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Difficulty: Very hardSkid Control and Recovery

When descending a rain-slicked gradient, if the trailer tires lock and the trailer begins to swing laterally out of its lane, the operator must execute a rapid counter-steer maneuver to physically pull the articulated combination back into alignment.

Answer: Answer

Answer

False
When trailer tires lock and swing sideways (a trailer jackknife), the only effective recovery is to immediately release the service brakes. Steering inputs do not correct a trailer skid because the trailer's lateral movement is governed by its locked tires lacking cornering grip, not by the tractor's heading.

Step-by-Step Solution

1
Identify the specific type of traction loss occurring in the scenario.
The scenario explicitly describes trailer tires locking and swinging laterally, which defines a trailer jackknife.
Different types of skids (front-wheel, drive-wheel, trailer) require entirely different physical recovery techniques.
2
Evaluate the proposed recovery action against standard CDL physics and guidelines.
The proposed action (rapid counter-steer) is the correct response for a tractor drive-wheel skid, but it is incorrect and ineffective for this specific emergency.
Steering inputs at the tractor cannot physically force a sliding trailer back into alignment. To recover from a trailer jackknife, the service brakes must be released to allow the trailer tires to roll, which is the only way they can regain lateral grip.

Key Concept

Trailer Jackknife Recovery vs. Tractor Drive-Wheel Skid Recovery
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Topics

Skid Control and Recovery

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