Examkin

Question

Difficulty: EasySpeed on Curves and Downgrades

Advisory speed limit signs on highway exit ramps and sharp curves are generally established for passenger vehicles. What is the safest speed management practice for a commercial driver when approaching one of these curves?

  1. A
    Enter the curve at the posted advisory speed and brake firmly once the vehicle reaches the apex of the turn.
  2. Reduce vehicle speed to below the posted advisory speed before entering the curve.Answer
  3. C
    Maintain continuous light foot pressure on the service brakes throughout the entire curve to hold momentum.
  4. D
    Activate full auxiliary engine retarder braking while turning to counteract centrifugal force.

Answer

Reduce vehicle speed to below the posted advisory speed before entering the curve.
Because commercial vehicles carry high centers of gravity and heavy loads, posted advisory speeds designed for cars are often too fast for them. Safe driving protocol requires reducing vehicle speed to below the posted advisory speed before entering the turn, ensuring maximum tire traction and stability.

Step-by-Step Solution

1
Recognize the vehicle dynamics and sign limitations
Identify that posted curve advisory speeds are calibrated for cars with low centers of gravity, not heavy commercial vehicles.
Commercial vehicles can easily roll over or skid out if taking a curve at passenger car speeds.
2
Determine the proper timing and magnitude of speed adjustment
Slow the vehicle to a safe speed—typically below the advisory limit—prior to initiating the turn.
Slowing down beforehand allows the driver to maintain gentle acceleration through the curve, stabilizing the vehicle.

Key Concept

Safe Speed Selection and Entry Timing on Curves
Estimated Time:45s
Rate this question

Topics

Speed on Curves and Downgrades

More questions from this topic