Why must air brakes be cut out during certain inspections?

The necessity for cutting out air brakes during certain inspections primarily stems from the fact that the brakes may not release properly. This situation can occur due to various mechanical issues or malfunctions within the braking system. If the air brake system is not functioning as intended and is left engaged during an inspection, it can prevent accurate assessments of other components and may pose safety risks.

By cutting out the air brakes, inspectors can ensure that the train does not inadvertently become immobilized or pose a hazard while other safety checks are performed. This procedure is crucial for verifying the interworking of other systems, facilitating repairs, or performing maintenance without the brakes applying pressure or interfering. Such precautions are vital for maintaining operational safety and efficiency, ensuring that all aspects of the train’s equipment can be inspected and tested without the complications that active brakes might introduce.