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Pulling Double/Triple Trailers

Pulling Double/Triple Trailers is a required knowledge area under 49 CFR 383.115(b), (c), and (d), covering handling differences such as the crack-the-whip effect and oscillatory sway.

Practice Pulling Double/Triple Trailers

6 Questions

  1. The federal required-knowledge list for the double/triple trailers endorsement names specific handling and stability characteristics an applicant must understand. Which set does 49 CFR 383.115(c) actually name?
  2. 49 CFR 383.115(d) requires a double/triple endorsement applicant to understand the problems a longer combination creates for other motorists in traffic. Which of these does that paragraph name?
  3. You are making up a set of doubles with one heavily loaded semitrailer and one light one. To handle as safely as possible once underway, where should the heavier trailer go?
  4. The crack-the-whip effect makes doubles and triples roll over more easily than a single-trailer rig. Which trailer in the combination carries the most risk, and what should the driver do about it?
  5. You are pulling a set of triples and approach a curve with a posted advisory speed you have driven comfortably many times in a tractor-semitrailer. How should you treat that speed?
  6. Why does a driver need extra caution pulling doubles and triples through bad weather, slick roads, and mountain grades?