Cognition in Aviation

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Cognition in AviationCognition in Aviation

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What is up and down ?What is up and down ?

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The sensesThe senses

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The Human Eye in AviationThe Human Eye in Aviation

The most important sense In aviation is the The most important sense In aviation is the sightsight..

The experience of visual illusions is The experience of visual illusions is therefore of great importancetherefore of great importance


Travel in air can distort the sense organs Travel in air can distort the sense organs and give rise to wrong perception of and give rise to wrong perception of

reality reality (=> wrong mental model)(=> wrong mental model)

You will bee victim ofYou will bee victim of

ILLUSIONSILLUSIONS

Spatial disorientationSpatial disorientation (the pilot is disoriented, he cannot determine aircraft position

typically affection perception of attitude, pitch and roll (= loss of situational awareness)


Some examplesSome examples

More than 200 illusions exist, More than 200 illusions exist, most of discovered in the most of discovered in the

1800 century1800 century







CafCaféé wall illusionwall illusion


PonzoPonzo illusionillusion


MMüüllerller--LeyerLeyer illusionillusion


Geometrical IllusionGeometrical Illusion






Illusion in depthIllusion in depth


Illusion in depthIllusion in depth


Illusion in concave and convexIllusion in concave and convex

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The Gestalt theory of The Gestalt theory of perceptionperception

Our perception and Our perception and ““mental modelmental model”” is is not only a result of sensory stimulation not only a result of sensory stimulation but also the but also the individuals standardsindividuals standards of of

the world. the world.


The Gestalt lawThe Gestalt law’’s of perceptual s of perceptual organizationorganization

ProximityProximityContinuityContinuitySimilaritySimilaritySymmetrySymmetrySimplicitySimplicityClosureClosure

∓∓Thoughts (what the brain thinks is hidden)Thoughts (what the brain thinks is hidden)

Bee ware of your whishes and desires


The brain will fill in missing parts The brain will fill in missing parts according to previous experience according to previous experience

and expectation and expectation (wishes or desires)(wishes or desires)

P y P y olol g g stst..Psychologist Physiologist


Negative pictureNegative picture

An example of adaptation of sensory cells in the retina

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Spatial orientationSpatial orientation

SEAT-OF-THE-PANTS

VISION VESTIBULAR

ORIENTATIONAND

BODYRESPONSES

SENSES OFBALANCE



SEAT-OF-THE-PANTS

VISION VESTIBULAR

ORIENTATIONAND

BODYRESPONSES

SENSES OFBALANCE


Human VisibilityHuman VisibilityVisibility: how well human eye can seeVisibility: how well human eye can seeContrast is key factor Contrast is key factor (better than luminance)(better than luminance)

Implications for aviation: Implications for aviation: –– Ability to recognize hazards is degradedAbility to recognize hazards is degraded–– Ability to steer unaffectedAbility to steer unaffected

““Black HoleBlack Hole”” approaches at night:approaches at night:–– Area under aircraft dark, featurelessArea under aircraft dark, featureless–– Pilots overestimate altitude, fly too low Pilots overestimate altitude, fly too low ⇒⇒ AWARENESS! AWARENESS!

Bad combination


Effects of Lighting on PerformanceEffects of Lighting on Performance

Too much light may produce GLARE:Too much light may produce GLARE:Direct Glare: light sources in field of Direct Glare: light sources in field of viewviewReflected Glare: reflected by surface in Reflected Glare: reflected by surface in field of viewfield of viewDiscomfort Glare: produces Discomfort Glare: produces discomfort, but does not necessarily discomfort, but does not necessarily interfere with performanceinterfere with performanceDisability Glare: reduces performanceDisability Glare: reduces performanceBlinding Glare: no object can be seenBlinding Glare: no object can be seen


Visual IllusionsVisual Illusions

Because of mBecause of misinterpretation of isinterpretation of sensory datasensory dataUnavoidable during ambiguous, Unavoidable during ambiguous, obscured or absent visual cues obscured or absent visual cues (=night)(=night)

AUTOKINESISAUTOKINESISStatic light appears to move when Static light appears to move when stared at in the dark; reduced by stared at in the dark; reduced by visual scanningvisual scanning



