~t i s b e l ~ e v e d that successf-a1 operation of a sma l l sca le

model in the wind tunnel gives no ass-clrance thst the full sca le model will

a l so open and r ema in open a t the s a m e Reynolds number . F o r this r ea

son, scaling effects mus t be determined f rom wind tunnel testing to a s c e r -

tain the efiect of var-ioua pa rame te r s on the successful operation of the

full scale c o n f ~ g u r ~ t i o n jn i r e e flight,

Apar t f r o m differences ir, relative flexibility of struct; lre, surface rough-

nes s , and effective poroszty, i t is a l so believed that the behavior of She

model i s different f r o m fill1 s cale becd Ise oi the s t rong effect of sma l l

differences in local fiow along the canopy of a parachute. Combined

SECTION IV - DATA CONFIDENCE GER-12616

canopy pulsing and longitudinal vibration have been encountered in both

wind tunnel and f r e e flight but may be magnified in the wind tunnel.

Inflatable dece le ra tors that a r e dependent on self-contained p r e s s u r e

sys tems o r a r e r a m - a i r inflated do not have the s a m e inflation problems

a s parachutes that a r e dependent on the magnitude and stabil i ty of the dy-

namic p r e s s u r e of the surrounding fluid. Absent f rom these configura-

tions a r e the problems of local flow perturbations, which can cause squid-

ding o r violent fluttering.

3 . FLEXIBILITY AND STRENGTH

Small sca le wind tunnel models a r e likely to be relatively l e s s flexible

than the full sca le prototypes unless special precautions a r e taken in de-

ta i l design. As a min imum fo r approximation of aeroe las t ic s imilar i ty ,

the unit s t rengths of the textile used should be a t the s ame rat io to applied

loads a s to those of the f u l l s a l e dece le ra tor . Therefore , i t i s neces sa ry

e i ther to es tabl ish full scale loading c r i t e r i a o r to define c lear ly the full

sca le loading c r i t e r i a represented by the models . The s t rength of m a -

t e r i a l s to be used i n the models will depend on the dynamic p r e s s u r e

range of the wind tunnel a s wel l a s that on a scale of the model.

The scaled-down, wind- tunnel inflated models will not likely have fabr ic

texture , thickness, cel l s t ruc tu re , and smoothness in proportion to the

full scale device. The wind tunnel models will probably re ta in a st iffer

o r relatively m o r e solid shape. No analysis of the effects of re la t ive

solidity of shape appea r s to be available, but i t i s es t imated that this

effect would be quite smal l .

4. SURFACE TEX'I'URE

Surface roughness, pores , and c r i m p r idges of texti les usually cannot

be scaled down to s m a l l model dimensions and so may influence aerody-

namic proper t ies result ing f r o m skin frict ion and boundary layer consid-

erat ions . Within l imi t s , the models can be assembled with scaled s e a m s


and proportionately f iner threads, but nar row hems and s earns generally

tend to be relatively coa r se and rough. Surface tcxture and roughness

affect the nature of the boundary layer and Locatiorl of boundary layer

transit ion. Depending on known differences between wind tunnel model

and full sca le device surface conditions, a drag correct ion f o ~ relative

grain s i ze may have to be made in conjunction with the Reynolds nurrlber

drag correct ions . This cor rec t ion would be s imi l a r to that applied to

mi s s i l e models .

5. DYNAMICS

Unstable model configurations a r e difficult to m e a s u r e not only because of

their effect on the tunnel balance sys t em b-ut a l so because they tend to

disintegrate in a ve ry shor t run t ime, Means of effectively damping mor.iel

vibrations without otherwise affecting performance ar t : great ly to be de-

s i r ed . Another res t r ic t ion that has yet to be evaluated f rom a dynamics

point of view i s the infinite payload m a s s condition usually associated wi7.h

wind tunnel testing ve r sus the finite conditions of flight.

The above discussion i s mainly concerned with the correla t ion between

wind tunnel data and f r ee flight data . Equally important i s to be able to

cor re la te between theory, wind tunnel, and flight. Theoret ical ver i f ica-

tion has again been great ly neglected.

Until s ta t i s t i ca l type flight data a r e accumulated and be t te r means of r e -

cording and reducing flight data a r e available, engineering judgment mus t

be employed. An example of relying on one sys tem for obtaining flnal r e -

sults i s shown in Figure 68. Here, curve "A" represen ts the drag coef-

flcient data obtained by r ada r tracking and cupve "B" the drag coefficient

data obtained by te lemetry. The data shown in this f igure w e r e reduced

f rom the resu l t s of two Ballute flight t e s t s . In the ca se of curve "A, " smal l e r r o r s in displacement measurements were magnified in the dif-

ferent integration p roces ses for determining the velocit ies and acce l e r -

ation. E r r o r s a r e fur ther magnified when these calculated velocities

2 4

2 0

1 6

1 2

0 8

0 4,

0 U

0 I

0 8 1 0 1 2 1 4 1 6 1 8 2 0 2 2

MACH NUMBER

I


(which must be squared to obtain the dynamic p res su re ) and acceleratior.

values a r e used to calculate drag coefficient. Curve B data a r e believed

valid since the drag resul ts in wind tunnel tes ts of basic s imi lar cone

models showed s imi lar drag coefficient values. This example i s not

shown to indicate that radar tracking i s a poor method of obtaining drag

coefficient resul ts but only to point out the need for careful data reduction

procedures.

SECTION V - PRESENT HIGH-SPEED RECOVERY TECHNIQUES,

PROBLEM AREAS. AND VOIDS

1. GENERAL

The discussion up to this point has dealt with the available data in the

different categories of aerodynamics , thermodynamics, and s t ruc tura l

design. The intent of this section i s to discuss and to co r r e l a t e this data

in light of present-day requirements for supersonic dece le ra tors , thus

pointing out the basic problem a r e a s and voids i n the existing technology.

These genera l flight spec t rum requirements and associated genera l ae ro -

thermal loading levels result ing a r e shown in Figures 1 and 2 .

2 . PERFORMANCE LIMITS

A review of Tables I through X reveals that common r e s e a r c h objective

to find decelerator sys t em configurations that will mee t a broad recovery

flight spec t rum ( see Figure 1 ) ; namely, recovery of heavier payloads

f r o m higher speeds (and/or higher ae ro the rma l loadings) and alt i tudes.

Towed nonporous textile dece le ra tors u p to five feet in diameter have

been successfully flight tes ted up to deployment speeds of near ly Mach 4.

In this ca se , a successful t e s t means that the dece le ra tor performed in

a stable manner and produced high drag without s t ruc tura l fa i lure . The

implication of the high drag-producing flights without fa i lure i s a s follows:

1 . Models were fully inflated.

2 . Models did not experience any significant cycle

breathing (buzzing) a f te r deployment and inflation.

3 . Tempera tures encountered were l e s s than 600 F

design condition l imit (of coated textile fabr ics ) .

-- Preceding page blank '!I:'

SECTIONV-TECHNIQUES, PROBLEMAREAS, ANDVOIDS GER-12616

P r i o r to these flight t e s t demonstrations, me ta l cloth nonporous blunt

body models w e r e successfully tes ted i n wind tunnels up to Mach 10 and

textile models up to Mach 6. These tes t s indicate that sa t isfactory a e r o -

dynamic performance can be obtained. Since wind tunnel r e s e r v o i r a i r

i s cooled and dr ied, these past wind tunnel t es t s do not demonstrate the

dece l e ra to r ' s capability to withstand the rma l environments anticipated

above Mach 3 for m o r e than a few seconds. T rack tes ts have been a c -

complished using approximately four-foot models with deployments a t

Mach 1. 4 and q ' s up to 2400 psf. This Mach 3 value, a s a l imit , i s men-

tioned since equil ibrium stagnation tempera tures that would be encount-

e r ed i f the sys t em i s allowed to t rave l a t that speed for any length of tirr,e

i s above the s t ruc tu ra l l imit of texti les. Hence, a textile dece le ra tor

sys t em for deployment above Mach 3 m u s t be designed ei ther to slow the

payload down quickly to prevent overheating o r to provide the fabr ic s t ruc-

tu re with additional protective devices s o the basic fabr ic does not exceed

the allowable 600 F l imit . Ln the above mentioned flight t es t , the forme.?

condition existed where the dece le ra tor was of sufficient s i ze to slow the

payload and itself down to Mach 3 in a few seconds to avoid the excessive

heat.

Successful supersonic performance of porous dece le ra tors - namely,

parachutes - has been limited. While sma l l wind tunnel models ( less

than one foot in d iameter ) did develop drag up to Mach 6 and four- to

six-foot wind tunnel and flight models developed d rag up to and between

Mach 3 and 4, model coning instability and canopy inflation insta.bility

were encountered when operating above Mach 2 . 5. Evidence that this

deter iorat ion in aerodynamic performance during increasing Mach-num-

be r tes t s of the bet ter-performing geometr ic openness parachutes was a s

follows :

1. Transonic steady-state drag coefficient (C ) was

between 0. 4 and 0. 5. Do

2. Above Mach 2 . 5, the drag coefficient (C ) was

between 0 .2 and 0 .35. Do

SECTION V - TECHNIQUES, PROBLEM AREAS, AND VOIDS GER- 12616

Section I1 detailed the possible reasons for this performance variation.

In summary , parachutes were extremely sensit ive to the changeable

wake of the towing forebody. Based on this survey data, the be t t e r -pe r -

forming models were the Parasonic and the reefed ribbon configurations.

These data were l imited to wind tunnel resu l t s only. In this ca se , bet ter

performance i s defined a s minimizing coning instabil i ty and canopy

breathing and a l so obtaining a m o r e fully and m o r e constant inflated

shape. The combined effect of providing a known (cal ibrated) amount of

choking plus the isotensoid membrane design shape i s believed to be the

reason for the improved performance. The Parasonic canopy crown was

coated to obtain the proper porosity. Thus, coating a l so has extended

the thermal environment capability by one o r d e r of magnitude.

The other configuration that performed up to Mach 3 with a minimum of

canopy breathing and coning instability was a reefed ribbon configuratior~

(either the hemisflo o r the conical ribbon type). The combined effect of

lowering the geometr ic porosity m o r e than 1/2 of that of the previous

ribbon parachutes , plus the reef shape being a stable conical configura-

tion, was believed to be the reason for the improved performance. It i s

important to note that the Mach 3 condition was the highest speed tested

and in this case not necessar i ly the performance l imit .

In summary , the survey found considerable experimental aerodynamic

s teady-sta te drag resu l t s that did indicate the aerodynamic capability of

deployable dece le ra tors performing sat isfactory in the supersonic and

hypersonic speed ranges. However, to s ay that the s ta te of the a r t i s

such that there i s adequate performance in design information available

to design a lightweight sys t em for future application i s not the case .

Even i n the Mach 1 to 5 speed range, the m o r e easily obtained steady-

s ta te drag information i s f ragmentary . F o r example, there i s no one

configuration o r even a c lass of configurations that has been tes ted over

a complete range of Mach numbers and Reynolds numbers . Above Mach

5, with few exceptions, the available drag data a r e a complete void. In

SECTION V - TECHNIQUES, PROBLEM AREAS, AND VOIDS GER-12616

addition to lack of data, a basic phenomenon not yet completely under-

stood i s how the forebody wake flow affects the towed decelerator that

must operate in that wake. When this flow i s m o r e fully understood in

the wake, not only will the design have better forecas t aerodynamic per -

formance but a l so will have bet ter forecast thermodynamic performance

Other a r e a s that the survey showed a s problem a r e a s and voids a r e a s

follows :

1 . Ext reme shortage of cyclic steady- s ta te data

2 . Extreme shortage of transient deployment data

3 . Extreme shortage of dynamic stability data

Because of the dynamic t ime dependent propert ies of the forebody wake

acting on the towed decelerator in this wake, cur rent acceptable dynamic

and s tat ic stability coefficients do not appear adequate to descr ibe the

motion of a decelerator ( see Section 11, Item - d).

3 . STRUCTURESANDMATERIALS

The vast majori ty of supersonic decelerators that have been tested have

been made of woven nylon or Nomex (high temperature nylon) fabrics .

The selection of these fabrics was due to previous usage, cost, and be-

cause these fabrics had the physical propert ies that best matched the

operational requirements. These requirements were lightweight, pack-

ageability, severe dynamic transient deployment loadings, and high level

steady s tate inflation loading (under hostile temperature environment).

Because textile mater ia l s - namely, Nomex - have a temperature r e s i s t -

ance s t ruc tura l l imit of slightly higher than 600 F and because flight tem-

pera ture requirements a r e increasing considerably beyond 600 F, addi-

tional r e sea rch and development mater ia l investigations have been and

a r e being conducted.

Two basic methods of attack a r e being used. One method, which will

hopefully aid in solving the immediate needs for higher operational

SECTION V - TECHNIQUES, PROBLEM AREAS, AND VOIDS GER- 126 16.

t e m p e r a t u r e s , is to p ro tec t the bas ic subs t r a t e (Nomex) with s i l icon o r

f luoro- e l a s t o m e r coatings plus providing a coating additive that would in -

c r e a s e the operating t empe ra tu r e l imi t to about 1000 F. The o ther

method i s to develop new coated m a t e r i a l f ab r i c s such a s f i be rg l a s s ,

s t a in less s t ee l , and supera l loys . The appa ren t potential of the m a t e r i a l s

i s a s follows:

1. F ibe rg l a s s operat ing range - 600 to 1000 F

/ 2 . Sta in less s t e e l and Rene 41 - above 1100 to 1800 F

3 . Refrac to ry m e t a l s - above 1800 F

4. Carbon o r graphi te - above 1800 F

The m o s t advanced of these newer m a t e r i a l s a r e s t a in less s t e e l and / / Rene 41. Rene 41 dece l e r a to r s have been fabr ica ted and tes ted i n the

wind tunnel a t Mach 10 and a t t empe ra tu r e s u p to 1500 F.

Increas ing t empe ra tu r e s above the p r e sen t -day texti le des ign l imi t s wil l

p r e sen t the following m a j o r p rob lem a r e a s :

1. Higher heat r e s i s t an t m a t e r i a l ha s a high modulus

that r e su l t s in l e s s flexibility and c r e a t e s weaving

problenls plus lower foldability and lower dynamic

s t r u c t u r a l loading capabil i ty.

2 . The ab ra s ive cha r ac t e r i s t i c s of f ibe rg lass y a r n s

cause se l f -des t ruc t ion on the flexing and pulsating

loads .

3 . Refrac to ry me ta l s exper ience rap id oxidization a t

high t e m p e r a t u r e s and hence oxidization r e s i s t ance

coatings a r e requ i red .

4. T h e r e i s a n e a r void i n the development of low t em-

p e r a t u r e - 600 t o 1200 F - ab l a to r s (coat ings) .

In addition to the p roper se lect ion of the bas ic dece l e r a to r f ab r i c , the

SECTION V - 'TECHNIQUES. PROBLEM AREAS. AND VOIDS GER- 12616

operat ional requ i rement fo r providing a lightweight dece l e r a to r can be

achieved with the p rope r s t ruc tu r a l design. As new m a t e r i a l s a r e de-

veloped, design p a r a m e t e r s wil l have to be re-evaluated a s to the over - a l l shape a n d s i ze , the se lect ion of s t r uc tu r a l s e a m s , a t t achments , fit-

t ings, and inflation methods.

4. PROBLEM AREAS AND VOIDS

The re i s v e r y l l t t le exper imenta l o r analyt ical ae rodynamic , thermody-

namic , o r s t r u c t u r a l data available in the superson ic and hypersonic

speed ranges . The re i s a gene ra l lack of analytical methods to de sc r ibe

bas ic phenomena, including lack of aerodynamic data over a range of

Reynolds number ; a complete lack of quantitative exper imenta l dynamic-

stabil i ty data ; and a bas ic lack of understanding of forebody wake flow

when influenced by a towed dece l e r a to r . Speclfic problem a r e a s a r e de-

s c r i bed below:

1. The ae rodynamic and thermodynamic per formance

of promi sing dece le ra to r configurations has not been

investigated f r o m the t ransonic reg ime to the hyper -

sonic reg ime. Analytical techniques have not been

verif ied exper imental ly i n the a r e a s l i s t ed below:

a . Drag cor re la t ion , Mach number , and Reynolds numbe r

Shock and boundary layer in teract ion

b. The effects of geomet ry and s i ze

2 . Per fo rmance and load density flow

a . Applicable s imi l a r i t y p a r a m e t e r s have not been es tabl ished

b. The effectiveness of f r e e s t r e a m Reynolds number , Knudsen number , e t c . , has not been de te rmined

3 . The format ion and development of the wake have

not been thoroughly investigated

SECTION V - TECHNIQUES, P R O B L E M AREAS, AND VOIDS G E R - 12616

Dece le ra to r per formance in compress ib le t u r - bulent wakes has not been determined, the effec t s of Mach number and f r ee - s t r e a m Rey- nolds number have not been de te rmined , and payload s igna tures need to be defined. The effects of payload geomet ry , boundary l aye r , and separa t ion on the cor re la t ion p a r a m e t e r s have not been defined. Complete effects of ~ / d and x/d on per formance a r e lacking. The effects of the dece l e r a to r i tself on the wake in- t e rac t ion have not been studied completely, and the local. flow the rma l p roper t i es have not been completely defined.

4 . The stabil i ty of var ious fundamental dece le ra to r

shapes i s not known

a . Stat ic stabil i ty and dynamic stabil i ty der iva- t ives need to be de te rmined

b. The stabil i ty of towed body sys t ems needs to be studied

c . Quantitative stabil i ty s tandards need to be es tabl ished

d. Inflation and breathing stabil i ty have not been adequately descr ibed

5. Heat t r ans f e r cha rac t e r i s t i c s in complex dece le r -

a t o r shapes a r e an unknown I

6 . Methods of determining hea t t r ans f e r in texti le de-

c e l e r a to r s need to be investigated

a . Low t empera tu r e abla t ive m a t e r i a l for application to texti le dece l e r a to r s f r o m 600 to 1500 F i s m i s s ing

b. Various methods of cooling and evaluating the re la t ive m e r i t s of each have n o t been invest i - gated

7 . Lack of exper imenta l data of r e s i s t ance to a b r a s -

ion f r o m high- speed f lu t ter

8. Lack of exper imenta l data of r e s i s t ance to shock

loading

SECTION V - TECHNIQUES, PROBLEM AREAS, AND VOIDS GER- 12616

9. Lack of high t empera tu r e cements

10. Lack of high t empera tu r e coatings

1 1. Gaps i n avai lable m a t e r i a l s between Nomex and

super a l loys

12. Lack of methods of fine w i r e drawing and weaving

The resu l t s when obtained to sa t i s fy these voids (both exper imenta l and

analyt ical ) need then to be co r r e l a t ed with f ree-f l ight r e su l t s .

SECTION V I - CONCLUSIONS

1. GENERAL

The s ta te-of- the-ar t survey considering the operational performance

l imits demonstrated by tes t s indicated the following conclusions:

1. Towed nonporous textile dece le ra tors up to 5-ft in

diameter have been successfully flight tested up to

deployment speeds of near ly Mach 4; 10-in. diame-

t e r me ta l f ab r i c models have been wind tunnel tes ted

successfully up to Mach 10.

2 . Four - to six-foot wind tunnel and flight parachute

textile models developed drag up to Mach 4, a l -

though some instability was encountered above Mach

2 . 5.

The s ta te- of- the-ar t survey of the individual disciplines affecting these

operational performance l imits described ma jo r problem a r e a s , which

a r e given in Items 2 and 3 , below.

2 . AERODYNAMICS

The s ta te -of - the-ar t survey discussed these problems pertaining to ae ro -

dynamic s :

1. The re i s a genera l lack of drag data above Mach 5

and incomplete data below Mach 5.

2 . The basic wake flow phenomenon i s not completely

understood.

3 . There i s a complete l a c k o f d y n a m i c s tab i l i tyda ta .

SECTION VI - CONCLUSIONS GER-12616

3. STRUCTURES AND MATERLALS

The s tate- of- the-ar t survey described these problems pertaining to s t ruc-

tures and mater ia l s :

1. Textile ma te r i a l models have a proved s tructural

resis tance to a temperature l imit of 600 F.

2 . Metal fabr ic models have been tested in the

wind tunnel up to 1500 F.

3 . Proved mater ia l s a r e available for future model

developments f rom 300 to 600 F (textiles) and

f rom 1000 to 1500 F (superalloys). There i s a

complete void for suitable proved mater ia l s be-

tween 600 to 1000 F and above 1500 F.

LIST O F SYMBOLS

Aerodynamic

A(S) = re fe rence frontal a r e a

A. = parachute canopy open inlet a r e a 1

A = parachute canopy open exit a r e a e

>k A/A = cross -sec t iona l a r e a of s t r e a m tube divided by

c r i t i ca l choked flow (nozzle) a r e a

S = re fe rence sur face a r e a

S = parachute canopy total enclosed surface a r e a 0

D = dece le ra tor reference diameter

d = forebody re fe rence d iameter

D = parachute constructed d iameter C

D = parachute inflated d iameter P

D = parachute nominal, d iameter based on So 0

C,, = drag coefficient, F / ~ A

CD = parachute drag coefficient based on Dc

C

C = drag coefficient result ing f r o m p r e s s u r e drag Df on the body foward of the body base

C = parachute drag coefficient based on D Do

0

= parachute drag coefficient based on D P

LIST O F SYMBOLS GER-12610

F = drag fo r ce

L = lift f o r ce , no rma l to Mind

8 = represen ta t ive body length

N = n o r m a l fo r ce

M = moment

M = f ree -s t ream Mach-number 03

q = dynamic p r e s s u r e

q(q ) = f r e e - s t r e a m dynamic p r e s s u r e 03

CA = axial f o r c e coefficient

C~ = lift coefficient, L / ~ A

C~ = n o r m a l fo r ce coefficient, N / ~ A

C~ = moment coefficient, M / ~ A L

C ( C ) = p r e s s u r e coefficient, C p =. pL - P~

p = p r e s s u r e

pL = local p r e s s u r e

p a = f r ee - s t r e a m s t a t i c p r e s s u r e

C = base p r e s s u r e coefficient P~

C p = su r f ace p r e s s u r e coefficient 0

LIST O F SYMBOLS G E R - 12616

q ' = pi tch r a t e

R = body nose radius

rb = body base radius

u velocity in x di rect ion

V = velocity

x = tow-line length between forebody and t ra i l ing af te rbody

X = longitudinal d is tance f r o m - apex to cen te r of C P p r e s s u r e

cp = cen te r of p r e s s u r e

F R = f ineness ra t io , body length divided by body d i ame te r

Re = Reynolds number @ & v / ~

A s = mean f r e e path behind shock wave

p(p ) = f r e e - s t r e a m a i r densi ty 03

pS = densi ty behind shock wave

CY = angle of a t t ack

& = dcY/dt

8 = pitch angle

LIST O F SYMBOLS GER- 126 16

88 = momentum thickness

Bs = cone semiapex angle, f l a r e angle

p = fluid dynamic v i scos i ty

CT = wake thickness

, Thermodvnamic

A = ori f ice s ta tus c ro s s - s ec t i ona l a r e a .a*

A'" = ori f ice throat a r e a

C = local f r ic t ion coefficient f

.*, *a-

c = cha rac t e r i s t i c or i f ice velocity

c = specif ic heat of m a t e r i a l

c = specific heat of air a t constant p r e s s u r e P

D = dece l e r a t e r d i ame te r

I3 = ori f ice th roa t d i ame te r t

G(S) = local f o r m fac tor

g = gravi ta t ional constant

h = hea t - t rans fe r coefficient

h = adiabat ic wal l enthalpy aw

h = cold wal l enthalpy C W

h = wall enthalpy W

k = t he rma l conductivity

P = p r e s s u r e


P = to ta l p r e s s u r e t

P' = local p r e s s u r e

P = f r e e - s t r e a m s t a t i c p r e s s u r e a3

< = heat flux r a t e

4C = heat flux a t S / R ~ = 1 without forebody

I

90 = heat flux a t stagnation point without forebody

0

qw = wall heat flux

qcw = cold wal l heat flux

R = dece l e r a to r nose radius 0

r ' = local rad ia l coordinate

r = radius of roof e lement e

S = su r f ace dis tance with mer id iona l d i rect ion f r o m the stagnation point

S ' = local su r f ace dis tance f r o m the dece le ra to r equator

T = local t empe ra tu r e

TC = t empe ra tu r e a t S / R ~ = 1 without forebody

T = t empe ra tu r e a t the stagnation point 0

T = m a t e r i a l t empe ra tu r e W

T = adiabatic wal l t empe ra tu r e aw

u ' =: local velocity

y = depth

L I S T O F S Y M B O L S G E R - 1 2 6 1 6

Pr = Prand t l number

CY = t h e r m a l diffusivity

8 = th ickness

6 = emiss iv i ty

p = density of m a t e r i a l

p' = local a i r density

p = viscosi ty

plo = viscosi ty a t to ta l t empe ra tu r e

ci = dimensionless fac tor accounting fo r density and viscosi ty in boundary l aye r

= t ime

S t ruc tures and Design

A = forebody o r dece l e r a to r r e f e r ence a r e a

A = su r f ace a r e a of dece l e r a to r f

A p = payload re fe rence a r e a

AD = dece le ra to r r e f e r ence a r e a

c = factor re la ted to chute suspension l ine confluence angle

CD = drag coefficient

(CDA)T = total d r ag a r e a of forebody and dece l e r a to r

D = dece l e r a to r d i ame te r

Dp = parachute inflated d i ame te r

d = forebody d i ame te r

e = fac tor re la ted to the s t reng th l o s s f r o m ab ra s ion


E = modulus of e las t ic i ty

Fo = peak dece le ra to r design load

f - design s t r e s s f -

h = number of mer id i an webs

J = safety fac tor

K = react ing load distr ibution fac tor

Kc(Km) = meridian cable o r web strength-to-weight ra t io

K = dece l e r a to r envelope fabr ic s t rength- to-weight f

r a t io

2 K = shape p a r a m e t e r

k = fac tor re la ted to s t reng th loss f r o m fat igue

L = length of each mer id ian

LS = chute suspension l ine 1,ength

I! Q~ = she l l length in mer id i an di rect ion

m = nose -cap m a s s P

m = m a s s of r ing R

mSH = m a s s of she l l

N = mer id i an she l l r esu l tan t d No = N evaluated a t R = R m b

o = f ac to r re la ted to s t reng th due to s t reng th loss in m a t e r i a l f r o m wa te r and wa te r vapor absorpt ion

P = p r e s s u r e

A P R = p r e s s u r e di f ferent ia l a c r o s s dece le ra to r envelope f ab r i c


PT = total p r e s s u r e

p = p r e s s u r e acting on the shel l

q = dynamic p r e s s u r e

R = dece l e r a to r radius

Rb = she l l radius a t the ba se

RT = rad ia l d is tance to point of tangency of nose cap and she l l

T = mer id i an design tension load

t = thickness

u = fac tor f o r s t r eng th a t connecting points

W = weight

W (W ) = dece l e r a to r weight B D

W = dece le ra to r fabr ic coating weight C

W - dece l e r a to r f ab r i c weight f -

W = dece l e r a to r mer id i an weight m

WT = total weight of forebody and dece l e r a to r

W p = payload (forebody) weight

Z = number of chute suspension l ines

D. F. = to ta l fabr ic des ign fac tor , the product of safe ty fac tor , dynamic loading, s e a m efficiency, t empe ra tu r e , e t c .

