Spacial disorientation Flashcards
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What’s spatial disorientation ?
Pilot’s erroneous perception of position, attitude or motion in relation to gravitational vertical and the earth’s surface
how to define the difference from orientation illusion (gravitational + earth surface)
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What’s orientation illusion ?
False perception of position or motion caused by the misidentification of orientation information
What’s DVE
“Degraded visual enviroment”
brownout
Which flight conditions are most known for causing spatial disorientation ?
Hovering or flying at night with a lack of visual cues
What’s the 3 types of spatial disorientation ?
1 Unrecognized
2 Recognized
3 Incapacitating
What two “modes” does the visual system consist of and what are the used for ?
Focal vision ( object recongnition and identification, allows us to see colors )
Ambient (peripheral) vision ( Detect attitude, motion & cues - enviroment)
What’s the 3 systems intergrated to maintain equilibrium and balance ?
Visual, vestibular & somatosensory systems
Which sensory system get’s you into most trouble in aviation
Vestibular system
What’s the function of the vestibular system ?
Visual tracking
Moving head but eyes staying focused
Reflex information
Body reaction unconscious
orientation without vision
Walking to bathroom at night in the dark
What’s the functions of the semicircular canals ?
vestibular system
Detects change in both speed and direction
Detects yaw, pitch and roll
Contains fluid
What are the functions of the otolith organs
Change in speed without change in direction (tænk børster der tilter)
(stimulated by gravity and linear movements)
Which type of inertia force is the otolith organs sensitive to ?
Linear (change in speed)
What’s the somatosensory system
The system that reactes to sensations resulting from force or pressure (skin, muscels ect.)
Why can’t you rely only on the somatosensory system ?
Because the feeling of a 90 degree bank in the dark can’t detect if it’s to the right or left
What’s vection and what kind of illusion is it ?
Induced motion
Falsely perceived motion
(sensory illusion)
What do you use the abbreviation ICCHAFFSS for ?
Sensory illusions within the aviation enviroment
What does ICCHAFFSS stand for ?
Induced motion
Confusion with ground lights
Crater illusion
Height persption illusion
Autokinesis
False horizon
Fasination/fixation
Structural illusion
Size distance illusion
What’s the “confusion with ground light” problem ?
Mistake groundlight for starts or starts for groundlight
What’s the problem with “Crater illusion”
Sensation that you are landing into a crater (caused by search light)
What the problem with “Height persption illusion”
DVE - pilot loses sight of ground
Pilot misjudge altitude
What the problem with “autokinesis” ?
Primary occurs at night and pilot can see things (stars) move if visually ficating on it for some seconds
( at night you can loose sight of aircrafts, lights, in the sky )
What’s the problem with “Size-distance-illusion” ?
If you are used to land at a wide runway and have to land at a narrow - you think that you are too high
What sensation can an upsloping runway give ?
What you are too high
you see more of the runway which gives you the sendation of being high
What illusion/understanding can fog/haze give to an object?
That it’s further away
What visual illusion can be caused by tall wavy grass ?
induced motion
What’s the 2 vestibular illusions and where in the ear does each happen?
Somatogyral (semicircular canals) & somatogravic (Otolith organs)
Which is the most common form of spacial disorientation ?
The Leans
Occurs when a pilot fails to perceive angular motion
You can find yourself in a bank withour knowing about it
What’s this most deadly illusion, and why?
Coriolis illusion (type 3 SD)
May occur during prolonged turns
How can you prevent coriolis illusion ?
Not moving head rapidly in a turn
Name the somatogravic illusions
G - Excess
Occurs when sustained G of > 1G
Change in magnitude
Pilot overbanks
Elevator
Up or downshit of aircraft
Pilot erroneously corrects
What are somatogravic illusions caused by ?
Caused when changes in gravity or linear acceleration and deceleration stimulate the otolith organ
How to prevent SD ?
Training
Fly either VMC & IMC
Trust instruments
Avoid DEATH factors
Aircrew coordination
Name the 3 dynamics of SD ?
Visual dominance
Vestibular suppresion
Vestibular opportunism
Which of the vistibular systems can cause Coriolis and the leans
The semicircular canals
Which vestibular illusion come from a stimulence in the semicircular canals ?
Somatogyral
Which vestibular illusion come from a stimulence of the otolith organs ?
Somatogravic
Which somatogravis illusions are there are what are they caused by ?
G-exess (can cause overbank - false pitch sensation)
Elevator (may pitch nose down because +Gz gives a climb sensation)
Caused by otolith organs
What type of SD would the coriolis illusion most likely cause ?
Type 3
Name the somatogyral illusions
The leans
Graveyard spin
Coriolis
Whats the most dangerous SD type?
Type 1 (unrecognized)
What is DVE
Degraded visual environment is a State of reduced visibility
What SD risk factors can be readily and continually assessed?
Task saturation
Meteorological conditions conducive to DVE
Decreasing flight visibility
Lack of visual cues
