Definition
A verbal callout made during the takeoff roll that requires a positive verbal response from the pilot at the controls, used to confirm that the flying pilot is alert, responsive, and capable of continuing the takeoff. A missing or abnormal response is treated as a sign of incapacitation and is grounds for rejecting the takeoff.
Plain English
A spoken check during takeoff where one pilot says something that the other pilot must answer clearly. If the answer doesn't come, or sounds wrong, it's a signal to stop the takeoff because the flying pilot may be unwell or unresponsive.
Context Anchor
Used in multi-pilot takeoff briefings and rejected takeoff planning, especially during the takeoff roll when there is little time to decide who is controlling the airplane.
Derivation
Incapacitation comes from the Latin 'in-' (not) and 'capax' (able). It means being unable to function. The check is named for what it's looking for: a pilot who has suddenly become unable to fly the airplane.
Why Pilots Care
Ensures immediate transfer of control during a critical phase if the pilot can no longer act.
Grounding Statement
If the pilot flying does not respond to the agreed callout during the takeoff roll, the other pilot has a preplanned reason to act immediately.
Intuition Check
Do not assume incapacitation only means the pilot is unconscious. It can mean any sudden condition that keeps the pilot from safely responding or flying the airplane.
Example Sentence 1
During the takeoff roll, the pilot monitoring called 'airspeed alive' as the pilot incapacitation check, and the pilot flying responded 'checked' to confirm alertness.
Example Sentence 2
With no answer to the pilot incapacitation check, the safety pilot took the controls and completed the stop.