Plain English Meaning

These are the extra controls on an aircraft that help the pilot fly more efficiently. They don't steer the airplane like the main controls do — instead, they fine-tune how the wings produce lift, slow the airplane down, or relieve the pilot from holding pressure on the main controls.

Full Definition

Flight controls that supplement the primary flight controls (ailerons, elevator, and rudder) to improve aircraft performance, reduce pilot workload, or modify the wing's lift and drag characteristics. Common secondary flight controls include flaps, slats, , , and .