If more than 18-psi brake pipe reduction is needed to control train speed on a grade on balance braking, what is the recommended action?

If more than 18-psi brake pipe reduction is needed to control train speed on a grade on balance braking, what is the recommended action?

• A. Decrease throttle and coast.
• B. Notify dispatcher and continue with caution.
• C. Stop the train using an emergency application.
• D. Apply maximum dynamic braking.

Answer: (C)

Balancing braking on a grade relies on using both dynamic braking and the air brake together to control speed. If you find you must drop the brake pipe pressure by more than about 18 psi just to keep the train under control, that indicates the combination of brakes isn’t providing a safe, controllable retardation for the grade. In such a situation the safest course is to bring the train to a stop using an emergency brake application. The emergency brake delivers the maximum braking effort available across the train, allowing you to quickly stop and reassess before attempting to proceed under safer conditions. Decreasing throttle and coasting wouldn’t address the insufficient braking force, notifying the dispatcher without taking action doesn’t reduce the risk, and relyingだけ on dynamic braking isn’t enough here since the scenario centers on the need for substantial air-brake action to manage speed on the grade.

Balancing braking on a grade relies on using both dynamic braking and the air brake together to control speed. If you find you must drop the brake pipe pressure by more than about 18 psi just to keep the train under control, that indicates the combination of brakes isn’t providing a safe, controllable retardation for the grade. In such a situation the safest course is to bring the train to a stop using an emergency brake application. The emergency brake delivers the maximum braking effort available across the train, allowing you to quickly stop and reassess before attempting to proceed under safer conditions.

Decreasing throttle and coasting wouldn’t address the insufficient braking force, notifying the dispatcher without taking action doesn’t reduce the risk, and relyingだけ on dynamic braking isn’t enough here since the scenario centers on the need for substantial air-brake action to manage speed on the grade.