FAA Commercial Pilot Airplane (CAX)Human Factors and ADMMedium
While flying straight and level at night over sparsely lit terrain, a pilot stares at a single ground light for an extended period. The pilot begins to perceive the light moving erratically even though the airplane is not maneuvering. This illusion is known as:
- AThe leans
- BSomatogravic illusion
- CAutokinesis
- DThe graveyard spiral
Show answer & explanationAnswer & explanation
Correct answer: C. Autokinesis
Autokinesis occurs when a stationary light is stared at in the dark for several seconds, causing it to appear to move due to small involuntary eye movements.
Why the other options are wrong
- A. The leans is a false sensation of banking, not related to a stationary light appearing to move.
- B. Somatogravic illusion involves acceleration being perceived as pitch-up, unrelated to fixed lights.
- D. The graveyard spiral involves a spatial disorientation during a prolonged turn, not a stationary light.
Autokinesis
A visual illusion in which a stationary light stared at in darkness appears to move.
- Caused by staring at a fixed point of light for several seconds in the dark
- Can be mistaken for another aircraft's movement
- Prevented by shifting the eyes/scanning rather than staring
Memory trick: Stare at a star, it starts to move — Autokinesis