What is the 'at rest' position for the Ailerons when the aircraft is on the ground?

What is the 'at rest' position for the Ailerons when the aircraft is on the ground?

• A. Neutral
• B. Up
• C. Down
• D. Droop

Answer: (D)

On the A320, the aileron surfaces are held in position by hydraulic actuators when the system is powered. When the aircraft is on the ground and those hydraulics aren’t actively centering the surfaces, gravity makes the heavy control surfaces settle downward. That slight downward bias is called droop, so the natural at-rest condition on the ground is a down, or drooped, aileron. In flight, hydraulic pressure and the flight control laws hold the ailerons neutral, eliminating the droop.

On the A320, the aileron surfaces are held in position by hydraulic actuators when the system is powered. When the aircraft is on the ground and those hydraulics aren’t actively centering the surfaces, gravity makes the heavy control surfaces settle downward. That slight downward bias is called droop, so the natural at-rest condition on the ground is a down, or drooped, aileron. In flight, hydraulic pressure and the flight control laws hold the ailerons neutral, eliminating the droop.