RESEARCH TO EVALUATE SAFETY TECHNOLOGIES FOR VULNERABLE FUEL TANKS

In 1993, the US Department of Transportation ordered a recall of approximately 5,000,000 GM pickup trucks equipped with sidesaddle fuel tanks due to their alleged vulnerability in severe side crashes. The fuel tanks on these pickups were located under the cab and bed outside the frame rails. The recall was subsequently rescinded in favour of an administrative settlement. Prior to the settlement, NHTSA conducted a research program that included more than twenty crash tests. NHTSA defined a crash configuration that the pickups with sidesaddle tanks failed but competitive models of trucks passed. The test involved an 80 km/h (50 mph) side impact by a Chevrolet Caprice, in a breaking attitude, aligned so that it impacted the fuel tank at an angle of 30 degrees. In 1999, a follow-on project was undertaken by the Automotive Safety Research Institute (ASRI) to evaluate alternative tank systems to the sidesaddle design. The alternatives investigated included the following: providing a cage for tank protection, incorporating a fuel bladder, changing tank materials, and relocation of the tank. In conjunction with these design alternatives a number of other technologies were investigated, such as shielding of fuel lines, check valves, self-sealing break away fuel line couplings, and fire suppressant panels. Eighteen full-scale crash tests were conducted to evaluate the various technologies. The best test results were obtained by two strategies that moved the tank to less vulnerable locations. Tests of strategies that attempted to maintain the tank in its sidesaddle location were not successful. Break-away couplings in the fuel lines, a flapper valve in the filler tube and shielding of vulnerable fuel lines were tested under conditions that demonstrated their efficacy. Other technologies showed promise but were not fully developed and tested. For the covering abstract see ITRD E825082.