D. F. ' = median design fac tor

erf (K) = e r r o r function

C. F. = unit coating weight


= angle between axis and tangent to sur face

h = chute geometr ic porosi ty

p I m a t e r i a l density

p ' = applied load distr ibution factor

c = allowable s t r e s s a

$ = angle between flow and no rma l to sur face

LIST O F REFERENCES

Chernowitz, G. ; and DeWeese, J. H. : P e r f o r m a n c e of and Design C r i - t e r i a f o r Deployable Aerodynamic Dece l e r a to r s . Second m a j o r revision of the USAF parachute handbook, ASD-TR-61-579, AD-429971, Decem- b e r 1963.

F o s t e r , A. D. : A Compilation of Longitudinal Aerodynamic Cha rac t e r - i s t ics Including P r e s s u r e Informat ion fo r Sha rp and Blunt- Nose Having F l a t and Modified Bases . Sandia Corporation, s C - ~ - 6 4 - 13 11, January 1965.

Nichols, J. 0. 4 and Nierengar ten, E . A. : Aerodynamic Cha rac t e r i s t i c s of Blunt Bodies. JPL-TR-32-677 , N- 116-287, November 1964.

Penland, J. A. : A Study of the Stability and Location of the Center of P r e s s u r e on Sharp, Right Ci rcu la r Cones a t speeds , N'T~-A TN D-2283, May 1964.

Penland, J. A. : Aerodynamic F o r c e Cha rac t e r i s t i c s of a Se r i e s of L i f t . ing Cone and Cone- Cylinder Configurations a t a Mach Number of 6 . 83 and - Angles of Attack Up to 130 Degrees . NASA 'TN D-840, ~ u n e m l ,

Aerodynamic Cha rac t e r i s t i c s of Spher ical ly Blunted Cones a t Mach Num- - b e r s f r o m 0. 5 to 5. 0. George C. Marsha l l Space Flight Cente r , MTP- Aero-61-38, May 1961.

Maas , W. L. : Exper imenta l Determinat ion of Pitching Moment and Damping Coefficients of a Cone i n Low Density, Hypersonic Flow. Uni- -- ve r s i t y of California, 1nsTtute of Engineering Resea rch , TR HE- 150- 190, Se r i e s 20, Issue No. 135, AD-266787, October 1961.

North Amer i can Aviation, Miss i le Division: Exte rna l Drag Manual. - NAA/MD 59-453, 1960, p 5 . ~ 0 .

Rainey, R. W. : Working Char t s fo r Rapid Predic t ion of F o r c e and P r e s s u r e Coefficients on A r b i t r a r y Bodies of Revolution by Use of New- tonian Concepts. NASA TN D- 176, December 1959.

Hoerner , S. F. : Fluid-Dynamic Drag. Published by author , 1958.

Tobak, Ma ; and Wehrend, W. R. : Stability Derivatives of Cones a t Su- .--a --

person ic Speeds, NACA TN 3788, September 1956.


LIST O F REFERENCES GER-12616

12. Gendtner, W. J. : Sha rp and Blunted Cone F o r c e Coefficients and Cen-. t e r s of P r e s s u r e f r o m Wind Tunnel T e s t s a t Mach Numbers f r o m 0. 50 to 4 .06. Convair Report ZA-7-017, June 1955.

13. Young, G . B. W. ; and Siska, C. P. : "Supersonic Flow Around Cones al; L a r g e Yaw. '' Journa l of Aeronaut ical Sciences , Vol 19, p 11 1 , 1952.

14. Stone, A. H. : "On Supersonic Flow P a s t a Slightly Yawing Cone. " -- Jour - nal of Mathematics and Phys ics , Vo1 30, 1952.

15. Van Dyke, M. D. : A Study of Second O r d e r Supersonic Flow Theory. NACA Report 1081 ( fo rmer ly NACA TN 220), 1952.

16. F e r r i , A. : Supersonic Flow Around C i r cu l a r Cones a t Angles of Attack. NACA Report No. 1045, 1951.

17. Van Dyke, M. D. : " F i r s t - O r d e r and Second-Order Theory of Supersonic Flow P a s t Bodies of Revolution. " Journa l of Aeronaut ical Sciences , Vo: 18, March 1951.

18. Staff of the Computing Section, Cente r of Analysis (under di rect ion of Zdenek Kopal): Tables of Supersonic Flow Around Cones a t La rge Yaw. Technical Report No. 5, Massachuse t t s Inst i tute of Technology, 1949.

19. Rantzsche, W. ; and Wendt, H. : Cones in Supersonic Flow. RAND '7-8, January 1948.

20. Stone, A. H. : "On Supersonic Flow P a s t a Slightly Yawing Cone. " Jour - nal of Mathemat ics and Phys ics , Vol 27, 1948.

21. Staff of the Computing Section, Cente r of Analysis (under di rect ion of Zdenek Kopal): Tables of Supersonic Flow Around Yawing Cones, Tech- nical Report No. 3 , Massachuse t t s Inst i tute of Technology, 1947.

22. Staff of Computing Section, Center of Analysis (under di rect ion of Zdenek Kopal): Tables of Supersonic Flow Around Cones. Technical Report No. 1 , Massachuse t t s Inst i tute of Technology, 1947.

23. Heinr ich, H. G . ; Hess , R. S. ; and S tumbr i s , G . : Drag Cha rac t e r i s t i c s of P la tes . Cones. and S ~ h e r e s i n the Wake of a Cvlindrical Bodv a t T r a n - sonic speeds . R ' T D - T D R - ~ ~ - ~ o ~ ~ , AD-457055, a n d ~ 6 5 - 13636, January 1965.

24. Heinrich, H. G . ; and Hess , R . S. : Drag Cha rac t e r i s t i c s of P la tes , Cones , Spheres,and Hemispheres in the Wake of a F0rebod.y a t Transonic and Supersonic Speeds. RTD-TDR-63-4242, December 1964.

25. Heinrich, H. G. ; and Hess , R. S. : Drag Cha rac t e r i s t i c s of Severa l Twc- - Body Sys tems a t Transonic and Supersonic Speeds. RTD-TDR-63-4226, December 1964.

- 2 0 0 -

LIST O F REFERENCES GER- 12616

26 . Charczenko, N. : Aerodynamic Cha rac t e r i s t i c s of Towed Spheres , Coni- ca l Rings, and Cones Used a s Decc lc ra to rs a t Mach Numbers f r o m 1. 57- to 4.65. NASA TN D-1789, N63-15308, Apr i l 1963.

27. Alexander. W. C. : Investigation to Determine the Feasibi l i tv of Using. V cl.

Inflatable Ralloorz- Tvae D r a ~ Devices for Recoverv A ~ ~ l i c a t i o n s in the Transonic , Supersonic and Hypersonic Fllght Regime. P a r t 11, Mach 4 to Mach 10 Feasibi l i ty Lnvestigation, ASD- TDR- 62-702, December 1962.

Charczenko, N. ; and McShera, J'. T . , J'r. : Aerodynamic Cha rac t e r i s - t i c s of Towed Cones Used a s Dece le ra to rs a t Mach Numbers f r o m 1. 57 to 4.65. NASA TN D-994, December 1961,

Wegener, P. P. ; and Ashkenas , H. : Wind Tunnel Measurements of Sphere Drag a t Supersonic Speeds and Low Reynolds Numbers . JPL- TR-34-160, N63.-18848, June 1961.

Masson. D. J. : M e a s u r e n ~ e n t s of Sphere Drag f r o m Hvaersonic Con- " I L - tinuum to F r e e - Molecule Flow. Rand Report RM2678, November 196 0.

Hodges, A. J . : "The Drag Coefficient of Very High Velocity Spheres . I !

Journal of Aeronaut ical Sciences , Vol 24, 1957.

May, A. ; and Witt, W . R . , J r . : F r e e Flight Determinations of the Dra) ; Coefficient of Spheres . NAVORD Report 2352, August 1952.

Van Dyke, M. D. ; Young, G . W. ; and Slsha, C . : " P r o p e r Use of the M,T Tables f o r Supersonic Flow P a s t Inclined Cones. !' Journa l of Aeronaut i - ca l Sciences , Vol 18, 1951.

Cha r t e r s , A. C, ; and Thomas , R . N. : "The Aerodynamic Pe r fo rmance of Smal l Spheres f r o m Subsonic to High Supersonic Velocit ies. " Journa of Aeronaut ical Sciences , Vol 1 2 , 1945.

McShera, J. .T. , J r . : Aerodynamic D r a g a n d Stability Charac te r i s t i cs of Towed Inflatable Dece le ra to rs a t S u ~ e r s o n l c speeds . NASA TN D-

L-

1601, March 1963.

36. Nebiker, F . R. and Karaffa, N. T, : Feasibility Study -- of an Inflatable T v ~ e Stabilization and Decelera t ion Svs tem fo r Hieh-Altitude and Hleh

Lp- _^_Y_

speed Recovery. W D - , T R - ~ O - 182, November 1 96ul.

37. McShera, J . T . ; and Keyes, J . W. : Wlnd Tunnel Investigation of a-p" a Bal- loon a s a Towed Dece le ra to r a t ~ a c h m u m b e r s f r o m 1. 47 to 2 , 50 . NASA

38. Uselton, J. C. ; and Hahn, J . S. : - D r x C h a r a c t e i - i s t i c s -- of T h r e e Ballutc


Dece l e r a to r s i n the Wake of the ALARR Payload a t Mach Numbers 2 to 4. AEDC-TR-65-2 18, Arnold Engineering Development Cente r , October 1965.

Unpublished data of t e s t s a t AEDC wind tunnel, August 1965.

Deitr ing, J. S. ; and Hil l iard , E . E . : Wind. Tunnel Investigation of Flex- ib le Aerodynamic Dece le ra to r Charac te r i s t i cs a t Mach Numbers 1. 5 to (?. AEDC-TR-65-110, June 1965.

Unpublished AEDC Ballute wind tunnel t e s t s conducted December 1964.

Unpublished Holloman AFB Ballute s led t e s t conducted November 1964.

GER- 11665S3: Aerodynamic Deployable Dece le ra to r Pe r fo rmance Evalc,- at ion P r o g r a m . Flight T e s t Repor t (TB-21, FDL/RTD/USAF, ~ e b r u a r j - .iwK--- GER- 11665SZ: Aerodynamic Dep1.oyable Dece le ra to r Pe r fo rmance Evalu- at ion P r o g r a m . Flight Tes t Report (TB - 1 B), FDL/RTD/USAF, Februa-ry 1965.

GER- 11665S1: Aerodynamic Deployable Dece le ra to r P e r f o ~ m a n c e Evalu- at ion P r o g r a m . Flight T e s t Report (TB- lA),FDL/RTD/USAF, F e b r u a r y 1965.

Knapp, H. : Gemini Ballute S t ruc tura l T e s t a t Mach Numbers 0. 55 and 1. 92, A E D C - T D R - ~ ~ - 131, June 1964.

Unpublished data of t e s t s a t AEDC wind tunnel, Apr i l 1964.

Bell , D. R . : P r e s s u r e Measurements on the Rigid Model of a Balloon Dece le ra to r in the Wake of a Simulated Miss i le Payload a t Mach Num- b e r s 1. 5 to 6 . A E D C - T D R - ~ ~ - ~ ~ , Apr i l 1964.

GER- 11 538 (Altgelt, R. ): Gemini Ballute Sys tem Development - Final Report . January 1965.

Deitering, J. S. : P e r f o r m a n c e of Flexible Aerodynamic Dece le ra to rs a t Mach Numbers f r o m 1. 5 to 6. A E D C - T D R - ~ ~ - 119, July 1963.

Ashby, G . C. ; and Ca ry , A. M. : A P a r a m e t r i c Study of the Aerodynamic Cha rac t e r i s t i c s of Nose-Cyl inder -F la re Bodies a t a Mach Number of 6. 0. NASA T N D-2854, June 1965.

Champney, W. B. ; Athans, J. B. ; and Mayerson, C. D. : A Study of Hy- personic Aerodynamic Drag Devices. WADC-TR- 59-324, December 19b0.

LIST O F R E F E R E N C E S GER-12616

Deep, R. A . ; a n d Henderson , J . H. : Studv of Aeroclvnamic C h a r a c t e r - & .

i s t i c s of Cone- C y l indar - Conica l -- ??rusturn Bod ies by L i n e a r i z e d T h e o r y of Super son ic Flow. Ordnance M i s s i l e L a b o r a t o r y , R e p o r t 6 R 2 P , J ~ n e 1955.

Nickel , W. E. ; a n d S l m s , L , W . : - S t u d ~ o f a n E x p l o r a t o r y F r e e - F l ight Lnves t iga t ion of Deployable A e r o d y n a m i c D e c e l e r a t i o n s Opera t ing a t High Al t i tudes and a t Hlgh Mach N u m b e r s , FDL-TDR-64-35 , Vol 1 , Ju ly 19tT4-

Lowry , J. F, : -- A e r o d y n a m i c C h a r a c t e r i s t i c s of Var ious Types of Fu l l S c a l e P a r a c h u t e s a t Mach N u m b e r s f r o m 1. 8 to 3 , 0. AEDC-TDR-64- 120, June 1964.

P e t e r s e n , P. E . : Study of P a r a c h u t e P e r f o r m a n c e and Des ign P a r a m e - - t e r s f o r High Dynamic P r e s s u r e Operation. FDL- T D R - 6 4 - 6 6 , May 196.1, --

Dei te r ing , J. S . : Wind Tunnel Inves t iga t ion of F lex ib le P a r a c h u t e Model -- C h a r a c t e r i s t i c s a t Mach N u m b e r s 1 , 5 t o 5, AEDC.- 'TDR-63-263, J ' a n u a ~ , y 1964.

De i t e r ing , S. S. : P e r f o r m a n c e of F lex ib le P a r a c h u t e Models a t Mach - N u m b e r s f r o m 1 . 5 to 4. A E - D C - T D R - ~ ~ - , ~ ~ ~ , D e c e m b e r 1962.

Maynard , J . D. : A e r o d y n a m i c - Cha . rac tc r l s t i c s of P a r a c h u t e s at Mach --- N u m b e r s f r o m 1 . 6 t o 3 . NASA TN D-752, May 1961.

Johnson, C. T . : Inves t iga t ion of t h e C h a r a c t e r i s t i c s of 6 - F o o t Drogue Stabi l iza t ion Ribbon P a r a c h u t e s a t High Al t i tudes and Low Superson ic Speeds . NASA TM X-448, November 1960.

Nichols , J. H. : Wind Tunne l Invest ight lon of S tabi l iza t ion P a r a c h u t e s -- f o r the B- 58 C r e w E s c a p e Capsu le , AEDC- TN-59-107, S e p t e m b e r 1959 --- Reichenau, D. E . A. : Aerodynawnc P e r f o r m a n c e of Var ious Hyperf lo - ---- -- and Hemis f lo P a r a c h u t e s a t Mach N u m b e r s f i-om 1 . 8 to 3 . 0. AEDC- TR 65-57 , M a r c h 1965.

S i m s , L . W. : Analy t i ca l a n d Exper ' lmenta l Inves t iga t ion of Super son ic ------- --- -- P a r a c h u t e p h e n o m e n a , ASD- TDR-62-844, Chicago, i l l . , Cook Tech- nologica l C e n t e r , F e b r u a r y 1 963 (CONFLDENT'IAL].

De i t e r ing , J. S . : Inves t iga t ion of F l e x i b l e P a r a c h u t e Model C h a r a c t e r - -- i s t i c s a t Mach N u m b e r s 1 . 5 to 6 . AXD-CI~~;DR-~~ 185, X63-13449, Oc- t obe r 1962.

Guy, L . D . : " T e n s i o n She l l S t ~ u c t u r e s for Low Densi ty E n t r y T'ehicles. ' P r e s e n t e d a t A U Second Annual Meet ing , J u l y 1965.


66. Anderson, M. S. ; Robinson, J. C. ; Bush, H. G . ; and F re l i ch , R. W. : A Tension Shell S t ruc ture fo r Application to En t ry Vehicles. NASA TN D-2675.

67. 'Unpublished towed tension she l l wind tunnel data behind X- 15 model conducted March 1965.

68. Study of a Drag Brake Satell i te Recovery System. AVCO-Everett Re- s e a r c h Labora tory , ASD-TR-61-348, Vol 1, 2, 3, and 4, January 1962.

69. B a e r , A. L. ; Lindsey, E. E . ; and Rippey, J. 0. : P r e s s u r e Distr ibution T e s t s on Five AVCO Modulated Drag Brake Configurations a t supersonic- and Hypersonic Speeds. AEDC-TN-61-4, F e b r u a r y 1961.

70. MacNeal, R. H. : Mechanics of a Coned Rotating Net. A s t r o Resea rch Corporat ion, Repor t No. ARC-R- 177, F e b r u a r y 1965.

71. Kyser , A. C . : The Rotornet , a High-Per formance Hypersonic Dece le r - a t o r f o r P lane ta ry Ent ry . A s t r o Resea rch Corporation, Report No. ARC- R- 176, F e b r u a r y 1965.

72. Knacke, T . W. ; Paulson, K. R. ; and Schu r r , G. G . : Study of Soft Re- coverv. Technical Report AFOSR- 104, N62- 13 153, March 1961.

73. Reichenau, D. E . A. : Investigation of Various Full-Scale Parachutes a t Mach Number 3 . 0 . AEDC-TR-65-241, December 1965.

74. Wehrend, W. R. : An Exper imenta l Evaluation of Aerodynamic Damping Moments of Cones with Different Cente rs of Rotation. NASA T N D- 1768, March 1963.

75. Mayo, E . E. ; Lamb, R. H. ; and Romere , P. 0. : Newtonian Aerody- namics fo r Blunted Raked-off Ci rcu la r Cones and Raked-off Ell ipt ical Cones. NASA TN D-2624, Mav 1965.

76. Lichtenstein, J. H. ; F i s h e r , L . R. ; She r , S. H. ; and Lawrence , G . F. : Some Static, Osci l la tory , and F ~ e e - Body Tes t s of Blunt Bodies of Revo- lution at Low Subsonic Speeds. NASA Memo 2-22- 59L, Apr i l 1959.

77. Mar te , J, E. ; and Weaver , R. W , : Low Subsonic Dynamic Stability In- vestigation of Severa l P lane ta ry Ent ry Configurations in a Ver t ical Wind Tunnel ( P a r t 1) . J e t Propuls ion Labora tory , Technical Repor t No. 32- 743, May 1965.

78. Schlichfing, H. : Boundary Layer Theory, t r ans la ted by J. Kesten. McGraw Hill, New York, N. Y. , 1955.


79. S ims , L. W. : 'The Effects of Design P a r a m e t e r s and Local Flow Flelds on the Pe r fo rmance of Hyperflo Supersonic Parachutes and High Dynamic - P r e s s u r e Parachute Concepts. AFFDL-TR-65- 150, Vol 1 , September

80, C;ER 1 L687: Wakes, The i r S t ruc ture and Influence Upon A e r o d y r k x n i ~ .- -- Decele ra to rs . Akron. Ohio. Goodvear Aerospace Corporat ion, May 1966.

8 1. C rawford, D. M. : Investigation of the Flow Over a Spiked Nose Hemis - phere Cylinder a t a - ~ a c h Number of 6 .8 . NASA T N D- 118, ~ e c e m b e r 1959.

82, Nebiker, F . R . : Aerodynamic Deployable Dece le ra to r Pe r fo rmance Evaluation P r o g r a m . AFFDL-TR-65-27 , May 1965.

- -

83. GER- 11820 ( N e r e m , R. M. ) : Supersonic Wake Phenomena with Applica tion to Ballute- Tvpe Dece le ra to rs . November 1964.

84. GER- 11824 (Ne rem, R . M. ): An Approximate Method fo r Including the Effect of the Inviscid Wake on the P r e s s u r e Distr ibution on a Ballute- a p e Dece le ra to r . November 1964.

85, Zeiberg, S . L. : "Trans i t ion Cor re la t ion fo r Hypersonic Wakes, " A , U Journal , Vol 2, No. 3 , March 1964, 564, 565.

86. Candidate Mate r ia l s fo r High- Tempera tu r e Fab r i c s . WADC- T R - 59- 155, September 1959.

87. Anderson, A. R. : Effect of Biological Ster i l iza t ion and Vacuum on C e r - tain Parachute Retardat ion Sys t em Components. J e t Propuls ion Labora- tory , Final Report No. 4324, August 1963.

88. Kaswell, E . R. : Wellington Sea r Handbook of Industr ia l Text i les , 1963.

89. Symposium on F ibrous Mater ia l s . ASD- T D R - ~ ~ - 964, January 1963.

90. Metal F i laments fo r High-Tempera ture F a b r i c s . ASD-TR-62- 180, Feb-. r ua ry 1962.

91. Charac te r iza t ion of Graphi te and Carbon- Based Fibrous Mater ia l s Ex- posed to Varvine: Environments . A F M L - T R - ~ ~ - ~ ~ , June 1965.

92. A i r F o r c e Mater ia l s Symposium. AFML- TR.-65-29, June 1965.

93. , New - and Improved Mater ia l s fo r Expandable S t ruc tures - P a r t 1 . ASD- TDR-62-542, June 1962.

94. Flexible F ibrous S t ruc tu r a l Mate r ia l s . AFML-TR-65- 118, Apr i l 1965,

APPENDIX A GER-12616

I - NASA R E P O R T S

MacNea l , R . H. : Mechan ics of a Coned Rcta t ing Nct. NASA CR-248, Ju ly 1965. - .

Kyan, A. C. : T h e Rotonet: A H i g h - P e r f o r m a n c e Hyperson ic D e c e l e r a t o r f o r P l a n e t a r y ~ n t r y . NASA CR-247,

Af terbody P r e s s u r e s on Boa t - t a i l ed Bodies of Revolut ion Having T u r b u l e n t Boundary L a y e r s a t M a c h 6 . NASA TN D-2761

Study of the Stabi l iza t ion and D r a g a t M a c h N u m b e r s f r o m 4. 5 to 13. 5 of a Conica l Venus E n t r y Body. NASA T N D-2877.

S m e t a n a , F. 0. : Inves t iga t ions of the P e r m e a b i l i t y of P a r a c h u t e F a b r i c s . N65-15016, N A S A - - C R - ~ O ~ ~ ~ ,

McShera , J. T . , Jr. : T h e U s e of a S u p e r s o n i c Wind Tunnel a s a Means of Inves t iga t ing ~ e c e l e r a t o r Configurat ion. X65- 10857, NASA- TM-X- 54543

Charczenko , N. : Wind Tunnel Inves t iga t ion of D r a g and Stabi l i ty of P a r a c h u t e s at Super son ic Speeds . NASA- TM-X- 991, August 1964

Rakich , J. V. : N u m e r i c a l Calcula t ion of S u p e r s o n i c Flows of a P e r f e c t Gas O v e r Bodies of Revolut ion a t S m a l l Angles of Yaw. NASA TN-D-2390, July 1954

B e r t r a m , M. H. : C o r r e l a t i o n G r a p h s f o r Super son ic Flow a round Right C i r c u - l a r Cones a t Z e r o Yaw in A i r a s a P e r f e c t G a s . NASA T N D-2339, June 1964

A r r i n g t o n , J. P.' and Maddalon, D. V. : A e r o d y n a m i c C h a r a c t e r i s t i c s of Sev- e r a l Li l t ing and Nonlifting Conf igura t ions a t Hyperson ic Speeds i n A i r and H e l i u m (U). NAS.A TM-X- 918, June 1964 ( C O N F I D E N T U L )

Pen land , J. A . : A Study of the Stabi l i ty a n d Locat ion of the C e n t e r of P r e s - s u r e on S h a r p , Right C i r c u l a r Cones a t Hyperson ic Speeds . NASA T N D-2283, May 1964

Yoshikawa, K. K. and Wick, B . H. : A e r o d y n a m i c and Rocket Brak ing of Blunt Non-lifting Vehic les E n t e r i n g the E a r t h ' s A t m o s p h e r e a t V e r y High Spe,.?;-ls, NASA TN D-2239, A p r i l 1964

B u r k , S. M . , J r . : Low-Sp-ed F r e e - F l i g h t S tabi l i ty and D r a g C h a r a c t e r i s t i c s of Rad ia l ly Vented P a r a c h u t e s . NASA TN D-2271, M a r c h 1964

APPENDIX A G E R - 12616

H a r r i s , J. E . : A B a s i c Study of Spher i ca l ly Blunted Cones Including F o r c e and Moment Coeff ic ient C o r r e l a t i o n and A i r - He l ium Simula t ion S tud ies , (M. S. , T h e s i s ) , NASA CR-56254, X65- 12565, M a r c h 1964

Keyes , J. W. : Longi tudinal A e r o d y n a m i c C h a r a c t e r i s t i c s of Blunted Cones a t Mach N u m b e r s of 3 . 5 , 4 . 2 and 6 . 0 . NASA T N D-2201, F e b r u a r y 1964

Nichols , J. and N i e r e n g a r t e n , E. : Sta t i c A e r o d y n a m i c C h a r a c t e r i s t i c s of Blunted Cones and Round-Shouldered Cy l inde r s Sui table f o r P l a n e t a r y E n t r y Veh ic le s a t a Mach N u m b e r Range 1 . 6 5 to 9. 00. NASA CR-58666, N64-29212, F e b r u a r y 1964

Smeda l , 14. A . , Capt . USN(MC), and C r e e r , B. Y. : Phys io log ica l Ef fec t s of A c c e l e r a t i o n O b s e r v e d dur ing a Cent r i fuge Study of P i l o t P e r f o r m a n c e , NASA TN D-345, D e c e m b e r 1963

B a r t o n , R . L . and Ki lgore , R . A. : T h e Aerodynamic Damping and O s c i l l a t o r y Stabi l i ty i n P i t c h of Two High-Drag Bodies of Revolut ion a t T r a l s o n i c Speeds . NASA T M X- 906, X64- 10091, November 1963

Wehrend , W. R . , Jr . : A. Wind Tunne l Inves t iga t ion of the Effec t of Changes in R a s e Contour on the Damping i n P i t c h of Blunted Cone. NASA TN D-2062, Novembe r 1 963

B r o o k s , C. W. , Jr . and T r e s c o t , C. D. , Jr . : T r a n s o n i c Inves t iga t ions of the Effec ts of Nose B lun tness , F i n e n e s s Rat io , Cone Angle, and B a s e Shape on the S ta t i c Aerodynamic C h a r a c t e r i s t i c s of S h o r t , Blunt Cones a t Ang les of At t ack to 180 D e g r e e s . NASA T N D-1926, August 1963

T e r r y , J. E. and M i l l e r , R. J. : A e r o d y n a m i c C h a r a c t e r i s t i c s of a T r u n c a t e d - Cone Lif t ing R e - e n t r y Body a t M a c h N u m b e r s f r o m 10 to 21. NASA T M X-786, August 1963 (CONFIDENTIAL)

