Practice question

What is the safest general order for building a set of doubles?

  1. Couple the tractor and first trailer, then position and connect the dolly, then couple the rear trailer
  2. Couple the rear trailer to the tractor first, then add the lead trailer
  3. Connect all air lines before making any mechanical couplings
  4. Raise all landing gear before any coupling is attempted

Answer: A — Couple the tractor and first trailer, then position and connect the dolly, then couple the rear trailer

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