Doc ID: 6636743 Doc Ref ID: A6636742

2/o/vm11/R7lr-68 AVC,AVN/TCOM/. 8 FEBRUARY 1968 2042Z DIST: OSCAR/VICTOR KILO PIDS USM-604, USN-lf14J HCO

MILITARY REGION TRI-THIEN-HUE COMMUNICATIONS,

25 JANUARY 1968

I. INTRODUCTION

This report presents a detailed description of the Military

Region JMR) Tri-Thien-Hue (TTH) manual Morse radio complex as of

25 January. Included in the report is a diagram (in hard copy

only) depicting unit subordination and the most current unit

locations. Arbitrary designators have been assigned to the

unidentified units to facilitate cross-referencing between the

report and the diagram, and will be used in future reports on this

subject.

II. DETAILS

A. Hg_, MR TTH

Hg_, MR TTH maintains direct communications with PAVN High

Command (HC); Hg_, MR 4 (North Vietnam (NVN)); Hg_, MR 5; Hg_, DMZ

Front; probable Hg_, PAVN 559th Transportation Group; and approximately

11 subordinate stations, including the tentative forward element of

Hg_, MR TTH; the possible Hue Municipal Unit and one of its

subordinates (Station Al); the tentative PAVN 4th Regiment; the

possible PAVN 9th Regiment; the PAVN 6th Regiment; and five

unidentified entities (Stations B4, El-E4). During late December-early

January, the Hg_, MR TTH relocated to within 25 km of Hue from the

area of 16-25N 107-23E (YD 554171). This relocation, together with

a 15 km relocation to within 15 km of Hue by the tentative forward

element of Hq, MR TTH, suggests a renewed interest in the Hue city

1 area by Vietnamese Communist elements in MR TTH.

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B. Tentative Forward Element, Hq,.MR TTH

The emergence of the forward element in :tvlR TTH during

late 1967 has been augmented by an increase in the number of

communications subordinates of this headquarters, as well as the

addition of watch and broadcast facilities. The forward element

was possibly activated in July 1967 as a communications subordinate

of both Hq, MR TTH and HC. During September-October 1967, it

ceased communications with Hq, MR TTH and initiated communications

with three terminals that had been subordinates of only Hq, MR TTH-­

the possible Hue Municipal Unit and two unidentified entities

(Stations El and E4). Also during October 1967, the forward

element instituted its own watch facility through which

communications were established with HC; Hq, MR 4 (NVN); and one

unidentified station. During this period, the forward element

used the radio facilities of the possible PAVN 9th Regiment to

communicate with Hq, MR TTH. However, the Hq, PAVN 9th Regiment

first appeared subordinate to the forward element on the watch

facility during November 1967, thus indicating that the forward

element was no longer utilizing the communications facilities of

the Hq, 9th Regiment. The isolation of communications between

the forward element and Hq, MR TTH together with anincreasing

number of stations appearing subordinate to the forward element,

indicated that this headquarters was serving a forward element

function.

In January 1968 the forward element initiated broadcast

communications and relocated from its former operating area

near the possible Hq, PAVN 9th Regiment (16-33N 107-09E, YD 300320)

to an area near 16-24N 107-26E (YD 615143) approximately 15 km

southwest of Hue.

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The current communications subordinates of the forward

element include the possible Hue Municipal Unit and one of its

subordinates (Station Al), the tentative '?AVN 4th Regiment, the

possible PAVN 9th Regiment, the PAVN 6th Regiment, and five

unidentified entities (Stations El-E4, and Fl, which comrntmicates

only with the forward element). All of the forward element's

subordinates--except Fl--comrnunicate directly with Hq, MR 'l'TH.

Two of the unidentified entities (Stations El and E4) have

comf'.ltmicated with the forward element since September or October

1967. The latest location of one(Station El) on 24 January 1968

in west-central Thua Thieu Province near 16-13N 107-17E (YC 452946)

