jfk flight

22 flight safety australia, november-december 1999

New York City

CRASH SITE

30km

Martha’s Vineyards

Hyannis

Essex County Airport

What killed JFK Jr?What killed JFK Jr?

John Floggedtotal fl

Lessons for VFR pilots.

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flight safety australia, november-december 1999 23

Staff writer s

AT 9.41PM ON FRIDAY 16July a Piper Saratoga crashedoff the coast of Martha’sVineyard, Massachusetts.Onboard were three ofAmerica’s most recognised

and admired celebrities – John F. KennedyJr, his wife Carolyn, and her sister LaurenBessette. All were killed on impact.

Within 24 hours the tragedy was the leadstory in newspapers and on televisionsaround the world. The ensuing speculationand commentary centred on the hazards ofvisual flight at night and the pros and consof light aircraft travel.

Was this another case of a VFR pilot losingcontrol after flying into instrument meteo-rological conditions (IMC)? Did Kennedysuffer an incapacitating medical event beforethe crash? Could he have experienced aninstrument failure? The investigation into theaccident by the US National TransportationSafety Board (NTSB) is continuing.While thepreliminary report was released shortly afterthe accident, at this point, the NTSB has notdrawn any conclusions about the factorsinvolved in the causes of the accident. Evenafter the final report is released, it’s possiblethat some questions will remain unanswered.

However, the fact that this issue has beenthe subject of widespread speculation bothin the general community and, more impor-tantly, among private pilots, suggests that adiscussion about the challenges of visualflight at night is both timely and pertinent.

Discounting the tragic outcome, itappears there was nothing terribly remark-able about Kennedy’s flight. According tothe NTSB’s preliminary report, night visualmeteorological conditions prevailed forthe flight which originated at Essex CountyAirport, New Jersey, and was intended tocontinue to Martha’s Vineyard Airport todrop off one passenger before continuingto Hyannis, Massachusetts.Conditions: The Hyannis forecast was for

winds from 230 degrees at 10kt, visibility 6miles, and sky clear; with winds becoming280 degrees at 8kt. No AIRMETs or SIGMETswere issued for the route of the flight, andall airports along the route reported visualmeteorological conditions.

According to October 1999 issue of AOPAPilot, the magazine published by the USAircraft Owners and Pilots Association, the9.53pm METAR from Martha’s Vineyardsuggested good VFR conditions at theairport. Visibility was 10 miles, and thewind was 10kt from 240 degrees.

No cloud was forecast and “the tempera-ture-dewpoint spread was six degrees –outside the normal range for fog”. However,nearby boaters around the time of the crashreported poor visibility due to a heat-wavehaze which was affecting much of the eastcoast of the US. This was substantiated byother pilots in the area who also reportedreduced visibility.

The flight from Essex County toMartha’s Vineyard and on to the familycompound at Hyannis was a familiar onefor Kennedy who gained his private pilot’slicence on 22 April 1998. Kennedy hadtrained in Piper Warriors and Arrowsbefore purchasing the 1995-model PA-32R-301 Saratoga in April this year. At thetime of the accident he had logged around300 hours of flight time and is alsoreported to have started training for aninstrument rating – this has not beenconfirmed by the NTSB.NTSB preliminary report: Kennedy toldthe Essex County Airport tower controllerthat he would be proceeding north of theTeterboro Airport, and then eastbound.There is no record of any further commu-nications between Kennedy and air trafficcontrol. The NTSB preliminary report saysthat radar data shows the aircraft passednorth of the Teterboro Airport, and thencontinued northeast along the Connecticutcoastline at 5,600ft, before beginning tocross Rhode Island Sound near PointJudith, Rhode Island.

A review by the NTSB of the radar datarevealed that the aircraft began a descentfrom 5,600ft about 34 miles from Martha’sVineyard. The airspeed was about 160kt,and the rate of descent was about 700 feetper minute (fpm).

At about 2,300ft, the aircraft began aturn to the right and climbed back to2,600ft. It remained at 2,600ft for aboutone minute while tracking on a south-easterly heading. The aircraft then startedanother descent of about 700fpm and aleft turn back to the east. Thirty secondsinto the manoeuvre, the aircraft startedanother turn to the right and entered arate of descent that exceeded 4,700fpm.

enned y Jr hadbout 300 hour st time .

