brake failure

Brake fade (or vehicle braking system fade) is the reduction in stopping power that can occur after repeated or sustained application of the brakes of a vehicle, especially in high load or high speed conditions. Brake fade can be a factor in any vehicle that uses a friction braking system including automobiles, trucks, motorcycles, airplanes, and bicycles.
Brake fade is caused by a buildup of heat in the braking surfaces and the subsequent changes and reactions in the brake system components and can be experienced with both drum brakes and disc brakes. Loss of stopping power, or fade, can be caused by friction fade, mechanical fade, or fluid fade. Brake fade can be significantly reduced by appropriate equipment and materials design and selection, as well as good cooling.
Brake fade occurs most often during high performance driving or when going down a long, steep hill. It is more prevalent in drum brakes due to their configuration. Disc brakes are much more resistant to brake fade because the heat can be vented away from the rotor and pads more easily, and have come to be a standard feature in front brakes for most vehicles.

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