WATERFALL EFFECT WATERFALL EFFECT Rotor downwash gives false cue of climbRotor downwash gives false cue of climbHEIGHT ILLUSIONHEIGHT ILLUSIONFlying over low contrast, illusion of high altFlying over low contrast, illusion of high altFLICKER VERTIGOFLICKER VERTIGOFlicker between 4Flicker between 4--20 cycles/sec20 cycles/secSIZESIZE--DISTANCE ILLUSIONDISTANCE ILLUSIONViewing light as changing in brightnessViewing light as changing in brightness



RELATIVE MOTIONRELATIVE MOTIONMistake another aircraftMistake another aircraft’’s movement for s movement for ownown

FALSE HORIZONFALSE HORIZONCloud formations may be confused with Cloud formations may be confused with horizon or groundhorizon or ground

GROUNDGROUND--LITE MISINTERPRETATIONLITE MISINTERPRETATIONConfusion of ground lights with starsConfusion of ground lights with stars



SEAT-OF-THE-PANTS

VISION VESTIBULAR

ORIENTATIONAND

BODYRESPONSES

SENSES OFBALANCE


The vestibular senseThe vestibular sense


Orientation in space of the SemiOrientation in space of the Semi--circular Canals and circular Canals and OtolithsOtoliths


SemiSemi--circular Canals in relation to circular Canals in relation to aircraft movementsaircraft movements


Sensitivity of vestibular apparatusSensitivity of vestibular apparatus

SemiSemi--circular canals:circular canals:xx--axe: 2axe: 2oo/sec/sec22

yy--axe: 7axe: 7oo/sec/sec22 for climb for climb 44oo/sec/sec22 for divefor dive

zz--axe: 2axe: 2oo/sec/sec22

OtolithOtolith organ:organ:xx--axe 0,1 m/secaxe 0,1 m/sec22

zz--axe 0,1 m/secaxe 0,1 m/sec22

Note: the leans



SEAT-OF-THE-PANTS

VISION VESTIBULAR

ORIENTATIONAND

BODYRESPONSES

SENSES OFBALANCE


The The ““seatseat--ofof--thethe--pantspants”” sensesense

FORCE OF GRAVITY

GRAVITYPLUS

CENTRIFUGALFORCE

In flight, however, In flight, however, GG--forces combine forces combine with the pull of with the pull of gravity to make the gravity to make the seatseat--ofof--thethe--pants pants sense completely sense completely unreliable as an unreliable as an attitude indicator.attitude indicator.


Vestibular illusions during flight:Vestibular illusions during flight:TerminologyTerminology

SomatogyralSomatogyral illusion illusion (an erroneous sensation of (an erroneous sensation of rotation)rotation)OculogyralOculogyral illusion illusion (an erroneous visual (an erroneous visual experience of rotation in opposite direction)experience of rotation in opposite direction)SomatogravicSomatogravic illusion illusion (an erroneous perception (an erroneous perception of horizontal or vertical movement)of horizontal or vertical movement)OculogravicOculogravic illusion illusion (an erroneous visual (an erroneous visual experience of the horizontal or vertical movement)experience of the horizontal or vertical movement)

Vestibular illusions appear only under conditions wherethe pilot is deprived of sufficient outside visual cues


OculogravicOculogravic and and oculogyraloculogyralillusionsillusions

OculoOculo = eye= eyeGravicGravic = gravidity= gravidity

GyralGyral = gyro= gyro


Any event appearing during flight, Any event appearing during flight, where the pilot experience a false where the pilot experience a false

percept of his own percept of his own

SPATIAL DISORIENTATIONSPATIAL DISORIENTATION

Peripheral type:Correct interpretation of

insufficient sensory data

Central type:Erroneous interpretation of

correct sensory data

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False perception of Aircraft orientation

Correct perception ofAircraft orientation

Type I disorientation(unawareness of error)

Type II disorientation(awareness of conflicting input)

Control based on False perception

Inappropriatecontrol Loss of control

Aircraft accident

Conflict not resolved

Resolved

Correct control

Disorientation stress

Performance ↓

Error recognized


Critical and non critical phases of flight Critical and non critical phases of flight with respect to medical with respect to medical incapitationincapitation


