Share this with your friends and followers:

During my legal career of over 30 years, I have seen and handled a countless number of jackknifed tractor trailer crash cases.

Nearly all of them have involved life altering or fatal injuries.

Big semi-trucks are a common sight on our public roads.  Although they are a vital part of our transportation system, they can also be very dangerous.  One of the most common types of tractor trailer crashes is called a jackknife.

Jackknife crash: when a semi-truck trailer skids towards the truck cab at a 90-degree angle.

The term comes from the look of the tractor-trailer after the crash – like a small folding knife.

Jackknife crashes may also be considered rollover crashes, although not all roll-overs end in a jackknife.

Rollover crash: when a driver loses control, and the truck slides and rolls over onto its side.

Jackknife tractor trailer causes

This type of crash can be caused by a number of factors, including the following.

Excessive speed. The average tractor-trailer weighs around 80,000 pounds. The average length of a trailer is between 70 – 80 feet.  It takes that vehicle much longer to stop: most trucks need 40% more time to stop compared to cars. When a truck driver is forced to stop too quickly, the trailer can slide sideways and jackknife.

Improper following distance. All too often, truck drivers do not provide an adequate following distance to allow for a safe stopping distance. When a truck driver has to slam on the brakes, the trailer can slide sideways and jackknife.

Operator fatigue. Many truck accidents crashes happen when a truck’s driver has logged too many hours behind the wheel without breaking for sufficient rest. When you’re tired, your response time suffers. If a truck driver is groggy behind the wheel, he or she may be unable to maneuver out of a dangerous situation.

Unbalanced load. A big part of safe trucking is making sure the trailer’s cargo is properly loaded and distributed. When cargo is unbalanced, it can shift, causing the trailer to tilt or tip. Unbalanced loads are often a factor in rollover crashes.

Inexperienced or untrained operator. Driving a truck is a demanding job that requires skill and experience. When truck companies try to lower costs by putting inexperienced drivers on the road, disasters can happen.

Bad weather. Jackknifes can happen when roads are slick or icy. In areas that receive very little rain, even a brief sprinkle can create hazardous road conditions, as accumulated oil can quickly grow slippery when it’s wet.

WSP-Semi truck crash tractor trailer rollover

Read more about the powdered milk truck crash on I-5.

Research and my experience makes it clear that jackknife crashes can cause widespread damage, as they  usually spread a tractor and trailer across multiple lanes of traffic. Because of this, there is the danger of secondary crashes – vehicles not initially involved in the crash, running into the tractor trailer or debris.

The Insurance Institute for Highway Safety (IIHS) shared the following statistical data from 2017:

  • A total of 4,102 people died in large truck crashes.
    • 17% of these deaths were truck occupants;
    • 68% were occupants of cars and other passenger vehicles;
    • 14%  were pedestrians, bicyclists or motorcyclists.
  • 52% of deaths in large truck crashes occurred on major roads other than interstates and freeways.

These statistics prove the seriousness of truck collisions and how common – and widespread – they have become.  Just over the past couple weeks, I have read about several rollover truck crashes, all over the Pacific Northwest.

With the winter weather upon us, if better care is not undertaken by truck drivers, many more will occur.

Attorney Kevin Coluccio 
Coluccio Law
Seattle, Washington


Learn more:


Here’s why semi-trucks jackknife

A more extensive explanation of the factors contributing to semi-truck crashes caused by a tractor-trailer jackknife.