Wheels and brakes

In the same way as propulsion or lift, braking is one of the vital functions on an aircraft. Thanks to the braking function the aircraft is able to come to a halt after landing, taxies in safety and can stop in an emergency if there is an aborted take off.

Whether on a bicycle, car or aircraft, the problem is the same: the kinetic energy of the moving vehicle has to be absorbed and then transformed into heat in order to dissipate it. To do this a solid object in the structure of the vehicle, the brake, rubs on the turning wheel or on an object attached to the wheel. However a difference of size between the different moving objects affects the amount of energy to be absorbed as it is proportional to the mass and speed squared (the famous ½ mv²) of moving objects.

Stopping an Airbus A340 or a Boeing 777 travelling at 300 km/h in a few hundred metres means absorbing more than 1 billion joules in a few tens of seconds - around 125 mega joules per wheel and brake! Although the risk is in the order of 1 in 1 million take offs, it is the most extreme case that Messier-Bugatti-Dowty’s wheels and brakes have to deal with in the unlikely event of an aborted take off.

Service cards

737 Next-Generation
carbon brake

787 electric
carbon brake

A350 XWB
carbon brake