Definition
A cockpit instrument that displays the wing's current angle of attack — the angle between the wing's chord line and the oncoming airflow — relative to the angle at which the wing will stall. It typically shows the pilot how much usable lift margin remains before the critical (stalling) angle of attack is reached, often using a color-coded scale, lighted segments, or a moving needle.
Plain English
A gauge in the cockpit that shows how close the wing is to stalling. It tells the pilot whether they have plenty of lift in reserve or whether they are getting near the point where the wing will stop flying.
Context Anchor
Seen in airplanes equipped with angle of attack systems, especially during approach, landing, slow flight, turns, and other situations where stall awareness matters.
Derivation
‘Angle of attack’ describes the angle at which the wing meets the air. ‘Indicator’ comes from Latin indicare, meaning ‘to point out.’ So the instrument literally points out the angle at which the wing is meeting the air.
Why Pilots Care
Gives direct, immediate stall-margin information that remains valid regardless of weight, bank, or airspeed changes.
Analogy
An AOA indicator is like a margin gauge for the wing. It does not just tell you how fast you are moving; it shows how much room the wing has before it reaches a poor flying condition.
Grounding Statement
If the nose is raised too much for the wing’s current flight path, the AOA indicator moves toward the warning range.
Intuition Check
Do not treat an AOA indicator as just another airspeed indicator. Airspeed tells how fast the airplane is moving; the AOA indicator shows how the wing is meeting the air.
Example Sentence 1
On final approach, the pilot cross-checked the AOA indicator to confirm the wing had a safe margin above stall.
Example Sentence 2
In the stall maneuver the AOA indicator reached the red zone at the same moment the wing stalled.