Chapman , G. T . and J a c k s o n , C. T . , Jr . : M e a s u r e m e n t of Heat T r a n s f e r to Bodies of Revolut ion i n F r e e F l igh t by U s e of a C a t c h e r C a l o r i m e t e r . NASA T N D- 1890, Ju ly 1963

Chapman, A. J. : A n E x p e r i m e n t a l Evaluat ion of T h r e e Types of T h e r m a l P r o t e c t i o n M a t e r i a l s a t M o d e r a t e Heat ing R a t e s and High T o t a l Heat Loads . NASA T N D-1814, Ju ly 1963

Schippel l , H. R. : T r a i l b l a z e r I R e - e n t r y - B o d y Wind-Tunnel T e s t s a t a Mach N u m b e r of 6 . 7 wi th T h e o r e t i c a l A e r o d y n a m i c s and a L i m i t e d Dynamic Analy- s i s . NASA TN D-1936, J u l y 1963

McShera , J. T . , J r . and W a s s u m , D. L . : Stabi l i ty and Con t ro l C h a r a c t e r i s - t i c s of a Low-Li f t -Drag-Ra t io R e - e n t r y Vehic le a t Mach N u m b e r s f r o m 2. 3 0 . to 4 .65 . NASA T M X-891, J u l y 1963, (CONFIDENTIAL)


Reid, R. and Middleton, D. B. : A T r a j e c t o r y Analys is of a Var iab le -Drag Payload E jec ted f r o m a Vehicle i n a Low E a r t h Orbi t . NASA TN D-1938, July 1963

Shaw, D. S . ; Fu l l e r , D. E . ; and Babb, C . D . : Effects of Nose Bluntness , F ineness Rat io , Cone Angle, and Model Base on the Stat ic Aerodynamic Cha rac t e r i s t i c s of Blunt Bodies a t Mach Numbers of 1. 57, 1 . 8 0 and 2. 16 and Angles of Attack up to. 160 Degrees . NASA TN D- 1781, May 1963

Charczenko, N. : Aerodynamic Cha rac t e r i s t i c s of Towed Sphe re s , Conical Rings, and Cones Used a s Dece l e r a to r s a t Mach Numbers f r o m 1. 57 to 4.65. NASA TN D- 1789, N63- 15308, Apri.1 1963

McShera , J. T. , Jr. : Aerodynamic Drag and Stabil i ty Cha rac t e r i s t i c s of Towed Inflatable Dece l e r a to r s a t Supersonic Speeds. NASA TN D- 1601, March 1963

Wehrend, W. R . , Jr. : An Exper imenta l Evaluation of Aerodynamic Damping Moments of Cones with Different Cen t e r s of Rotation. NASA TN D- 1768, March 1963

Grimwood, J. M. : P r o j e c t M e r c u r y - A Chronology. NASA SP-4001, 1963

Fu l l e r , D. E. and Babb, 0. D. : Stat ic Stabil i ty Investigation of P roposed P ro j ec t F i r e Space-Vehicle and Re-en t ry -Package Configurations a t Mach Numbers f r o m 1.47 to 4.63. NASA N63- 10178, NASA TN D- 1497, November 1962

Tobak, M. : Analytical Study of the Tumbling Motions of Vehicles Enter ing P l ane t a ry A tmosphe re s . NASA TN D- 1549, October 1962

Col t rane , L. C. : Stabil i ty Investigation of a Blunted Cone and a Blunted Ogive with a F l a r e d Cyl inder Afterbody a t Mach Numbers f r o m 0 .30 to 2 .85. NASA TN D- 1506, October 1962 (Supersedes NASA TM X- 199)

G a m s e , B. and Yaggy, P. F. : Wind Tunnel Tes t s of a S e r i e s of 18-Foot- Diamete r Pa r achu t e s wi th Extendable F laps . NASA T N D- 1334, August 1962

Sanger , M. B. , J r . : Drag Cha rac t e r i s t i c s and Dynamic Stabil i ty i n Descent of a Rota ry Parachu te Tes t ed in a Ver t i ca l Tunnel. NASA TN D-1388, August 1962

Seiff, A. : Secondary Flow F ie lds Embedded in Hypersonic Shock L a y e r s . TN D- 1304, NASA, May 1962

Pe t e r son , V. L. : Motions of a Shor t 10 Degree Blunted Cone Enter ing a Mar - t ian Atmosphere a t A r b i t r a r y Angles of At tack and A r b i t r a r y Pitching Rates . NASA TN D-1326, May 1962

APPENDIX A GER- 12616

Hillje, E. R. and P e a r s o n , A. 0. : Transonic Stat ic and Dynamic Longitudinal Stability Cha rac t e r i s t i c s of a Low-Fineness-Rat io , Blunted-Cylinder Re-en t ry Body having a Converging-Cone Afterbody. NASA T M X-672, X62- 10101, May 1962 (CONFIDENTIAL)

Lazzeron i , F. A. : Exper imenta l Investigation of a Disk-Shaped Re-en t ry Con- f iguration a t Transonic and Low Supersonic Speeds. NASA T M X-652, X62- 10098, May 1962 (CONFIDENTIAL)

Hillje, E. R. and Kilgore, R. A. : Transonic Dynamic Longitudinal Stability Cha rac t e r i s t i c s of Six Bal l is t ic Re- en t ry Configurations Designed fo r Super- sonic Impact . NASA TM X- 673, X62- 1002 1, March 1962 (CONFIDENTIAL)

Holtzclaw, R. W. : Static Stabil i ty and Control Charac te r i s t i cs of a Half-Cone Entry Configuration a t Mach Numbers f r o m 2 .2 to 0. 7. NASA TM X-649, March 1962

Penland, J. A. : A Study of the Aerodynamic Cha rac t e r i s t i c s of a Fixed Geom- e t r y Pa rag l i de r Configuration and Three Canopies with Simulated Variable Canopy Inflation a t a Mach Number of 6 .6 . NASA TN D- 1022, March 1962

Hillje, E . R. and Kilgore, R. A. : Transonic Dynamic Longitudinal Stability Cha rac t e r i s t i c s of Six Ball ist ic Re-en t ry Configurations Designed fo r Super - sonic Impact. X62- 10021, NASA T M X-673, March 1962 (CONFIDENTLAL)

Thompson, R. F. and Jones , E. M. : Recovery Operations. N62- 10236, Feb- rua ry 1962

Thompson, R. F. and Cheatham, D. C. : Considerat ions fo r Spacecraf t Re- covery f r o m Lunar Miss ions . N-107-051, January 1962

Wells , W. R. and Arms t rong , W. 0. : Tables of Aerodynamic Coefficients Obtained f r o m Developed Newtonian Express ions fo r Complete and P a r t i a l Conic and Spher ic Bodies a t Combined Angles of Attack and Sidesl ip with Some Comparisons with Hypersonic Exper imenta l Data. NASA TR R- 127, 1962

Goodwin, G. and Howe, J. T. : Recent Developments in Mass , Momentum, and Energy T r a n s f e r a t Hypervelocit ies. NASA Univers i ty Conference on the Sci- ence and Technology of Space Exploration, NASA SP- 11, Vol 2 , 1962, pp 291- 301

Treon , S. L. : Stat ic Aerodynamic Cha rac t e r i s t i c s of Shor t Blunt Cones with Various Nose and Base Cone Angles a t Mach Numbers f r o m 0 . 6 to 5 . 5 and Angles of Attack to 180 Degrees . NASA TN D-1327, 1962

Smith, W. G. and Pe t e r son , W. P. : Free -F l igh t Measurements of Drag and Stabil i ty of a Blunt- Nosed Cylinder with a F l a r e d Afterbody in A i r and Carbon Dioxide. NASA TM X-642, December 1961


S t ivers , L. S. , J r . and Levy, L. L , J r . : Longitudinal F o r c e and Moment Data a t Mach Numbers f r o m 0 .60 to 1. 40 fo r a Fami ly of Ell ipt ic Cones with Various Semi-apex Angles. NASA TN D- 1149, December 1961

Charczenko, N. and McShera, J. T . , J r . : Aerodynamic Cha rac t e r i s t i c s of Towed Cones Used a s Dece le ra to rs a t Mach Numbers f r o m 1. 57 to 4.65. NASA TN D-994, December 1961

Dickey, R. R. : F o r c e s and Moments on Sphere- Cone Bodies in Newtonian Flow. NASA TN D- 1203, December 1961

McShera, J. T. and Keyes, J. W. : Wind Tunnel Investigation of a Balloon a s a Towed Decelera tor a t Mach Number f r o m 1 .47 to 2.50. NASA TN D-919, N62-71493, August 1961

Penland, J. A. : Aerodynamic F o r c e Charac te r i s t i cs of a Se r i e s of Lifting Cone and Cone-Cylinder Configurations a t a Mach Number of 6 .83 and Angles of A t t a c k u p to 130 Degrees . NASA TN D-840, June 1961

Henderson, A. J r . and Braswel l , D. 0. : Char t s f o r Conical and Two-Dimen- s ional Oblique-Shock Flow P a r a m e t e r s in Hel ium a t Mach Numbers f r o m about 1 to 100. NASA TN D-819, June 1961

Aerodynamic Charac te r i s t i cs of Spher ical ly Blunted Cones a t Mach Numbers f r o m 0. 5 to 5. 0. George C. Marsha l l Flight Center , Report MTP-AERO- 61-38, May 1961

Maynard, J. D. : Aerodynamic Charac tc r i s t i cs of Parachutes a t Mach Num- b e r s f r o m 1 . 6 to 3. NASA TN D- 752, May 1961

C r i e r , N. T . and Sands, N. : Reg ime of F r o z e n Boundary Laye r s in Stagna- tion Region of Blunt Re-en t ry Bodies. NASA TN D-865, May 1961

McDearmon, R. W. and Lawson, W. A. : Investigation of the Norma l -Fo rce , Axial- F o r c e , and Pitching Moment Cha rac t e r i s t i c s of Blunt Low- F ineness - Ratio Bodies of Revolution a t a Mach Number of 3. 55. NASA T M X-467, N63- 13911, Apr i l 1961

Czarnecki , K. R. and Jackson, M. W. : Effects of Cone Angle, Mach Number , and Nose Blunting on Transi t ion a t Supersonic Speeds. NASA TN D-634, Janu- a r y 1961

Stoney, W. E. , Jr. : Collection of Ze ro - Lift Drag Data on Bodies of Revolu- t ion f rom F ree -F l igh t Investigations. NASA TR R-100 ( supersedes NACA TN 4201), 1961


Margol is , K. : Theore t ica l Evaluation of the P r e s s u r e s , F o r c e s , and Moments a t Hypersonic Speeds Acting on A r b i t r a r y Bodies of Revolution Undergoing Separa te and Combined Angle-of-Attack and Pitching Motions. NASA TN D- 652, 1961

Arms t rong , W. 0. : Hypersonic Aerodynamic Cha rac t e r i s t i c s of Severa l S e r i e s of Lifting Bodies Applicable to Re- en t ry Vehicle Design. NASA T M X- 536, 196 1

F le tcher , H. S. and Wolhart , W. D. : Damping i n P i t ch and Sta t ic Stabil i ty of Supersonic Impact Nose Cones, Shor t Blunt Subsonic Impac t Nose Cones, and Manned Re-en t ry Capsules a t Mach Numbers f r o m 1. 93 to 3. 05. NASA T M X-347, November 1960

Briggs , B. R. : The Numer ica l Calculation of Flow P a s t Conical Bodies Sup- porting Ell ipt ic Conical Shock Waves a t Fini te Angles of Incidence. NASA TN D-340, November 1960

Johnson, C. T. : Investigation of the Charac te r i s t i cs of 6- Foot Drogue-Stabil i- zation Ribbon Parachutes a t High Altitudes and Low Supersonic Speeds. NASA T M X- 448, November 1960

Smith, F. M. : A Wind-Tunnel Investigation of the Aerodynamic Cha rac t e r i s - t ics of Bodies of Revolution a t Mach Numbers of 2.37, 2. 98 and 3. 90 a t Angles of Attack to 90 Degrees . NASA TM X-311, August 1960

Gran t , F. C. : Analysis of Low-Acceleration Lifting En t ry f r o m Escape Speed. NASA TN D-249, June 1960

Wehrend, W. R . , Jr. and Reese , D. E . , Jr. : Wind Tunnel Tes t s of the Stat ic and Dynamic Stability Cha rac t e r i s t i c s of Fou r Bal l is t ic Re-en t ry Bodies. NASA TM X-369, 1960

Rainey, R. W. : Working Char t s fo r Rapid Predic t ion of F o r c e and P r e s s u r e Coefficients on A r b i t r a r y Bodies of Revolution by Use of Newtonian Concepts. NASA TN D-176, December 1959

Crawford, D. H. : Investigation of the Flow over a Spiked-Nose Hemisphere - Cylinder a t a Mach Number of 6 .8 . NASA TN D- 118, December 1959

Lockwood, V. E. and McKinney, L. W. : Lift and Drag Charac te r i s t i cs a t Subsonic Speeds and a t a High Mach Number of 1. 9 of a Lifting C i r cu l a r Cylin- d e r with a Fineness Ratio of 10. NASA TN D- 170 , December 1959

Gran t , F. C. : Importance of the Variat ion of Drag with Lift in Minimization of Satel l i te Ent ry Accelera t ion. NASA TN D- 120, October 1959

Trou t , 0. F. , Jr. : Exper imenta l Investigation of Severa l Copper and Beryl-. l i um Hemisphere Models i n A i r a t Stagnation T e m p e r a t u r e of 2000 F to 3600 F. NASA TM X-55, Sep tember 1959


Henderson, A. , J r . and Johns ton, P. J. : Fluid-Dynamic P r o p e r t i e s of Some Simple Sharp and Blunt-Nosed Shapes a t Mach Numbers f r o m 16 to 24 In. Helium Flow. NASA Memo 5-8-59L, June 1959

Sommer , S. C. and Tobak, M. : Study of the Osc i l l a to ry Motion of Manned Ve- hic les Entering the E a r t h ' s Atmosphere . NASA Memo 3 - 2 - 59A, Apr i l 1959

Kehlet, A. B. and Pa t t e r son , H. G. : Free -F l igh t Tes t of a Technique fo r In- flating a n NASA 12- Foot Diamete r Sphere a t High Altitudes. NASA Memo 2 - 5- 59L, January 1959

Chapman, D. R. : An Approximate Analytical Method for Studying En t ry into P lane ta ry Atmospheres . NASA TR R- 11, 1959

Letko, W. : Exper imenta l Investigation a t a Mach Number of 3 . 11 of the Lift, Drag and Pitching-Moment Cha rac t e r i s t i c s of a Number of Blunt, Low- Fine- ness -Rat io Bodies. NASA Memo 1 - 18- 59L, 1959

T u r n e r , K. L. and Shaw, D. S. : Wind- Tunnel Investigation a t Mach Numbers f r o m 1.60 to 4. 50 of the Stat ic-Stabil i ty Cha rac t e r i s t i c s of Two Non-Lifting Ve- hicles Suitable fo r Re-entry . NASA Memo 3-2- 59L, 1959

Rainey, R. W. : Working Char t s f o r Rapid Pred ic t ion of F o r c e and P r e s s u r e Coefficients on A r b i t r a r y Bodies of Revolution by Use of Newtonian Concepts. NASA TN D- 176, December 1959

F l e t che r , H. W. and Wolhart , W. D. : Damping in Pi tch and Static Stability of a Group of Blunt-Nose and Cone-Cyl inder-Flare Models a t a Mach Number of 6.83. NASA Memo 5 - 6 - 5 9 ~ , 1959

F i s h e r , L. R. : Equations and Char t s f o r Determining the Hypersonic Stability Derivatives of Combinations of Cone F r u s t u m s Computed by Newtonian Impact Theory. NASA TN D- 149, 1959

Chapman, D. R. : Decelera t ion during Ent ry in P lane ta ry Atmospheres . N- 65794, November 1958

F i she r , L. R. ; Keith, A. L . , Jr . ; and DiCamillo, J. R. : Aerodynamic Charac te r i s t i cs of Some Fami l i e s of Blunt Bodies a t Transonic Speeds. NASA Memo 10-28-58L, November 1958

Col t rane, L. C. : Stabil i ty Investigation of a Blunt Cone and a Blunt Cylinder with a Square B a s e a t Mach Numbers f r o m 0.64 to 2. 14. NACA R M L58G24, September 1958

Tobak, M. and Allen: Dynamic Stability of Vehicles T rave r s ing Ascending o r Descending Pa ths through the Atmosphere . NACA TN 4275, July 1958

APPENDIX A GER- 126 16

Speegle, K. C. ; Charvin, L. T. ; and Heber l ig , J. C. : Heat T r a n s f e r f o r Mach Numbers up to 2 .2 and P r e s s u r e Distr ibutions f o r Mach Numbers up to 4. 7 f r o m Flight Investigation of a F la t - Face- Cone and a Hemisphere - Cone. NACA RM L58B18, May 1958

Kehlet, A. B. : Some Effects of Reynolds Number on the Stability of a S e r i e s of Flared-Body and Blunted-Cone Models a t Mach Numbers f r o m 1. 62 to 6 .86 . NACA RM L57J29, January 1958

Egge r s , A. J. , J r . : Recovery Dynamics - Possibi l i ty of Non-destructive Land- ing. N-60624, 1958

Beckwith, I. E. and Gal lagher , V. V. : Heat T r a n s f e r and Recovery T e m p e r a - t u r e s on a Sphere with Lamina r , Transi t ional , and Turbulent Boundary Laye r s a t Mach Numbers of 2.00 and 4.15. NACA TN 4125, December 1957

Allen, H. Julian: Motion of a Ball ist ic Miss i l e Angularly Misaligned with the Flight Pa th upon Entering the Atmosphere and i ts Effect upon Aerodynamic Heating, Aerodynamic Loads , and Miss Distance. NACA TN 4048, October 1957

Rel le r , J. O . , J r . : Heat T r a n s f e r to Blunt Nose Shapes with Lamina r Bound- a r y Laye r s a t High Supersonic Speeds. NACA RM A57F03A, N62-64403, August 1957

Centolonzi, F. T. : Charac t e r i s t i c s of a 40-Dcgrce Cone for Measuring Mach Numbers , Total P r e s s u r e , and Flow Angles a t Supersonic Speeds. NACA TN 3967, May 1957

C a r t e r , H. S. and Bre s se t t e , W. F. : Heat -Transfe r and P r e s s u r e Dis t r ibution on Six Blunt Noses a t a Mach Number of 2 . NACA RM L57C18, Apr i l 1957

Egge r s , A. J . , J r . : Re-en t ry and Recovery of a High-Drag Satell i te Init ial ly in C i r cu l a r Orbi t about the Ear th . N-59811, F e b r u a r y 1957

Penland, J. A. : Aerodynamic Charac te r i s t i cs of a C i r cu l a r Cylinder a t Mach Number 6.86 and Angles of Attack up t o 90 Degrees . NACA TN 3861 ( supe r - sedes RM L54A14), January 1957

Love, E. S. : Base P r e s s u r e a t Supersonic Speeds on Two-Dimensional A i r - foils and on Bodies of Revolution with and without F ins having Turbulent Bound- a r y Laye r s . NACA T N 3819, January 1957

Kaplan, C. : Flow of a Compress ib le Fluid P a s t a Sphere . NACA TN 762

Seiff, A. ; Sommer , S. C. ; and Canning, T . N. : Some Exper iments a t High Supersonic Speeds on the Aerodynamic and Boundary- Laye r Trans i t ion Charac- t e r i s t i c s of High Drag Bodies of Revolution. NACA RM A56105, 1957


Tobak, M. and Wehrend, W. R. : Stabil i ty Der ivat ives of Cones a t Supersonic Speeds. NACA TN 3788, Sep tember 1956

Le i s s , A. : Free -F l igh t Investigation of Effects of Simulated Sonic Turbojet Exhaust on the Drag of Twin- J e t Boattai l Bodies a t Transonic Speeds. NACA RM L56D30, N62-63881, July 1956

B r o m m , A. F. , J r . and Goodwin, J. M. : Investigation a t Supersonic Speeds of the Variat ion with Reynolds Number and Mach Number of the Total , Base and Skin-Fr ic t ion Drag of Seven Boattai l Bodies of Revolution Designed for Minimum Wave Drag. NACA TN 3708 ( supe r sedes RM L53129b), June 1956

Jorgensen, L . H. and Pe rk in s , E. W. : Investigation of Some Wake Vortex Charac te r i s t i cs of a n Inclined Ogive- Cylinder Body a t Mach Number 1. 98. NACA, August 1955

Rel le r , J. 0. , Jr. and Hamaker , F. M. : An Exper imental Investigation of Base P r e s s u r e Charac te r i s t i cs of Non-lifting Bodies of Revolution a t Mach Numbers f r o m 2. 73 to 4. 98. NACA TN 3393, March 1955

Chapman, D. R. : An Analysis of the Cor r ido r and Guidance Requirements fo r Superc i rcu la r Ent ry into P lane ta ry Atmospheres . NASA TR R-55

Stine, H. A. and Wanlass , K. : Theore t ica l and Exper imental Investigation of Aerodynamic-Heating and I so the rma l Hea t -Transfe r P a r a m e t e r s on a Hemis- pher ica l Nose with Lamina r Boundary Laye r a t Supersonic Mach Numbers . NACA TN 3344, December 1954

Sacks, A. H. : Aerodynamic F o r c e s , Moments, and Stability Derivatives for Slender Wings and Bodies of Gene ra l C r o s s Section. NACA TN 3283, 1954

Messing, W. E. ; Rabb, L. ; and Disher , J. H. : Pre l imina ry Drag and Heat T r a n s f e r Data Obtained f r o m Air-Launched Cone-Cylinder T e s t Vehicle over Mach Number Range f r o m 1. 5 to 5. 18. NACA RM E53104, November 1953

Grisby, C. E . and Ogburn, E . L . : Investigation of Reynolds Number Effects fo r a Se r i e s of Cone-Cylinder Bodies a t Mach Numbers 1. 62, 1. 93 and 2. 41. NACA RM L53H22, October 1953

Hear th , D. P. and Gordon, G. C. : Investigation a t Supersonic Speeds of a n Inlet Employing Conical Flow Separat ion f r o m a P robe Ahead of a Blunt Body. NACA RB E52K18, 19 January 1953

Robins, A. W. : P r e l i m i n a r y Investigation of the Effects of Severa l Seeker - Nose Configurations on the Longitudinal Cha rac t e r i s t i c s of a Canard-Type Miss i l e a t a Mach Number of 1. 60. NACA RM L53I 18, 1953

Equations, Tables and Char t s f o r Compress ib le Flow. NACA Report 1135, 1953


Pilano, R. 0. : P r e l i m i n a r y F ree -F l igh t Investigation of the Zero-Li f t Drag Penal t ies of Several. Miss i l e Nose Shapes for In f ra red Seeking Devices. NACA RM L52F23, 9 December 1952

Ehre t , D. M. : Accuracy of Approximate Methods fo r Predic t ing P r e s s u r e s o r Pointed Non-lifting Bodies of Revolution in Supersonic Flow. NACA T N 2764, August 1952

Dennis, D. H. and Cunningham, B. E. : F o r c e s and Moments on Pointed and Blunt-Nosed Bodies of Revolution a t Mach Numbers f r o m 2. 75 to 5. 00. NACA RM A52F22, August 1952

Eggers , A. J. , J r . and Savin, R. C. : Approximate Methods fo r Calculating the Flow about Non-lifting Bodies of Revolution a t High Supersonic Ai rspeeds . NACA TN 2579, December 1951

F e r r i , A. : Supersonic Flow around C i r cu l a r Cones a t Angles of Attack. NACA Report No. 1045, 1951

F e r r i , A. : The Method of Charac te r i s t i cs for the Determination of Supersonic Flow over Bodies of Revolution a t Sma l l Angles of Attack. NACA Report 1044, 1951

Hart , R. G. : Flight Investigation of the Drag of Round-Nosed Bodies of Revo- lution a t Mach Numbers f r o m 0. 6 to 1. 5 using Rocket-Propel led Tes t Vehicles. NACA RM L51E25, 1951

Herber le , J. W. ; Wood, G. P. and Gooderurn, P. B. : Data on Shape and Lo- cation of Detached Shock Waves on Cones and Spheres . NACA TN 2000, Janu- a r y 1950

F e r r i , A. : Supersonic Flow around C i r cu l a r Cones a t Angles of Attack. NACA TN 2236, 1950

Chapman, D. R. : An Analysis of Base P r e s s u r e a t Supersonic Speeds , and Comparison with Exper iment . NACA TN 2137, 1950

Alexander , S. R. : Flight Investigation a t Low Supersonic Speeds to Determine the Effectiveness of Cones and a Wedge in Reducing the Drag of Round-Nose Bodies and Airfoils . NACA RM L8L07a, March 1949

F e r r i , A. : The Methods of Cha rac t e r i s t i c s f o r the Determinat ion of Super- sonic Flow-Over Bodies of Revolution a t Smal l Angles of Attack. NACA TN 1809, 1949

Mire l s , H. : Theore t ica l Wave Drag and Lift of Thin Supersonic Ring Airfoi ls . NACA TN 1768, 1 948


I1 - WRIGHT FIELD DOCUMENTS

Nebiker, F. R. : Aerodynamic Deployable Dece le ra to r Pe r fo rmance Evaluation P r o g r a m , A F F D L - T R - ~ ~ - ~ ~ , May 1965

Heinrich, H. G . ; Hess , R. S. ; and S tumbr i s , G. : Drag Cha rac t e r i s t i c s of P l a t e s , Cones and Spheres in the Wake of a Cyl indr ical Body a t Transonic Speeds. RTD-TDR-63-4023, AD-457055, X65- 13630, January 1965

Giemza , C. J. and Hunter , W. B. : St ruc tu ra l Heat Shield fo r Re-en t ry and Hypersonic Lift V e h i c l e s / ~ i ~ h Tempera tu r e Composite S t ruc ture . ML-TDR- 64-267, P a r t 1 , Vol I , AD-459376, X65-14059, January 1965

Heinrich, H. G. and Hess , R. S. : Drag Charac te r i s t i cs of Severa l Two-Body Sys tems a t Transonic and Supersonic Speeds. RTD-TDR-63-4226, December 1964

Heinrich, H. G . ; Hess , R. S. ; and S tumbr i s , G. : Drag Coefficients of Seve ra l Bodies of Revolution a t Transonic and Supersonic Velocity. ASD-TDR-63-663, AD-608303, N65- 12138, September 1964

Haak, E. L. and Niccum, R. J.: P r e s s u r e Distr ibution Measurements of Conventional Ribbon Parachutes in Supersonic Flow. ASD- TDR-63 - 662, AD- 608305, September 1964

Brockman, H. : Development of Nomex Mesh Mater ia ls . ML- TDR-64-208, AD-607890, September 1964

Myers , E. C. : Proceedings , Symposium on Parachute Technology and Evalu- ation. Vol 11, FTC-TDR-64- 12

Myers , E. C. : Proceedings , Symposium on Parachute Technology and Evalu- ation. Vol I, FTC- TDR- 64- 12, Sep tember 1964

