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Most drivers understand that colliding with a commercial truck can cause catastrophic injuries. Far fewer have heard of an underride crash, even though this type of collision presents a particularly deadly risk to people in passenger vehicles.
Underride occurs when a smaller vehicle slides partially or completely underneath a large truck or trailer during a collision. Because the truck’s body sits higher than the passenger vehicle, the point of impact can move above the car’s hood and into the passenger compartment.
The consequences can be devastating. Understanding why these crashes happen, how underride protection is intended to reduce the danger, and what evidence should be investigated afterward can be critical for injured Texans and their families.
Why Are Underride Crashes So Dangerous?
Passenger vehicles are designed with structural components intended to absorb crash forces and protect occupants. In an underride collision, those protections may not work as intended because the smaller vehicle can travel beneath the higher truck or trailer.
Instead of the front of the passenger vehicle absorbing the impact, the truck may strike the windshield, roof, or passenger compartment.
These crashes can cause:
- Traumatic brain injuries.
- Spinal cord damage.
- Severe head and neck injuries.
- Crush injuries.
- Multiple fractures.
- Internal organ damage.
- Fatal injuries.
Underride can occur at the rear or side of a commercial vehicle. Rear crashes may happen when a passenger vehicle strikes a slow-moving or stopped trailer. Side underride can occur when a truck crosses, turns, or blocks traffic and a smaller vehicle travels underneath the side of the trailer.
What Is a Mansfield Guard?
Many people recognize the horizontal metal bar beneath the back of a semi-trailer without knowing its purpose. It is commonly called a Mansfield guard, although federal regulations generally refer to these devices as rear impact guards.
The guard is designed to help prevent a passenger vehicle from traveling underneath the trailer during a rear-end collision. By creating a lower point of contact, the guard can help the smaller vehicle’s crash-protection systems engage more effectively.
Federal safety standards require most qualifying trailers and semitrailers to have compliant rear impact guards. Current standards establish performance requirements intended to improve protection for occupants of passenger vehicles in certain rear underride crashes.
However, the presence of a guard alone does not mean it will provide effective protection in every collision.
When Underride Protection Fails
A rear impact guard must be capable of handling substantial crash forces. A guard that is damaged, improperly maintained, corroded, or otherwise inadequate may fail during a collision.
Investigators may need to determine whether:
- The required rear guard was present.
- The guard complied with applicable safety standards.
- Previous damage weakened the guard.
- Corrosion affected its structural integrity.
- The guard had been properly inspected and maintained.
- Repairs or modifications affected its performance.
The angle of the collision can also matter. Not every rear impact occurs directly in the center of a trailer, and crashes involving only part of the passenger vehicle’s front end may place different stresses on the guard.
Effective underride protection therefore involves more than attaching a metal bar to the back of a trailer. Its design, condition, installation, and maintenance may all become important after a serious collision.
Who May Be Responsible for an Underride Accident?
Liability depends on why the crash occurred and whether another party’s negligence contributed to it.
A truck driver may be responsible for unsafe driving that creates the collision, such as suddenly entering traffic, stopping in an unsafe location, or operating without adequate lighting or visibility.
A trucking company may face liability for negligent maintenance or for other conduct connected to the condition and operation of the commercial vehicle. Depending on the evidence, questions may also arise concerning the trailer owner, maintenance provider, or manufacturer of a defective component.
A thorough investigation should examine both why the vehicles collided and why underride occurred. Those are not necessarily the same question.
Evidence Can Reveal Why the Guard Failed
After a severe truck crash, the condition of the commercial vehicle can provide important evidence. Repairing, selling, or returning a trailer to service may alter or destroy information needed to determine what happened.
Evidence may include:
- Photographs and measurements from the crash scene.
- The truck and trailer themselves.
- The rear impact guard and its attachment points.
- Inspection and maintenance records.
- Previous repair records.
- Electronic logging and vehicle data.
- Dashcam or surveillance footage.
- Witness statements.
In some cases, engineers or accident reconstruction specialists may need to evaluate the guard, vehicle damage, and collision dynamics.
Preserving this evidence quickly can be particularly important when the effectiveness of rear impact guards is disputed.
Taking an Underride Crash Seriously From the Start
Underride accidents demonstrate why serious truck crashes require more than a review of the police report. Determining that one vehicle struck the back or side of a trailer does not necessarily explain why the collision occurred, whether required safety equipment functioned properly, or whether preventable failures contributed to the severity of the injuries.
At Glen Larson Law Injury Attorneys, we investigate serious commercial truck crashes and pursue evidence from trucking companies and other potentially responsible parties to determine what contributed to our clients’ injuries.
If you or a loved one was injured in an underride crash in Austin or elsewhere in Texas, call (512) 883-0277 or contact us online to schedule a free consultation today.
