?At approximately 11:20 a.m. on June 19, 1970, a 1967 Ford Mustang, occupied by two young men, skidded into and under the rear end of a heavily loaded 1965 Ford flatbed truck, which was stopped in the middle of the three northbound lanes on Interstate 1-495, just north of Maryland Route 450 near New Carrollton, Maryland. The two occupants of the automobile died as a result of the injuries received in the collision. The truck, traveling north in the right (slow) lane on 1-495, was carrying a load of concrete pipe. The engine hood was held closed by a piece of baling wire in lieu of the broken hood latch. Suddenly the baling wire broke, allowing the hood to fly up in front of the windshield. The driver, unable to see where he was going, applied the brakes firmly, pulled into the middle lane, and stopped the truck. The automobile hit the rear of the truck. The road was dry and the weather was clear and sunny. There were no view obstructions other than the vehicles on the highway. The fatalities in this collision were caused by the absence of any form of rear-end crash protection on the truck, which permitted the automobile to underride the high frame of the truck and allowed the truck frame to enter the passenger compartment through the windshield, nullifying the intended protective effect of the occupants' fastened seat belts.