What can cause brake fade in air brakes?

Answer: A — Excessive heat build-up due to prolonged braking

Brake fade in air brake systems is primarily caused by excessive heat build-up due to prolonged braking. When brakes are applied continuously or with intense force, the friction generated between the brake linings and the brake drums or rotors generates a significant amount of heat. If this heat is not dissipated quickly enough, it can lead to a decline in braking performance known as brake fade. During brake fade, the materials that make up the braking components can lose their effectiveness. For example, the friction material may become glazed due to overheating, reducing its ability to create the necessary friction needed to stop the vehicle. The air brake system, which relies on the expansion of compressed air to operate, can also experience issues if the components become too hot, affecting the air supply and pressure. While increased air flow through the compressor, excess lubrication, or insufficient brake fluid might be relevant in other contexts, they do not directly lead to brake fade. The critical factor that impacts the performance of air brakes in this case is the management of heat generated during braking.