FAA Instrument Rating Airplane (IRA)Aeromedical and ADMEasy
A pilot flying at night over a sparsely lit rural area maintains what appears to be a level attitude by referencing a sloping line of ground lights that the pilot mistakes for the horizon. The airplane is actually descending into terrain. This scenario best illustrates which type of illusion?
- AElevator illusion
- BFalse horizon
- CAutokinesis
- DBlack hole approach illusion
Show answer & explanationAnswer & explanation
Correct answer: B. False horizon
A false horizon illusion occurs when a pilot confuses a sloping cloud deck, ground lights, or a dark horizon with the actual horizon, leading to a dangerously incorrect attitude reference. This is distinct from the black hole illusion, which specifically involves misjudging approach angle due to limited visual cues over dark terrain during landing.
Why the other options are wrong
- A. Not a recognized FAA spatial disorientation term.
- C. Autokinesis is a stationary light appearing to move, not misreading a horizon reference.
- D. Black hole illusion specifically applies to final approach with an unlit runway environment.
False Horizon Illusion
An illusion where a pilot misinterprets sloping cloud formations, ground lights, or a featureless dark sky as the true horizon, leading to incorrect aircraft attitude control.
- Common at night or in reduced visibility
- Ground lights or sloping clouds can be mistaken for level horizon
- Correct by relying on flight instruments, not outside visual references
Memory trick: Lights lie at night — trust your dials, not the skyline.