One of the deadliest kinds of semi-truck accidents occurs when a smaller vehicle collides with the back of a truck's trailer. Federal law requires most semi-trailers to be equipped with underride guards, which are metal bars that are designed to stop smaller passenger vehicles from sliding underneath trailers when collisions occur. However, as our Springfield semi-truck accident lawyers know, these guards don't always work.
In early March, the Los Angeles Fire Department released shocking photos of a wrecked Corvette that had rear-ended a moving box truck. The Corvette is shown pinned underneath the truck up to its rear axles, its top completely torn off. Authorities say the only reason the driver survived is because he had the presence of mind to duck immediately prior to impact. Miraculously, he escaped with only minor injuries - but it's apparent that the truck's underride guard didn't do its job.
Recently, researchers from the Insurance Institute for Highway Safety (IIHS) conducted a series of crash tests on trailers built by the industry's eight largest manufacturers. These tests specifically examined the functionality of each trailer's underride guard. Here's what they found:
• All eight trailers passed the first crash test, in which a 2010 Chevrolet Malibu rear-ended the center of a parked truck's trailer at a speed of 35 miles per hour.
• Seven trailers passed the second crash test, in which only half the width of the Malibu struck the back of the trailer.
• Only one trailer passed the third and toughest test, in which only 30% of the Malibu overlapped with the back of the trailer. According to the IIHS's news release, a 30% overlap is used "for the most challenging underride test because it is the minimum overlap under which a passenger vehicle occupant's head is likely to strike a trailer if an underride guard fails."
"When an underride guard fails, it's a very devastating crash," explains David Zuby, chief research officer for the IIHS. "The first point of impact is on the windshield. Then the top of the passenger compartment is sheared off."
Semi-truck accidents and underride guards: The facts
• In 2011, 2,241 passenger vehicle occupants died in collisions involving semi-trucks. Of that number, 260 were killed when their vehicles struck the rear of the truck's trailer.
• A 2011 study of 115 collisions between cars and semis found that approximately four-fifths resulted in underride. Of the 28 fatal accidents examined in the study, 23 occurred in cars with the most underride.