When decreasing speed on an ascending grade, what method preserves slack-stretched condition?

When decreasing speed on an ascending grade, what method preserves slack-stretched condition?

• A. Allow the grade to slow the train, reducing throttle one notch at a time to maintain a slack-stretched condition
• B. Use the emergency brake
• C. Increase throttle to hold speed
• D. Coast to stop

Answer: (A)

When you’re slowing on an ascending grade, you want the train to stay in tension between the locomotive and the cars rather than letting the slack take up or go slack. Gravity is helping you slow down, so the best method is to ease off the throttle in small steps. This lets the train decelerate gradually while the locomotive continues to pull, preserving the slack-stretched condition and avoiding a rush of slack that can cause jerks or shock loads. Using an emergency brake would cause a sudden deceleration with abrupt slack action, increasing shocks. Increasing throttle would not slow you, and coasting too long can reduce control of slack and speed.

When you’re slowing on an ascending grade, you want the train to stay in tension between the locomotive and the cars rather than letting the slack take up or go slack. Gravity is helping you slow down, so the best method is to ease off the throttle in small steps. This lets the train decelerate gradually while the locomotive continues to pull, preserving the slack-stretched condition and avoiding a rush of slack that can cause jerks or shock loads. Using an emergency brake would cause a sudden deceleration with abrupt slack action, increasing shocks. Increasing throttle would not slow you, and coasting too long can reduce control of slack and speed.