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Zorluk: OrtaStopping and Braking Procedures

While operating a commercial motor vehicle on a highway made slick by steady rainfall, the driver prepares to slow down and come to a complete stop for a red traffic signal ahead. What procedure should the driver follow regarding the auxiliary retarder system?

  1. A
    Maintain maximum retarder engagement to shorten the mechanical braking distance and reduce friction wear on the brake linings.
  2. Turn off the auxiliary retarder system and use the service brakes smoothly to prevent drive-wheel lockup and skidding.Cevap
  3. C
    Rely exclusively on the auxiliary retarder to bring the vehicle to a halt, assuming perception and reaction distances do not apply when retarders operate.
  4. D
    Apply abrupt full service brake pressure alongside the active retarder to verify that brake pushrods have not exceeded maximum stroke limits.

Cevap

Turn off the auxiliary retarder system and use the service brakes smoothly to prevent drive-wheel lockup and skidding.
Auxiliary retarders apply significant braking torque directly to the drive axle whenever the driver releases the accelerator. On wet, icy, or snow-covered surfaces where road friction is compromised, this unmodulated deceleration can cause the drive wheels to lose grip instantly, precipitating a dangerous drive-wheel skid or jackknife. Standard CDL operating procedures dictate turning off all auxiliary retarders in wet or slippery conditions and bringing the vehicle to a stop using smooth, progressive service brake application.

Adım Adım Çözüm

1
Assess the prevailing road surface condition and environmental factors.
Identify that steady rainfall has significantly reduced tire-to-road friction.
Reduced traction requires modifying vehicle braking and speed management strategies.
2
Determine the operational status required for the auxiliary braking system.
Disengage or switch off the auxiliary engine or driveline retarder.
Retarders apply continuous braking force to drive wheels; when traction is low, this torque easily induces drive-wheel skids.
3
Execute the stopping maneuver using modulated service brakes.
Bring the commercial vehicle to a smooth, controlled halt before the intersection.
Gradual application of service brakes maintains directional control and prevents wheel lockup.

Anahtar Kavram

Safe Auxiliary Retarder Management and Stopping Procedures in Wet Weather
Tahmini Süre:1m 0s
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Konular

Stopping and Braking Procedures

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