Ground adjustable trim tabs are located on which control surface?

• A. Aileron
• B. Elevator
• C. Rudder
• D. None of the above

Answer: (A)

Trim tabs are small surfaces attached to a primary control surface that create a tiny aerodynamic force, helping the pilot hold a desired position with less effort. Ground adjustable trim tabs are those that are set on the ground to establish a pre-set trim condition.

In many light aircraft, this ground adjustment is done on the aileron. Placing the tab on the aileron allows you to bias the roll tendency without changing the elevator (pitch) or rudder (yaw) behavior, and it can be set before flight or during maintenance to compensate for typical loading and balance. That’s why the aileron is the best answer here.

Elevator or rudder trim tabs are common as cockpit-adjustable (in-flight) trim devices, but the phrasing “ground adjustable” points to the aileron in this context.