Automotive engineers spent decades working to make passenger cars safer in crashes, but the recently reported increase in U.S. highway fatalities shows that vehicle safety has become much more complicated. The emphasis is on two new fronts: preventing crashes and dealing with special issues posed by sport-utility vehicles.
Deaths in motor-vehicle accidents rose last year to 42,815, an increase of 619 over 2001 and the highest level since 1990, according to the National Highway Traffic Safety Administration. The rise capped a decade in which the rate of deaths per miles traveled leveled off after 25 years of falling.
The rise in deaths to vehicle occupants was even higher, 745 (the number of deaths for non-occupants fell by 126). SUVs, pickups and vans accounted for more than 60 percent of the rise in occupant deaths; 61 percent of deaths in SUVs occurred in rollovers, and 45 percent of pickup deaths were in rollovers.
Auto industry officials say light trucks are as safe as cars. “The most prevalent factors contributing to motor vehicle crashes are human factors,” said Robert Strassburger, vice president of vehicle safety for the Alliance of Automobile Manufacturers.
Strassburger noted that NHTSA’s most recent numbers showed that 59 percent of vehicle occupants killed in 2002 were not using restraints such as seat belts or child safety seats. If the U.S. could boost its seat belt usage from the current 75 percent to something like Canada’s 91 or 92 percent, he said, “that would save about 4,500 lives a year.”
Auto-safety advocates dispute such claims. “It’s not hard to figure out why the [fatality] trend has been reversed and is getting worse,” said Ralph Nader, whose 1960s car-safety crusade is widely credited with inspiring the era’s advances. “There’s a higher mix of SUVs and unstable vehicles in the entire fleet.”
Nader and other safety advocates are calling for the government to set roof crush standards for SUVs, and for carmakers to install roof-mounted air bags that can protect against head injuries in rollovers.
Clarence Ditlow, director of the Center for Auto Safety, applauded the recent popularity of car-based SUVs because their smaller, more forgiving frames pose less of a threat to other cars.
While the SUV debate rages, auto industry researchers are pushing into the more technologically demanding realm of designing vehicles that can avoid wrecks.
Some types of crash-avoidance systems are on the market, though they are more widely available in Europe than in the U.S.
Adaptive cruise control
Mercedes, Jaguar, Lexus and Infiniti offer “adaptive cruise control,” which uses radar or lasers to sense when other traffic is getting too close and make the car slow down.
Automakers, leery of liability issues that arise from a device that promises to drive more safely than a human, market the systems as a convenience.
Robert Ervin, head of engineering research at the University of Michigan Transportation Research Institute, is supervising the field-testing of a device that uses full-time radar to keep a car from hitting any obstacles.
The technology works, but the big mystery is how drivers will interact with it and how much control they are willing to surrender.
“It’s a tender thing to do with technology,” Ervin said.
“We can build processors to do this, but as soon as you tread into the arena of human behavior nobody knows what’s really going to happen.”
One of the most promising advances in crash avoidance is electronic stability control, said David Champion, head of automotive testing for Consumers Union, publisher of Consumer Reports magazine.
Such systems, widely available in Europe but offered on only a few U.S. luxury cars and SUVs, use gyroscopes and other sensors to judge when a vehicle is beginning to tip.
Then the system can apply brakes to individual wheels to prevent a rollover.
“I feel it should be standard on all SUVs,” said Champion, who has tested the systems.
Regulators at NHTSA also are taking a close look at stability control, the agency’s chief, Jeffrey Runge, said in an interview. “This is a really important technology that is not widely deployed in the fleet, and I really look forward to that and to seeing if it’s going to make a difference in the frequency of rollover crashes. I know it does on the test track,” he said.
Runge added that he is reluctant to require automakers to install such devices, saying the additional cost could make consumers delay buying a new vehicle and leave them driving longer in older, less safe cars and trucks.
General Motors, for example, charges roughly $500 for the electronic stability control system available on select models.
Human behavior
Some experts caution that even if reliable crash-avoidance systems become available, they will never offset dangerous vagaries of human behavior.
Advances in car safety often flounder against other factors that work to keep death rates up.
Anti-lock brakes, for example, have become common, but studies show people are using them to take more risks.
Cellphones, navigation computers and entertainment systems pose unprecedented distractions to drivers.
Drunken driving is up, as is speed and horsepower.
“You never know if an incremental upgrade [in safety] isn’t counterbalanced by a change in risk-taking by the people,” Ervin said.
“It’s like everybody has a certain total level of risk they’re willing to tolerate.”
`A statistical wall’
It’s possible, he said, that the nation’s fatality rate has hit a statistical wall, a level of death that cannot be improved upon without great expense and societal change.
In the mid-1960s, there were 5.5 deaths for every 100 million vehicle miles traveled.
Under pressure from consumer advocates and government regulators, the auto industry made fundamental safety changes, building cars that crumple around their occupants, installing better restraint systems and making air bags standard.
By 1992, the fatality rate had fallen by more than two-thirds, to 1.75.
“That’s one of the great success stories of federal intervention in public life,” Ervin said.
Over the next 10 years, though, the rate stopped its plunge and held almost steady.
It drifted to 1.51 and held there for 2001 and 2002, according to NHTSA’s preliminary statistics.
Part of the problem is that designers have made all the obvious, high-payoff changes that make people safer during a crash, said Thomas Dingus, director of the Virginia Tech Transportation Institute.
“It’s difficult now to make the same level of progress,” he said. Further engineering changes amount to either tinkering around the edges or adding significant weight and cost to each vehicle.
Nader disagreed.
“Thirty years ago these guys were saying the same thing,” he said.
“These guys are really incorrigible.”
