A commercial truck is traveling at a posted speed of on a rural expressway when a heavy downpour causes water to accumulate on the road surface. According to commercial driving safety standards for wet pavement, which action should the driver take to maintain vehicle control and prevent traction loss?
- AMaintain the current speed of but increase following distance, relying on the vehicle's air brake system to handle any sudden stops.
- Reduce speed by approximately one-third to about and turn off the engine retarder.Answer
- CSlow down to while setting the engine brake or retarder to maximum power to assist in continuous slowing.
- DMaintain highway speed until encountering standing water or a sharp bend, then apply the service brakes firmly to decelerate.
Answer
Reduce speed by approximately one-third to about and turn off the engine retarder.
On wet pavement, traction is significantly reduced, requiring commercial drivers to slow down by about one-third of their dry-road speed (e.g., from to about ). Furthermore, engine retarders must always be switched off whenever roads are wet, icy, or snow-covered because retarder braking force can easily lock the drive wheels and provoke a jackknife.
Step-by-Step Solution
Key Concept
Speed reduction and auxiliary braking safety on wet road surfaces
Estimated Time:1m 0s