RTC-TDR-64- 12: Symposium on Parachute Technology and Evaluation - P r o - ceedings. Edited by E a r l C. Meye r s , Ca l i f . , A i r F o r c e Flight T e s t Center , A i r F o r c e Sys tems Command, Edwards A i r F o r c e Base , 12 September 1964

Nickel, W. E. and S ims , L. W. : Study a n Exploratory F ree -F l igh t Investiga- tion of Deployable Aerodynamic Decelera t ions Operating a t High Altitudes and at High Mach Numbers . FDL-TDR-64-3 5, Vol I, July 1964


Pe t e r s en , P. E . : Study of Pa rachu t e Pe r fo rmance and Design P a r a m e t e r s fo r High Dynamic P r e s s u r e Operation. FDL-TDR-64-66, May 1964

Chernowitz, G. and DeWeese, J. H. : Per fo rmance of and Design C r i t e r i a fo r Deployable Aerodynamic Dece le ra to rs . (Second m a j o r revis ion of the USAF Parachute Handbook), ASD- TR-61- 579, AD-429971, December 1963

Kaman Ai r c r a f t Corpo:ration: Investigation of Stored Energy Rotors fo r Recov- e ry . ASD-TDR-63-745, December 1963

Dolbin, B. J. ; Newell, F. D. ; and Schelhorn, A. E. : Development and Flight Cal ibra t ion of a Var iable-Drag Device on a Var iable Stability T-33 Airplane. ASD-TDR-62-910, AD-425705, N64-13627, November 1963

ASD- TDR- 63 -453 : Flight Vehicle S t ruc tu r a l Design Cr i t e r i a , Recovery Phase . September 1963

Frees ton , W. D . , J r . and Carde l la , J. W. : New and Improved Mater ia l s fo r Expandable S t ruc tu r e s , P h a s e 1 - Weaving of Stranded Metal Yarns . ASD- TDR- 62- 542, September 1963

Epting, J. L. , J r . : Silicone Finished Glass F ibe r Tapes and Webbings fo r Dece le ra to rs . ASD-TDR-63-808, AD- 422524, September 1963

F o e r s t e r , A. F. ; e t a l : Analytical and Exper imental Investigation of Coated Metal Fab r i c Expandable S t ruc tures fo r Aerospace Applications. ASD-TDR- 63- 542, August 1963

ASD- TDR- 63 -32 9: Proceedings of Retardat ion and Recovery Symposium. Ohio Flight Acces so r i e s L a b . , Aeronaut ical Sys tems Division, A i r F o r c e Sys tems Command, May 1963

Hartofi l is , S. A. : P r e s s u r e Measurement a t Mach 19 fo r a Winged Re-en t ry Configuration: P a r t of a n Investigation of Hypersonic Flow Separation and Con- t r o l Charac te r i s t i cs . ASD-TDR-63-3 19, May 1963

Cosken, R. J. and Chu, C. C.: Investigation of the High Speed Impact Behavior of Fibrous Mater ia l s , P a r t 111, Impact Cha rac t e r i s t i c s of Parachute Mater ia l s . WADD-TR-60-511, May 1963

Proceedings of Retardat ion and Recovery Symposium. (Dayton, November 13 - 14, 1962 Final Report ) , ASD-TDR-63-329, AD-408772, May 1963

ASD-TR-63-69: Design and Ins t rumentat ion Testing fo r a Hypersonic P a r a - chute F r e e - Flight T e s t Capability. May 1963

Gran , W. M. ; Musil , J. L. ; and F ra t amico , J. A. : Design and Ins t rumenta- tion Testing for a Hypersonic Parachute F ree -F l igh t T e s t Capability (Phase s I1 and 111). ASD-TR-63-64, May 1963


Neff, R. J. : Development of HT-1 Mater ia l s for Pe r sonne l Pa rachu t e Packs and Harnes se s . ASD-TDR-63 -3 12, Apr i l 1963

Neff, R. J. : Development of HT-1 Mater ia l s for Dece le ra to rs . ASD-TDR-63- 248, March 1963

S ims , L. W. : Analytical and Exper imental Investigation of Supersonic P a r a - chute Phenomena. ASD-TDR-62-844, Chicago, Ill. , Cook Technological Cen- t e r , Feb rua ry 1963 (CONFIDENTIAL)

ASD-TDR-62- 542: New and Improved Mater ia l s f o r Expandable S t ruc tures . P a r t IV - Phase 111, Re-en t ry Coatings, October 1963; P a r t V - Phase IV, High Tempera tu r e Pro tec t ive Study, Feb rua ry 1963

Walcott, W. B. : Study of Parachute Scale Effects. ASD-TDR-62- 1023, N63- 13009, January 1963

Hung, F. C. : Flight Vehicle Struc.tura1 Design C r i t e r i a , Recovery Phase . ASD-TDR-63- 453, AD-423012

Alexander, W. C. : hves t i ga t i on to Dete rmine the Feasibi l i ty of Using Inflat- able Balloon-Type Drag Devices fo r Recovery Applications in the Transonic , Supersonic and Hypersonic Flight Regime. P a r t 11, Mach 4 to Mach 10 Feas i - bility Investigation, ASD-TDR-62- 702, December 1962

Abbott, D. E. ; Holt, M. ; and Nielsen, J. N. : Investigation of Hypersonic Flow Separation and i t s Effects on Aerodynamic Control Charac te r i s t i cs , ASD-TDR- 62- 963, November 1962

Ligon, W. M. : Resea rch and Development on High Altitude, High Speed Crew Escape Sys tems Testing Concept. Vol I - Subsystem and Simulation Investiga- tion, ASD-TDR-62-47 1 , Vol I , Dal las , Tex. , Vought Astronaut ics , November 1962

Huang, R. S. : R e s e a r c h and Development on High Altitude, High Speed Crew Escape Sys tems Testing Concepts. Vol I1 - T e s t Vehicle Investigation, ASD- TDR-62-471, Vol 11, Dallas, Tex. , Vought Astronaut ics , November 1962

Meyer , R. A. : A Study of the Load Bear ing Behavior and Other Cha rac t e r i s - t i c s Influencing Vibration o r F lu t t e r in Dece le ra to r Ribbons. ASD- TDR- 62- 988, November 1962

Aebischer , A. C. : Investigation to Determine the Feasibi l i ty of Using Inflat- able Balloon- Type Drag Devices fo r Recovery Applications in the Transonic , Supersonic and Hypersonic Flight Regimes - P a r t 1 , Functional and Per for rn- ance Demonstrat ion. ASD- TDR- 62-702, September 1962

Heinrich, H. G . and Haak, E . L. : Stability and Drag of Parachutes with Vary- ing Effective Poros i ty . ASD- T D R - ~ ~ - 100, Sep tember 1962


Lubinsky, T. P. : T r a c k T e s t s of Canopy Escape Capsule. ASD-TDR-62-404, August 1 96 2

Epstein, A. and Hamilton, A. F. : Study of Design P a r a m e t e r s fo r S t ruc ture Subject to Aerodynamic Heating. ASD-TR-61- 95, August 1962

Cobb, E. S . , Jr. : High Strength, G la s s F ibe r Webbings, Tapes and Ribbons fo r High Tempera tu r e P r e s s u r e Packaged Dece le ra to rs . ASD-TDR-62-518, July 1 962

Dawn, F. S. and Ross , J. H. : Investigation of Polybenzimidazole F i b e r s a t High Tempera ture . ASD- TDR-62- 43 5, July 1962

Chew, F. E. ; Oling, L. ; and Clutz, H. A. : Investigation of Stabilization and Control Sys tems for Application to Aerospace Vehicle Escape Capsules. ASD- TDR-62-243, June 1962

Investigation of Landing Point Control of Re-en t ry Vehicles Utilizing Variable A r e a Aerodynamic Dece le ra to rs Incorporating Lift. ASD-TDR-62-287, June 1962

Berndt, R. J. : Supersonic Parachute Research . ASD -TDR-62-236, May 1962

Heinrich, H. G. and Haak, E. L. : Stability and Drag of Parachutes with Vary- ing Effective Porosi ty . ASD-TDR-62- 100, Apr i l 1962

Knacke, T. W. and Dimmick, D. T . : Design Analysis of F ina l Recovery P a r a - chutes B- 70 Encapsulated Seat and the USD- 5 Drone. ASD- TDR-62-75, Apr i l 1962

Tyndall, R. R. : Analytical and Empi r i ca l Investigation of a Completely Flexi- ble Rotor Blade. ASD Technical Memorandum ASRMPT- TM- 628, March 1962

ASD-TR-61- 100: Feasibi l i ty Study of Hypersonic Parachute F r e e Flight Tes t Capability - Phase I. Chicago, Ill . , Cook Resea rch Labs . , Phase I, March 1962

Johnson, D. E. ; Newton, E. H. ; Benton, E. R. ; Ashman, L. E. and Knapton, D. A. : Metal Fi laments fo r High-Temperature Fab r i c s . ASD- TR-62- 180, Feb rua ry 1962

Coskren, R. J. and Chu, C. C. : Investigation of the High Speed Impact Be- havior of F ibrous Mater ia l s , P a r t I1 - Impact Charac te r i s t i cs of Parachute Mater ia l s . ASD-TR-60-511, F e b r u a r y 1962

The P rob l em of Descent to the Surface of the E a r t h and Planets . A i r F o r c e Sys tems Command, Wright- Pa t t e r son AFB, Fore ign Technology Division, N63- 18435, F e b r u a r y 1962


G l a s s e r , P. E. and M e r r a , S. : T h e r m a l Radiation Effects on Dece le ra to r Mater ia ls . ASD-TDR-62- 185, F e b r u a r y 1962

ASD-TR-62- 180: Metal F i lament for High Tempera tu r e Fabr ics . F e b r u a r y 1962

Dawn, F. S. and Ross , J. H. : Investigation of the T h e r m a l Behavior of Graph- i t e and Carbon-Bas ed Fibrous Mater ia l s . ASD- TDR-62- 782

Heinrich, H. G. and Haak, E . L. : The Drag of Cones, P l a t e s and Hemispheres in the Wake of a Forebody in Subsonic Flow. ASD-TR-61-587, December 1961

Milhoan, F. M. ; Vorachek, J. J. ; and DfAl lura , J. : Investigation of Escape Capsule Sys tems fo r Mult i -Place Ai rc ra f t . P a r t s I and 11, WADDTR-57-329, December 196 1

Study of a Drag Brake Satell i te Recovery System. AVCO-Everett Resea rch Lab . , ASD-TR-61-348, November 1961

Broder ick , M. A. and T u r n e r , R. D. : Design Cr i t e r i a and Techniques for Deployment and Inflation of Aerodynamic Drag Devices. ASD- TR-6 1 - 188, November 196 1

Wells , J. A. : Design Study of the Capsule Escape Vehicle Parachute Recovery Sys t em Hardware . ASD-TR-61- 178, Vol I, October 1961

Coplan, M. J. and Frees ton , W, D. , J r . : High Speed Flow and Aerodynamic Heating Behavior of Porous F ibrous S t ruc tures . N- 106-882, October 196 1

Nielsen, J. N. ; Burnel l , J. A. ; and Sacks , A. H. : Investigation of Flexible Rotor Sys tems , Resul ts of Phase s I and 11. ASD-TR-61-660 September 1961

Pe t e r s en , P. E. : Study of Parachute Pe r fo rmance a t Low Supersonic Deploy- men t Speeds: Effects of Changing Scale and Clustering. ASD-TR-61- 186, July 1961

Champney, W. B. ; Athans, J. B. ; and Mayerson, C. D. : A Study of Hyper- sonic Aerodynamic Drag Devices - Final Technical Report . WADC- TR- 59-324, P a r t 11, Buffalo, N. Y . , Corne l l Aeronaut ical L a b s . , Inc . , June 1961

Heinrich, H. G. and Haak, E. L. : The Drag of Cones, P la tes and Hemispheres i n the Wake of a Forebody in Subsonic Flow. ASD-TR-61-587, December 1961

Milhoan, F. M. ; Vorachek, J. J. ; and DfAl lura , J. : Investigation of Escape Capsule Sys tems for Multi- P l ace Ai rc ra f t . P a r t s I and 11. WADD- TR- 57-329, December 1961

Study of a Drag Brake Satell i te Recovery System. AVCO-Everett Resea rch Lab. , ASD-TR-61-348, November 1961


Broder ick, M. A. and T u r n e r , R. D. : Design C r i t e r i a and Techniques fo r Deployment and Inflation of Aerodynamic Drag Devices. ASD-TR-61- 188, November 196 1

Wells , J. A. : Design Study of the Capsule Escape Vehicle Parachute Recovery Sys tem Hardware . ASD-TR-61-178, V o l I , October 1961

Coplan, M. J. and F ree s ton , W. D. , Jr. : High Speed Flow and Aerodynamic Heating Behavior of Porous Fibrous S t ruc tures . N- 106-882, October 1961

Nielsen, J. N. ; Burnel l , J. A. ; and Sacks , A. H. : Investigation of Flexible Rotor Sys tems , Results of Phase s I and 11. ASD-TR-61-660 September 1961

Pe t e r s en , P. E. : Study of Parachute Pe r fo rmance a t Low Supersonic Deploy- ment Speeds : Effects of Changing Scale and Clustering. ASD- TR- 6 1 - 186, July 1961

Champney, W. B. ; Athans, J. B. ; and Mayerson, C. D. : A Study of Hyper- sonic Aerodynamic Drag Devices - Fina l Technical Report . WADC-TR- 59- 324, P a r t 11, Buffalo, No Y. , Cornel l Aeronaut ical Labs . , Inc. , June 196 1

Engs t rom, B. A. : Per fo rmance of Trai l ing Aerodynamic Dece le ra to rs a t High Dynamic P r e s s u r e s . Phase IV, WADD-TR-58-284, P a r t IV, June 1961

G r o s s , R. S. and Riffle, A. B. : Per fo rmance Evluation of the Vortex Ring Parachute Canopy. ASD-TR-61- 41 0, June 196 1

Nebiker, F. R. and Karaffa, N. T. : Feasibi l i ty Study of a n Inflatable Type Stabilization and Decelera t ion Sys tem for High-Altitude and High-Speed Recov- e ry . ASD-TR-60- 182, August 1961

Abbott, N. J. : Some Effects of Compress ion and Heat on Dece le ra to r Ma- t e r i a l s . WADD- TR- 60- 588, June 196 1

Engs t rom, B. A. and Lang, R. P. : Per fo rmance of Trai l ing Aerodynamic Dece le ra to rs a t High Dynamic P r e s s u r e s . P a r t 4, WADD-TR-58-284, Junc 1961

Pe t e r s en , P. E . : Study of Parachute Pe r fo rmance a t Low Supersonic Deploy- - . ment Speeds; Effects of Changing Scale and Clustering. ~ ~ ~ - ~ ~ - 6 1 - 1 8 6 , May 1961

McGrath, J. C. : Fibrous Mater ia l s fo r Dece le ra to rs and S t ruc tures . ASD- TN-61-59, May 1961

Engs t rom, B. A. : Per fo rmance of Trai l ing Aerodynamic Dece le ra to rs a t High Dynamic P r e s s u r e s . Phase s V and VI, WADD TR-58-284, P a r t V, May 1961


Ruprecht, F. A. and P r i m a , C. D. : A Study of Design and Mater ia l s f o r Low Cost A e r i a l Delivery Pa rachu t e s . Technical Report 11, Cook Resea rch L a b s . , Contract AF33 (6 16)- 6009, Pa rachu t e Section, Crew Equipmcnt Branch, ASD, Apr i l 1961

Rockhold, V. G. ; Onspaugh, C. M. ; and March, W. L. : Study to Determine Aerodynamic Cha rac t e r i s t i c s on Hypersonic Re-en t ry Configurations. P a r t I - Experimental Phase , Vol 2 - Exper imenta l Report - Mach Numbers 5, WADD- TR-61- 56, March 196 1 , (CONFIDENTIAL)

Engholm, G. ; L i s , S. J. ; and Bambenek, R. A. : Instantaneous Loca l Tem- pe ra tu r e s of Aerodynamic Dece le ra to rs . P a r t I1 T h e r m a l P rope r t i e s , WADD- TR-60-670, F e b r u a r y 1961

Cheatham, R. G. ; Shank, M. E. ; and Backer , S. : Texti le F i b e r s in High Tempera tu r e Applications. TR-60-327, F e b r u a r y 1961

Engholm, G . , e t a l . : Instantaneous Local Tempera tu r e s of Aerodynamic De- ce l e r a to r s . P a r t I, WADD-TR-60-670, F e b r u a r y 1961

Study of a Drag Brake Satell i te Recovery System. Resul ts of P h a s e I, WADD- TR-60-775, January 1961, AD254673

Engholm, G. ; Baschie re , R. J. ; and Bambenek, R. A. : Instantaneous Local Tempera tu r e s of Aerodynamic Dece le ra to rs . P a r t I Methods of Predicting, WADD-TR-60-670, December 1960

Li t t le , C. 0. , J r . : Therma l and Gamma Radiation Behavior of a New High Tempera tu r e Organic F iber . WADD-TN-60-299, December 1960

Engs t rom, B. A. : Per fo rmance of Trai l ing Aerodynamic Dece le ra to rs a t High Dynamic P r e s s u r e s . Phase 111, WADD-TR-58-284, P a r t 111, December 1960

Heinr ich, H. G . : Some Resea rch Efforts Related to P rob l ems of Aerodynamic Deceleration. WADD- TN-276, November 1960

Coats , J. D. : Static and Dynamic Test ing of Conical Trai l ing Dece le ra to rs for the Persh ing Re-en t ry Vehicle. AEDC-TD-60- 188, October 1960

Serbin , J. and Becker , H. : The Design and Evaluation of Heat Stabilized Tapes and Webs. WADD-TR-60-252, AD249409, October 1960

Walcok, W. S. : Deter iora t ion of Texti le Mate r ia l s by Ultraviolet Light. WADD-TR-60-510, AD249237, October 1960

Mileaf, H. (ed): Handbook of F ibrous Mater ia l s . AD249782, WADD-TR-60- 584, October 1960


Mileaf, H. : Handbook, P a r t 1 of F ibrous Mater ia l s . WADD- TR-60- 584, Oc- tober 1960

Chu, C. C. ; e t a l . : Investigation of the High Speed Impac t Behavior of Fibrous Mater ia l s . P a r t I, Design and Apparatus , WADD-TR-60-511, AD-247493, Sep- t e m b e r 1960

J a i l e r , R. W. ; Fre i l i ch , G. ; and Norden, M. L . : Analysis of Heavy Duty Parachute Reliability. Amer i can Power Je t Co . , WADD-TR-60-200, AD- 246490, June 1960

Copland, M. J. ; Power s , D. H . , J r . ; Bar i sh , G. ; and Valko, E. I. : Poss ib le Application of Organic F i b e r s in High Tempera tu r e Environment. WADD- TR- 60- 9, June 1960

Lamber t son , W. A. ; et a l . : Continuous F i lament Ce ramic F ibe r s . WADD-TR- 60-244, June 1960

Brandt , H. H. and Linden, L. : Effects of Picks pe r Inch and Finishing P r o - cedures on the P rope r t i e s of 1. l -ounce Nylon Ripstop Parachute Fabr ic . Tex- t i le Se r i e s Report No. 113, Q u a r t e r m a s t e r Resea rch and Engineering Com- mand, AD-241246, June 1960

Hankey, W. L. ; Neumann, R. D. ; and Flinn, E. H. : Design P rocedu re s fo r Computing Aerodynamic Heating a t Hypersonic Speeds. WADC-TR- 59- 6 10, June 1960

Champney, W. B. and Engel, B. : A Study of Hypersonic Aerodynamic Drag Devices. In te r im Technical Report (unclassif ied t i t le) . WADC TR- 59-324, Apr i l 1 96 0 (CONFIDENTIAL)

Scshadr i , C. V. ; et a l . : A i r Flow Cha rac t e r i s t i c s of Parachute F ibe r s a t Simulated High Alti tudes. WADC-TR- 59-374, March 1960

Will iams, R. B. and Benjamin, R. J. : Analysis of Webbing Impac t Data and Determination of Opt imum Inst rumentat ion to be Used in Conjunction with the Impacting of Webbing. WADC-TR-59-694, Impac t Behavior of Texti le Ma- t e r i a l s , Final Report , March 1960

Engs t rom, B. A. : Per fo rmance of Trai l ing Aerodynamic Dece le ra to rs a t High Dynamic P r e s s u r e s . Phase 11, WADD- TR- 58-284, P a r t 11, March 1960

Schoeck, P. A. ; e t a l . : Exper imenta l Studies fo r Determining Heat T r a n s f e r on the Ribbons of FIST-Type Parachutes . WADC-TN-59-345, Feb rua ry 1960

Hayes, J. E . ; Rose, P. H. ; and VanderVelde, W. E. : Analytical Study of a Drag Brake Control Sys tem for Hypersonic Vehicles. WADD-TR-60-267, January 1960


Engs t rom, B. A. : Per fo rmance of Trai l ing Aerodynamic Dece le ra to rs a t High Dynamic P r e s s u r e s . P a r t I1 - P h a s e I1 T e s t Resu l t s , WADD-TR-58-284, January 1960

Heinrich, H. G. : Analytical and Exper imenta l Consideration of the Velocity Distr ibution i n the Wake of a Body of Revolution. WADD Technical Report 60- 257, December 1959

Controlled Burn- Through of Re-en t ry Drag Chutes. Submitted to WADC on 7 December 1959 by Mater ia l s Technology, Inc.

Heinr ich, H. G. ; and Scipio, L. A. : Per fo rmance Charac te r i s t i cs of Extended Ski r t Parachute . WADC-TR- 59- 562, October 1959

Marsha l l , F. J. : Optimum Re-en t ry into the E a r t h ' s Atmosphere by u s e of a Var iable Control Force . The Universi ty of Chicago Insti tute fo r Sys tem Re- s e a r c h , WADC-TR-59-515, October 1959

Cornish, R. H. ; e t al . : Mass T r a n s f e r Cooling of Parachute Mater ia ls . WADC-TR- 58-684, AD229441, September 1959

Ruprecht, F. A. ; e t al . : A Study of Design and Mater ia l s for Development of Low Cost Ae r i a l Delivery Parachutes . WADC-TR- 59- 385, AD23 7460, Sep- t e m b e r 1959

Johnson, D. E. ; e t a l . : Candidate Mate r ia l s fo r High Tempera tu r e Fab r i c s . WADC-TR-59- 155, AD232975, September 1959

Tyndall , R. R. : Pre l imina ry Qualitative Evaluation of a Stored Energy Recov- e r y System. WADC-TN-59-267, July 1959

Newquist, E . A. ; Cassidy, M. D. ; Lindblom, C. W. ; and Sullivan, P. J. : De- velopment of a n Ejectable Nose Escape Capsule. WADC-TR- 59-493, June 1959

Heinrich, H. G. and Ibrahim, S. K. : Application of the Water Surface Wave Analogy in Visualizing the Wave P a t t e r n of a Number of P r i m a r y and Second- a r y Body combinations in Supersonic Flow. WADC-TR-59-457, September 1959

Chu, C. C. ; e t a l . : Development of Improved Nylon Webbings. WADC-TR- 58-509, AD211911, Apr i l 1959

Heinrich, H. G. : P r e s s u r e Distr ibution in Transonic Flow of Ribbon and Guide Surface Parachutes . WADC-TN- 59-32, F e b r u a r y 1959

Li t t le , C. O . , J r . : Amount of Deter iora t ion P r e s e n t in Parachutes Manufac- tured over 15 Yea r s Ago, WADC-TN-59-30, F e b r u a r y 1959


Ciffren, A. and Swenson, W. A. : Study and Development of Parachutes and Systems for In- Flight Landing Decelera t ion of Ai rc ra f t . P a r t 11, Development and T e s t Evaluation of the Ring Slot Parachute , WADC-TR-57-566, AD155707, January 1959

Drag Parachute Retract ing System. WADC-TR- 57- 57, January 1 959

Engs t rom, B. A. and Meyer , R. A. : Per fo rmance of Trai l ing Aerodynamic Dece le ra to rs a t High Dynamic P r e s s u r e s . P a r t I11 - Wind Tunnel Test ing of Rigid and Flexible Parachute Models, WADC-TR- 58-284, 1959

Meyer , R. A. : Wind Tunnel Investigation of Conventional Types of Parachute Canopies in Supersonic Flow. WADC-TR- 58- 532 AD202856, December 1958

Landis, M, B. and F r a m e , F. W. 111: Development of Core less Type Brands f o r u s e in Pe r sonne l Parachute Suspension Lines . WADC-TR-58-410, Decem- be r 1958

Meyer , R. A. : Wind Tunnel Investigation of Conventional Types of Parachute Canopies i n Supersonic Flow. WADC- TR- 58- 532, Chicago, Ill. , Cook Re- s e a r c h L a b s . , December 1958

Gimalowski, E . A. : Development of a Final Stage Recovery Sys tem for a 10,000 Pound Weight. WADC-TR- 59- 109, December 1958

Wilder, S. H. : Model Parachute T e s t in Ver t ical Wind Tunnel a t Wright A i r Development Center . WADC-TR-58-279, AD204424, September 1958

Theore t ica l Parachute Investigations. P r o g r e s s Repor t s , WADC Contract AF33(615)-3955, September 1958

Lit t lc , E. F. : An Evaluation of Fungicidal T rea tmen t s in Cotton Cargo P a r a - chute Webbings Stored a t College, Alaska. WADC-TR- 56-384, P a r t 11, AD- 155857, August 1958

E i r i ch , F. R. and Saad, I. : Improvement of T h e r m a l Stability of Text i le Fi- be r s . P r o g r e s s Report No. 8 , Annual Summary , Contract N140(132)5775B, Polytechnic Inst i tute of Brooklyn for U. S. Navy Supply Resea rch and Develop- men t Facil i ty, AD2 13554, July 1957 - 30 June 1958

Engs t rom, B. A. : Per fo rmance of Trai l ing-Aerodynamic Dece le ra to rs a t High Dynamic P r e s s u r e s . P a r t I , Development of T e s t Method and Tes t Equip- ment , WADD- TR- 58-284, June 1958

Foote, J. R. and Giever , J. B. : Study of Parachute Opening. P a r t 11, WADC TR- 56-253, June 1958

Rosenlof, K. D. : Drag Coefficient of FIST Ribbon Parachutes - Reefed and Fully Inflated. AFFTC-TR- 58- 5, AD13 1459, May 1958


Chu, C. C. ; e t a l . : Development of High Tenacity Heat Stable Dacron P a r a - chute I tems. WADC-TR-57-765, AD15551 1, May 1958

Klein, W. C. , et al . : Resea rch P r o g r a m for the Development of a Design P rocedu re to Engineer Parachute Fab r i c s . WADC-TR-58-65, AD 155517, May 1958

Aickinger, G. E. : Symposium on Miss i l e and Drone Recovery. WADC-TR-58- 125, AD151099, March 1958

Krizik, J. G. ; e t al. : Design Data on Biaxial F o r c e s Developed i n Parachute Fab r i c s . WADC-TR- 57-443, AD1 42208, December 1957

Ruoff, A. L. ; e t a l . : Aerodynamic Heating of Parachutes . WADC-TR-57- 157, AD1 42261, December 1957

