October 8, 2003
NHTSA announces new rollover test
Washington, D.C. – Beginning with the 2004 model year, the U.S. Department of Transportation’s National Highway Traffic Safety Administration (NHTSA) will enhance its current rollover ratings system with the addition of a dynamic track test, the agency said yesterday.
After considering a number of alternatives, NHTSA has decided that the dynamic test will use the so-called “fishhook” maneuver – a series of abrupt turns at varying speeds. A computerized steering system will be used in each test vehicle to maintain objectivity.
In 2002, 10,666 people were killed in rollover crashes, up five percent from 2001. Sixty-one percent of all occupant fatalities in sport utility vehicles (SUVs) and 45 percent of pickup truck deaths were the result of a rollover crash. By contrast, 22 percent of passenger car fatalities in 2002 were the result of a rollover crash.
“Consumers need to consider rollover risk when they shop for a new vehicle,” said NHTSA Administrator Jeffrey W. Runge, M.D. “Our rating system will give them the information they need to make a wise choice.”
NHTSA’s current consumer program rates rollover risk based on a vehicle’s “static stability factor,” which is an engineering calculation based on the track width (the distance between two wheels on the same axle) and the height of the center of gravity above the road. Starting with the 2004 model year, the rollover risk predictions will be based both on the vehicle’s static stability factor and its performance in the dynamic test.
The rollover rating system – one to five stars – remains unchanged. One star is for rollover risk greater than 40 percent; five stars, 10 percent or less.
The Transportation Recall Enhancement, Accountability, and Documentation (TREAD) Act of 2000 required that NHTSA develop a dynamic test on rollovers to supplement an existing consumer information program. The agency has been providing consumers with vehicle rollover ratings since the 2001 model year as part of its New Car Assessment Program (NCAP).
Information on the enhanced rating system can be downloaded from the NHTSA site (pdf).