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Difficulty: Very hardEvasive Steering and Avoiding Collisions

A commercial operator is driving a 50-foot combination vehicle at 60 mph on a dry interstate, maintaining a 5-second following distance behind a passenger vehicle. The passenger vehicle suddenly collides with an immovable, unlit obstacle and stops instantaneously. Realizing that a collision is imminent if they maintain their current path, the truck driver must take immediate action. According to commercial driving safety standards, which evasive maneuver and accompanying rationale is correct?

  1. A
    Simultaneously apply heavy brake pressure and sharply rotate the steering wheel at least 15 degrees to overcome the vehicle's normal allowable steering play, ensuring an abrupt lane change.
  2. B
    Maintain the current lane and apply full brake pressure immediately, as the mechanical braking distance at 60 mph is shorter than the physical space provided by the 5-second gap.
  3. Keep hands firmly on the steering wheel, execute a rapid steering maneuver to clear the hazard without applying the brakes, and immediately counter-steer to restabilize the vehicle.Answer
  4. D
    Apply maximum threshold braking without altering the vehicle's path, as a 5-second gap for a 50-foot vehicle satisfies the commercial following distance formula regardless of the travel speed.

Answer

Keep hands firmly on the steering wheel, execute a rapid steering maneuver to clear the hazard without applying the brakes, and immediately counter-steer to restabilize the vehicle.
When a hazard appears suddenly at highway speeds and the stopping distance is inadequate, evasive steering is the only viable option. The CDL manual explicitly states that a driver must not apply the brakes while making a sharp turn to avoid locking the wheels and causing a skid. Once the steering maneuver clears the obstacle, the driver must immediately counter-steer to pull the vehicle back into a stable, straight path.

Step-by-Step Solution

1
Analyze the available space and stopping distance requirements.
Determine that a 5-second gap at 60 mph is insufficient space to stop a 50-foot commercial vehicle.
The following distance formula requires 1 second per 10 feet of length (5 seconds) PLUS 1 additional second for speeds over 40 mph (total 6 seconds required). Total stopping distance (perception + reaction + brake lag + braking) far exceeds the available space.
2
Select the appropriate emergency avoidance maneuver.
Choose evasive steering instead of emergency braking.
At highway speeds, a commercial vehicle can be steered around an obstacle in a shorter distance than it takes to stop.
3
Execute the steering maneuver correctly.
Steer quickly to an open path without touching the brake pedal.
Applying the brakes during a sharp turn drastically increases the risk of wheel lockup, resulting in a loss of steering control, skidding, or a potential rollover.
4
Stabilize the vehicle post-maneuver.
Immediately counter-steer the moment the hazard is cleared.
Counter-steering (turning the wheel back in the opposite direction) is necessary to realign the vehicle and prevent it from careening off the road or into another lane.

Key Concept

Evasive Steering Execution and Stopping Distance Dynamics
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Topics

Evasive Steering and Avoiding Collisions

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