NTSBIdentification: NYC99MA178

Accident occurred: JUL-16-99

at VINEYARD HAVEN, MA

Aircraft: Piper PA-32-R301

Registration: N9253N

Injuries: 3 Fatal


PRIVATE OPERATIONS

The altitude of the last recorded target was1,100ft. It was 9.40pm on Friday.

The following Tuesday the wreckage ofthe Saratoga was located in 116ft of water,about 1/4 of a mile north of the 1,100ftradar position.

The engine, propeller hub and blades, andentire tail section were recovered. The entirespan of both main wings’ spars were alsorecovered, as well as 75 per cent of the fuse-lage/cabin area, 80 per cent of the left wing,and 60 per cent of the right wing.

The NTSB’s preliminary report states that“examination of the wreckage revealed noevidence of an in-flight structural failure orfire. The right wing structure exhibitedgreater deformation than the left. Two of thethree landing gear actuators were recoveredand found in the fully retracted position.

“There was no evidence of conditionsfound during examinations that would haveprevented either the engine or propeller fromoperating.Visual inspection of the propellerindicated the presence of rotational damage.Detailed examination of the navigation andcommunication radios, autopilot andvacuum systems are planned for a later date.”Disorientation? Speculation that Ken-nedy’s fatal accident was caused by disori-

entation and subsequent loss of control isbased on the fact that the flight was madeover featureless terrain at night and thepossibility that the horizon could have beenobscured by haze. While there is not enoughevidence to suggest that spatial disorienta-tion or visual illusions played a part in theevents of 16 July, the accident has causedsome aviators to suggest there is insufficientawareness among VFR pilots about thehazards of night flight.

“Regardless of what caused the Kennedyaccident,” wrote columnist Barry Schiff inthe September 1999 issue of AOPA Pilot,“speculation about it seems to indicate thatflight training should place greater emphasison the imperative need for VFR pilots tomaintain visual reference to the ground or toa horizon during VFR night operations. If apilot departs a shoreline or heads into thedesert and discovers that these references do

not exist, he or she should have been trainedto recognize the need to reverse courseimmediately and return to those visual refer-ences left behind.”

“In some cases, flying at night withoutsufficient references can be more hazardousthan inadvertently flying into cloud,” hecontinues.“Cloud penetration usually trig-gers a conditioned response bred of goodtraining. The VFR pilot knows to reversecourse and exit the cloud without hesita-tion. Losing visual reference at night doesnot stimulate such decisiveness, because theloss only develops more gradually.”

In the US in 1997, more than 80 per centof fatal GA weather-related accidents werecaused by visual flight into IMC. The fatalaccident rate was almost three times higherat night in IMC than during day VFR.

In Australia during the 1990s 26 fatalaccidents have been attributed to loss ofcontrol by VFR pilots flying into IMC. Morethan a quarter of those occurred at night.

John F. Kennedy’s death was tragic. Butthere is one positive outcome that maycome from the accident: greater awarenessamong visual pilots about the hazards ofnight VFR.

In the US in 1997, morethan 80 per cent of fatal GAweather-related accidentswere caused by visual flightinto IMC.

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9:33pm5,600ft

9:38pm2,300ft 9:40pm

2,250ft

9:39pm2,600ft

THE LAST 8 MINUTES9:33pmThe aircraft begins a descent from 5,600ft about

34 miles from Martha’s Vineyard. Radar data

indicates the airspeed is about 160kt and the

rate of descent is 700fpm.

9:38:20At about 2,300ft the aircaft begins a turn to the

right and climbs back to 2,600ft.

9:39:00The aircraft remains at 2,600ft for about one

minute while tracking on a southeasterly heading.

9:40:00The aircaft starts a descent of about 700fpm, and

makes a left turn back to the east.

9:40:30Thirty seconds into the manoeuvre, the aircaft

starts another turn to the right and enters a rate

of descent exceeding 4,700fpm.

9:41:00The aircaft crashes into the Atlantic, approxi-

mately seven-and-a-half miles southwest of Gay

Head, Martha’s Vineyard, Massachusetts.

9:41pmImpact

Descentappr oximatel y

700fpm

Descentgreater than

4,700fpm

Descentappr oximatel y

700fpm


FLYING AT NIGHT IS IN MANYrespects more challenging thanday VFR flight, for a variety ofreasons. Chief among these is thelack of good-quality outside visual

cues and the consequent increased risk ofvisual illusions and spatial disorientation.

