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What is the 'crack-the-whip' effect in doubles and triples?
- A.The last trailer always travels in a perfectly straight line
- B.Sudden steering moves are amplified toward the rear, so the last trailer swings the most and is the most likely to roll over
- C.It describes the sound a loose safety chain makes
- D.It is the extra speed the rear trailer gains downhill
Correct answer
B. Sudden steering moves are amplified toward the rear, so the last trailer swings the most and is the most likely to roll over
Why
Each unit in a set reacts later and swings wider than the one ahead of it, so the rearmost trailer gets the largest swing of all. Gentle, early steering is how the driver keeps that amplification small.
Manual topic: Combination Vehicles - Doubles and Triples · From the Combination Vehicles practice bank (CV-212).