Aileron
An aileron is a primary flight-control surface that moves differentially to control roll about the aircraft’s longitudinal axis.
- Where it is
- On the outboard trailing edge of each wing in the generic transport-aircraft model.
- What it does
- Opposite aileron deflections change the lift distribution between the wings and create a rolling moment.
- Relationship
- Ailerons work with the roll-control system and may be assisted by spoilers on larger aircraft.
- Common confusion
- An aileron is not a spoiler. An aileron rotates at the trailing edge, while a spoiler rises into the airflow and reduces lift.
Check yourself
Without looking back, can you explain where the aileron is, what it does, and which component drives it or is driven by it?
Scope: Generic transport-aircraft teaching model. Reviewed 2026-09-09.