Practice Test Geeks(CLP) Commercial Learner's Permit Practice Test
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Combination Vehicle Operations Flashcards

7 cards from real CLP practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.

Read the first 7 Combination Vehicle Operations flashcards as text

  1. What is the primary danger of trailer skid (trailer jackknife) in a combination vehicle?

    Answer: The trailer swings outward and can hit other vehicles

    During a trailer jackknife the trailer swings toward the cab, potentially striking other vehicles or causing a rollover.

  2. When should you test the trailer brakes using the hand valve (trolley valve) before a trip?

    Answer: At low speed in a safe area before leaving the terminal

    Test trailer brakes by applying the hand valve at low speed in a safe area to confirm the trailer brakes are functioning properly.

  3. What effect does adding a second trailer (doubles) have on the braking distance compared to a single trailer?

    Answer: Braking distance increases significantly due to added weight and rearward amplification

    Doubles have greater overall weight and rearward amplification effects, which substantially increase stopping distance.

  4. How do you release the fifth wheel locking jaws to uncouple a trailer?

    Answer: Pull the release handle while the trailer landing gear is down and the truck is slightly under the trailer

    The landing gear must support the trailer weight and the truck positioned correctly before pulling the fifth wheel release handle.

  5. What is 'rearward amplification' in a triple combination vehicle?

    Answer: The tendency of the last trailer to sway more violently than the first trailer during a lane change

    Rearward amplification means the last trailer in a triple can sway or tip at a much higher rate than the steering inputs or first trailer movement would suggest.

  6. When coupling a tractor to a trailer, at what height should the trailer nose be before backing under it?

    Answer: Slightly lower than the fifth wheel height so the fifth wheel rides up onto the trailer plate

    The trailer should be slightly lower than the fifth wheel so as the tractor backs under, the fifth wheel raises and engages the kingpin properly.

  7. What is the correct procedure if the trailer starts to jackknife during braking?

    Answer: Release the brakes immediately to allow the trailer wheels to regain traction

    Releasing the brakes allows the locked trailer wheels to begin rolling again and regain traction, helping to straighten the combination.