There are many more hazards associatedwith night flight apart from the graveyardspiral, and JFK Jr’s accident serves as a timelyopportunity for reviewing these. As a pilot,the more you know and understand aboutthese hazards, the safer you are likely to be atnight.

Human beings are not designed for aerialoperations, either by day or by night. We canonly achieve this by the use of technologyand training. Our physiological limitationsbecome very evident under certain flightconditions, and the night environment isperhaps the most significant.

Night flying involves operating anaircraft with much poorer outside visualreferences than are available during the day.For that reason, our normal ability toorientate ourselves in space can become

impaired, with potentially catastrophicconsequences. Very strong illusions canresult, either visually-based or balanceorgan-based.

The temptation to respond to these illu-sions can be incredibly powerful, but loss of

control of the aircraft can readily occur ifthis is allowed to happen.

Which way is up? How do we orientateourselves? How do we know which way isup and what is happening around us? Undernormal conditions, we rely heavily on thecombined efforts of three major bodysystems: the eyes, the inner ear or vestibularsystem (balance organs) and the proprio-ceptive (seat-of-the-pants, or movementsensing) system. Of these three systems, theeyes account for the vast majority of orien-tation information (approximately 80 percent). The other two account equally for theremainder.

The visual system is thus a very powerfulorientation system. During the day, the eyeprocesses an incredible amount of informa-tion. Peripheral vision constantly providesinput to the brain of where the horizon is,and whether things are moving or not.Central vision gives very precise informa-tion about what you are looking at, be it thedistant horizon, ground features or aircraftinstruments.

The balance organs, comprising the

The hazards of night flight

Human beings are notdesigned for aerialoperations, either by day or by night. We can onlyachieve this by the use oftechnology and training. Our physiologicallimitations become veryevident under certain flightconditions, and the nightenvironment is perhaps the most significant.

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Kenned y’s Saratoga was equipped with a stormscope , three-axis autopilot and GPS.


PRIVATE OPERATIONS

semicircular canals and the otolith organs,are located in each inner ear. They accuratelytell the brain what angular (rotation) and/orlinear acceleration the body is beingsubjected to. When you turn your headaround to look behind you, the semicircularcanals tell the brain that the head is moving.The otoliths constantly tell the brain that itis at 1G, or that you are accelerating downthe runway on the take-off roll.

In reality, humans have no absolute senseof where they are. Our orientation system isdesigned to tell us where we are in relationto something else. Humans orientate them-selves with respect to a horizontal feature(the horizon or Earth’s surface) and avertical feature (the force of gravity).

Under normal conditions, we can main-tain a constantly updated, very accuratesense of our position or motion relative tothese two features. This works well whenyou consider that we have evolved tobecome fairly successful terrestrial creaturesoperating in a 1G environment.

However, when we take to the sky and goflying, we can change the goalposts signifi-cantly. We can operate independently of thehorizon and Earth’s surface, and we can

change the force of gravity that we aresubjected to. Our orientation mechanismshave not evolved at the same rate as aero-space technology, yet spatial disorientationis a frequent phenomenon in the flight envi-ronment.

Spatial disorientation: What is spatialdisorientation? It is defined as the failure tocorrectly sense your (or your aircraft’s) posi-tion, attitude or motion relative to theEarth’s surface and the force of gravity.Spatial disorientation is not always recog-nised. If pilots realise that they are disori-ented they are then in a position to at leastattempt to reorient themselves.

If they do not realise that they are disori-ented (unrecognised spatial disorientation)they are far more likely to have an accident,

as no attempt is made to rectify the abnormalsituation. Indeed, even when a pilot realisesthat he is suffering the effects of spatialdisorientation, recovery can still be difficult.

Spatial disorientation is a well-recognisedcause of aviation accidents. The UnitedStates Navy has reported that between 1980and 1989, some 112 major aircraft accidentsinvolved spatial disorientation of the crew.The United States Air Force for the sameperiod reported that spatial disorientationled to 270 major aircraft mishaps.

The problem is by no means limited tomilitary aviation. Spatial disorientation is avery real concern in the civilian aviationcommunity. In a 1994 report, the US FederalAviation Administration (FAA) found thatmany of the 1,000 domestic aviation acci-dents attributed to human error were causedby spatial disorientation.

