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.
Plain English
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.
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 (air) and dynamis (force or power), so it relates to forces produced by air in motion. ‘Balance’ 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.
Why Pilots Care
Lower control forces reduce fatigue and improve precision, especially at higher speeds where hinge moments grow rapidly.
Analogy
It is like balancing a tray in your hands. If the weight is even, the tray stays level; if the weight shifts, you have to correct it to keep it steady.
Intuition Check
Balance does not mean the airplane is motionless. Here it means the air forces are matched well enough that they do not create an unwanted turning or tilting tendency.
Example Sentence 1
The designers added an aerodynamic balance to the rudder so pilots could maintain control with reasonable pedal force at high speeds.
Example Sentence 2
Horn-type aerodynamic balance on the rudder keeps pedal forces manageable during crosswind landings.