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Flashcards in perceptual errors Deck (22)
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spacial orientation uses

vestibular equilibrium



massive role in flight safety
very persuasive
leads to spatial disorientation


2 routes when perceiving & making decisions before taking actions

1: when manual flying actions taken before consciously known and instant feedback
2: when making operational decisions you consider all the info available before taking action


3 types of illusions

kinaesthetic (proprioceptive)



difference from what you perceive and what is true


main factors for visual illusions

shape constancy
size constancy
arial perspective
auto-kinesis (auto kinetic illusion)- stare at point for long time and everything else moves
vertical false horizons- eg sloped ground or sloped clouds


up & down slope illusions on approach

up slope- perceive to be high, pitch down, realise and undershoot or come in too flat
down slope- perceive to be low, pitch up, realise, steep & overshoot, early flare


narrow and wide runway illusion

narrow- perceive to be high, pitch down, realise and undershoot or Coe in too flat
wide- perceive to be low, pitch up, realise, steep & overshoot, early flare


black hole effect

lights very bright when surrounded by nothing
think you're too close
pitch down
shallow approach, undershoot


weather conditions illusions

haze or fog- reduces detail so think we are further away tendency to be high on approach
rain on windscreen- refraction- runway looks lower- pitch down then have flat approach
daytime- rain makes us appear slow- thrust - increase LD
night - rain makes us appear fast- reduce thrust- stall


perceptual set

way we perceive things based on expectations
perceive some parts but may ignore others
affected heavily by past experience
motivation plays part
based around expectancy bias


kindastethic illusions

proprioceptors detect joint position- contribute to kindastethic
known as seat of your pants
very unreliable
e.g could think you're upright even if you're upside down


vestibular illusions: linear acceleration

somotogravic illusion
acceleration- hairs forced back and so is liquid. same way it would if tilted head back
illusion of pitch up- may want to pitch down, terrain, other aircraft may be a danger


vestibular illusions: angular accelerations

somatogyral illusion (the leans)
occurs when:
turn so gentle recovery doesn't have stimuli above sensory threshold
turn is so prolonged that the liquid & hairs stabilise so when turning out feels hairs move again and you think you're moving so the pilot corrects back even though you've rolled level
worst case can lead to graveyard spin- pilot attempts to recover from a spin re enters the spin


vestibular illusions: Coriolis illusion

most dangerous vestibular illusion
caused by sudden head movements when manoeuvring
become disorientated when we stimulate more than one canal at a time
mixed sensation
don't know what aircraft is doing and lose control
can cause vertigo


§vestibular illusions: vertigo

disorientation, dizziness cause by Coriolis and many other things
flicker vertigo- caused by certain light conditions, ie, sun through a prop, aircraft lights shining off cloud. similar to epilepsy


auditory illusions

hear something that's not there or different to what's been said


avoid / recover from illusions

pre flight planning
comprehensive briefings
keep good cross check of instruments
look to horizon
minimise head movements
co-ordinate with crew
follow SOPs


mid air collisions

head to head- aircraft look very small and far away until very last second
due to the saccade of the eye
aircraft that are not collision risk will move across fuel of view and easy to see
both turn right to avoid


motion sickness

occurs when a mismatch between visual, proprioceptive and vestibular systems
brain confused and leads to sickness, may think you have poisoning - vomiting
can be triggered by vibration


motion sickness symptoms

pale skin
cold sweat
increase in saliva
nausea & vomiting
apathy - lack of care/ interest


motion sickness treatment

close eyes or focus elsewhere (horizon)
minimise head movements
get fresh air
stay calm & relaxed
avoid alcohol & heat, gassy meals