Manual Cylinder Release

Having air in brake cylinders is not always desirable. For vehicles that sat unused for some time, the brake cylinder is likely empty due to leaks in the system . However, if a vehicle was used recently, its brake cylinder might still be pressurized and its brakes applied. When shunting , for example, it is quicker to be able to move cars around without having to wait for the brake pipe to pressurize to release the brakes.

For this reason, every vehicle with air brakes is fitted with a way to manually dump pressure from the brake cylinder. This is done by operating a red handle found on the outside of a vehicle. Pulling this handle will release the brakes immediately on cars that have it applied by air pressure.