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What Is a Jackknife Truck Accident?

A common term in trucking, the term “jackknifing” refers to when either a semi-truck, tractor truck, or truck with attached trailer, skids and causes the trailer portion of the vehicle to swing out to one side and cause an accident. The position of the truck’s cab in relation to the trailer resembles a folding knife blade and is thus termed a “jackknife”. Most often, a jackknifing occurs when the truck’s wheels lock up and the truck driver either over adjusts during a sharp turn or during bad weather when the truck’s cab can lose traction.

A jackknife truck accidents can be fatal to a driver or passenger since the tractor, being the smaller component, can get crushed. If another vehicle, such as a car, happens to be in the way of a truck when it is jackknifing, then it can be crushed, killing or badly injuring the occupants of the car. A jackknifed truck can block the road and cause a massive traffic jam until it is towed away.

If you have been involved in a jackknife truck accident, call the truck accident lawyers at Wilshire Law Firm today: (800) 522-7274

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Jackknifing Is Among the Worst Types of Truck Accidents

Truck accidents occur frequently on our highways. Not all accidents are the same. There are head-on collisions, rear-end collisions, collisions caused by brake failure, and rollover accidents. All of the different types of potentially devastating accidents can occur to any vehicle, as every tractor trailer accident attorney can tell you. However, the type of accident known as jackknifing can only occur to tractor trailers, usually larger ones.

What causes a jackknife?

Jackknifing generally occurs when the drive wheels become locked for some reason while the front wheels and the wheels of the trailer keep spinning. It can happen due to several factors including improper braking, equipment failure and adverse road conditions.

  • Improper braking: In an emergency situation which requires quick braking, a truck driver has three braking options. He can lock the steering axle brakes, drive axles or trailer axles. If he chooses the steering axle brakes, the truck will move straight ahead regardless of the angle of the wheel, although the driver will not be able to setter the truck. If the driver chooses the drive axle, then the trailer may collide into the tractor causing it to jackknife.
  • Adverse road conditions: In a low traction situation, such as when the road is wet and slippery, the tractor’s drive axle can lock up while the trailer’s axle keeps rolling. The tractor loses its directional stability and the trailer rams into it, causing it to spin and fold.
  • Equipment failure: Brake failure is one of the main causes of jackknife. Big rigs use air brakes, which are a type of friction brake which uses compressed air to apply pressure on the brake pad. The problem with air brakes is that they are able to tolerate only up to 600 degrees Celsius. When the brake temperature crosses this limit, the brakes do not work properly. If the trailer axle brakes fail while the drive axle brakes are still working, then the brake balance causes the trailer to collide into the tractor.
  • Deliberate jackknifing: Sometimes, truck drivers deliberately jackknife their truck to avoid hitting another vehicle or going over a precipice.

Are there any anti-jackknife devices?

There are several anti-jackknife devices that help truck drivers avoid jackknifing. Some of the more effective ones include:

  • Anti-lock Braking System (ABS): In essence, an anti-lock braking system (ABS) “smartly” pumps the brakes for the driver, preventing the wheels from locking up and maximizing stopping power. Anti-lock brakes have reduced jackknife accidents significantly.
  • Electronic Brakeforce Distribution (EBD): An electronic brakeforce distribution (EBD) automatically varies the amount of force applied to individual wheels based on the speeding, loading and road conditions.
  • Electromagnetic brake: An electromagnetic brake (EM brake) slows or stops a vehicle using electromagnetic force to apply mechanical resistance.

Jackknifing accidents can be very dangerous. If you or a loved one has sustained major damages in a jackknifing accident, contact a tractor trailer accident attorney to discuss how you can get full and fair compensation for your injuries and other losses.

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