Hartnet t , J. P. ; et a l . : Values of the Emiss iv i ty and Absorptivity of Parachute Fab r i c s . WADC-TN-57-443, AD1 51072, December 1957

Klein, W. G. ; e t a l . : Development of Design Data on the Mechanics of A i r Flow through Parachute Fab r i c s . WADC-TR-56-576, AD131055, September 1957

Ecke r t , E. R. G. ; et a l . : Trans i en t Tempera tu r e s of Parachutes during De- scent. WADC-TN-57-320, August 1957

Ecke r t , E. R. G. ; Hartnett , J. P. ; and Turnocliff: Trans ien t Tempera tu r e s of Parachutes during Descent and General ized T ra j ec to r i e s fo r F r e e Fall ing Bodies of High Drag. WADC-TN-57-320

Ruoff, Sin, and Frank: Aerodynamic Heating of Parachutes . WADC-TR- 57- 157

Downing, J. R. ; e t al. : Recovery Sys tems for Miss i l es and T a r g e t Ai rc ra f t . P a r t I11 - High Subsonic and Transonic Trackborne Parachute T e s t s , WADC Technical Report 5853, Cook Resea rch Lab . , December 1956

Downing, J. R. ; Harkins , H. V. ; McClow, J. H. , J r . ; and Pe t e r s en , P. E. : Recovery Sys tems for Miss i l es and T a r g e t A i r c r a f t , High Subsonic and T r a n - sonic T r a c k Borne Parachute Tes t s A F TR-5853, P a r t 111, December 1956

United Sta tes A i r F o r c e Parachute Handbook. WADC-TR-55-265, AD1 18036, December 1956

Cates , D. M. : A Study of the Effects of Chemicals on the P rope r t i e s of P a r a - chute Fab r i c s . WADC- TR- 55-3 40, Supplement 1 , AD1 10524, November 1956

Cates , D. M. : A Study of the Effects of Chemicals on the Strengths of Nylon and Dacron Parachute Fab r i c s . WADC-TR-56-288, AD1 10558, November 1956


Bomb Stabilization by Parachute . WADC-TR- 54- 4, AD1 10584, November 1956

Foote, J. R. and Giever , J. B. : Study of Parachute Opening. P h a s e I, WADC- TR-56-253, September 1956

Pounder, E. : Parachu te Inflation P r o c e s s Wind- Tunnel Study. WADC-TR- 56- 391, AD97180, Sep tember 1956

Templeton, J. G. : A Study of the Effects of Chemicals on the P rope r t i e s of Parachute Fab r i c s . WADC-TR-55-340, AD97243, September 1956

Coskrew, R. J. and Constantine, T. T. : Development of High Tenacity-Heat Stable Dacron Yarns . WADC-TR-55-297, AD97242, Sep tember 1956

Kaswell , E. R. and Coplan, M. J. : Development of Dacron Parachute Fab- r i cs . WADC-TR-55- 135, AD97241, Sep tember 1956

F e r r i , A. and Pal lone, A. : Note on the Flow on the R e a r P a r t of Blunt Bodies i n Hypersonic Flow. WADC-TN-56-294, July 1956

Wiant, H. W. ; and F rede t t e , R. 0: A Study of High Drag Configurations a s F i r s t Stage Decelera tors . WADC-TN-56-320, July 1956

Pounder , Edwin: Parachute Inflation P r o c e s s Wind Tunnel Study. P a r t I, In- f inite Mass Case , WADC-TN- 56-326, AD97182, July 1956

, Wiant, H. W. and F rede t t e , R. 0. : A Study of High Drag Configurations a s F i r s t Stage Dece le ra to rs . WADC-TN-56-320, July 1956

Thomson, G. ; et al. : Resea rch and Development of Abras ion Res i s tan t T rea t - men t s fo r Dacron Webbings. WADC-TR-55-3 13, AD97103, July 1956

Mil ler , C. R. : A Study of Parachute Seam Design Cr i t e r i a . P a r t 11, Investi- gation of the Strength of Nylon Webbing Joints. WADC-TR-56-3 13, AD1 10406, June 1956

Thomson, G. ; e t a l . : Resea rch and Development of Abrasion Res i s tan t T rea t - ments fo r Nylon Webbings. WADC-TR-56-151, AD103961, June 1956

Coplan, M. J. and Block, M. G. : A Study of Parachute Seam Design Cr i t e r i a . P a r t I, Investigation of the Strength of Nylon and Rayon Cloth Seams , WADC- TR-56-313, AD110407, June 1956

Neff, R. J. : The Development of Cur r en t Nylon Webbings Utilizing 840 Denier Yarns i n Lieu of Now-Specified 21 0 Denier Yarns . WADC-TR- 55-494, AD- 102826, May 1956

Bickford, H. J. ; e t a l . : The Development of High Strength Nylon Parachute Fab r i c s . WADC-TR-55-465, AD101948, May 1956


Sublette, R. A. : The Effect of Five Synthetic Lubricants on USAF F a b r i c s . WADC-TR-55-379, AD1 00696, May 1956

Bickford, H. J. ; et a l . : Development of Dacron Parachute Mater ia l s . WADG TR-55-432, Feb rua ry 1956

McCarthy, J. : Handbook of Pa rachu t c Tcxti le Mate r ia l s and P rope r t i e s . WADC-TR- 55-264, AD89171, F e b r u a r y 1956

McCrath , J. and Johnson, R. H. : The Ef fec t s of Gamma Radiation on Texti le Mate r ia l s . WADC-TR- 56- 15, AD92044, F e b r u a r y 1956

Krzywoblocki, M. Z . : Aerodynamic Studies: The F o r c e s Acting on an A i r Vehicle, A Review of the L i t e r a tu r e . WADC-TN-56-360

Lav rakas , V. and Katz, A. : The Effect of Surface F in i sh on Fr ic t ion and Fu- s ion of Parachute Cloth and Line. WADC-TR- 54-323, P a r t 2, December 1955

Block, L. C. : Aerodynamic Heating of Parachute Ribbons. WADC-TR- 54- 572, November 1955

Lavrakas , V. and Katz, A. : The Ef fec t of Surface Finishes on Fr ic t ion and Fusion of Parachute Cloth and Line. WADC-TR-54-323, P a r t 1 , AD91873, October 1955

Topping, A. D. ; Marke tos , J. D. ; and Costakos, N. C. : A Study of Canopy Shapes and S t r e s s e s fo r Parachutes in Steady Descent. WADC-TR-55-294, Goodyear A i r c r a f t Corporation, October 1955

Sweeney, J. W. : Evaluation of Antistat ic Agents on Nylon Parachute Cloth. WADC-TR- 54-513, September 1955

Lavrakas , V. : The Effect of Fab r i c S t ruc ture on the Fr ic t iona l Fusion of Parachute Mater ia l s . WADC -TR- 54- 570, AD90859, August 1955

X-7A Supersonic Ramjet Tes t Vehicle Parachute Recovery Sys tem Section Two - Recovery Sys tems . WADC-TR-55- 162, June 1955

Loptien, C. W. and Goodwin, M. D. : Wind Tunnel Tes t s of Full Scale G. P. 2000 and 3000 Pound Bombs Stabil ized with Parachutes . WADC-TN- 55- 167, May 1955

Nurse , J. W. , J r . , F i r s t Lt . , USAF: A Study of the Effect of Tempera tu r e on Parachute Texti le Mate r ia l s . WADC-TR- 54- 117, 1955

Bickford, H. J. ; Kuehl, D. K. ; and Rusk, T. L. : Study of the Control of Permeabi l i ty of Nylon Parachute Cloth a t High and Low Differential P r e s s u r e s . WADC-TR- 54-468, March 1955


Brown, C. D. : A Study of the Laws of the Flow of Fluids through F a b r i c s . WADC -TR-54- 199, January 1955

Graham, C. R. : 56-Ft Nominal Diamete r Parachute with 10 P e r c e n t Extended Skirt . Technical Note F T L 54-17, August 1954

McGrath, J. C. : Symposium on Parachute Text i les . WADC-TR- 54-49, AD- 4978, July 1954

Kiker , J. W. : B-47 Approach Control Parachute . WADC-TN- 54- 18, July 1954

Muse, J. W . , Jr. : A Study of the Effect of Tempera tu r e on Parachute Texti le Mate r ia l s . WADC -TR- 54- 11 7, AD55667, July 1954

Ecke r t , E . R. G. : Survey on Heat T r a n s f e r a t High Speeds. WADC-TR-54-70, Apr i l 1954

Daniels , L. E . , Capt. USAF: Effects of the Ups t r eam Influence of a Shock Wave a t Separated Boundary Laye r . WADC-TR-54-3 1, January 1954

Berndt , R. J. : F o r c e Distr ibution i n a Parachute Ha rnes s . TMR WCLE-53- 292, November 1953

Bickford, H. J. : Development of 0. 9 - 0 2 . Nylon Parachute Cloth. WADC-TR- 53-351, AD26850, September 1953

Ewing, E. G. : A Study to Es tab l i sh a Parachute Resea rch and Development P r o g r a m . Vol 111, Summary and Analysis of Existing Knowledge, WADC-TR- 53 - 78, AD1 10453, August 1953

Ewing, E . G. : A Study to Es tab l i sh a Parachute Resea rch and Development P r o g r a m . Vol 11, Summary and Analysis of Exist ing Knowledge, WADC-TR- 53-78, AD1 10452, August 1953

A Study t o Es tab l i sh a Parachute R e s e a r c h and Development P rog ram. Vol I, Bibliography and Collection of Ex t r ac t s , WADC-TR- 53-78, August 1953

Coplan, M. J. and Singer , E. : A Study of the Effect of Tempera tu r e on Tex- tile Mate r ia l s . WADC-TR-53-21, P a r t 2, July 1953

Coplan, M. J. : A Study of the Effect of Tempera tu r e on Texti le Mate r ia l s . WADC-TR 53-21, P a r t 1 , May 1953

Yoshihara, H. : On the Flow Over a Cone-Cylinder Body a t Mach Number One. WADC-TR- 52-295, 1952

Erdmann, S. : Drag Coefficients fo r Cones and Spheres a t Supersonic Speed. Cent ra l A i r Documents Office, Wright- Pa t t e r son AFB, (T rans . ) F-TS-4687- RE, F e b r u a r y 1948


111 - AEDC DOCUMENTS

De i t e r ing , J. S. and Hi l l i a rd , E . E . : Wind Tunne l Inves t iga t ion of F lex ib le Aerodynamic D e c e l e r a t o r C h a r a c t e r i s t i c s a t M a c h N u m b e r s 1. 5 to 6. AEDC- TR-65-110, June 1965

Dunkin, 0. L . and T r i m m e r , L . L . : Hyperson ic A e r o d y n a m i c C h a r a c t e r i s t i c s of Two El l ip t ic Hal f -Cones a t M Equa l s 8 and Angles of At t ack t o 90 D e g r e e s . 1 November 1963 - 1 Oc tober 1964, AEDC-TR-65-46 , AD458753

L i t t l e , H. R. : A e r o d y n a m i c F o r c e T e s t s of the A s s e t Re- e n t r y Configurat ion i n Tunnel F. X65-12386, J a n u a r y 1965

Jenke , L. M. and L u c a s , E. J. : Superson ic Wind Tunnel T e s t s of a P a r a c h u t e T e s t Sled. AEDC-TDR-64-203, AD448066, X65-10485, O c t o b e r 1964

Knapp, H. : G e m i n i Bal lu te S t r u c t u r a l T e s t a t M a c h N u m b e r s 0. 55 and 1. 92. AEDC-TDR-64- 131, June 1964

L o w r y , J. F. : A e r o d y n a m i c C h a r a c t e r i s t i c s of Var ious Types of F u l l Sca le P a r a c h u t e s a t Mach N u m b e r s f r o m 1 . 8 t o 3. 0. AEDC-TDR-64-120, June 1964

Be l l , D. R. : P r e s s u r e M e a s u r e m e n t s on the Rigid Model of a Balloon Decel - e r a t o r i n t h e Wake of a S imula ted M i s s i l e Pay load a t M a c h N u m b e r s 1 . 5 to 6 . AEDC-TDR-64-65, A p r i l 1964

De i t e r ing , J. S. : Wind Tunnel Inves t iga t ion of F lex ib le P a r a c h u t e Model C h a r a c t e r i s t i c s a t Mach N u m b e r s 1 . 5 t o 5. AEDC-TDR-63-263, J a n u a r y 1964

C l a r k , E. L. : Hyperson ic Stabi l i ty and P e r f o r m a n c e C h a r a c t e r i s t i c s of a F a m i l y of Modified Conoids (U). AEDC-TDR-64-20, J a n u a r y 1964 (CONFI- DENTIAL)

Riddle , C. D; and White, W. E . : An Inves t iga t ion of the Deployment C h a r a c - t e r i s t i c s and D r a g Ef fec t iveness of the G e m i n i P e r s o n n e l D e c e l e r a t o r a t Sub- son ic and Superson ic Speeds . P h a s e 11, AEDC-TDR-63-255, N64- 12073, De- c e m b e r 1963

Nichols , J. H. and Sib ley , G. 0. : An Inves t iga t ion of the Deployment C h a r a c - t e r i s t i c s and Drag Ef fec t iveness of the G e m i n i P e r s o n n e l D e c e l e r a t o r a t Sub- son ic and Superson ic Speeds . AEDC-TDR-63- 182, X63- 1473 1 , August 1963

De i t e r ing , J. S. : P e r f o r m a n c e of F lex ib le A e r o d y n a m i c D e c e l e r a t o r s a t Mach N u m b e r s f r o m 1. 5 t o 6. A E ~ c - ~ ~ R - 6 3 - 1 1 9 , Ju ly 1963


Gal igher , L. L. : Wind Tunnel T e s t s of the Kaman K R C - 6 ~ Rotochute a t Su- person ic Speeds. AEDC-TDR-63- 128, ~ 6 3 - 14209, July 1963

Deitering, J. S. : Per fo rmance of Flexible Parachute Models a t Mach Num- b e r s f r o m 1 . 5 to 4. AEDC-TDR-62-234, December 1962

The Drag of Spheres i n Raref ied Hypervelocity Flow. AEDC- TDR- 62- 205, December 1962

Deitering, J. S. : Investigation of Flexible Parachute Model Cha rac t e r i s t i c s a t Mach Numbers 1 . 5 to 6. AEDC-TDR-62-185, X63-13449, October 1962 (CONFIDENTIAL)

Br i l l ha r t , R. E . , Jr. and Donaldson, J. C. : F o r c e T e s t s of AVCO Re-en t ry Configurations a t Mach Numbers 2, 5, and 8. AEDC-TDR-62-92, N62- 12390, May 1962

Edenfield, E. E . : F o r c e Tes t s of Two ASD Blunt Liftin Bodies a t Mach Num- be r 19 (U). AEDC-TDR-62- 103, N- 110,059, May 1962 7 CONFIDENTIAL)

Kayser , L. D. : P r e s s u r e Distr ibution, Heat T r a n s f e r , and Drag T e s t s on the Goodyear Ballute a t Mach 10. AEDC-TDR-62-3 9, March 1962

Griffith, B. J. and Wolmy, W.: Sharp and Blunt Cone F o r c e T e s t s a t M of Approximately 17 and v a r i o u s ~ e ~ n o l d s Numbers . AEDC-TDR-62-67, March 1962

Wolmy, W.: Blunt Cone F o r c e T e s t s a t M = 20. AEDC-TDR-62-43, March 1962

Jones , J. H. and Deitering, J. S. : F o r c e and P r e s s u r e T e s t s on a Blunt Cone a t M a c h N u m b e r 8. AEDC-TDR-63-22, Feb rua ry 1962

Ward, L. K. and Urban, R. H. : Dynamic Stability T e s t s of Th ree Re-entry Configurations a t Mach 8. AEDC-TDR-62- 11, January 1962

Morgan, L. A. : Wind Tunnel Investigation of Flexible Parachute Models a t Supersonic Speeds. AEDC-TN-61-176, January 1962

Jones , J. H. and Deitering, J. S. : Force and P r e s s u r e Tes t s on a Blunt Cone a t Mach Numbers f r o m 2 to 5. AEDC-TN-61- 164, December 1961

B a e r , A. L. : P r e s s u r e Distr ibutions on a ' Hemisphere Cylinder a t Supersonic and Hypersonic Mach Numbers . AEDC- TN- 61 - 96, N63-82291, August 1961

Her ron , R. D. and Binion, T. W . , J r . : T e s t s of the Kaman KRC-6M Roto- chute a t Transonic Speeds. AEDC-TN-61-60, N-96964, May 1961


Ward, L. K. : Dynamic Tes t s on the AVCO Deployable Aerodynamic Dece le r - a t o r a t Supersonic and Hypersonic Speeds. AEDC-TN-61-30, AD252765, N- 98246, March 1961

Donaldson, J. C. : Stat ic Stabil i ty T e s t s on the AVCO Deployable Aerodynamic Dece le ra to r a t Supersonic and Hypersonic Speeds. AEDC-TN-60-209, AD246- 279, N-94179, November 1960

Coats , J. D. : Static and Dynamic Testing of Conical Trai l ing Dece le ra to rs fo r the Persh ing Re-en t ry Vehicle. AEDC-TN-60- 188, October 1960

Spring, D. J. : An Investigation of the Stat ic Stability and Axial-Force Charac- t e r i s t i c s of the AVCO Satell i te Drag Brake Sys tem a t Transonic Speeds. AEDC- TN-60-139, A ~ 2 4 0 3 6 7 , July 1960

Palko, R. L. : Aerodynamic Heating T e s t s a t Mach Number 5 of Nylon P a r a - chute Mater ia l Pro tec ted with Various Subliming Compounds. AEDC-TN-59- 41, AD214595, May 1959


IV - OTHER MILITARY DOCUMENTS

Gazley, C . , Jr. : Decelera t ion and Mass Change of a n Ablating Body during High-Velocity Motion i n the Atmosphere . Contract AF- 49/638/- 700, AD- 610287, N65-21100, January 1965

P e r s h , J. : Advanced Re- en t ry P r o g r a m s . Vol III-Summary, AD-3 5593 1, X65- 13792, December 1964 (SECRET)

P e r s h , J. : Advanced Re-en t ry P r o g r a m s . Vol I I -Mater ia ls and Sys tems Studies, AF-04/694/-486, X65-13791, December 1964 (SECRET)

Braun, W. F. : Growth of the Turbulent Inner Wake behind La rge Spheres a t Supersonic Velocities. BRL- MR- 1597, AD- 453850, N65- 15557, September 1964

Moulin, L. : Optimization of Recovery T ra j ec to r i e s fo r Space Vehicles, Final Scientific Report . AFOSR-64-2481, AD-609573, N65- 19305, Sep tember 1964

Reid, W. P. : Stability of a Towed Object. Mathematics Report M-52, NOLTR- 64- 116, AD-447154, N64-30595, October 1964

Za r in , N. A. : Wind Tunnel T e s t s of Rectangular Finned Variable Gap Tangent Ogive-Cylinder Model a t Mach Numbers 1 .75 to 4. 50. BRL-Memo- 1583, AD- 451304, N65- 11438, August 1964

Moulin, L. : A Poss ib le Compromise between Rocket and Atmospher ic Brak - ing, VK1-TN-17: AD-602391, N S ~ - 2 5 7 9 6 , June 1964

Caldwell, D. M. : Recovery of Lunar Vehicles - Geomet r ic Constra ints on T ra j ec to r i e s . F T C - T D R - ~ ~ - ~ 9, F e b r u a r y 1964

Gordon, H. C. and Hattendorf, G. A. : Flight Qualification of Ribless Guide Surface Drag Parachute to Produce Low Lift to Drag Ratios. FTC-TDR-63- 42, AD-429956, X64- 12660, F e b r u a r y 1964

Pres ton , C. R. , Jr. : Space Rendezvous, Rescue and Recovery, Comp. (An a b s t r a c t compilation. A r epo r t bibliography), N- 1 10- 91 1 , AD- 41 0085, August 1963

Jenkins, B. Z. : Real Gas Flow Field P rope r t i e s around Blunt Cones. Vol I, A r m y Miss i l e Command RF-TR-63- 18, August 1963


Spr ing , D. J. : T h e S ta t i c S tabi l i ty and D r a g of T h r e e Blunt- Cone R e - e n t r y Bodies a t M a c h N u m b e r s 15 and 18 (U). A M C - R F - T R - 6 3 - 1 7 , Ju ly 1963 (CONFIDENTIAL).

P e r s h , J. : Advanced R e - e n t r y P r o g r a m s . Vol I , S e m i - a n n u a l r e p o r t , AD- 337406, X65-10872, Ju ly 1963

Lehn, J. R. : A n t i - s u b m a r i n e W a r f a r e L a b o r a t o r y R e s e a r c h and Development P r o g r a m f o r A i r b o r n e Towed Vehic les . AD-296131, NADC-AW-6229, X65- 12494, J a n u a r y 1963

R e i s s , M. : Measur ing t h e Coefficient of D r a g of a n A c c e l e r o m e t e r - I n s t r u - m e n t e d S p h e r e in a Shock Tube. NOLTR-62- 162, N62- 17007, August 1962

Ehni , F. P.; and Ha ldeman , W. F. : Study of Soft R e c o v e r y f r o m Two- s t a g e Vehic les . P a r t 11: V e r t i c a l D e s c e n t T r a j e c t o r i e s Including A e r o d y n a m i c Heat- ing, N62-13823, May 1962

F r e e d , A. : Newtonian Drag Coeff ic ients and Weights f o r Blunted Cone S p h e r e s a t S m a l l Angles of At tack . MIT, Lincoln L a b . , A F E S D TDR 62-81 (Repor t No. 220 -5 ) , M a r c h 1962

Schwider sk i , E . W. : Singu la r i t i e s in S u p e r s o n i c F lows p a s t Bod ies of Revolu- tion. N62- 11837, F e b r u a r y 1962

S c h u r r , G. G. : Study of Soft R e c o v e r y f r o m Two-Stage Vehic les . AFOSR- DRA-62-2 N62- 11 959, J a n u a r y 1962

NavWeps R e p o r t 1488 (Vol 3 ) : Handbook of Super son ic A e r o d y n a m i c s . Sect ion 8 , Bod ies of Revolut ion, Oc tober 1961

F a u c h e r , G. A. ; P r o c u n i e r , R. W. ; and S t a r k , C . N. : Fl igh t In fo rmat ion a n d E x p e r i m e n t a l R e s u l t s of Inf la table Fa l l ing S p h e r e S y s t e m f o r M e a s u r i n g Upper A i r Densi ty . USAF, Geophys ics R e s e a r c h D i r e c t o r a t e , GRD R e s e a r c h Notes No. 6 3 , A F C R L 685, AD-265172, August 1961

Hayes , J. E.; and Vander Velde , W. E. : A Sa te l l i t e Landing Contro l Sys tern Utilizing D r a g Modulation. AD- 603 134, N64-85802, August 1961

B i x l e r , D. N.; and G a t e s , D. F. : F o r c e a n d Moment M e a s u r e m e n t s of Models of the ARGMA Conf igura t ion in the NOL 4-In. Hyperson ic Shock Tunnel No. 3. NOLTR h 1 - 96, N- 106- 467, August 196 1

Knacke , T . W. ; P a u l s o n , K. R. ; and S c h u r r , G. G . : Study of Soft Recovery . Techn ica l Repor t , AFOSR- 104, N62- 13 153, M a r c h 196 1

Haak, E . L. ; Heinr i ch , H. G. ; I b r a h i m , S. K. ; Niccum, R. J. ; and Riabokin, T . : T h e o r e t i c a l P a r a c h u t e Inves t iga t ions P r o g r e s s Repor t . AD- 605143, N65- 80441, 1961


Masson, D. J. ; M o r r i s , D. N. ; and Bloxsom, D. E. : Measurements of Sphere Drag f r o m Hypersonic Continuum to Free-Molecu le Flow. USAF, P r o j e c t Rand R e s e a r c h Memorandum TM-2678, The Rand Corporat ion, 3 November 1960

Be rge r , S. A. : Hypersonic Flow over Cones. AFOSR TN 60-1214, Sep tember 1960

Downing, Dr. J. R. ; Hawkins, Dr . H. V. ; McClow, P. W. , Jr. ; and P e t e r - sen, P. E. : Recovery Sys tcms for Miss i l es and T a r g e t Ai rc ra f t . A F Tech-

nlcal Repor t 5853

T ra j ec to ry Study of Parachute T e s t Vehicles. AD-243876, A F F T C TR 60-37, N-93096, July 1960

Beeding, E. L . , J r . : Daisy Dece le ra to r T e s t s . Run number 520-707, N64- 81247, July 1960

S ims , J. L. : Supersonic Flow around Right Ci rcu la r Cones - Tables fo r Z e r o Angle of Attack. ABMA Report DA-TR-11-60

S ims , J. L. : Supersonic Flow around Right C i r cu l a r Cones - Tables fo r Smal l Angle of Attack. ABMA Report DA-TR-19-60, Apr i l 1960

Musil , J. L. : Requirements and Considerat ions f o r Test ing Hypersonic Re- tardat ion Devices fo r Re-en t ry Vehicle Recovery. A F F T C TR 59-4, March 1959

F r e e m a n , H. F.; and Rosenberg, C. : High Altitude and High Ai rspeed T e s t s of Standard Parachute Canopies. AFFTC- TR- 58-32, AD- 152286, October 1958

Kahl, G. D. : Supersonic Drag and B a s e P r e s s u r e of a 70-Degree Cone Cylin- de r . BRL Memo Report 1178, N-68696, November 1958

Aerodynamic Heating of Parachutes . SN- 52823

Recovery Sys tems f o r Miss i l es and Ta rge t Ai rc ra f t . SN-45004

Fel ix , A. R. : F o r c e T e s t s of a Rela ted Fami ly of Twenty Nose Cones for a Range of Mach Numbers f r o m 0.47 to 1.93. ABMA Repor t DA-TN-42-58, July 1958

Marks , A. S. : Normal F o r c e , Pitching Moment, and Cente r of P r e s s u r e of Seve ra l Spher ical ly Blunted Cones a t Mach Numbers of 1. 50, 2. 10 and 4. 04. US AOMC-ARGMA-OML Repor t 6R8F, Apr i l 1958

Katz, J. R. : P r e s s u r e and Wave Drag Coefficients fo r Hemispheres , Hemis- phere- Cones, and Hemisphere-Ogives. Naval Ordnance T e s t Station, NavOrd Report 5849, M a r c h 1958


Lehner t , R.; and Sche rmerho rn , V. L. : Wake Investigation on Sharp and Blunt Nose Cones a t Supersonic Speeds. NavOrd Report 5668, U. S. Naval Ordnance Lab. , January 1958

Re-en t ry Studies. Vol 1 , Army Bal l is t ic Miss i l e Agency, X63 - 8 2 2 11, Novem- be r 1958.

