How it Works: Disc Brakes

Despite using them so little, it seems like pilots like to talk a lot about brakes. Usually it’s how to avoid using them. Unlike a car where brakes are used dozens of times on a typical drive, in airplanes we use brakes for taxiing and sometimes for landing.
A disc brake system consists of a rotor or fixed disc that makes up part of the wheel, a caliper that’s usually activated hydraulically with brake fluid, and a pad that pushes against the rotor. When we step on the brake or grab the handle, the caliper pushes out pistons that press the pad tight to the rotor.
The key to operating aircraft brakes is to ensure you don’t overdo it. They can hold the airplane tight during the run-up, when making tight turns, and a short-field takeoff, but for most landings it is better to let the airplane slow down by itself. If you step on the brakes during the takeoff or landing it could damage the airplane, cause a fire, or send you careening off the runway. Easy does it.