Aeromed - Spatial Disorientation Flashcards
One acronym to remember the # visual illusions is ___.
13, FFF CRASH CSAR
The three systems that help maintain balance and equilibrium are:
Vision
Vestibular (Inner ear)
Proprioreceptive (Sense of touch)
What is spatial disorientation?
The inability to determine your position, attitude, or motion in relation to the surface of the earth or significant objects
What are the three kinds of spatial disorientation?
Type I - Unrecognized
Type II - Recognized
Type III - Incapacitating
Which is the most dangerous kind of spatial disorientation?
Unrecognized
Describe unrecognized spatial disorientation.
Pilot does not perceive any disorientation instruments and aircraft are performing normally. A hard landing due to height/depth misperception would be one example.
Describe recognized spatial disorientation.
Pilot perceives a problem, but might now know it is SD, may attribute to a control or instrument malfunction. Flying the aircraft at a roll due to false horizon would be one example.
Describe incapacitating spatial disorientation.
Pilot experiences overwhelming sensations and is unable to orient themselves either by visual or instrument cues.
The most important system for maintaining spatial orientation is ___.
Vision, contributes up to 80%.
The vestibular system of the inner ear is made up of what structures?
Otolith organs and semicircular canals
The otolith organs of the vestibular system respond to what sensations?
Acceleration (and deceleration) and gravity
The semicircular canals of the vestibular system respond to what sensations?
Roll, pitch, and yaw
Explain false horizon.
Pilot confuses cloud formations with the horizon or the ground and flys at a bank. Also occurs if pilot was inside for a prolonged period.
Explain fascination/fixation.
Focusing on the target/goal/problem and forgetting to maintain aircraft control or proper scan.
Two types: task or target fixation
Explain flicker vertigo
Caused by light flickering through rotor disk, or anti-collision lights on ground or in clouds. Usually only annoying or a distraction, may possibly cause seizures in some individuals.
Explain confusing ground lights
Confusing stars with ground lights, or vice versa. May occur along coastline or in rural areas.
Explain relative motion
The motion of another object causes the perception of self motion - another helicopter moving makes you feel as if you are moving the opposite direction.
Explain altered plane of reference
Inaccurate sense of altitude, attitude, or elevation due to a large object (mountain) that replaces the horizon. Or, the changing slope of a hill/valley may - aircraft not be able to climb faster than the change in elevation.
Explain structural illusion
Objects become distorted when looking at them through rain/fog/sleet, multiple panes of class, curved windows, etc
Explain height/depth illusion
Due to a lack of visual cues, crew perceives the aircraft to be higher than it actually is
Explain crater illusion
Crew perceives landing into a crater when the search light is positioned too far under the aircraft. Occurs particularly in tall grass
Explain size-distance illusion
False sense of distance or altitude when a crew member perceives an unknown object to be of a similar size to
Explain autokinesis
False sense of an object (light) moving when it is stared at for several seconds
Explain reversible perspective
False sense of direction when an object (aircraft) is moving towards/away from you
What are two ways to manage spatial disorientation
Refer to (and trust) your instruments
Transfer the controls
