What type of movement do ailerons primarily control in an airplane?

Ailerons primarily control movement along the lateral axis, which is also referred to as roll. When a pilot moves the control yoke or stick to the left or right, the ailerons on the wings respond by deflecting in opposite directions: one aileron goes up while the other goes down. This differential movement creates an unequal lift across the wings, causing the airplane to roll to the left or right.

Understanding this mechanism is essential for pilots, as controlling roll is critical for maneuvering the aircraft, maintaining level flight, and executing turns. This is distinct from pitch movement, which is controlled by elevators, and yaw movement, which is controlled by the rudder. Thus, the role of ailerons in controlling the roll is vital for overall flight dynamics and stability.