A commercial motor vehicle driver transporting a heavy load is approaching the summit of a steep mountain downgrade with a designated safety pull-off area. Place the following operational procedures in the correct chronological order that the driver must execute to safely prepare for and start the descent.
- 1Pull completely into the summit brake check pull-off area, secure the vehicle, and perform a physical inspection of brake adjustment, air pressure, and drum condition.
- 2Calculate the maximum safe descent speed based on total vehicle weight, grade steepness and length, road surface conditions, and weather.
- 3Shift the transmission into the appropriate low gear before crossing the crest and starting down the slope.
- 4Begin the descent, using engine compression braking as the primary speed retarder and applying snub braking only when speed reaches the safe maximum.
Answer
1. Pull into the summit brake check area and inspect the foundation brake system. 2. Calculate the maximum safe descent speed based on vehicle weight and downgrade conditions. 3. Shift the transmission into the proper low gear before cresting the hill. 4. Begin the descent relying primarily on engine compression braking supplemented by snub braking.
Safe mountain descent requires a structured, proactive sequence. The driver must first verify brake system integrity at the summit pull-off while stationary. Next, the driver calculates a safe speed based on total vehicle weight and road conditions. The driver then shifts into the correct low gear before cresting the hill to prevent gear lockouts or freewheeling. Finally, the driver commences the descent, utilizing engine retarding power as the primary control and applying short, firm snub braking cycles only when necessary.
Step-by-Step Solution
Key Concept
Pre-descent summit inspection, pre-crest low gear selection, and snub braking speed management during steep mountain downgrades.
Estimated Time:1m 15s