Illusions when Illusions when taxyingtaxying

Relative movementRelative movement-- Feeling of relative movement of an object near to the Feeling of relative movement of an object near to the aircraftaircraft

-- Blowing snow (tailwind Blowing snow (tailwind ⇒⇒ speed impressionspeed impression↓↓ and and headwind headwind ⇒⇒ speed impressionspeed impression↑↑))

Cockpit height above the ground Cockpit height above the ground -- Higher cockpit Higher cockpit ⇒⇒ speed impression speed impression ↓↓


Illusions on takeIllusions on take--offoff

SomatogravicSomatogravic illusionillusion


SomatogravicSomatogravic illusion during takeillusion during take--offoff

Impression by pilot


Illusions on takeIllusions on take--offoff

SomatogravicSomatogravic illusionillusionOutside referencesOutside references


VectionalVectional false horizonfalse horizon


The The ““lean on the sunlean on the sun””

SUN


Ground lightGround light


Over waterOver water

Lights of fishing boats


Other Other vectionalvectional false horizonsfalse horizons

Gently sloping terrainGently sloping terrainSloping of ground up/down after takeSloping of ground up/down after take--offoff


Illusions in the cruiseIllusions in the cruise

AutokineseAutokinese

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AutokinesisAutokinesis



AutokineseAutokineseVertical Separation Vertical Separation (ex. approaching aircraft)(ex. approaching aircraft)

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Objects in distance appear in the Objects in distance appear in the upper visual fieldupper visual field



AutokineseAutokineseVertical Separation Vertical Separation (ex. approaching aircraft)(ex. approaching aircraft)

Holding (Holding (somatogyralsomatogyral illusion / illusion / CoriolisCoriolis))


SomatogyralSomatogyral illusion ex. during illusion ex. during holding patternholding pattern

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CoriolisCoriolis illusionillusion

Can occur when the head is tilted during a Can occur when the head is tilted during a longlong--established turning.established turning.The experience is an illusion of roll, often The experience is an illusion of roll, often accompanied by accompanied by dissinessdissiness

DEMO


Approach and landingApproach and landing

The phase in flight related to most The phase in flight related to most accidents (50%) and 73% of human accidents (50%) and 73% of human

errorerror

Initial judgement of glideslopeInitial judgement of glideslopeMaintenance of the glideslopeMaintenance of the glideslopeGround Proximity judgementGround Proximity judgement

Judgement of :

-distance

-height

-speed

VISUAL CUES


External visual cuesExternal visual cues

You can not use binocular cues in You can not use binocular cues in perception of relative depth, in perception of relative depth, in

state you must relay onstate you must relay on


Size and shapeSize and shape


Changing perspectiveChanging perspective


Movement of object in the Movement of object in the parafovealparafoveal and peripheral visual fieldand peripheral visual field


Initial judgement of Initial judgement of appropriate glideslopeappropriate glideslope


Visual angel (3Visual angel (3oo))

The aircraft generally have a fairly stable pitch attitude during approach ⇒

The horizon and visual touch-down point have stable locations within the visual framework of the canopy


Sloping groundSloping ground

If the terrain slopes down to the runway, the If the terrain slopes down to the runway, the pilot will perceive himself to be too low on pilot will perceive himself to be too low on approachapproachIf the terrain slopes up to the runway, the If the terrain slopes up to the runway, the pilot will perceive himself to be too high on pilot will perceive himself to be too high on approachapproach


An An upup--slopingsloping runway can create the runway can create the illusion that the aircraft is higher than it illusion that the aircraft is higher than it actually is, leading to a actually is, leading to a lowerlower approachapproach


A A downdown--slopingsloping runway can create the illusion that the runway can create the illusion that the aircraft is lower than it actually is, leading to a aircraft is lower than it actually is, leading to a higherhigher

approachapproach


Width of runwaysWidth of runways

A narrow runway may give A narrow runway may give the impression of being too highthe impression of being too high

A wider than normal runwayA wider than normal runwaymay give the impression of may give the impression of being too lowbeing too low


Black hole effectBlack hole effectAbsents of visual cues other than Absents of visual cues other than

airfield lights may give an illusion of airfield lights may give an illusion of being too high being too high ⇒⇒ too low approachtoo low approach