Recovery Sys tems for Miss i l es and Ta rge t Ai rc ra f t . A F Technical Report 5853, P a r t I , March 1954, P a r t 111, December 1956

May, A. : Supersonic Drag of Spheres a t Low Reynolds Numbers in F r e e Flight. NavOrd Report 4392, Aerobal l is t ic Resea rch Report 3 56, N-49669, December 1956

Sabin, C. M. : The Effects of Reynolds Number , Mach Number , Spin Rate , and Other Var iables on the Aerodynamics of Spheres a t Subsonic and Transonic Ve- locit ies. Memorandum Report No. 1044, Bal l is t ic Resea rch Lab. , November 1956

Mart in , G. E . : Aerodynamic Phenomena f o r Bodies of Revolution in Super- sonic Motion. NAFI T P - 7 , N-53536, September 1956

Liccini , L. L o : Hypersonic Tunnel No. 4 Resul ts IX: The Development of a Water - Cooled Stra in-Gage Balance (Including Sting Effects) and i t s Application to a Study of Normal F o r c e and Pitching Moments of a Cone and Cone-Cylinder a t Mach Numbers 5 to 8. NavOrd Report 4334, U. S. Naval Ordnance Lab. , August 1956

Deep, R. PI.; and Henderson, J. H. : Study of Aerodynamic Charac te r i s t i cs of Cone-Cylinder-Conical F r u s t u m Bodies by Linear ized Theory of Supersonic Flow. Ordnance Miss i l e Lab . , Report 6R2P, 8 June 1955

Downing, Dr . J. R. ; McClow, J. H. J r . ; Hawkins, Dr . H. V. ; and F rede t t e , R. 0. : Recovery Sys tems for Miss i l es and Ta rge t A i r c r a f t , Subsonic F r e e Flight Validation T e s t Phase . A F TR 5853 P a r t 11, March 1955

Dickinson, E. R. : Some Aerodynamic Effects of Head Shape Variat ion a t Mach Number 2. 44. BRL Memo Repor t 838, N-35758, October 1954

Buford, W. E. : Magnus Effect i n the Case of Rotating Cylinders and Shell. BRLM 82 1 , July 1954

S t imle r , F. S.; and Ross , R. S. : Drop T e s t s of 16, 000 Sq In . , Model P a r a - chutes. Vol VIII, A F TR 5867, May 1954

Downing, J. R. ; Areson , D. L. ; and McClow, J. H . , J r . : Recovery Sys tems f o r Miss i l es and Ta rge t Ai rc ra f t . Subsonic Sled T e s t Phase , A F TR 5853, P a r t I , March 1954


Buford, W. E.; and Shatunoft, S. : The Effects of F ineness Ratio and Mach Number on the Norma l F o r c e and Cente r of P r e s s u r e of Conical and Ogival Head Bodies. BRL Memo Report No. 760, F e b r u a r y 1954

Schmidt, L . E. : The Dynamic P r o p e r t i e s of P u r e Cones and Cone Cylinders. BRL-MR-759, January 1954

Cone Sta t ic Stabil i ty Investigation a t Mach Numbers 1. 56 through 4.24. NavOrd Report 3584, AD-28203, 7 December 1953

Shantz, I. : Cone Sta t ic Stability Investigation a t Mach Numbers 1. 56 through 4.24. NavOrd Report 3584, December 1953

Lene r t , R. : Base P r e s s u r e of Spheres a t Supersonic Speeds. NavOrd Repor t 2774, F e b r u a r y 1953

Heinrich, H. G. : Experimental P a r a m e t e r s in Parachute Opening Shock Theory. Shock and Vibration Bullet in No. 19. Resea rch and Development Board , Dept. of Defense, AD-9513, F e b r u a r y 1953

Murphy, C. H.; and Schmidt, L. E. : The Effect of Varying Length on the Aero- dynamic Cha rac t e r i s t i c s of Bodies of Revolution in Supersonic Flight . BRL Report 876, 1953

May, A.; and Witt, W. R. , Jr. : F r e e Flight Determinations of the Drag Coef- f icient of Spheres . NavOrd Report 2352, August 1952

Beasta l l , D.; and T u r n e r , J. : The Effect of a Spike Protruding in F ron t of a Bluff Body a t Supersonic Speeds. ARC R and M 3007, January 1952

Weinig, F. S. : On the Dynamics of the Opening Shock of a Parachute . USAF Office of Aeronaut ical Resea rch . TR 6 , 1951

Heinrich, H. G. : Aerodynamics , Pe r fo rmance and Design of Pe r sonne l Guide Parachute . Memorandum Report No. WCEE-672- 145-A-9- 1, November 1951

Hoerner , So : Drag Charac te r i s t i cs of Parachutes . USAF AFTR 6201, ATI- 92530, October 1950

T e s t and Evaluation of 24-F t Hemispher ica l Baseba l l Parachute . Report No. 5028- 49- 2, U. S. Naval Parachute Exper imenta l Unit, Naval A i r Station, E l Centro, Calif.

Tes t and Evaluation of Hemispher ica l Baseba l l Retarding Parachutes . Repor t No. 5018-49-4, U. S. Naval Parachute Exper imenta l Unit, Naval A i r Station, E l Centro, Calif.

USAF Handbook AT1 No. 35532, Apr i l 1947 ( r ev i s ed March 1951)


Clippinger, R. F. ; Giese , J. H. ; and C a r t e r , W. C. : Tables of Supersonic Flows about Cone Cylinders. P a r t I: Surface Data, Report No. 729, Bal l is t ic Resea rch Labs . , July 1950

Buhler , W. C. : Parachute Airfoi l Type, Pe r fo rmance of. Memorandum Re- po r t No. MCREXE-672- 19T, January 1949

Knacke, T.; and Hegele, A. : Model Pa rachu t e s , Comparison Tes t s of Various Types. Memorandum Report MCREXE-672- 12B, January 1949

Buhler , W. C. : Poros i ty , Effect of, on Pa rachu t e Opening. MCREXE-672- ZA, December 1948

Knacke, T. : FIST Type Parachute , Design, Use and Construction of. Memo- randum Repor t No. MCREXE-672- 19LL, June 1948

Heinrich, H. G. : Parachu te s , Guide Surface. Memorandum Report No. MCREXE-672-25F, AT1 No. 28935, F e b r u a r y 1948

Buford, W. : Comparison of the Theore t ica l Aerodynamic Cha rac t e r i s t i c s of a Se r i e s of Cones with the Resul ts Found by Supersonic Wind Tunnel Exper i - men t s . SSWTL Memorandum to D i r ec to r , BRL 23, 1948

Weinig, F. S. : Parachutes with Canopies Composed of Self-Supporting Rib- bons. USAF Trans la t ion of Ge rman Report F-TR-2148-ND, AT1 25818, O c - tober 1947

Knacke, T. : Reefing Methods, Parachute . TSEPE 672-25D, October 1947

H a r r i s , P. : Separat ion of Shock Wave f r o m the Nose of a 40-Degree Cone. BRL 651, 1947

Ecker t , E. : Calculation of the T e m p e r a t u r e which a Parachute Canopy Attains a t High Altitude. AMC TR F- TR-2133 -WD, December 1946

Kane, E. D. : Sphere Drag Data a t Supersonic Speeds and Low Reynolds Num- b e r . BRL 514 TN 4125, January 1945

Von Karman, T. : Note on Analysis of the Opening Shock of Parachutes a t Var i - ous Altitudes. A r m y Ai r Corps Scientific Advisory Group, 1945

Henn: Des cent Charac te r i s t i cs of Pa rachu t e s . USAF Trans la t ion of Ge rman Report Z W B / W M / ~ ~ O ~ , October 1944

Hallenbeck, G. A. : The Mgnitude and Duration of Parachute Opening Shocks a t Various Altitudes and A i r Speeds. A F MR ENG 49-696-66, 1944


Heinrich, H. G. : Investigation of the Stabil i ty of Pa rachu t e s in the Develop- men t of a Stable Pa rachu t e Manufactured of P e r m e a b l e Mater ia l . USAF T r a n s - lation of G e r m a n Report No. 300, MTI 42978, M a r c h 1943

Duncan, W. J. : The Cause of the Spontaneous Opening and Closing of Para- chutes. ARC RM No. 2 11 9, 1943

Heinrich, H. G.; and Gerha rd , R. : Wind Tunnel T e s t s of Parachutes . USAF Trans la t ion of Ge rman Repor t FGZ 192, AT1 23380, March 1942

Doets ch, H. : Three - C omponent Measurements of Pa rachu t e Canopies of Dif - fe ren t Shapes. USAF Trans la t ion of Ge rman Repor t F B 229, F e b r u a r y 1935

Mil ler , Lt. A. P. : The David Taylor Model Basin. Dept. of the Navy

Whicker, E.; and Lum, F. : Stabil i ty, Strength, and Opening Cha rac t e r i s t i c s of Parachutes i n Water . David Taylor Model Basin , Dept. of the Navy


Keck, J. C . : R e s e a r c h in R e - e n t r y P h y s i c s , F i n a l T e c h n i c a l S u m m a r y Re- p o r t , AVCO-Evere t t R e s e a r c h Lab . , DA- 19-020-AMC-0210, AD-357619, X65- 15161, M a r c h 1965

G r a h a m , J. J. : Inf la table F l a r e Stabi l iza t ion Device f o r ALARR - Des ign and Development , GER- 11 51 1, Goodyear A e r o s p a c e C o r p o r a t i o n , Akron , Ohio, F e b r u a r y 1965

R e s u l t s of incomple te unpubl ished GAC In-House d r o p t e s t p r o g r a m

R e s u l t s of unpublished Snakeye I1 (NOTS funded) ana ly t i ca l and t e s t s tudy p r o - g r a m

B a r s h , M. K. ; B a r t o n , C. J. ; Kevi l le , J. F. ; Tomkinson , S . L. : S e m i - Rigid S t r u c t u r e s f o r R e - e n t r y Appl ica t ions - Seventh I n t e r i m Eng inee r ing P r o g - r e s s Repor t . Space G e n e r a l C o r p . , SGC-335-23, I R - 7 - 9 4 3 ~ / ~ 1 1 , X65- 12481, D e c e m b e r 1964

Klet t , R . D. : D r a g Coefficients and Heating Ra t ios f o r Right C i r c u l a r Cylin- d e r s i n F r e e - M o l e c u l a r and Cont inuum F low f r o m Mach 10 to 30. Sandia C o r p . , SC-RR-64-2141, N65-24226, D e c e m b e r 1964

GAC M e m o r a n d u m , ARD- 7538, da ted D e c e m b e r 30 1964, en t i t led E s t i m a t e of Bal lu te Weight

GAP-1997, ~ / 3 : P r o p o s a l f o r Irrlproved D a t a - R e c o r d e r R e c o v e r y S y s t e m , Goodyear A e r o s p a c e C o r p o r a t i o n , A k r o n , Ohio, 15 D e c e m b e r 1964

A h a r t , A . P. : S t r e s s Ana lys i s - G e m i n i Bal lu te S y s t e m GA526, G E R - 11 936, Goodyear A e r o s p a c e C o r p o r a t i o n , Akron , Ohio, i n p r e s s

Inves t iga t ion of R e c o v e r y Tecn iques Appl icable to the T e r m i n a l P o r t i o n of the Sle igh Ride MK-12 R/V Descen t T r a j e c t o r y (unc las s i f i ed t i t l e ) , Goodyear A e r o - s p a c e Corpora t ion , GER- 11826, N o v e m b e r 1964 (SECRET) .

N e r e m , R. M. : An A p p r o x i m a t e Method f o r Including the Effec t of the Inviscid Wake on the P r e s s u r e Dis t r ibu t ion on a Bal lu te Type D e c e l e r a t o r , GER- 11 824, Goodyear A e r o s p a c e C o r p o r a t i o n , Akron , Ohio, N o v e m b e r 1964

N e r e m , R. M. : Superson ic Wake Phenomena wi th Appl ica t ion to Bal lu te- Type D e c e l e r a t o r s , GER- 11820, Goodyear A e r o s p a c e Corpora t ion , Akron , Ohio, November 1964


GER- 11806: Aerodynamic Deployable Dece le ra to r Pe r fo rmance Evaluation P r o g r a m , Parachute T e s t I t ems L P - 3 and L P - 4 , Goodyear Aerospace Cor - poration, Akron, Ohio, 30 November 1964

GAP-2974: P roposa l f o r Aerodynamic Deployable Dece le ra to r Pe r fo rmance Evaluation P r o g r a m - P h a s e 111, Goodyear Aerospacc Corporat ion, Akron, Ohio, 23 November 1964

GER- 11672, ~ / 1 : Aerodynamic Deployable Dece le ra to r Pe r fo rmance Evalu- at ion P r o g r a m (ADDPEP), Goodyear Aerospace Corporat ion, Akron, Ohio, October 1964

GAP-2849: P roposa l f o r Recovery Sys tem for the Mart in-Marie t ta Corpor - ation. Goodyear Aerospace Corporation, Akron, Ohio, 9 Sep tember 1964

Schneider, J. ; Schus te r , L. ; Visich, M . , J r . : Additional Aerodynamic Cha rac t e r i s t i c s of a Canted- Cone Re- en t ry Body a t Hypersonic Velocit ies. Genera l Applied Science Labs . , Inc. , TR-465, AD-352910, X65- 11495, July 1964 (SECRET).

Oberg, A. J. : An Engineering Design Study and T e s t P r o g r a m for the P a r a - vulcoon Recovery Sys tem Monthly P r o g r e s s Le t t e r Number VIII. Minneapolis- Honeywell Regulator Co . , N64-82087, March 1964.

GAP- 248 5: NASA High-Speed Decelera t ion Sys t e m Proposa l , Vol 1. Goodyear Aerospace Corporation, Akron, Ohio, 6 F e b r u a r y 1964

GAP-2456: P roposa l fo r Aerodynamic Deployable Dece le ra to r Pe r fo rmance Evaluation P r o g r a m - P h a s e 11. Goodyear Aerospace Corporat ion, Akron, Ohio, 5 F e b r u a r y 1964

Ellet t , D. M. : P r e s s u r e Distr ibutions on Sphere Cones. Sandia Corp. , N65- 14813, January 1964

Cloud, J. B.; and Lindell , L. K. : Resea rch on Method for Production of Therrnat ic S t ruc tura l and/or Heat Shielding Mater ia l s . Phase I1 - P r o c e s s Development and T r i a l Production. IR-8- 1 17/11, AD- 440279, 1964

Nerem, R. : Hypersonic Aerodynamic Heating, GER- 11482, Goodyear Aero- space Corporat ion, Akron, Ohio, 3 1 January 1964

GER- 11 138, ~ / 7 : ADDPEP Monthly P r o g r e s s Report No. 8. Goodyear Aero- space Corporat ion, Akron, Ohio, January 1964

GER- 11 41 5: Analysis and Design of Hyperflo T e s t I t e m S P - 5 (ADDPEP). Goodyear Aerospace Corporation, Akron, Ohio 15 January 1964 (CONFI- DENTIAL).


G E R - 11 138, ~ / 6 : A e r o d y n a m i c Deployable D e c e l e r a t o r P e r f o r m a n c e Evalu- a t ion P r o g r a m - Monthly P r o g r e s s R e p o r t No. 7. Goodyear A e r o s p a c e C o r - po ra t ion , Akron , Ohio, 8 D e c e m b e r 1963

G E R - 113 19: P r e l i m i n a r y Des ign R e p o r t of a n Inf la table Stabi l iza t ion S k i r t , Goodyear A e r o s p a c e Corp . , Akron , Ohio, November 1963 (CONFIDENTIAL).

G E R - 11279: Ana lys i s and Des ign of Ba l lu te T e s t I t e m B- 1 ( A D D P E P ) . Good- y e a r A e r o s p a c e Corpora t ion , Akron , Ohio, 10 O c t o b e r 1963

Gebhard t , J. E . and S h e e t e r , H. H. : S e r i e s I1 T e s t P r o g r a m on Fu l l -Sca le G e m i n i A s t r o n a u t Bal lu te in AEDC S u p e r s o n i c P r o p u l s i o n Wind Tunnel , G E R - 11276, Goodyear A e r o s p a c e C o r p o r a t i o n , Akron , Ohio, O c t o b e r 1963

Drawing 530A002-001: Vehic le A s s e m b l y - Capabi l i ty C. C o n t r a c t A F - 3 3 (657)- 10955, 11 Oc tober 1963

G r o s s , F. R. : O r b i t a l R e c o v e r y wi th Expandable P r e s s u r i z e d Drag Bod ies , G E R - 11 124, Goodyear A e r o s p a c e Corpora t ion , Akron , Ohio, 1 Ju ly 1963

G E R - 10772: P a r a m e t r i c Study of O r b i t a l R e c o v e r y wi th Expandable D r a g Bod ies . Goodyear A e r o s p a c e C o r p o r a t i o n , 1962

Reding, J. P. : S e p a r a t e d F low Ef fec t s on t h e S ta t i c S tabi l i ty of Cone-Cyl inde r Flare Bodies . Lockheed M i s s i l e and Space CO. , LMSC-802336, X63-15817, 1962 (CONFIDENTIAL).

Space Vehic le R e c o v e r y C o n t r o l S y s t e m Concepts . Raytheon Co. , Equipment D i v . , ~ 6 3 - 1 7 9 6 7 , 1962

GER-10923: Nova B o o s t e r R e c o v e r y S y s t e m Study. Goodyear A e r o s p a c e C o r - po ra t ion , Akron , Ohio, 21 D e c e m b e r 1962

F r a n c i s , W. L. and Whi te , C. 0. : Study of Hyperson ic F low F i e l d s a n d A e r o - dynamic F o r c e s on S h a r p Cones a t Angle of At t ack i n Low-Densi ty Flow. Re- e n t r y S y s t e m s P r o g r a m , Aeronu t ron ic , AD- 400946, N65-80443, November 1962

McCauley , W. D. : Low Dens i ty Hyperson ic S i m i l a r i t y of Cones and Slight ly Blunted S p h e r e Cones . G e n e r a l E l e c t r i c C o . , M i s s i l e and Space Vehic le D e p t . , Vol V, X63-11325 ( S E C R E T ) .

G A P - 1706: P r o p o s a l f o r A e r o d y n a m i c Deployable D e c e l e r a t o r P e r f o r m a n c e Evaluat ion P r o g r a m - P h a s e I. Goodyear A e r o s p a c e C o r p o r a t i o n , Akron , Ohio, 24 Oc tober 1962.

A e b i s c h e r , A . C. : F r e e - F l igh t D r o p Tes t ing of t h e Apollo E a r t h Landing Sys- t e m , Goodyear A e r o s p a c e C o r p o r a t i o n , Akron , Ohio, GAP- 1622, 20 August 1962


N- 114,601: Genera l E l ec t r i c Co. , R62SD63

Br iggs , J. L.; and Marsha l l , L. A. : Pred ic t ion of Aerodynamic Coefficients (U). August 1962 (CONFIDENTIAL).

Aebischer , A. C. : Ballute Stabil ization and Decelera t ion Sys tem l o r Erner - gency Recovery of a Gemini Astronaut. Goodyear Aerospace Corporat ion, Akron, Ohio, enc losure to GAC L e t t e r X49-F9982, 19 August 1962

Weber , H. E. and Pugmi re , T. K. : Miss i le and Space Vehicle Dept. , Genera l E l ec t r i c Co. , ARC Resea rch Studies, X62- 1063 5, August 1962 (CONFIDENTIAL).

Kat tner , W. T. : A Bibliography of Bibliographies Relating to Re-en t ry P rob - l ems . Genera l ~ ~ n a m i c s / ~ o r t . Worth, ERR-FW- 153, AD284,363, N- 110,755, July 1962

Houtz, N. E . : The Application of Isotensoid Membranes to the Design of In- f latable Drag Bodies. Goodyear Aerospace co rpo ra t i on , GER- 10770, 3 1 July 1962

Aebischer , A. C. : Development of an Expandable S t ruc ture fo r High Effective A r e a Rocket Nozzles. Goodyear Aerospace Corporat ion, Akron, Ohio, GAP- 1444, 13 July 1962

Karaffa, N. T. : High-Density Disk Samples , Deployment and Ballute Recov- e r y , Description. Goodyear Aerospace Corporat ion, Akron, Ohio, GER-10753, 15 June 1962

GER- 10729: An Approximate Method for Establishing Recovery Sys tem Design Cr i te r ia . Goodyear Aerospace Corporat ion, Akron, Ohio, 8 June 1962

Exper imental Investigation of the Aerodynamic Cha rac t e r i s t ics of 40 Degree Half-Angle Cones with Varying Degrees of Bluntness a t Mach Number 9. Aero- nutronic, A Division of F o r d Motor Company, AERON-U- 1638, Apr i l 1962

Nebiker, F. R. : Resea rch and Development of a n Expandable S t ruc ture Type Decelera t ion and Stabil ization for u s e in the Mach 10 Flight Regime. Goodyear Aerospace Corporat ion, GER- 10668, 20 Apr i l 1962

Aebischer , A. C. : Design T e s t Ha rnes s and Field T e s t S te l l a r Guidance Sys- tem. Goodyear Aerospace Corporat ion, Akron, Ohio, GAP- 13 78, 3 Apr i l 1962

Hritzay, D.; and Wiant, R. : Wire Cloth S t ruc ture fo r a Radiating Re- en t ry Vehicle, AVCO-Everett R e s e a r c h Lab . , N62- 11813, March 1962

Optimum Staging for A r b i t r a r y Boost T ra j ec to r i e s . DODCO TR-117, March 1962


GER- 10614: A G e n e r a l S ix -Degrees -o f - F r e e d o m T r a j e c t o r y Model f o r a n IBM- 141 0 Digital Computer . Goodyear A e r o s p a c e Corpora t ion , Akron, Ohio, 20 M a r c h 1962

Aebischer , A. C. : Dece le ra t ion and Stabil izat ion S y s t e m for Sandia Corpor - a t ion Sand- Lo P r o g r a m . Goodyear A e r o s p a c e Corpora t ion , Akron, Ohio, GAP-1323, 20 M a r c h 1962

E ther ton , B. D. ; B u r n s , F. T . ; Nooman, L. C. : E s c a p e Capsule Stabil izat ion P a r a c h u t e S y s t e m Development. G e n e r a l ~ ~ n a r n i c s / ~ o r t Worth , X63 - 1452 1 , F e b r u a r y 1962

GAP- 1258 : P r o p o s a l f o r the Development of S t r u c t u r a l Design C r i t e r i a f o r Recovery of A e r o s p a c e Vehic les and B o o s t e r s . Goodyear A e r o s p a c e C o r p o r - a t ion , Akron, Ohio, 16 J a n u a r y 1962

Deployable Aerodynamic D e c e l e r a t o r s : A L i t e r a t u r e Survey , Compiled by L i t e r a t u r e R e s e a r c h Group. A e r o s p a c e L i b r a r y , A e r o s p a c e Corpora t ion , TDR-930(2701-01) TN-2, November 1961

GER-10465: S t r e s s Analys is of the Tra i l ing Drag Body Wind Tunnel Models f o r the Langley Uni tary P l a n Wind Tunnel , Second S e r i e s of T e s t s . Goodyear A e r o s p a c e Corporat ion, Repor t , 2 November 1961

AAD-408: F o u r - D e g r e e s - of- F r e e d o m Equations of Motion fo r R e - E n t r y Ve- h ic les . 18 October 1961

Karaffa , N. T . : Raytheon Decay Miss i l e Inflatable D e c e l e r a t o r . Goodyear A e r o s p a c e Corporat ion, Akron , Ohio, GER- 1041 7 , 26 Sep tember 196 1 (SECRET).

GAP- 1040: P r o p o s a l f o r Recovery of M i s s i l e o r Sa te l l i t e -Borne Radioactive Components. ~ o o d ~ e a r ~ e r o s ~ a c k Corporat ion, Akron, Ohio, 20 Septernbe r 1961

GER- 1041 2: A Fabr ica t ion and M a t e r i a l Repor t on Expandable S t r u c t u r e Re- e n t r y Drag Cones f o r the Douglas A i r c r a f t Company, Inc. Goodyear A e r o s p a c e Corporat ion, Akron, Ohio, 20 Sep tember 1961

GAP- 9992: P r o p o s a l f o r Design and Fabr ica t ion of P e r s h i n g G and C Unit Re- covery Sys tem. Goodyear A e r o s p a c e Corpora t ion , Akron, Ohio, 16 August 196 1

Gebhardt , J. E. : Design and Fabr ica t ion of P e r s h i n g Miss i l e Recovery Sys- t e m . Goodyear A e r o s p a c e Corpora t ion , Akron, Ohio, 12 June 1961

GAP-9848: Piggyback Ballute O r b i t Decay Recovery P r o g r a m . Goodyear A e r o s p a c e Corporat ion, Akron , Ohio, 12 June 1961


Be l t r am, A. A. : Aerodynamics of Cones and Pro tuberances . Lockheed Mis- s i l es and Space Division Lockheed A i r c r a f t Corporat ion, Specia l Bibliography 3-30-61-1-SB-51-28, May 1961

Kuly, P. W. : P r e Tes t Report , Transonic and Supersonic Wind Tunnel T e s t s of Drag Bodies fo r the P r o j e c t 726 8 P e r c e n t Scale Model Re-en t ry Vehicle a t NASA. Langley Fie ld , N-97325, May 1961, ER 11801

F rede t t e , R. 0. : Parachute R e s e a r c h Above Cr i t i ca l Aerodynamic Velocities. Unpublished r epo r t of Cook Resea rch L a b . , May 1961

GAP-9794: P roposa l fo r Development and Fabr ica t ion of Iner t i a l Guidance T e s t Container and Recovery System. Goodyear Aerospace Corporat ion, Akron, Ohio, 15 May 1961

GER- 10241: Reliabil i ty a t Goodyear A i r c r a f t Corporation. Goodyear Aero- space Corporation, Akron, Ohio, 15 Apr i l 1961

ARD-876: P re l im ina ry Investigation of Metal F a b r i c Re -En t ry Drag Bodies. Goodyear Aerospace Corporation, 22 F e b r u a r y 1961

Nebiker, F. R. : An Inflatable Balloon-Type Decelera t ion and Stabil ization Sys tem fo r Recovery of Space Vehicles. Goodyear Aerospace Corporation, Akron, Ohio, GER-9774, Rev. A., 23 January 1961

An Inflatable Balloon - Type Decelera t ion and Stabilization Sys tem for Recov- e r y of Space Vehicles. GER-9774, Rev. A, Goodyear Aerospace Corporation, January 196 1

GER- 10239: Study of Inflatable Balloon Type Drag Devices fo r Mach 10 Flight Regime. Goodyear Aerospace Corporation, Akron, Ohio, 196 1

Ewing, E. G. : Ringsail Parachute Charac te r i s t i cs . Radioplane Report No. PTM-323-A, January 1961

GAP- 951 7: Inflatable Balloon- Type Drag Devices fo r Mach 10 Regime. Good- y e a r Aerospace Corporation, Akron, Ohio, 13 December 1960, Rev. A

Supersonic T e s t s Conducted a t the Cook Technological Cente r Wind Tunnel on Parachute Type Decelera tor Models. Cook R e s e a r c h L a b . , October 1960, Unpublished r epo r t .