Helicopter operations are also susceptibleto spatial disorientation. Between 1987 and1995, 291 major helicopter accidents in theUnited States Army were attributed to spatialdisorientation. These accidents accounted forthe loss of 110 lives and US$468,000,000 inmaterial costs.

Spatial disorientation is therefore a relatively

The United States Navyhas reported that between1980 and 1989, some 112 major aircraft accidentsinvolved spatial disorientationof the crew.

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Blac k hole illusion: The pilot on appr oach to an airfield at night with f ew surr ounding lights g ets the falseimpression of being too high. The tendanc y is to fl y an appr oach that is too lo w, with the dang er of under shooting.


common experience for both fixed-wing androtary-wing aircrew. The reported careerincidence of spatial disorientation in aircrewis in the range of 90 to 100 per cent. Ofperhaps greater significance is the findingthat experienced pilots are not immune fromthe effects of spatial disorientation.

It is a commonly held view that disorien-tation affects the junior, inexperienced pilot– this is not the case. Analysis of accidentsinvolving spatial disorientation suggests thateven highly proficient senior pilots aresusceptible to the effects of spatial disorien-tation.

The fundamental problem is that in theabsence of good external visual cues, oursense of orientation is provided by inputfrom the seat-of-the-pants and the inner earbalance organs. This 20 per cent contribu-tion is far less reliable than the more domi-nant visual system, and as such is far morelikely to give you a false representation ofwhat is going on. This is exactly the situationat night.

The outside visual world is dark andfeatureless. While there are often lights onthe ground, and in some cases moonlightavailable, the levels of light are generally lowand will be highly variable in quality,frequency and intensity. The higher you fly,the darker it becomes as you put a greaterdistance between you and any ground-basedlighting. With poor visual cues, you are farmore likely to become disoriented.Visual illusions at night: Your eyes stillwork at night, obviously, but they are farless effective. In the absence of a good setof outside visual references, your eyes willconcentrate on the few visual cues that areavailable. As such, there are a number ofvisual illusions that can occur at night.Because the visual system is so dominant(remember it accounts for 80 per cent ofour orientation information) theseillusions can be particularly powerful andquickly lead to disorientation and loss ofcontrol.

One of the common forms of night flyingillusion is ground light confusion. Imaginea scenario where you are flying on a clearnight over an area dotted with farmhouses.The lights at random intervals from theground can be confused with the stars above.Which way is up? A pilot can convincehimself that the farmhouse lights are starsand vice versa. Military aircraft have beenknown to fly inverted with the pilotcompletely happy that they are up the rightway. The experience of not knowing which isthe ground and which is the sky is verydisconcerting.

The black hole illusion can occur duringapproach to an airfield at night, when thereare few (if any) lights on the ground between

you and the threshold. This area appears tothe pilot as a black hole. The pilot unwit-tingly flies a lower approach than appro-priate, as if landing in the black hole. Theobvious endpoint to this illusion is landingshort of the runway, or hitting an unseenobstacle such as rising terrain. In most casesthe undershoot becomes apparent and theaircraft is recovered and landed, but there isclearly little margin for error in such circum-stances.

Yet another night visual illusion is theautokinesis phenomenon. Here, a singlepoint source of light appears to move atrandom around the visual field. It gives theimpression that the light source is movingwhen in reality it is fixed in place. The expla-nation for this is that your eyes are contin-ually moving, in order to expose differentparts of the retina to the incoming light. The

rods and cones in the retina that turn lightinto an electrical nerve signal to the braincontain photopigments that react to light.

If the eye remains perfectly still, a givennumber of cones, for instance, will be doingall the work. They will eventually run out ofphotopigments and will no longer generatea signal to the brain. In effect, the eye stopsworking. To prevent this, the eye isconstantly adjusted so that fresh cones arebrought into the picture (so to speak) whileother cones regenerate their photopigments.During the day, when the visual field is richwith detail and colour, these eye movementsare not apparent to the individual.

However, at night when the only thing tolook at is a single point source of light, theseeye movements give the individual theimpression that the light is moving, when infact it is the eyes that are moving. The autoki-

What killed JFK Jr?

As an aer oplane accelerates f orwar d after take-off , the somatogra vicillusion results in an o verwhelming sensation of pitc hing to a high-noseattitude .The illusion is pr oduced b y the otolith or gans in y our ear s whic hsense orientation.

