Integration of Senses and Illusions

Question 0

Name and explain three illusions associated with vision.

Answer 0

1) Oculargravic- when aircraft accelerates make give vision sensation of going backwards.
2) Autokinesis- due to eye movements and lack of reference- staring at an object during night flight may cause it to move around.
3) False horizon- without a clearly defined horizon, a person will line themselves up with the closest thing to it

Question 1

Name and explain the illusions that are associated with the vestibular system.

Answer 1

1) Somatogyral- illusions of turning; the leans; straight and level with no acceleration, fluid in semi-circulars are not moving -when you’re in a steady state turn coming out of the turn you’ll get a false sensation of turning the wrong way sending you into graveyard spin
2) Coriolis- after being in a stabilized constant rate turn will cause new equilibrium so when moving head it will cause illusion of tumbling
3) Vertigo- a severe version of Coriolis where you feel as though you’re spinning out of control
4) Sematogravic- because of otoliths searching for gravity- if you increase one 1G it cause a feeling of 45* pitch up. Positive G’s give illusion of climbing, negative G’s give illusion of diving

Question 2

Name and explain two illusions dealing with the runway.

Answer 2

1) Runway width illusion.
- narrow runway can cause one to think they are higher than they actually are, leading to a lower approach
- wider runway can cause one to think they are lower than they actually are, leading to a higher approach
2) Runway slope illusion
- a down-sloping runway can cause illusion of higher flight,
leading to lower approach
- an up-sloping runway can cause illusion of lower flight,
leading to higher approach

Question 3

Explain illusions caused by absent or different focal cues.

Answer 3

Similar but slightly different terrain around an airport may cause you to come in at a different angle.
Landing strip covered by water or snow will present problem of not having a matching picture

Question 4

Explain black hole approaches.

Answer 4

When there is no lighted terrain (worse when only runway lights are seen), without peripheral cues the pilot will feel as if the aircraft is stable, each movement will make the pilot feel as though the runway is moving, makes it difficult to judge distance to ground causing undershooting