April 19, 2004
Stung by bad publicity about sport utility vehicles' propensity to rollover, American automakers have been blaming the rising death toll on tires and poor driving habits. European manufacturers have made the roofs of their SUVs even stronger than the roofs of their passenger cars, which far exceed their American counterparts.
When Volvo was preparing to introduce its XC-90 SUV, it invited reporters to a demonstration. An XC-90 was loaded on a cart that accelerated to 30 mph then stopped suddenly. The XC-90 rolled three times. When it was over, the roof was creased but structurally sound.
The Volvo's roof is reinforced with boron steel, an alloy that's as much as 50 percent more expensive than conventional steel. As a result, the vehicle exceeds U.S. requirements by more than 100 percent.
The Volvo SUV also includes rollover sensors that tighten seat belts automatically and side-curtain air bags along all three rows of seats.
Other European automakers take similar measures to strengthen rooftops and protect passengers, the Detroit News reported in a recent series on rollover safety.
American manufacturers, on the other hand, don't use the dolly test and don't spend as much to reinforce their roofs. In fact, many roofs have been "designed down" in recent years to reduce weight and thus increase fuel efficiency at the expense of safety, the newspaper said.
Ford uses the government's basic roof-crush test developed 33 years ago. In that test, pressure is gradually applied to a steel plate on one side of the roof. Critics say that doesn't begin to emulate the forces generated in a real-world rollover.
Case files show numerous U.S. models on the roads today can collapse in crashes of less intensity than the Volvo test crash, according to Carl Nash, a former director of strategic planning at the National Highway Traffic Safety Administration who now consults on roof-crush lawsuits. The damage is especially severe if a roof impacts the ground a second time, he said.
Its a clear safety problem, Nash said. Its absolutely, abundantly clear.