GAP-9270: P roposa l f o r Sa turn Boos te r Recovery System. Goodyear Aero- space Corporation, Akron, Ohio, 9 September 1960

Boos te r Recovery Study. Aero je t -Genera l Corporat ion, Report No. 18 16, July 1960


GER- 9827: Astronaut ics Handbook. Goodyear Aerospace Corporat ion, Akron, Ohio, 13 June 1960

S t imle r , F.; and Ross , R. : Drop Tes t s of 16, 000-Sq-In Model Parachutes . AFTR-5867, Vol 8 , Apr i l 1960

GER-8978: Monthly P r o g r e s s Reports on AF33 (6 16)- 601 0 Drag Balloon Study P r o g r a m . Goodyear Aerospace Corporation, Akron, Ohio, Rev. A through S, 6 August 1958 to 15 Apr i l 1960

S t o r e r , E. M. : Zero-Li f t Forebody Drag Coefficients f o r Various Sphere Cone Configurations a t Mach Numbers of 3. 5 to 25. Gene ra l E l ec t r i c C o . , Miss i l e and Space Vehicle Dept . , N63-81739, (Aerodynamics Data Memo No. 1 :19), March 1960

Landberg, S. R. : Densit ies of the Upper Atmosphere Derived f r o m Discovere r Sate l l i tes . Lockheed Miss i l es and Space Division, Sunnyvale, Calif. , March 1960

Kane, M. T. : T e s t Resul ts of the F i r s t Two Supersonic Parachute T e s t Ve- hicle F i r ings . Sandia Corporat ion Report SCTM 329- 59(51), 15 October 1959

GAP- 693 8S7: Proposed Balloon Stabil ization and Decelera t ion Sys t e m for Manned Orb i ta l Re- en t ry Vehicles. (P ro j . Mercury) . Goodyear A i r c r a f t Corporat ion, Akron, Ohio, CN- 76547, 29 September 1959.

AAD-2 14: Drag and P r e s s u r e Distr ibution Coefficients of Spheres , Spike Spheres , and Spheres in the Wake of Various Bodies a t Mach Numbers of 1. 5 , 2. 0 and 2 . 5 and Dynamic Stabil i ty of Te thered Spheres and Balloons. Goodyear Aerospace Corporat ion, Sep tember 1959

Detra , R. W. ; Kantrowitz, A. R . ; Riddell, F. R . ; and Rose , P. H . : Drag Brake for Manned Satell i te Recovery. AVCO C o r p . , CN-72149, Prepr in ted f r o m Astronaut ics , July 1959

Det ra , R. W. ; Riddell, F. R. ; and Rose, P. H. : Controlled Recovery of Non- Lifting Sate l l i tes . Resea rch Repor t 54, AVCO Resea rch Labora tor ies , A Divi- s ion of AVCO Corporat ion, May 1959

Drag Re- en t ry Body Study. ( I l lus t ra ted brochure) . Convair , ZP-268, CN- 79561, Apr i l 1959

Sandgren, F. B. ; Belfiglio, R. A. ; and Romick, D. C. : "Recoverable Boos te rs a r e Studied to Cut Manned Space Flight Cost," Miss i l es and Rockets. Apr i l 1959

ER 10384: Dyna-Soar Escape System Report . Ba l t imore , Md. , The Mart in Company, March 1959, A F No. 59RDZ-25, P ro j ec t WS4646, Contract No. AF33(600)-3770


ADZ-6696: Dyna-Soar Escape Subsystem, P e r f o r m a n c e Specification. MSF No. 20, Ba l t imore , Md. , The Mar t in Company, March 1959, P ro j ec t US464L, Contract No. AF'33(600)-3770

Heise r , G. D. : Resul ts f r o m Wind Tunnel Tes t s of the GE-Mark 2 Nose Cone Data Capsule with Modifications Designed to Improve the Aerodynamic Stability. Genera l E l ec t r i c Company, R59SD334, CN-71135, M a r c h 1959

Detra , R. W. and Riddell, F. R. : Returning Alive f r o m Space. AVCO Research L a b . , CN-71841, 1959

GER- 9003: In te r im Technical Report on Balloon- Type Stabilization and Decel- era t ion fo r High- Altitude and High-Speed Recovery. Goodyear Aerospace Cor - poration, Akron, Ohio, 1 October 1958

GER-8844: P roposa l f o r Study of Inflatable S t ruc ture Mater ia l s f o r Space Ap- plication. Goodyear Aerospace Corporat ion, 26 May 1958

0-1 ,850 ,000 F t , Table of Dynamic P r e s s u r e s a t a Mach Number of One fo r Altitudes f r o m 0- 150,000 F t . Goodyear Aerospace Corporat ion Memorandum DAD 428, Rev. A, Apr i l 1958

Wilcox, B. : The Calculation of Fil l ing Time and Trans ien t Loads for a P a r a - chute Canopy during Deployment and Opening. Report No. SC-4141 (TR), Sandia Corporat ion ( subs id ia ry of Wes te rn E l ec t r i c Company), F e b r u a r y 1958

P roposa l fo r a Recovery Sys tem for NASA Manned Satell i te Capsule. Cook Resea rch L a b . , CN-68108, P-1605A, 1958

Linnell, D. : Ver t ica l Re-en t ry of Very Lightweight Bodies into the E a r t h ' s Atmosphere . Resea rch Note 9, Convair Scientific Resea rch Lab. , A Division of Genera l Dynamics Corporation, October 1957

Schilling, D. L. : A Method for Determining Parachute Opening Shock F o r c e s . Report No. 12543, Lockheed Ai rc ra f t , August 1957

Dole, S. H. : The Atmosphere of Venus. Rand P a p e r P-978, Rand Corpor - at ion, October 1956

GER- 826 5: Supplementary Ae r odynamic Analysis of Cockpit Capsule Concept fo r Multiplace A i r c r a f t Escape Study. Goodyear Aerospace Corporation, Akron, Ohio, July, Contract AF33(616)-5017

Gendtner, W. J. : Sharp and Blunted Cone F o r c e Coefficients and Cente rs of P r e s s u r e f r o m Wind Tunnel Tes t s a t Mach Numbers f r o m 0. 50 to 4. 06. Con- v a i r Repor t ZA-7-017, June 1955

Ciffrin, A. : Aerodynamic Appra i sa l of the Rotofoil. Radioplane Report No. 633, M a r c h 1952


GER-4552: E jec tab le S e a t Capsu le F i n a l R e p o r t , T a s k I. Goodyear A e r o s p a c e Corpora t ion , Akron , Ohio, D e c e m b e r 1951, C o n t r a c t NOa(s) - 51-292- C

R e p o r t R-65: Handbook f o r the Des ign of Guided M i s s i l e R e c o v e r y S y s t e m s ( U ) , T a s k 11, P r o j e c t Recovery . Radioplane Company, Van Nuys, C a l i f . , M a r c h 195 1 (CONFIDENTIAL).

Ran tzs che , W.; and Wendt, H. : Cones in Super son ic Flow. RAND T - 8 , Janu- a r y 1948

APPENDIX A CER-12616

VI - UNIVERSITY TECHNICAL REPORTS

McConnell, D. G. : An Investigation of T rans i en t Melting Ablation a t the Sur - face of a Decelera t ing Spher ica l Body. Case Insti tute of Technology, Cleve- land, Ohio, N65- 16341, 1964

Nichols, J. 0.; and Nierengar ten, E. A. : Aerodynamic Cha rac t e r i s t i c s of Blunt Bodies. JPL-TR-83-677, N- 116-287, November 1964

Law, E. H. : The Longitudinal Equations of Motion of a n Ai rborne Towed Ve- hic le Incorporating a n Approximation of Cable Drag and Iner t ia Effects. P r ince ton Universi ty, Pr inceton, N. J, , Report 687, AD-602734, N65-10904, May 1964

Eichhorn, R.; and Smal l , S. : Exper iments on the Lift and Drag of Spheres Suspended i n a Poiseui l le Flow. Pr ince ton Universi ty, P r ince ton , N. J. , Technical Report PR- 106-P, AD-434449, N64- 19636, F e b r u a r y 1964

Glauz, W. D. : Aerodynamic F o r c e s onosc i l l a t ing Cones and Ogive Bodies in Supersonic Flow. Purdue Univers i ty (Thes i s - Ph. D. ) CN- 11 6- 592, January 1964

Jal le , P. : Hypersonic Bal l is t ic Range Resul ts of Two P lane ta ry Study Configu- ra t ions i n A i r and Carbon Dioxide/Nitrogen Mixtures . J P L Technical Repor t No. 32- 543, Pasadena , Calif. , J e t Propuls ion Lab. , Universi ty of Calif. , January 1964

Kawmura, R. ; Sawada, T. ; and Seki, K. : Study of Row of C i r cu l a r Cylinders i n Supersonic and Hypersonic Flow. 111 - Brag of Row of P a r a l l e l C i r cu l a r Cylinders i n Supersonic Flow, Universi ty of Tokyo, Aeronaut ical Resea rch Insti tute, Bulletin, Vol 3, A64- 14916, December 1963

Harlum, P. : A Table of M a r s Atmosphere and Uncertainty i n the CGS System. Pasadena, Calif. , J e t Propuls ion Lab. , California Inst i tute of Technology, July 1 963

Dayman, B. ; e t a l . : The Influence of Shape on Aerodynamic Damping of Osci l - la tory Motion during M a r s Atmosphere En t ry and Measurement of P i tch Damp- ing a t L a r g e Oscil lat ion Amplitudes. J P L Technical Report No. 32-380, P a s a - dena, Calif. , J e t Propuls ion Labora tory , Univers i ty of Cal i fornia , F e b r u a r y 1963


Maslach, G. J.; and Schaaf , S. A. : Cylinder Drag in the Trans i t ion f r o m Con- tinuum to F r e e Molecule Flow. Universi ty of California, Phys ics of Fluids , Vol 6, A63-14883, M a r c h 1963

Mackworth, J. C. : Aerodynamic Instabil i ty of Non-lifting Bodies Towed Be- neath an Ai rc ra f t . Toronto Univers i ty , Inst i tute of Aerophysics , Canada, UTIA-TN-65, N63- 14844, January 1963

A Genera l Study of P r o c e s s e s fo r the Realization of Design Configurations in Mate r ia l s . I n t e r im Technical P r o g r e s s Repor t No. 2 , Corne l l Aeronaut ical Labora tory , N63- 18026, Apr i l 1962

Vijuk, R. M. : A Study of Automatic Brake Control Sys tems . Report No. 2 , Pennsylvania State Univers i ty , N64-81699, Apr i l 1962

Aroes ty , J. : Sphere Drag in a Low Density Supersonic Flow. Inst i tute of En- gineering Resea rch , Univers i ty of California (submit ted in pa r t i a l sa t is fact ion of the requ i rements fo r the deg ree of Ph. D. in engineering sc ience) , HE- 150- 192, N-107-475, January 1962

Maas , W. L. : Exper imenta l Determinat ion of Pitching Moment and Damping Coefficients of a Cone in Low Density, Hype rsonic Flow. Universi ty of Cali- fornia , Inst i tute of Engineering Resea rch , TR HE- 150- 190, Se r i e s 20, I s sue No. 135, AD-266787, 9 October 1961

Haak, E . L. : Stability and Drag Parachutes with Varying Effective Porosi ty . Lec ture , Universi ty of Minnesota, Summer Course , 17-28 July 1961

Wegener, P. P. and Ashkenas , H. : Wind Tunnel Measurements of Sphere Drag a t Supersonic Speeds and Low Reynolds Numbers . J P L - TR-34- 160, N63 - 18848, June 1961

Ruger , C . J. : Approximate Solutions for Aerodynamics Heating of Re- entry Vehicles. Polytechnic Inst i tute of Brooklyn, PIBAL Report No. 729, AD- 268826, November 1961

Heinrich, H. G. : "Snatch Force , " Chapter V of Aerodynamic Deceleration. Minneapolis, Minn. , Univers i ty of Minnesota Cente r fo r Continuation Study in Cooperation with the Depar tment of Aeronaut ics and Engineering Mechanics, July 1 96 1

Heinrich, H. G.; and Monson, D. J. : "St ress Analysis of Parachutes ." Chapter VI of Aerodynamic Decelera t ion, Minneapolis, Minn. , Universi ty of Minnesota Cente r of Continuation Study in Cooperation with the Depar tment of Aeronautics and Engineering Mechanics , July 196 1

Heinr ich, H. G. ; et a l . : Theore t ica l Pa rachu t e Investigations. P r o g r e s s Re- po r t s , Contract AF33(616)-6372, Univers i ty of Minnesota, January 1960 through January 1 96 1

Sreekanth, A. K. : Drag Measurements on C i r cu l a r Cylinders and Spheres in the Transi t ion Regime a t a Mach Number of 2 , Inst i tute of Aerophysics , Uni- ve r s i t y of Toronto, Aeronaut ical Resea rch Labora tory , UTIA Report 74, ARL- 53, N-98428, Apr i l 1961

Wegener, P. P. : A New Method to Measu re Sphere Drag in Raref ied Super- sonic Gas Flows and Some Resul ts . JPL-TR-34-44, N-81857

Heinr ich and Riobokin: Analytical and Exper imental Considerations of the Ve- locity Distr ibution in the Wake of a Body of Revolution. Depar tment of Aero- nautical Engineering, Universi ty of Minnesota, December 1959

Maslach, G. J. ; and Talbot, L . : Low-Density Aerodynamic Cha rac t e r i s t i c s of a Cone a t Angle of Attack. Univers i ty of California, Technical Report HE- 150-172, October 1959

MIT-DSR No. 5-7426: Text i le Division, Mechanical Engineering Depar tment , MIT, August 1957, AD- 139272, Mate r ia l s and Parachutes and Retardat ion De- v ices . Notes on Special Summer P r o g r a m , MIT, 20-3 1 July 1959

Miele, A.; and Cappel lar i , J. 0. : Effect of Drag Modulation on the Maximum Decelera t ion Encountered by a Re- entering Bal l is t ic Miss i le . Purdue Univer- s i ty School of Aeronaut ical Engineering, N- 73265, June 1959

Hammit t , A. G.; and Murphy, K. R. A. : Approximate Solutions fo r Supersonic Flow Over Wedges and Cones. Pr inceton Universi ty, F o r r e s t a l Resea rch Cen- t e r Report No. 449, Apr i l 1959

Bobrovnikoff, N. T. : Natural Environment of the Planet Mars . Ohio Sta te Universi ty Resea rch Foundation, TN 847- 1 , AD-2421 77, F e b r u a r y 1959

Shaw, J. H.; and Bobrovnikoff, N. T. : Natural Environment of the Planet Venus. Ohio State Universi ty Resea rch Foundation, TN 847-2, AD-242 176, Feb rua ry 1959

Kendall, J. M. , J r . : Exper iments on Supersonic Blunt-Body Flows. J P L - CIT P r o g r e s s Report No. 20-372, F e b r u a r y 1959

Mater ia l s fo r Parachute and Retardat ion Devices. MIT, Lec ture Notes, Sum- m e r Sess ions , 1959

Heinrich, H. G. : Dynamic P rob l ems of Retardation Devices. Lec ture Notes, Parachute Course , Universi ty of Minnesota, 1959

Munson, A. G. : A P r e l i m i n a r y Exper imenta l Investigation of the Flow Over Simple Bodies of Revolution a t M = 18. 4 in Helium. GALCIT Memorandum No. 35 (Contract No. DA-04-495-Ord- 19), December 1956


Machell , R. M.; and OIBryant , W. T. : An Exper imenta l Investigation of the Flow Over Blunt-Nosed Cones a t a Mach Number of 5.8. GALCIT Memoran- dum No. 32 (Contract No. DA-04-495-Ord- 19), June 1956

Moore, R. G. : "Radar Reflectivity of Metall ized Parachutes!' P a p e r p resen ted a t Parachute Engineering Short Course a t Purdue Universi ty, June 1956

Ashley, H. : Dynamic Stability of a Body Moving through the Ai r . MIT Pa ra - chute Technology Notes, June 1955

Ol iver , R. E. : An Exper imental Investigation of Flow Over Simple Blunt Bodies a t a Nominal Mach Number of 5 .8 . Guggenheim Aeronaut ical Laboratory, Cali- fornia Inst i tute of Technology, Wind Tunnel Memorandum No. 26, June 1955

Wedderspoon, J. R. ; and Young, A. D. : Note on the Resul ts of Some Prof i l e Drag Calculations for a Pa r t i cu l a r Body of Revolution a t Supersonic Speeds. College of Aeronaut ics , Cranfield, England, Report 8 1, N-3452 1 , July 1954.

Marson , G . B. ; Keates , R. E.; and Socha, W. : An Exper imental Investigation of the P r e s s u r e Distr ibution on Five Bodies of Revolution a t Mach Numbers of 2. 45 and 3. 19. College of Aeronaut ics , Cranf ie ld , England, Report 79, Apr i l 1954

Ipsen, D. C. : Cone Drag in a Raref ied Gas Flow. Universi ty of California Engineering P ro j ec t s , Report HE- 150- 114, August 1953

Foote, J. R.; and Scherberg , M. G. : Dynamics of the Opening Parachute . Ohio State Universi ty Engineering Exper imenta l Station Bulletin, September 1952, 149: 131-143

Sherman, F. S; and Kane, E. D. : Supplementary Data on Sphere Drag T e s t s . Universi ty of California Engineering P ro j ec t s Report HE-1 50- 71, Feb rua ry 1950

Kane, E. D. : Drag F o r c e s on Spheres in Low Density Supersonic Gas Flow. Universi ty of California Engineering P ro j ec t s , Report HE-150-65, Feb rua ry 1950

Hodges, A. J. : The Drag Coefficient of Very High Velocity Spheres . New Mexico School of Mines, Resea rch and Development Division, October 1949

Staff of the Computing Section, Cente r of Analysis (under di rect ion of Zdenek Kopal): Tables of Supersonic Flow around Cones of La rge Yaw, Technical Re- po r t No. 5, MIT, 1949

Staff of Computing Section, Cente r of Analysis (under di rect ion of Zdenek Kopal): Tables of Supersonic Flow around Cones , Technical Report No. 1 , MIT, 1947


Staff of the Computing Section, Center of Analysis (under di rect ion of Zdenek Kopal): Tables of Supersonic Flow around Yawing Cones , Technical Repor t No. 3, MIT, 1947

Kniper, G. P. : The Atmospheres of t he E a r t h and Planets . Univers i ty of Chicago P r e s s , 1947

Stewart , H. J. : Theore t ica l Lift and Drag of Cones a t Supersonic Speeds. J P L Memorandum 4- 14, N63 -83866, November 1946

Reagan, J. F.; and S t imler , F. J. : The Development of a n Analytical Method fo r Investigating Parachute Stability. Guggenheim Ai r sh ip Insti tute Repor t DGAI 134, October 1945

Harleman, D. : A F Technical Report 5985, P a r t 4, Studies on the Validity of the Hydraulic Analogy to Supersonic Flow, Massachuse t t s Institute of Tech- nology, Cambridge, Mass .

Von Karman, T . : The P rob l em of Res i s tance in Compress ib le Fluids . GALCIT Pub. No. 75, 1936.


VII - SYMPOSIUMS AND PAPERS

Lyons, W . C. : "Hypersonic Drag Stability and Wake Data fo r Cones and Spheres!' ALAA Journa l , November 1964, pp 1948-1956

Barzda , J. J. : "Rotors fo r Recovery!' In Amer i can Insti tute of Aeronaut ics and Astronaut ics , En t ry Technology Conference, (Technical P a p e r s , AIAA Publication CP-9 , New York, Amer i can Insti tute of Aeronaut ics and As t ro- naut ics) , A64-26656, October 19 64

Rober t s , L. : "Entry Into P l ane t a ry Atmospheres!' Astronaut ics and Aer0na.u- t i c s , October 1964

Topping, A. D. : "Shear Deflections and Buckling Cha rac t e r i s t i c s of Inflated Members." Journal of A i r c r a f t , Vol 1 , September-October 1964

Kendall, R. T. : "The Paracone - A Replacement fo r the Parachute!' In Joint Parachute T e s t Faci l i ty Proceed ings , Symposium on Parachute Technology and Evaluation, Vol I , X65- 10845, September 1964

Nebiker, F. R. : "Expandable Drag Devices for Mach 10 Flight Regime!' In Joint Parachute Tes t Faci l i ty Proceedings , Symposium on Parachute Tech- nology and Evaluation, Vol I , X65- 10841, September 1964

Cobb, D. B. : "Parachute Tes t Work a t the Royal A i r c r a f t Establishment!' In Joint Parachute Tes t Faci l i ty Proceedings . Symposium on Parachute Tech- nology and Evaluation, Vol I, X65- 10852, September 1964

Ross , J. H. : "Unique Flexible Fibrous Mater ia l s fo r Decelerators." In Joint Parachute T e s t Faci l i ty Proceedings . Symposium on Parachute Technology and Evaluation, Vol 11, X65- 10827, September 1964

Babish, C. A.; and Nickel, W. E. : "The C r e e Vehicle - A F r e e Flight Aerody- namic Dece le ra to r Test ing System." In Joint Parachute T e s t Faci l i ty Proceed- ings , Symposium on Parachute Technology and Evaluation, Vol I, X65- 10859, September 196 4

Gray , J. I-I. : "Attenuation of Deployment and Opening F o r c e s of Cer ta in Aero- dynamic Dece le ra to rs .I1 In Joint Parachute Tes t Faci l i ty Proceedings , Sym- posium on Parachute Technology and Evaluation, Vol 11, X65- 10832, Septem- b e r 1964


Blow, C. M. : ssThe Development and Test ing of E l a s tomer i c Mate r ia l s f o r Fluid Sealing Applications ." Br i t i sh Hydromechanics R e s e a r c h As sociat ion, International Conference on Fluid Sealing, Second, Cranfield, England, Apr i l 1964, A i r c r a f t Engineering, Vol 36, A64-24812, July 1964.

G r o s s , R. S.: and Re i s s , G. W. : he A s s e t Recovery system:' In Ae rospace Corporat ion, T rans . of the Ninth Symposium on Bal l is t ic Miss i l e and Space Technology, Vol 11, X65- 1361 0, July 1964

Fink, Ad. R. : "Hypersonic Dynamic Stabil i ty of Sha rp and Blunt Slender Cones." In Aerospace Corporat ion, T rans . of the Ninth Symposium on Bal l is t ic Miss i le and Space Technology, Vol 11, X65- 13609, July 1964

Houtz, N. E. : "Optimization of Inflatable Drag Devices by Isotensoid Design." AIAA P a p e r 64-437, A64-20102, July 1964

Fox, N. L.; and Blaylock, R. F. : "Aerodynamic Effects of Atmospher ic , Com- position." AIAA P a p e r 64-48 1 , Arner ican Insti tute of Aeronaut ics and As t ro - nautic s , June 1 964

Krah, J. W. : "High Tempera tu r e Te l eme t ry Antennas f o r Asset." In Ohio State Universi ty and USAF R e s e a r c h and Technology Division, Symposium on Elec- t ro-Magnet ic Windows Proceedings , Vol 4, A65- 11382, 2-4 June 1964

Dastin, S. J'.; and Rosenberg, P. : "Reinforced P l a s t i c s f o r P ro j ec t F i r e Re- en t ry Vehicle? P r e p a r e d fo r p resen ta t ion a t Society of P l a s t i c s Engineers Regional Technology Conference, X64- 12048, May 1964

Cobb, D. B. : "Parachute T e s t Work a t the Royal A i r c r a f t Establ ishment ." Symposium (on Parachute Technology, E l Centro , Calif. , Apr i l 1964

Brady , J. J,,; and Levenste ins , Z . J. : "Hypersonic Drag, Stability, and Wake Data fo r Cones and Spheres ." A I M P a p e r 64-44, A64- 1293 1, January 1964

Jackson, B. G. : "Aerodynamic Drag and Stability." In Manned Spacecraf t - Engineering Design and Operation. Edited by P. E. P u r s e r , M. A. Fage t , and N. F. Smith, Fa i rch i ld Publications, Inc. , A65- 12535, 1964

Finch, T. W . : ' lAerodynamic Braking T ra j ec to r i e s fo r P l ane t a ry Orbi t Attain- ment!' AIAA. P a p e r 64-478, N64-24165, 1964

Nerem, R. ILZ.; and Stickford, G. H. : "Shock Layer Radiation during Hyper- velocity Re- entry.'' In Amer i can Insti tute of Aeronaut ics and As t ronau t ics , En t ry Technology Conference ( A U A Publication CP- 9, New York, Amer i can Insti tute of Aeronaut ics and As t ronau t ics , 1964), A64-26664

Wasse rman , L.; and Sla t tery , J. C. : "Upper and Lower Bounds on the Drag Co- efficient of a. Sphere i n a Power- Model Fluid." Amer i can iilstitute of Che-mical Engineers , Annual Meeting, 56th Symposium on Non- Newtonian Fluid Mechan- i c s - I, P a p e r 40B, A63-25855, December 1963,


F rench , K. E. : "Inflation of a Parachute." AIAA Journal , November 1963

Barzda , J. J. : "Resul ts of the Kaman KRC- 6M Rotochute T e s t s a t Supersonic Speeds." Amer i can Helicopter Society Journal , Vol 8 , A64- 10791, October 1963

G r o s s , F. R. : "Orbital Recovery with Expandable P r e s s u r i z e d Drag Bodies. "

Society of Automotive Engineers , National Aeronaut ic and Space Engineering and Manufacturing Meeting, P a p e r 756A, A63- 24096, September 1963

Pe t e r s en , N. V. (ed. ): "Advanced i n the Astronaut ical Sciences." Vol 16, P a r t 1 , Space Rendezvous, Rescue , and Recovery. USAF and Amer i can Astronaut i - ca l Society, Space Rendezvous, Rescue and Recovery Symposium, A63-24744, September 1963

Moss , B. : "Lifting and Non-lifting Dece le ra to rs fo r Boosters and Satell i te Re- covery." In Space Rendezvous, Rescue , and Recovery Proceedings of the Amer i can Astronaut ical Society, Symposium, A i r F o r c e Flight Tes t Cente r , Edwards AFB, Advances i n the Astronaut ical Sciences , Vol 16, P a r t 2, A64- 27828, September 1963

Gonor, A. L. : "On Three-Dimensional Bodies of Minimum Drag a t High Super- sonic Speed!' Journa l of Applied Mathemat ics and Mechanics, Vo1 27, No. 1 , Tra-nslation, A63- 19259, July 1963

Simon, W. E.; and Walter , L. A . : "Approximation for Supersonic Flow Over Cones." AIAA Journal , Vol I (Mart in Mar ie t t a Corporat ion) , July 1963

Heinrich, H. G. : "A Supersonic Parachute Based on the Inlet Diffuser Concept. "

P re sen t ed a t the 22nd Meeting of the Flight Mechanics Panel , Tor ino, Italy, N64- 16209, AGARD- 445, Apr i l 1963

Chow, W. L. : "Conical F la r ings in Uniform Supersonic Flow a t Z e r o Angle of ~ t t a c k . " ALAA Journal , Vol 1 , A63 - 15969, Apr i l 1963

Nebiker, F. R. : "Expandable Balloon-Type Drag Devices f o r Mach 10 Flight ~ e ~ i m e ! ' Society of Automotive Engineers - Amer i can Society of Naval Engi- n e e r s , National Aeronaut ical Meeting, A63- 14457, Apr i l 1963

Bulakh, B. M. : "On the Nonsymmetr ic Hypersonic Flow a r a n d a C i r cu l a r Cone." Journa l of Applied Mathemat ics and Mechanics, Vol 26, Transla t ion, March 1963

Schaaf, S. A.; and Maslach, G. J. : "Cylinder Drag in the Trans i t ion f r o m Con- t inuum to F r e e Molecule Flow." Physics of Fluids , Vol 6 , A63-14883, March 1963

Mart in , W. A. : "Mach 3 Technology and the Recoverable ~ o o s t e r . " Inst i tute of the Aerospace Sciences Annual Meeting 31st , IAS P a p e r 63-7, A63-11437, - January 1963

A- 51


S ims , L. We : Evolution of the Hyperflo Parachute . In A F Sys tems Command Trans . of the 8 th Symposium on Bal l is t ic Miss i l e and Space Technology, Vol 2, N64- 15261, 1963

Brendel , J. : The Mark VB Recovery Sys tem (U). A i r F o r c e Sys tems Com- mand, Los Anglees, Calif. , Space Sys tems Division, T rans . of the 8th Sym- posium on Bal l is t ic Miss i l e and Space Technology, Vo1 7 , 1963 (See X64- 13261) (SECRET).

