AFOQT Practice Test

Trim tabs are primarily used to help maintain an aircraft's desired flight attitude without continuous control input by the pilot. They are small adjustable surfaces located on the trailing edge of larger control surfaces like ailerons, rudders, or elevators. By adjusting these tabs, pilots can offset any rolling, pitching, or yawing moment that may arise due to asymmetric loading, center of gravity changes, or other factors that can lead to unwanted aircraft attitudes. This adjustment allows the pilot to relieve control pressure, making the aircraft easier to fly and more stable during various flight conditions.

The other options do not accurately describe the primary function of trim tabs. For instance, they do not increase thrust, which is related to engine performance rather than control surface adjustment. While they assist in the overall control of flight, they are not considered part of the primary flight control system itself. Also, trim tabs do not serve any purpose with respect to landing gear adjustments, which pertain to the aircraft's structural components rather than its aerodynamic control.