Coupling & UncouplingQuestion 20 of 60
Which of the following is the correct sequence when coupling a tractor and trailer?
a.Raise landing gear, then back under, then connect air lines
b.Connect air lines, then tug test, then position tractor
c.Back under, raise landing gear, then set trailer height
d.Inspect and prepare, back under and couple, connect air lines and supply air, test coupling, raise landing gear
Explanation
The proper sequence is to inspect and prepare the equipment, back under and couple, connect and supply air lines, test the coupling with a tug test and visual check, then raise the landing gear. Following the correct order prevents a false coupling and dropped trailer. Skipping steps like the air connection or tug test is dangerous.
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Related questions on this topic
- Why should you use two low-pressure gears when starting to raise loaded landing gear rather than high gear?
- What should you check about the fifth wheel plate before backing under a trailer?
- Before coupling, why should you inspect the area around and under the trailer?
- What is the purpose of the safety catch on many fifth wheel release levers?
- If the trailer is too low when you back under it, what is the likely result?
- Why must you supply air to the trailer and check for air leaks before moving after coupling?
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