Crash test intensifies call for side bumpers on tractor-trailers

The Chevrolet Malibu raced toward the side of a tractor-trailer at 40 mph. Its hood crumpled like an accordion when it slammed into the truck, but the car did not slide under the trailer and the airbag cushioned the head of the occupant in the front seat, in this case a crash dummy. This was a test of a side underride safety guard, a steel bumper system to protect against often fatal collisions between cars and trucks.