Atmospheric PerspectiveAtmospheric Perspective

Incorrect distance calculation because Incorrect distance calculation because of clarity of atmosphereof clarity of atmosphere

(interference of fog, rain, smoke or (interference of fog, rain, smoke or snow)snow)

Errors of perception can occur when ground features are atypical

(small trees)


Maintenance of the glideslopeMaintenance of the glideslope

When using fix position on the windshield When using fix position on the windshield beeingbeeing unaware of speed loss + altitude can unaware of speed loss + altitude can lead to the impression of being on glideslope lead to the impression of being on glideslope

when actually too low when actually too low


Texture and texture flowTexture and texture flow


Ground Proximity judgementGround Proximity judgement(Assessment of height by cues)(Assessment of height by cues)

Apparent speed of objects on the ground Apparent speed of objects on the ground will increase as the height reduceswill increase as the height reducesSize of objects will increase with decreasing Size of objects will increase with decreasing distancedistanceApparent width of the runway will increaseApparent width of the runway will increaseTexture of the ground will changeTexture of the ground will change


Wheels and touch down pointWheels and touch down point

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Coning of attentionConing of attention

Specially in the student pilotSpecially in the student pilotDuring stress and high workloadDuring stress and high workload

Restriction of the field of attention


Missed ApproachMissed Approach

SomatogravicSomatogravic illusionillusionOculogravicOculogravic illusionillusion

Response to linear acceleration


SomatogravicSomatogravic illusion during forward illusion during forward accelerationacceleration

Performing a 0.5 G forward acceleration will result in a 30o pitch-upsomatogravic illusion provided that there are no visual cues

indicating the position of the horizon.


OculogravicOculogravic illusion during forward illusion during forward accelerationacceleration

If there is a weak, distant , non-horizon-like visual cue, the pilot willperceive a similar upward movement of the object when experiencing

his somatogravic pitch-up illusion: an oculogravic illusion.


Recorded flight path and calculated force Recorded flight path and calculated force (weight) vector of an aircraft that crashed (weight) vector of an aircraft that crashed

after initiating an overshootafter initiating an overshootLinear acceleration Radial acceleration


Remember the potential danger of Remember the potential danger of being in a being in a ““high arousal statehigh arousal state””

Prone to spatial disorientation despite trainingProne to spatial disorientation despite trainingBeing unable to interpret the cockpit instrumentsBeing unable to interpret the cockpit instrumentsDegradation of performanceDegradation of performanceFunneling of attention of focusFunneling of attention of focusRegressionRegressionMental Mental ““blockingblocking””Mood swingsMood swingsRestlessnessRestlessnessTremblingTremblingPanicPanic


Protective measures against illusionsProtective measures against illusionsThe use of The use of organisedorganised and formal training to and formal training to

recogniserecognise::

Illusions are natural phenomenaIllusions are natural phenomenaThe different types of illusionsThe different types of illusionsThe use of other visual cues for informationThe use of other visual cues for informationThe need for flight briefingsThe need for flight briefingsSpecial care needed during accelerationsSpecial care needed during accelerationsThe effect of head movements, fatigue, night an The effect of head movements, fatigue, night an other conditions with reduced visibilityother conditions with reduced visibilityThe need of protection provided by manufacturers The need of protection provided by manufacturers


How to cope with spatial How to cope with spatial disorientation when it disorientation when it

occurs in flightoccurs in flight


DonDon’’t flyt fly

DrugsDrugsExhaustionExhaustionAlcoholAlcoholTobaccoTobaccoHypoglycemiaHypoglycemia


Make a positive effort to redirect Make a positive effort to redirect attention to other aspects of the attention to other aspects of the

flying task flying task (ex. a quick shake of the head)(ex. a quick shake of the head)


When you are suddenly confronted by strong When you are suddenly confronted by strong illusory sensations or difficulties in establishing illusory sensations or difficulties in establishing orientation and control of the aircraft:orientation and control of the aircraft:

