What it does
Ailerons control roll — the rotation of the aircraft around the axis running nose to tail. They come in a pair, one per wing, and work in opposition: when one deflects up, the other deflects down.
Deflecting an aileron changes the camber of that section of the wing, which changes how much lift it produces. The wing with the lowered aileron makes more lift and rises; the wing with the raised aileron makes less and drops. The aircraft rolls toward the dropping wing.
Quick reference
| Controls | Roll (longitudinal axis) |
| Location | Trailing edge, outboard section of each wing |
| Moves in | Opposition (differential pair) |
| Pilot input | Lateral stick / yoke movement |
Diagram
Adverse yaw: the rising wing's down-deflected aileron also adds drag, pulling the nose away from the turn. Pilots counter this with rudder, and designers reduce it with differential or Frise ailerons.
Related terms
- Elevator — controls pitch (coming soon)
- Rudder — controls yaw (coming soon)
- Flaps — increase lift and drag for landing (coming soon)