Definition
The replaceable friction material attached to the brake shoes, pucks, or pads of an aircraft wheel brake assembly. When the brake is applied, the lining is pressed against a rotating disc or drum, and the friction between the two slows the wheel.
Plain English
The wear surface inside the brake that rubs against the spinning part of the wheel to slow the aircraft down. It is designed to wear out gradually so it can be replaced without damaging the rest of the brake.
Context Anchor
Seen during aircraft maintenance, preflight inspection discussions, and brake wear checks.
Derivation
Lining comes from the idea of a layer attached to the inside of something — like the lining of a coat. In a brake, it is the sacrificial layer bonded or riveted to the metal shoe or pad that takes the wear so the structural parts do not.
Why Pilots Care
Worn or glazed linings reduce braking effectiveness, increase landing roll distance, and can cause brake fade or failure.
Intuition Check
Do not think of brake lining as a hose or fluid line. Here, lining means the solid friction material that wears down as the brakes are used.
Example Sentence 1
During preflight, the pilot checked the brake wear indicator pins to confirm the brake linings still had enough material remaining.
Example Sentence 2
After a hard landing the pilot inspected the brake linings for glazing or uneven wear.