Get on to instruments, check and crossGet on to instruments, check and cross--check, check, ensure good instrument illuminationensure good instrument illuminationMaintain instrument reference and correct scan Maintain instrument reference and correct scan pattern, watch your height at all timepattern, watch your height at all timeControl the aircraft in such a way as to make the Control the aircraft in such a way as to make the instruments display the desired flight configurationinstruments display the desired flight configurationDo not attempt to mix flight by external visual Do not attempt to mix flight by external visual reference with instrument flight until external visual reference with instrument flight until external visual cues are unambiguouscues are unambiguousSeek help if severe disorientation persists. Hand Seek help if severe disorientation persists. Hand over to coover to co--pilot, call ground controller and other pilot, call ground controller and other aircraft, check altimeteraircraft, check altimeter


Remember:Remember:Nearly all disorientation is a normal Nearly all disorientation is a normal

response to the unnatural response to the unnatural environment of flight. If you have environment of flight. If you have been alarmed by a flight incident been alarmed by a flight incident

discuss it with colleagues including discuss it with colleagues including your flight surgeon.your flight surgeon.

Your experience will probably not be Your experience will probably not be as unusual as you thoughtas unusual as you thought


Collision and the retinal imageCollision and the retinal image

The danger if a closing aircraft The danger if a closing aircraft remains on the same spot on the remains on the same spot on the windscreen windscreen ⇒⇒ it is maintaining a it is maintaining a Line of Constant Bearing (LCB)Line of Constant Bearing (LCB)

and a collision risk existsand a collision risk exists


In Night remember the Night Blind In Night remember the Night Blind SpotSpot

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ExampleExample

Two jet aircraft converging at normal Two jet aircraft converging at normal crusingcrusingspeeds of 550 KIAS each.speeds of 550 KIAS each.Closure rate of approx. 18 miles/minuteClosure rate of approx. 18 miles/minuteReaction time is 5Reaction time is 5--12 sec. to take action12 sec. to take action⇒⇒ Recognition distance of 1,5 Recognition distance of 1,5 –– 3,8 miles3,8 milesAt this distance the aircraft will appear smallAt this distance the aircraft will appear smallAnd it will be difficult to see due to lack of And it will be difficult to see due to lack of relative motionrelative motion


Retinal size of closing aircraftRetinal size of closing aircraft

Minimum visual angel for detection:

0,2o


Visual angle of a 40Visual angle of a 40--ft wide aircraft ft wide aircraft closing at constant velocityclosing at constant velocity

Time to see and avoid


Midair collision by constant angel Midair collision by constant angel and speedand speed


The seeThe see--andand--avoid concept has physical and avoid concept has physical and behavioral limitations such that pilots cannot behavioral limitations such that pilots cannot

reliably see and avoid conflicting aircraftsreliably see and avoid conflicting aircrafts


Vision and Midair CollisionsVision and Midair Collisions

Three most common midThree most common mid--air collisions:air collisions:Head onHead onConverging from side Converging from side Climb/descentClimb/descent


Saccade of the eyeSaccade of the eye

Eyes move in series of jerks and Eyes move in series of jerks and each movement is followed by a each movement is followed by a

rest period of 1/3 secondrest period of 1/3 second


The most successful scanning The most successful scanning technique:technique:

Each movement should be of 10Each movement should be of 1000 with 2 seconds restwith 2 seconds restAirspace above and below must be coveredAirspace above and below must be coveredThe sky should be covered in overlapping sectors of about The sky should be covered in overlapping sectors of about 101000

Peripheral vision can be vital in spotting collision threats in Peripheral vision can be vital in spotting collision threats in movementmovementMove the body and head around physical obstructionsMove the body and head around physical obstructionsSpecial care during takeSpecial care during take--off, landing, ascent and descentoff, landing, ascent and descentAction immediately if another aircraft shows no lateral or Action immediately if another aircraft shows no lateral or vertical movements (LCB) and is increasing in size.vertical movements (LCB) and is increasing in size.


Special situationsSpecial situations

Rain on windscreenRain on windscreen


Special situationsSpecial situations

Rain on windscreenRain on windscreenFlying over smooth waterFlying over smooth waterSnow coverageSnow coverage““White outWhite out””Fog and pollutionFog and pollutionRunway lightsRunway lights

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Cognition in Aviation