Practice question

The first step in uncoupling a converter dolly is:

  1. To lower its landing gear.
  2. To raise its landing gear.
  3. To disconnect the air lines.
  4. To lock the brakes.

Answer: A — To lower its landing gear.

Lowering the landing gear is the first step because it puts the dolly on solid, independent support. This stabilizes the weight of the dolly and the trailer connection, preventing the dolly from tipping or shifting when you break the coupling. With the dolly resting on its legs, you can safely proceed to disconnect air lines and complete the uncoupling without the risk of movement or damage. Raising the landing gear would remove that support and make the uncoupling unstable, while addressing the air lines or brakes before the dolly is properly supported can lead to unintended movement.

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