What is the primary function of the ailerons on an aircraft?

The primary function of the ailerons on an aircraft is to control roll. Ailerons are located on the outer wings of an airplane and work in opposition to each other. When the pilot moves the control yoke or stick to the right, the right aileron deflects upward while the left aileron deflects downward. This movement creates differential lift: the upward-deflected aileron reduces lift on that wing, while the downward-deflected aileron increases lift on the opposite wing, causing the aircraft to roll towards the right. Conversely, the same principle applies when the control is moved to the left.

This roll control is essential for maneuvering the aircraft during flight, allowing the pilot to bank the aircraft during turns, maintain level flight attitude, and achieve coordinated flight. Understanding how ailerons function is critical for effective aircraft control and safe flying practices. Other options pertain to different flight control surfaces or aspects of flight; for instance, pitch is primarily controlled by the elevators, yaw by the rudder, and climb rate management involves other factors such as throttle and elevator adjustment.