Definition
A small, hinged metal tab mounted on the leading edge of a wing that pivots upward as the angle of attack increases. When the airflow approaches the stalling angle, the vane is deflected enough to close an electrical circuit, activating a horn or light in the cockpit to warn the pilot of an impending stall.
Plain English
A little movable flap on the front edge of the wing that gets pushed up when the wing is getting close to losing lift. When it moves far enough, it triggers a warning sound or light in the cockpit so the pilot knows a stall is coming.
Context Anchor
Seen during aircraft inspections, in stall warning system descriptions, and when checking that the stall warning works before flight.
Derivation
‘Vane’ comes from the Old English ‘fana,’ meaning a small flag or blade that moves with the wind. Like a weather vane, this device moves in response to airflow — here, signalling when the wing is reaching its stall point.
Why Pilots Care
It gives an early, reliable warning of an impending stall so the pilot can lower the nose before lift is lost.
Intuition Check
Do not read “stall” here as the engine stopping. This warning is about the wing getting too close to losing smooth airflow and lift.
Example Sentence 1
During preflight, the pilot gently lifted the stall warning vane and listened for the warning horn in the cockpit to confirm the system was working.
Example Sentence 2
During preflight the pilot moved the stall warning vane by hand to confirm it activated the warning system.