A runaway semi-truck is one of the scariest sights on the road, but it is made even scarier if the truck begins to jackknife.
The term “jackknife” describes the phenomenon of a runaway truck folding at the joint that connects the rig to the trailer. The end shape, with the rig and trailer facing opposite directions, vaguely resembles a type of foldable utility knife sometimes called a “jackknife.”
A jackknifing truck has a unique capacity for roadway destruction. When a jackknife occurs, it becomes almost impossible for the driver to maneuver or direct the vehicle in anyway. The truck is sent careening down the road, its trailer swinging violently like a giant pendulum, smashing anything that crosses its path.
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