represents a relocation of approximately 12 km from its December

operating area, near 16-16N 107-12E (YD 350000). Two

subordinates (Stations E2 and E3) appeared on the MR '11TIT

communications complex on 27 Novernber 1967 and 1 January 1968,

respectively. These stations are either in the process of

relocating, or have relocated within MR TTH: Station E2 was

initially located on 2 December 1967 near 16-15N 107-25E

(YC 591989) and SIGINT indicates that this station is now in the

process of relocating; 2 Station E3, initially located in SIGINT

on 11 January 1968 near 16~15N 107-15E (YC 408970), has been I

moving in a southeasterly direction, and is currently located

near 16-lJ.N 107-32E (YC 729900). Fl, first observed in

communications on 1.6 January 1968, is currently located near

16-18N 107-19E (YD 472037) as of 20 January 1968. However,

tenuous SIGINT indicates that this entity initiated communications

with Hq, MR TTH and the forward element as early as November 1967,

utilizing the watch facility. The forward element also

maintains communications with HC via both the watch and command

media, and with Hq, MR 4 (INN); Hq, DMZ Front; and several

unidentified stations on the watch commtmications net.

3

.Clf Fft ff I .C AVT lrc

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C. Possible Hue Municipal Unit

The current communications posture of the Hue Municipal

Unit includes the hea.dq_uarters and two subordinates, one of

which is the tentative !J0l~th Batta.lion. The second (Station Al)

is an unidentified entity formerly o. subscriber on the Hq, HR T'fH

net used for communicating with subordinates of the PAVN 6th

Regiment. The Hue Municipal Unit and its unidentified subordinate

( Station Al ) also maintain communications with Hq_, MR 'l'TH and the

forward element.

D. Tentative PAVN 4th Regiment

PAVN 4th Regiment communications consist of the regimental

headquarters, which maintains communications with Hq, MR TTH; the

forward element, and three subordinates, two of which (Stations Bl

and B2) were first observed during the latter part of 1967; the

third (Station B3) was first observed during January 1968. This

4th Regiment was formerly identified as serving the possible Thua

Thien Provincial Unit; however, the current communications posture

and area of operations, supported by collateral, permitted the

tentative identification of this unit as the PAVN 4th Regiment. 3

E. Possible PAVN 9th Regiment

Hq_, PAVN 9th Regiment currently communicates with Hq_,

MR TTH, the forward element, and one unidentified subordinate

(Station Cl). Communications emanating from the regimental

headquarters during December 1967 tenuously indicated that one,

possibly two, other subordinates were in existence; this evidence

however, remains unconfirmed.

F. Hq, PAVN 6th Regiment

The Hq, PAVN 6th Regiment communicates with one unidentified

battalion (Station Dl). In addition, the possible 802nd Battalion

and an unidentified, possible battalion were also communications

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s ubordina;tes of the PA.VN 6th Regiment during late 1967, but SIGINT

cannot c:onf'irm the subordination of these battalions t o the

6th Regiment. Hq_, PAVN 6th Regiment maintains direct communications

with both Hq, MR 'l"rII and the forward element.

7.. 3/0/S'1'Y/R20-68 .

2. 2/c11/vcM/R164-6G.

3. 2/o/vcM/R16-68.

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(A) 11 Hue Mncp

TJnit 16-18N l 1i17-<4:i

(YD 745¢41;

* * 804th Dr,

16-15N 107-45E (YC 956977)

* .) * ~ U/I Sta

Al

16-25N 1.// ... ::, f;':: (YD 606~71)

Vietnamese Communist units in Military Region Tri-Thien-Hue

l6-25N 107-2yjE (YD 1 1 0

(B) ! Hq, PAVN 4th Regt

1tz~1~4~~i516E

u/r Sta Bl

U/I Sta B2

l 9-l2N 107-57E , zc l 7;J93¢)

U/I Sta B3

16-lSN 10,7-34E (YD 754¢36)

U/I Sta B4

(C) * Hq, PAVN 9th Regt

16-34N 107-7,l8E (YD 289342)

u/r st.1 Cl

16-39N 1¢7-¢5E (YD 231434)

(D)} Hq, PAVN 6th Regt

16-3¢N 107-14E (YD 395254)

U/I Bn Sta Dl

16-32N 107-¢8E (YD 376301)

£~9~ This diagram depicts apparent unit subordination only.

* Direct communications with Hq , MR TTH

*{} Direct comtaunications with Tent Fwd Ele , Hq, J,ffi TTH

(E) tf U/I Sta

El 16-13N 107-17E

(YC 452946)

I U/I Sta

E2

l6-l4N 1¢7-23E (YC 565969)

* U/I Sta E3

16-llN 107-32S (YC 72990¢)

* U/I Sta

E4

16-46N l p6-46E (XD 885547)

* * U/I Sta

F'l

16-18N 10.7-19E (YD 472¢37)