Spalding, D. B. : "A New Analytical Exp re s s ion fo r the Drag of a F la t P l a t e Valid for Bo,th the Turbulent and Lamina r Regimes." International Journa l of Heat and Mass T r a n s f e r , Vol 5, December 1962, A63- 11 124

Gunkel, R. J. ; Bond, P. ; and Bergonz, F. H. : "Recovery Sys tem Concepts fo r a Reusable Chemical Booster." Amer i can Rocket Society, Annual Meeting, 17th and Space Flight Exposition, P a p e r 2718-62, A63- 12764, November 1962

Solt, G. A . , Jr. : "Aerodynamic Dece le ra to r - Thei r Use and Future." P r o - ceedings of Retardat ion and Recovery Symposium (ASD), N63-23327, Novem- be r 1962

Oberg, A. J. ; Sopczak, S. S. ; and Sutton, M. A. : "Paravulcoon Recovery and Landing System." In Aeronaut ics Sys tems Division Proceedings of Retardat ion and Recover-y Symposium, N63-23324, November 1962

Buckner, J. K. : "Application of Axisymmetr ic Flow Analysis t o Inflation Sta- bility of Supersonic Flexible Parachute." In Aeronaut ics Sys tems Division P r o - ceedings of Etetardation and Recovery Symposium, N63-233 18, November 1962

Knacke, T. W. : "Systems Considerations!' In Aeronaut ics Sys tems Division Proceedings of Retardat ion and Recovery Symposium, N63-23325, November 1962

Rose , P. H. : "Heating P r o b l e m for Supersate l l i te Re- entry." In Aeronaut ics Sys tems Division Proceedings of Retardat ion and Recovery Symposium,N63- 233 15, November 1962

Ross , J. H. : "High Tempera tu r e F ibrous Mater ia l s f o r Decelcrators." In Aeronaut ics Sys tems Division Proceedings of Retardat ion and Recovery Syrn- posium, N63-23320, November 1962

Babish, C. k.; and Berndt , R . J. : "Supersonic Parachute Rcscarch." In Aero- naut ics Sys tems Division Proceedings of Retardat ion and Recovery Symposium N63-23317, IVovember 1962

McMullen, J. C.; and Smith, A. M. : "Mar t ian En t ry Capsule - Design Consid- era t ions f o r Te rmina l Deceleration." USAF, Office of Scientif ic R e s e a r c h and Gene ra l E l ec t r i c Co. , Space Sc iences Labora tory , Dynamics of Manned Lift- ing P l ane t a ry Ent ry , Symposium 3 rd , Proceedings , A63-23666, October 1962


Hoshizaki, H. : "Heat T r a n s f e r i n P lane ta ry Atmospheres a t Super-sate l l i te Speeds." Amer i can Rocket Society Journal , October 1962

Bogdonoff, S. M.; and Vas, I. E . : "Some Exper iments on Hypersonic Separated Flows!' Amer i can Rocket Society Journal , October 1962

Ginter , R. L.; and C e r r e t a , L. M. : "Insulation- Radiation Tempera tu r e Control of Inflatable Hypersonic Vehicles!' P a p e r 5956, SAE, October 1962

Cobb, E. S. : High Strength G la s s F ibe r Tapes and Webbings fo r High Tem- pe ra tu r e P r e s s u r e Packed Decelera tor Applications. Collection of P a p e r s p resen ted a t Symposium on F ibrous Mat te r , X63- 12491, October 1962

H a r r i s , J. T. : "High Tempera tu r e Metall ic F a b r i c fo r Re-en t ry Applications, Society of Automotive Engineers!' National Aerospace Engineering and Manu- facturing Meeting, P a p e r 5904, A63- 12409, October 1962

St. Germain , A. R.; and Zick, L. P. : "Circumferent ia l S t r e s s e s in P r e s s u r e Vesse l Shells of Revolution." Repor t f r o m T r a n s . of the ASME, Journa l of Eng. for Ind. p resen ted a t the Pe t ro . Mech. Eng. Conference, N64-20675, Septem- be r , 1962, ASME P a p e r 62 -PET-4

Stocker , P. M.; and Mauger, F. F. : "Supersonic Flow P a s t Cones of Genera l Cross-Section." Journa l Fluid Mech. , Vol 13, P a r t 3 (Armament Resea rch and Development Establ ishment , W a r Office), July 1962

Edsal l , R. H. : "Calculation of Flow Fields about Blunt Bodies of Revolution Travel ing a t E S cape Velocity." New York Amer i can Rocket Society, presented a t the ARS Lunar Missions Meeting, ARS Pape r 2492- 62, N62- 14463, July 1962

Brooks, W. B.; and Reis , F. E . : "Drag on a Right C i r cu l a r Cylinder in Ra re - fied Flow a t Low Speed-Ratios!' In Office of Naval Resea rch Proceedings of the 3 r d Intern. Symposium on Raref ied Gas Dynamics, N63 -2 1603, June 1962.

Aroes ty , J. : "Sphere Drag in a Low-Density Supersonic Flow." In Office of Naval Res. Proceedings of the 3 r d Intern . Symposium on Raref ied Gas Dynamics, ~ 6 3 - 2 1 6 0 1 , June 1962

Ashkenas, H. : "Low-Density Sphere Drag with Equi l ibr ium and Nonequil ibrium Wall Temperature!' Intern. Symposium on Raref ied Gas Dynamics, Proceedings of 3 rd Intern . Symposium held in P a r i s , June 1962

Aroesty , J. : "Sphere Drag in a Low Density Supersonic Flow." In Office of Naval Res . Proceedings of the 3 r d Intern . Symposium on Raref ied Gas Dynamics, ~ 6 3 - 2 1 6 0 1 , June 1962

Ashkenas , H. : "Low- Density Sphere Drag with Equi l ibr ium and Nonequilibrium Wall Temperature!' J P L Insti tute of Technology. In Office of Naval Res . P r o - ceedings of the 3 r d Intern . Symposium on Raref ied Gas Dynamics, June 1962, N63- 21602


Bloxsom, D. E.; and Rhodes, B. V. : "Exper imental Effect of Bluntness and Gas Rarefac t ion on Drag Coefficients and Stagnation Hea t T rans f e r on Axisym- m e t r i c Shapes in Hypersonic Flow." Inst i tute of the Aerospace Sciences , National S u m m e r Meeting, A63 - 1 12 18, June 1962

Traugott , S. C. : "Some Fea tu re s of Supersonic and Hypersonic Flow About Blunted Cones." Journa l of Aero. Science, Vol 29, Apr i l 1962

Wood, C. J. : "Hypersonic Flow over Spiked Cones." Journa l Fluid Mech. , Vol 12, P a r t 4, Apr i l 1962

P r i t cha rd , 13. B. : "Aerodynamic Control of Decelera t ion and Range for the Lunar Mission." P rep r in t P a p e r 513D for Presen ta t ion a t the SAE National Aeronaut ics Meeting, N62- 12501, Apr i l 1962

Meyer , J. B.; and Mayo, B. R. : "Emergency and Routine Space Vehicle Re- covery." Inst i tute of Radio Engineers , Intern. Convention, IRE Intern. Con- vention Record , A63- 12527, March 1962

Burke, A. F'.; and Cur t i s , J. H. : "Blunt-Cone P r e s s u r e Distr ibutions a t Hyper- sonic Mach IYumbers!' Journa l Aerospace Science, Vo1 29, F e b r u a r y 1962

Lees , L.; and Hromas , L. : "Turbulent Diffusion in the Wake of a Blunt-Nosed Body a t Hypersonic Speeds." IAS P a p e r No. 62-71, January 1962

Lor sch , H. G. : "Heat T r a n s f e r to Porous Nose Caps and Leading Edges of Hypersonic 'Vehicles and Re- en t ry Aids." In Advances i n the As t ronau t ica l Sciences , Vol XI, edited by H. Jacobs , Amer i can Astronaut ical Society, An- nual Meeting, 8 th Proceeding, A64- 11472, January 1962

Walts , F. M. : " ~ e - e n t r y / ~ e c o v e r y Design Considerations of a Lunar Re turn Data Vehicle." P re sen t ed a t the AAS 8 th Annual National Meeting, AAS 62-40, N- 108-097, January 1962

Edsal , R. H. : "Calculation of Flow Fields about Blunt Bodies of Revolution Traveling a t Escape Velocity." New York Amer i can Rocket Society, N62- 14463, 1962

Sla t tery , R. E.; and Clay, W. G. : "Width of the Turbulent T r a i l behind a Hy- perveloci ty Sphere." Physics of Fluids , Vol 4, No. 10, October 1961

Hamilton, J. S. : "Large Boos te r Recovery Techniques." P re sen t ed a t ARS Space Flight Repor t to the Nation, N- 105-706, October 1961

Hastings, S. M.; and Pas iuk , L. : "The Aerodynamic Heating of Blunt, Axisym- m e t r i c , Re-en t ry Type Bodies with Lamina r Boundary Laye r a t Z e r o and a t L a r g e Angles of Yaw in Supersonic and Hypersonic A i r Streams." In te rn Heat T r a n s f e r Conference, A63-25589, August 1961


A63- 11342: "A Simple Method of Sphere Drag Measurement i n Raref ied Super- sonic Gas Flows." P e t e r P. Wegener and H a r r y Askhenas , California Inst i tute of Technology, J e t Propuls ion Labora tory , Pasadena , Calif. , International Symposium on Raref ied Gas Dynamics, 2nd, Proceedings , Berkeley, Calif. , 3-6 August 1960, In Raref ied Gas Dynamics , New York, Academic P r e s s , Inc . , 1961

Dukes, W. H. : "Requirements f o r High Tempera tu r e Mater ia l s f o r Hypersonic Re- en t ry Vehicles. I' In High Tempera tu r e Mater ia l s . P a r t 2, Metal lurgical Society Conferences , A63 -252 16, Apr i l 196 1

Lysdale , C. A. : "Launch-Vehicle Recovery Techniques,'' p resen ted a t IAS 29th Annual Meeting, U S Pape r No. 61- 51, N- 92279, January 1961

Lysdale , C. A. : "Boos te r Recovery Concepts," p resen ted a t ASS 7th Annual Meeting, ASS P rep r in t 61 - 2 1, N95446, January 196 1

Luidens, R. W. : I1Atmospheric Braking f o r Space Missions." F o r presenta t ion a t 1961 A F B M D / A ~ ~ O S ~ ~ C ~ Corporat ion Symposium, NASA CC-E- 1270, 1961

Maynard, J. D. : "Aerodynamics of Dece le ra to rs a t Supersonic Speeds!' Sym- posium of Recovery of Space Vehicles sponsored by the Los Angeles Section of the Inst i tute of the Aero. Sc i . , September 1960

Maynard, J. D. : "Aerodynamics of Dece le ra to rs a t Supersonic Spceds." NASA/ Langley Resea rch Cente r (for presenta t ion a t the Symposium on Recovery of Space Vehicles i n Los Angeles, Calif. f r o m August 3 1 to September 1 1960)

Skhlovskii, I. S.; and Kurt , V. G. : "Dcterminst ion of Atmospher ic Density a s a Height of 430 km by Means of the Diffusion of Sodium Vapors." ARS Journal , Vol 30, No. 7 , July 1960

Strong, J. R.; and Moores , C. B. : "Some Observat ions of the Atmospheres of Venus and the E a r t h during the Stra tola IV Balloon Flight." Pape r given a t the Arne r ican Geophysical Union Meeting, Washington, D. C. , Apri l 1960

Connors, J. F.; and Lovell , J. C. : "Some Observat ions on Supersonic Stabili- zation and Decelera t ion Devices." P re sen t ed a t the IAS 28th Annual Meeting, CN-80512, January 1960

Koh, J. C. Y. : "Measured P r e s s u r e Distr ibution and Local Heat T r a n s i e r Rates fo r Flow Over Concave Hemispheres ," p resen ted a t ARS Semi-Annual Meeting. ARS-1146-60, N-85481, 1960

Connors, J. F.; and Lovell , J. C. : "Source Observations on Supersonic Stabi- l ization and Decelera t ion Devices." IAS P a p e r No. 60- 19, 1960

Shipps, R. P. : "On the Methods and Economics of Recovering Boos te rs for Orb i ta l Vehicles." IAS P a p e r No. 60-29, 1960


King- Hele, D. G. : "Density of the Upper Atmosphere f r o m Analysis of Satel- l i te Orbi ts ." F u r t h e r Resu l t s , Nature , Vol 184, October 24 1959 .

Phi l l ips , R. L.; and Cohen, C. B. : "Use of Drag Modulation to Reduce Decel- e ra t ion Loads during Atmospher ic Entry," ARD Journal , June 1959

Parv in , R. H. : "The E a r t h and Ine r t i a l Space. P a r t II- Shape of the Earth." Aerospace Engineering, Vol 18, No. 5, May 1959

P r i t cha rd , E. B. : "The Stability of Seve ra l Miss i l e Nose Configurations i n Hypersonic Flow." Inst i tute of the Aero. Sci. , 1959 1 s t Award P a p e r s , IAS Student Branch P a p e r Competition

VanDyke, W [ . D. : "The Supersonic Blunt Body P r o b l e m - Review and Extension." VAS, Vol 25, No. 8 , August 1958

Thale, J. : "Recovery f r o m a Satel l i te Orbit:' p resen ted a t ARS Semi-Annual Meeting. ARS 650-58, N-61896, June 1958

Romick, D. C. ; Belfiglio, R. A. ; and Sandgren, F. B. : " ~ e c o v e r a b l e Boos t e r s a r e Studied to Cut Manned Space Flight Cost." Miss i l es and Rockets , Apr i l 1958

Herman, R. : "Prob lems of Hypersonic Flight a t the Re-en t ry of Satel l i te Ve- hicles." Proceedings of the 9th Annual Congress of the IAF, Ams te rdam, 1958

Charwat, A. F. : "The Stabil i ty of Bodies of Revolution a t Very High Mach Num- bers." J e t Propuls ion, V 27, No. 8 , P a r t 1, N-68775, August 1957

Ehricke, K. A.; and Pence, H. : " ~ e - e n t r y of Spher ica l Bodies into the Atmos- phere a t Veiry High Speeds." P re sen t ed a t ARS Spring Meeting, ARS 428-57, N-60902, Apr i l 1957

Hodges, A. J. : "The Drag Coefficient of Very High Velocity spheres ." Journal of the Aero. Sci. , Vol 24, 1957

Ipsen, D. C . : "Exper iments on Cone Drag in a Raref ied Ai r Flow." Je t P r o - pulsion, December 1956

Be t r am, M. H. : "Tip-Bluntness Effects on Cone P r e s s u r e a t M = 6.85." Jour - na l Aero. Sc i . , Vol 2 3 , September 1956

Heinrich, H. G. : "Drag and Stability of Parachutes ." Aeronaut ical Engineering Review, June 1956.

Krahn, E. : "Negative Magnus Force." Journa l of the Aeronaut ics Sciences , Vol 2 3 , No. 4, Apr i l 1956

Heinrich, H,. G. : "Drag and Stabil i ty of Parachutes!' U S Engineering Review, Vol 15, Jan-June 1956


Robe r t s , R. C.; and Riley, J. D. : "A Guide to the Use of the MIT Cone Tables .I1

Journa l of Aeronautic a1 Sciences,Vol 2 1 , 1954

Foote, J. R.; and Scherberg , M. G. : "Dynamics of the Opening Parachute." Proceedings of the Second Midwestern Conference on Fluid Dynamics, Ohio State Universi ty, 1952

Van Dyke, M. D. : " F i r s t - O r d e r and Second-Order Theory of Supersonic Flow P a s t Bodies of Revolution." Journa l of Aeronaut ical Sciences, Vol 18, March 1951

Van Dyke, M. D. ; Young, G. W. ; and Sisha, C. : " P r o p e r Use of the MIT Ta- bles for Supersonic Flow P a s t Inclined Cones." Journa l of Aeronaut ical Sci- ences , Vol 18, 1951

O 'Hara , F. : "Notes on the Opening Behavior and the Opening F o r c e s of P a r a - chutes." The Journal of the Royal Aeronaut ical Society, November 1949

C h a r t e r s , A. C.; and Thomas, R. N. : "The Aerodynamic Pe r fo rmance of Smal l Spheres f r o m Subsonic to High Supersonic Velocit ies ." Journa l of Aeronaut ical Sciences , Vol 12, 1945

Hall, A. A.; and Hislop, G. S. : "Velocity and Tempera tu r e Distributions in the Turbulent Wake behind a Heated Body of Revolution." Proceedings of the Cam- bridge Philosophical Society, Vo1 3 4, 1939

Goldstein, S. : "On the Velocity and Tempera tu r e Distr ibution in the Turbulent Wake behind a Heated Body of Revolution." Proceedings of the Cambridge Philosophical Society, Vol 3 4, 1938

Goldstein, S. : "On the Velocity and Tempera tu r e Distr ibution in the Turbulent Wake behind a Heated Body of Revolution." Proceedings of the Cambridge Philosophical Society, Vol 34, 1938

Swain, L. M. : "Turbulent Wake behind a Body of Revolution." Proceedings of the Royal Society of London, Se r i e s A, Vol 125, 1929


VIII - MISCELLANEOUS

Heinrich, H. G. : "Aerodynamic Pr inc ip les of the Supersonic Guide Surface Parachute!' Ber l in , West Germany , P a p e r A64-27037, Sep tember 1964

Niehaus, G. : I' On the Applicability of the Hydraulic Analogy to Investigations of Aerodynamic Decelera t ion Systems." Ber l in , West Germany, P a p e r A64- 26277, Sep tember 1964 ( i n G e r m a n )

Buogiorno, C.; and T re l l a , M. : "Considerations on the Drag Coefficient f o r the San Marco Satellite." Roma, Univers i ta , Scuola Dingegneria, Aerospaz ia le , Centro Ricerche Aerospazia l i , No. 5, July 1964, A65- 15359

B e r r y , C. J . ; David, B. M . ; and Rogers , E . W. E. : Exper iments with Cones in Low-Density Flows a t Mach Numbers Near 2 . National Phys ica l Labora- tory , Teddington, G r e a t Br i ta in , NPL-Aero-1095, X65-12352, March 1964

Krasnov, N. F. : An Approximation of Aerodynamic Coefficients of Thin Bod- i e s of Revolution Moving a t Very G r e a t Supersonic Speeds. T rans l . into Eng- l i sh f r o m T r . , Vyssheye Tekhn. Us chil ishche Iment , Baumana, Moscow, No. 32, FTD-MT-63- 169, AD-605587, N65- 14399, March 1964

Krasnov, N. F. : "Aerodynamics of Bodies of Revolution!' Second Edition, In Russian, Book on Aerodynamics of Bodies of Revolution, A65- 11 430, 1964

Marsden, A. J. : "The Drag and Opening Cha rac t e r i s t i c s of Parachutes of Sev- e r a l Designs when Towed Behind an A i r c r a f t - The i r Consistency and Compari - son with Previous Data!' London, Min. of Aviation, N65-21863, RAE- TN- Mech-Eng-3 90, October 1963

Brown, I. S. H. : "Proper t i es of Rotating Parachutes ." London, Min. of Avi- ation, RAE-TN-Mech-377, X64-10126, May 1963

Kell, C. : F r e e - Flight Measurements of P r e s s u r e Distr ibution a t Transonic and Supers oinic Speeds on Bodies of Revolution having Parabol ic Afte rbodies . Aeronautical1 R e s e a r c h Council, G r e a t Br i t ta in , ARC-RtM-3290, previously i s sued a s RAE-Aero 2605, ARC-20433, N63- 11 902, 1962.

Smith, A. Nl.; and Peck, R. F. : "The Recovery of Flight Tes t P a y l ~ a d s . ~ ~ AGARD Report 397, 1962

Chuskin, P. I.; and Shlishnina, N. P. : Tables of Supersonic Flow about Blunted Cones. Academy of Sciences USSR (moscow), 1961, t rans la ted and edited by J. I?. Springfield, R e s e a r c h and Advanced Development Division AVCO Corporat ion, Wilmington, M a s s . , September 1962


Boyd, E . A . : A e r o d y n a m i c C h a r a c t e r i s t i c s of a Hyperson ic P a r a c h u t e . Col- l ege of A e r o n a u t i c s , G r e a t B r i t t a i n , R e p o r t 162, N- 106- 570, November 196 1 I W a t e r s , M. H. L.; and Browning, A . C. : T h e U s e of P a r a c h u t e s a t High Speed

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and High Alt i tude. Roya l A i r c r a f t E s tab l i shrnent T e c h n i c a l Note Mech. Eng. 340, N-106-710, August 1961

W a t e r s , M. H. L.; and Browning, A . C . : T h e U s e of P a r a c h u t e s a t High Speed and High Alt i tude. T e c h n i c a l Note No. Mech. Eng. 3 40, Royal A i r c r a f t E s t a b l i s h m e n t , AD-267692, Augus t 196 1

T imoshenko , S . P.; a n d G e r e , J. M. : T h e o r y of E l a s t i c Stabi l i ty . Second Edi t ion , New York , McGraw- Hil l Book Company, Inc. , 196 1

R o b e r t s , B. G. : A n E x p e r i m e n t a l Study of the Drag of Rigid Models R e p r e - sent ing Two P a r a c h u t e Des igns a t M = 1. 40 and 2. 0. M i n i s t r y of Avia t ion C. P. No. 565, London, 1961

R o b e r t s , B. G. : An E x p e r i m e n t a l Study of the Drag of Rigid Models R e p r e - sent ing Two P a r a c h u t e Des igns a t M = 1. 40 and 2. 19. Royal A i r c r a f t E s t a b - l i s h m e n t Tech . Note A e r o 2734, N-98050, D e c e m b e r 1960

Z a n d b e r g e r , P. J.; and Von D e r Wal le , F. : The Approx imate Influence of B a s e - D r a g on the O p t i m u m Shape of A x i s y m m e t r i c Configurat ions in L i n e a r - i zed Super son ic Flow. N63-807 19, Nat ional Aeronau t i ca l R e s e a r c h Ins t i tu te , A m s t e r d a m , Ne the r l ands , 1 F e b r u a r y 1960

B a k e r , A.; and Swallow, J. E. : "Impact Tes t ing of Tex t i l e Y a r n s . P a r t I, Ex- p e r i m e n t s wi th a Fa l l ing Weight Method." Tech. Note C h e m . 1355, Royal A i r - c r a f t E s t a b l i s h m e n t , G r e a t B r i t t a i n , AD- 232617, November 1959

Cobb, D. B. : "The Techniques of Measur ing the F o r c e E x e r t e d by a P a r a c h u t e dur ing Opening." T N Mech. Eng. 301, Royal A i r c r a f t E s t a b l i s h m e n t , Oc tober 1959

Urey , H. C . : "The A t m o s p h e r e s of the Planets ." Encyclopedia of P h y s i c s , Vol LII, A s t r o p h y s i c s 111, T h e S o l a r S y s t e m , S p r i n g e r - V e r l a g , B e r l i n , 1959

H o e r n e r , S. F. : Flu id -Dynamic Drag . Pub l i shed by au thor , 1958

K r e i t h , F. : P r i n c i p l e s of Heat T r a n s f e r . In t e rna t iona l Textbook Company, Sc ran ton , Pa. , 1958

Brown, W. D. : P a r a c h u t e s . P i t m a n , No Y . , F i r s t edi t ion, 1957

L iepmann , H. W. and Roshko, A . : E l e m e n t s of G a s Dynamics . John Wiley and Son, New York , 1957


Beastall , D,;; and Turner , J. : The Effect of a Spike Protruding in Front of a Bluff Body a t Supersonj .~ Speeds. Aeronautical Research Council R and .M 300'7, Royal Aircraf t Establishment Tech. Note Aero 2 137 (supersedes RAE Tech. Note Aero 2137), 1957

Schlichting, H. : Boundary Layer Theory. McGraw-Hill, New York, 1955

hlilne- Thompson, L. M. : Theoretical Hydrodynamics. Macmillan, PJ, Y. , Third edition, 1955.

Krause, H. G. L. ; Kaeppeler, H. J. ; Koelle, H. H. and Kubler, M. E. : Determination of Maximum Skin Temperatures Due to Aerodynamic Heating for Unwinged Missiles Re-entering the Atmosphere (Report 6). Astronautisches Forschungsinstifuf Stuttgard, Stuttgart, Germany, July 1954

Ketschin; Kibel; and Rose: Theoretische Hydromechanik. Akademi Verlag, Berlin, 1954

de Vancouleurs, G. : Physics of the Planet Mars . Macmillan, N. Y. , 1954

Shapiro, A. H. : The Dynamics and Thermodynamics of Compressible Fluid Flow. Vols I and 11, The Ronald P r e s s Company, New York, 1954

Pope, A. : Wind Tunnel Testing. Second edition, John Wiley and Sons, New York, 1954

Howarth, L. (ed. ): Modern Developments in Fluid Dynamics, High Speed Flow, Vol 11, Oxford a t the Clarendon P r e s s , 1953

Hoerner, S. F . : Aerodynamic Drag. Midland Park , N. J., published by author, 1951

O'Hara, F. : Notes on the Opening Behavior and Opening Forces of Parachutes. Royal Aeronautical Society Journal, Vol 53, London, November 1949

Leipman, H. W; and Puckett, A. E. : Introduction to Aerodynamics of a Corn.- pressible Fluid. Galcit Aeronautical Ser ies , Wiley, N. Y. , 1947

Lighthill, J. H. : Supersonic Flow P a s t Bodies of Revolution. R and M No. 2003, Bri t ish A. R. C., 1945 ,

F e r r a r i , C. : Determination of the P r e s s u r e Exerted on Solid Bodies of Revo- lution with Pointed Noses Placed Obliquely in a S t ream of Compressible Fluid a t Supersonic Velocity. R. T. P. Translation No. 1105, Bri t ish Ministry of Aircraf t Production (from Atti R. Accad. Sci. Torino, Vol 72, pp 140- 163, 1936

Lamb, H. : Hydrodynamics. Dover, N. Y. , Sixth edition, 1932.

Jones, R. A. : On the Aerodynamic Character is t ics of Parachutes . Bri t ish ARC Report 13 and M No. 862, June 1923