At locations where an Inbound Mechanical Inspection will be made, how much brake pipe reduction should be made before locomotives are detached?

At locations where an Inbound Mechanical Inspection will be made, how much brake pipe reduction should be made before locomotives are detached?

• A. 60-psi
• B. 70-psi
• C. 80-psi
• D. 90-psi

Answer: (B)

The main idea is to use brake pipe pressure control to secure the train during locomotives detachment. Reducing the brake pipe pressure causes the automatic brakes on the train to apply. For an inbound mechanical inspection, you want a moderate brake application that holds the train in place when the locomotives are being detached, without overdoing the braking or causing unnecessary wear. This level is chosen because it provides a reliable hold under typical yard conditions, reducing the risk of the train moving during the uncoupling process. If the reduction is too small, the train might move; if it’s too large, you could cause excessive braking or wheel slide.

The main idea is to use brake pipe pressure control to secure the train during locomotives detachment. Reducing the brake pipe pressure causes the automatic brakes on the train to apply. For an inbound mechanical inspection, you want a moderate brake application that holds the train in place when the locomotives are being detached, without overdoing the braking or causing unnecessary wear. This level is chosen because it provides a reliable hold under typical yard conditions, reducing the risk of the train moving during the uncoupling process. If the reduction is too small, the train might move; if it’s too large, you could cause excessive braking or wheel slide.