CDL · Doubles and triples
If you pull doubles or triples, which of the following is accurate?
Correct answer: A sudden jerk of the steering wheel can cause the rearmost trailer to roll over.
Answer options
- AOff-tracking lets a triple-trailer rig stop in a shorter distance than a five-axle tractor-semitrailer.
- BA sudden jerk of the steering wheel can cause the rearmost trailer to roll over. Correct
- CThe crack-the-whip effect makes the last trailer of a 100-foot triple more stable than a single semitrailer.
Why
The crack-the-whip effect magnifies each steering input as it travels back through the combination, so an abrupt turn of the wheel can flip the last trailer. Off-tracking has nothing to do with shorter stops, and the whip effect makes the rear trailer more likely to overturn, not less.
About this question
Topic: Doubles and triples License: CDL
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Where it applies: Asked in every state.
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This question is part of Pulling Doubles and Triples (24 questions). Take the full set and check your score.
Practice Pulling Doubles and TriplesMore questions from Pulling Doubles and Triples
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- A truck pulling double trailers is 100 feet long and moving at 30 mph. The pavement is dry and you can see well. At minimum, how many seconds of following space should you leave?
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- Pulling a set of doubles, you have to brake hard to keep from hitting something. Which braking method should you use?
- In a rig pulling two or more trailers, which trailer belongs in the spot right behind the tractor?
- How does the rollover risk of doubles and triples compare with that of single-trailer rigs?
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