Head tilted up

Forwar dacceleration

Impression:“I’m pitc hing

up”.

Head stationar y andupright, where theimpression is: “I’m

stationar y and upright. ”

The somatogra vic illusion


PRIVATE OPERATIONS

nesis phenomenon has led to aircraftattempting to formate on a star, thinking itwas another aircraft.Vestibular illusions: In the absence of goodvisual cues, the information from thevestibular system (balance organs) can bepotentially misleading. There are a numberof vestibular illusions, but we’ll examineonly the more important ones.

The somatogravic illusion is also knownas the dark night take-off or pitch-up illu-sion. The typical scenario is an aircraft ondeparture, accelerating down the runway. Itrotates, and shortly after is observed to pitchforward and fly at full power into theupwind threshold of the runway.

Why does this happen? The otoliths tellthe brain that acceleration down the runwayis occurring. In the absence of good visualcues, the brain interprets this as pitching up,made worse by aircraft rotation. The pilot,not wanting to stall at low-level, instinctivelypitches forward and flies into the ground.The whole sequence can take less than aminute.

Importantly, you don’t need to be flyingan afterburning fighter aircraft to get thisillusion.

The next timeyou fly as apassenger in acommercial jet,close your eyesduring the take-offroll and see if youget the sense ofpitching up. It is avery powerfulsensation, and hasled to the loss ofmany aircraft,both civil andmilitary.

The graveyardspin or spiralaffects the semicir-cular canals. Again, this occurs in theabsence of good visual cues. The semicir-cular canals are designed to register angularacceleration, but only if it exceeds a certainthreshold (approx 2°s2).A few unintentionaldegrees of bank (with the pilot head-downin the cockpit, for instance) leads to a spiraldescent.

If this descent occurs at a sub-thresholdrate of turn, or if constant velocity isreached, then the canals will not detect it.With no visual reference to tell it otherwise,the brain believes that it is still straight andlevel. If the pilot checks the instruments andrealises what is happening and recovers toactual straight and level flight, the canals willalmost certainly be given a big stimulus andregister the angular acceleration as the

aircraft recovers.The canals then give the temporary sensa-

tion of a turn in the opposite direction, oftenaccompanied by a short-lived series offlicking eye movements which makes scan-ning the instruments difficult. The desire tothen re-enter the original turn is very strongas this will cancel out the false sense of rota-tion. Given the difficulty in seeing, re-entering the turn is an easy thing to do.Veryquickly the pilot can get into a vicious cycleof turn, recover, turn, recover until groundimpact occurs.

The leans is a similar illusion, and is themost common example of disorientation.In this situation, the pilot recovers from afew degrees of unintentional bank, thusgiving the canals their first input. Havingrecovered, the pilot now feels the sensationof bank in the other direction. To resolvethe conflict, the pilot leans in the directionof the original turn, while flying straightand level.

Prevention of disorientation: One wayof preventing disorientation is to be awareof the many potential illusions and the situ-ations in which they can occur. Pre-flight

preparation is veryimportant. Forinstance, if you aregoing to take-off atnight, remember thedark night take-offillusion. At least thatway you’ll be preparedfor it if it happens.

You should only flywhen you are physi-cally and mentally fit.Flying with a cold willaffect your inner earbalance organs,making disorientationmore likely to occur.The same can be saidfor alcohol.

If you do get disoriented, what shouldyou do? The answer is to believe yourinstruments – they do not suffer the samelimitations that you do.

Clearly proficiency with instrument flightis essential. If disorientation occurs, get onyour instruments and make them readstraight and level (despite what your headmight be telling you) until the disorien-tating sensation has gone. If necessary (andif possible), hand over control to anotherpilot.

Flying at night can be a rewarding experi-ence, and can be done safely if you are awareof the unique hazards associated with it.

Article researched and written by James Ostinga,

Mark Wolff, David Newman, and Sue White.

Set your own standardsWhen are you too tired to conduct a safeflight? How do you judge if you are toostressed? Do you have sufficientexperience in the aircraft type you intendto fly? Personal minimums checklists arean easy way for pilots to determine whenthey should and should not fly.

