Definition
Aerodynamic surfaces, typically deployed from the wings, that increase drag to control airspeed and rate of descent during a dive. Most commonly found on gliders, where they allow the pilot to descend steeply without exceeding speed limits and to control the approach path on landing.
Plain English
Panels that pop out of the wings to slow the aircraft down and let it come down more steeply without going too fast.
Context Anchor
Seen in aircraft operating handbooks, cockpit control labels, and training for gliders or other aircraft that use drag-producing panels for descent control.
Derivation
From 'dive' (a steep descent) and 'brake' (a device to slow motion). The name describes exactly what the surface does -- it brakes the aircraft during a dive.
Why Pilots Care
Allows precise control of descent speed to avoid exceeding structural limits or losing control in a steep dive.
Intuition Check
Dive brakes are not wheel brakes, and they do not stop the aircraft on the ground. They work in the air by adding resistance to the airflow.
Example Sentence 1
On final approach, the glider pilot extended the dive brakes to steepen the descent and touch down at the intended spot.
Example Sentence 2
During a rapid altitude loss, the pilot used dive brakes to prevent the airspeed from exceeding the red line.