What does the term “jackknifing” refer to in commercial driving?

The term “jackknifing” in commercial driving refers to a situation where the trailer of a tractor-trailer swings out, forming an acute angle with the truck, resembling a jackknife. This typically occurs when the trailer loses traction, often on slippery surfaces, or during sudden braking. The risk of jackknifing is particularly high in adverse weather conditions or when a driver makes abrupt steering movements. It can lead to loss of control of the vehicle and poses a significant danger to both the driver and other road users, as the trailer can swing into adjacent lanes.

Understanding this concept is crucial for commercial drivers, as recognizing the early signs of potential jackknifing and taking corrective actions can prevent accidents. Proper techniques like maintaining safe speeds, especially on wet or icy roads, and being mindful of load distribution can help mitigate the risk of jackknifing.