A personal minimums checklist is a toolwhich is tailored to your level of skill,knowledge and ability. Checklist itemshelp you control and manage risk byquickly evaluating the internal andexternal pressures affecting flight safety.CASA’s personal minimums checklist usesfour categories, each with a number oftopics where you, the pilot, set theminimum conditions under which you feelcomfortable conducting a flight.Items to consider include:

Pilot• Experience/Recency (such as take-offs/landings, hours in make/model,instrument approaches and more)• Physical condition (including sleep,food and water, alcohol anddrugs/medication consumption in the last24 hours and more)

Aircraft• Fuel reserves (cross-country)• Experience on type• Aircraft performance• Aircraft equipment

Environment• Airport conditions• Weather• Weather for VFR

• Weather for IFR

External pressures• Trip planning• Diversion or cancellation alternate

plans• Personal equipmentPersonal minimums checklists should beused before every flight – you may besurprised how a quick glance before flightincreases your awareness of the pressures(some of which are very subtle) which canaffect your flying.

As a guide, be wary if you have an itemthat’s marginal in any single risk factorcategory. If you are exceeding any of yourpersonal minimums in two or more of theabove categories, don’t go! Pressureswhich seem negligible on the ground caneasily get out of control in the air.CASA has personal minimums checklists(for individuals) and kits (for flyingschools/organisations) available free ofcharge. To order, call 131 757 and ask forextension 1375.

The next time you fly as a passenger in acommercial jet, close youreyes during the take-off rolland see if you get the senseof pitching up. It is a verypowerful sensation, and has led to the loss of manyaircraft, both civil andmilitary.

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Stanle y N. Roscoe

IN THE PARLANCE OF FLIGHTinstructors and flight researchers, theterm “graveyard spiral” refers to anyhigh-speed spiral dive, as distin-guished from a “graveyard spin” inwhich the aircraft is actually stalled at

a low airspeed. A pilot can enter a grave-yard spiral in many different ways, butmost often the entry is subtle rather thanviolent. The spiral dive typically follows agentle, unnoticed entry into a banked atti-tude below the pilot’s threshold for angularacceleration.

The sensory nerves in the semicircularcanals of the inner ear are the receptorsthat provide inputs to our “sense ofbalance” that, among other services, keepsus from falling in the shower when we getsoap in our eyes. Because these sensorsrespond only to linear and angular accel-erations, they tell the brain nothingdependable about rates or positions, suchas roll rates and bank angles.

Furthermore, these sensors have rela-tively high thresholds, below which theydo not sense accelerations. As a conse-

quence a pilot can gradually enter a bankwithout feeling any change in aircraft atti-tude, and this is the most common begin-ning of a graveyard spiral.

When the pilot notices the banked atti-tude on the artificial horizon, several badthings can happen:• If the pilot makes the correct aileroninput to roll out of the bank and theresulting roll acceleration is above thepilot's threshold, the wings may belevelled, but the pilot will now “feel” thatthe aircraft is banked in the opposite direc-tion. This experience is known as having“the leans” because of the compelling urgeto lean in the direction of the original

banked attitude even though the wings-level attitude is maintained. If the illusionis overpowering, the pilot will often rollback into the original turn to restore afeeling of wings-level and becomeconfused, then totally disoriented.• If the pilot makes the incorrect aileroninput, as occasionally happens, the bankangle will start to increase, with the aircraftrolling farther away from wings-level witha consequent lowering of the nose and aloss of altitude. The pilot may be able tocatch this mistake immediately and makethe proper responses to recover, but notalways. The pilot may also try to stop therotation of the horizon bar by a hard-overrotation of the control yoke in the oppositedirection and pull back on the yoke to stopthe loss of altitude. This tightens the turnand steepens the dive.

Dr Stanley Roscoe is the senior vice president of Aero

Innovation, Inc. an aviation human factors

company based in Montreal, Canada.

For more information about horizon control

reversal and graveyard spirals, visit

www.casa.gov.au/fsa/


Anatomy of a graveyard spiralIn a steep bank, the

nose of the airplane drops,and it starts to lose altitude.To hold altitude the pilotpulls back on the wheel,which tightens the turn andsteepens the spiral dive.

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Flat spin Steep spin Spiral dive

Not to be confused with a spin, whic h occur s when one or both wings are stalled, a spiral dive is a steep descending turn – neitherwing is stalled and the air speed and rate of descent is high. The correct reco very fr om a spiral dive is to reduce po wer, roll the wingslevel, and g entl y raise the nose .

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