← All explained questions · Supplemental · VII — Slow Flight, Stalls, and Spins
Stall warning systems in most light GA aircraft are designed to activate at approximately
Choices
10 knots above stall speed.
10 knots above is too early for most stall warning systems.
✓ 5-10 knots BEFORE the actual stall.correct
typically a horn or buzzer triggered by an AoA-actuated vane on the leading edge that lifts as airflow direction changes near critical AoA. Stall warning vanes activate 5-10 KIAS before stall to give the pilot time to react. They're AoA-driven, not airspeed-driven, so they fire correctly in turns and accelerated stalls. A stall warning during normal flight (not approaching stall) suggests vane damage, ice on the leading edge, or AoA system failure.
exactly at the stall.
Warning at the stall would be too late.
20 knots after the stall.
Warning AFTER stall defeats the purpose.
Why
typically a horn or buzzer triggered by an AoA-actuated vane on the leading edge that lifts as airflow direction changes near critical AoA. Stall warning vanes activate 5-10 KIAS before stall to give the pilot time to react. They're AoA-driven, not airspeed-driven, so they fire correctly in turns and accelerated stalls. A stall warning during normal flight (not approaching stall) suggests vane damage, ice on the leading edge, or AoA system failure.
FAA source: FAA-H-8083-25C, Ch. 7, Aircraft Systems - Stall warning systemsbrowse the reference library →
Original study question written for this course — representative of FAA knowledge-test topics, not an actual current FAA exam question.