Jackknife accidents are among the most dangerous types of collisions involving large commercial trucks. They occur when the trailer of a truck swings out to form a sharp angle with the cab—resembling the shape of a folding pocketknife.
These crashes can lead to devastating, multi-vehicle pileups, serious injuries and even fatalities. While truck drivers often bear the brunt of responsibility, the actions of nearby passenger vehicles can also contribute to jackknifing.
1. Sudden braking or cutting off a truck
Unlike cars, fully loaded trucks need much more time and distance to come to a complete stop. When a car suddenly enters a truck’s lane and reduces speed, the truck driver may be forced to brake abruptly to avoid a collision.
This sudden braking can cause the trailer to swing outward, especially if:
- The road is slick
- The truck is lightly loaded
- The trailer brakes aren’t perfectly balanced
Once the trailer starts to skid out of alignment with the cab, the driver has very limited options to recover control.
2. Poor weather and road conditions
Rain, snow, ice and even high winds can reduce traction and stability. When a truck is traveling on a slick surface and tries to stop too quickly or change lanes, the tires may lose grip, causing the trailer to slide.
A car tailgating a truck or attempting to pass on a snowy or icy road can cause the truck driver to make a sudden move that initiates a skid. Worse yet, if a car hydroplanes and collides with a truck, the force can shift the trailer’s momentum enough to send it spinning into a jackknife.
3. Downhill grades and improper speed control
Long downhill stretches of road can be particularly hazardous for trucks, especially if the driver fails to use proper braking techniques. If the truck picks up too much speed going downhill and suddenly needs to brake, the risk of jackknifing increases significantly.
Swerving or braking suddenly near a descending truck can force the driver into a panic stop, and without careful modulation of the brakes, the trailer can swing out of control.
Jackknife accidents are violent and often preventable crashes that usually stem from a mix of mechanical forces and poor decision-making. Passenger vehicle drivers who get involved in these collisions may be confused as to which parties are to blame for the accident. With effective legal guidance, they can get to the bottom of the matter to help hold at-fault parties accountable for their recklessness.