Which control surfaces affect roll in an aircraft?

The ailerons are the primary control surfaces that affect roll in an aircraft. They are located on the outer wings and operate by moving in opposite directions to each other. When one aileron is deflected upwards, the corresponding wing produces less lift, while the opposite wing, with its aileron deflected downwards, generates more lift. This differential in lift causes the aircraft to roll towards the wing with the aileron raised.

Understanding the specific roles of the other control surfaces helps clarify their function in flight dynamics. Elevators are responsible for controlling pitch, enabling the aircraft to ascend or descend. The rudder is used to control yaw, which helps in coordinating turns and stabilizing the aircraft's heading. Flaps primarily increase lift and drag, useful during takeoff and landing, but they do not directly influence the rolling motion of the aircraft.

Therefore, while other control surfaces play critical roles in flight, only the ailerons are designed specifically to control rolling motion.