What is the procedure if the automatic brakes do not hold on a grade?

When automatic brakes do not hold on a grade, making a brake pipe reduction prior to seeking assistance is vital. This action ensures that the train's brakes receive additional air pressure, providing a more robust braking force. By reducing the brake pipe pressure, the train can often regain enough braking capability to hold the train in place, especially on steep grades where the risk of rolling is higher.

This procedure is essential to prevent potential accidents caused by a runaway train. It allows the engineer to assess the effectiveness of the brakes under the current conditions and prepares the train for possible assistance if needed. Other methods, such as immediately implementing emergency procedures, may escalate the situation unnecessarily without first attempting to stabilize the train with a brake pipe reduction.

Using only the independent brake may not provide adequate stopping power for the entire train. Performing a dynamic brake test is not typically appropriate in a scenario where immediate action is required to prevent movement. Therefore, proceeding with a brake pipe reduction is the most logical first step in addressing the issue of brakes that do not hold.