If a flap protection system with a hydraulic flap circuit is active and the aircraft is well above flap extension speed, what happens when the flap lever is moved to the down position?

• A. Flaps extend normally
• B. Flaps move normally but slower
• C. Flaps do not move because hydraulically locked
• D. Flaps unlock and retract

Answer: (C)

Flap protection that’s active will prevent flap movement if the aircraft is flying above the flap extension speed. In this situation, moving the flap lever to the down position doesn’t cause the flaps to move because the hydraulic valves lock the circuit and block hydraulic flow to the actuators. The system is safeguarding against deploying flaps at speeds where they could cause damage, so the flaps remain in their current position.