Angle of attack indicator
A cockpit AoA indicator measures angle of attack, shows margin to critical (stalling) AoA. PHAK term: stall margin awareness (PHAK ch.5).
- Without one, AoA is "invisible". Airspeed not a reliable stall cue: airplane can stall at any speed.
- Stall speed moves with loading, bank, CG (see stall-speed and factors-affecting-stall-speed). AoA reads margin directly (PHAK ch.5).
- Measures several parameters, computes current AoA, shows proximity to critical AoA.
- Limits on effectiveness (PHAK ch.5): calibration techniques, unheated probes or vanes, indicator type, flap setting, wing contamination.
- Most light aircraft lack one (TP 1102).
Trap: Reads angle of attack, not airspeed; does not track the ASI.
References
- FAA-H-8083-25 PHAK ch.5 Aerodynamics of Flight, Angle of Attack Indicators
- TP 1102 Aeroplane Flight Training Manual