Definition
A vestibular illusion caused by an abrupt vertical acceleration, such as that produced by an updraft, in which the pilot falsely senses that the aircraft is in a climb and reacts by pushing the nose down. An abrupt downdraft produces the opposite illusion, with the pilot sensing a descent and pulling the nose up.
Plain English
When the aircraft is suddenly pushed upward by rising air, your body feels like the nose has pitched up into a climb, even though it hasn't. The natural reaction is to lower the nose to 'correct' a climb that isn't really happening. A sudden drop from sinking air does the reverse.
Context Anchor
Seen in instrument flying when discussing inner-ear illusions that can happen in clouds, at night, or anytime the outside horizon is not reliable.
Derivation
Named after the elevator in a building. The sudden upward or downward push you feel when an elevator starts moving is the same kind of vertical acceleration the inner ear misreads in flight.
Why Pilots Care
Unrecognized elevator illusion can prompt the pilot to make incorrect pitch corrections, leading to spatial disorientation or loss of control.
Analogy
Similar to the stomach-dropping or lifting feeling when an elevator starts or stops moving.
Grounding Statement
If the aircraft is suddenly lifted upward and you cannot see a clear horizon, your body can mistake that lift for the nose pitching up.
Intuition Check
Do not read “elevator” here as the tail control surface. In “elevator illusion,” it means an elevator-like upward motion that tricks your sense of balance.
Example Sentence 1
Flying through a strong thermal in cloud, the pilot felt a sudden climb and almost pushed the nose down before recognising the elevator illusion and trusting the attitude indicator.
Example Sentence 2
As the aircraft accelerated in the level-off from a missed approach, the elevator illusion made the instruments appear to show a climb that was not occurring.