Air brakes are used to stop many different vehicles. Trains, trucks, trailers, and even airplanes all use different kinds of air braking systems. It is important to know what kinds of braking systems are available for maintenance and replacement. Knowledge of air brakes will help in many different mechanical situations.


The function of air brakes is to allow a large vehicle to stop more quickly that it would be able to with other braking systems. The traditional form of brakes is when a pad is applied to a spinning disc to slowly stop the movement of a vehicle. The problem with this kind of break is that there is sometimes not enough pressure to stop the vehicle in a timely manner. Too much heat is also generated from this braking system. Air brakes add additional stopping force to the braking system enabling vehicles to stop faster. Most larger vehicles use this braking system.


Air brakes work better on larger vehicles because they do not generate as much heat. Air pressure provides less friction against the discs or drums used to stop large vehicles which prevents the parts from overheating. There are many components in a vehicle air brake system. These systems consist of: an air compressor, brake linings or drums, exhaust and intake pipes, an air tank, brake chambers, numerous valves to contain and direct the flow of air and brake chambers which hold all of the other components together.


There are two main types of air brakes. The first kind is commonly used for trucks and trains. This kind of brake works along side a disc or drum breaking system but does not use friction to stop the vehicle, nor does it use fluid. Instead air pressure is applied to the brake which causes it to stop with much less heat generated. The other kind of air brake system uses electronic power to create the air pressure that slows vehicles down. These two types of system are the most commonly used air brake systems.

Disc brakes

Air brake systems used in conjunction with disc brakes are the most common type of air brake system. This system applies air pressure to the disc which is attached to the axel of the vehicle. The air pressure causes enough friction between the disc and the axel with gradually slows the vehicle down. However, this kind of air brake has one of the greatest stopping distances of any other braking system. It takes a large truck up to three or four times longer to come to a complete stop than a regular sized car.

Electronic systems

Another air brake system that has been developed is controlled by an electrical system. Wires are directly connected to each brake which creates a more precise stopping ability. The electronic systems are able to stop trucks much faster than previous braking systems. The electronic braking systems are better able to apply the perfect amount of air pressure to the brake to create a safer and more effective stop. The electronic systems are also used for other tasks such as distance logging and reporting problems with the brake systems.