Plain English Meaning

It is a way of building a control surface so the wind helps move it, instead of the pilot having to fight the wind alone. The result is lighter, easier control inputs, especially at higher speeds.

Full Definition

A design feature on a flight control surface that uses the airflow itself to reduce the force a pilot must apply to move the control. It is achieved by shaping or positioning the control surface so that part of it sits ahead of its hinge line, allowing the airflow to assist the pilot's input rather than resist it.

Context Anchor

Seen when studying pressure distribution over a wing and how changes in airflow can affect aircraft stability and control.

Derivation

‘Aerodynamic’ comes from Greek aer () and dynamis (force or ), so it relates to forces produced by air in motion. ‘’ here means offsetting one force with another. Together the term describes using airflow forces to offset the force the pilot would otherwise need to apply.