It's a truly scary moment: You are driving a long distance and suddenly realize you're nodding off.
According to a study by the AAA Foundation for Traffic Safety, Washington, D.C., one of six fatal U.S. crashes involves sleepy drivers. But safety technology now beginning to be installed in new cars warns drowsy drivers and may help them to avoid crashes.
The new systems work in two different ways:
To see how one of them works, let's look at my experience in a new Hyundai Equus. On an interstate highway north of New York, I steer the car to simulate drifting into the unoccupied lane on my left. A chime starts sounding. I move farther into the wrong lane, and my seat belt tugs at me sharply. If I had been drowsy, the system likely would have startled me awake.
In releasing its new crash test system, the National Highway Traffic Safety Administration, Washington, D.C., recommends that car shoppers consider crash avoidance systems like lane departure and forward collision warnings, as well as the more widespread electronic stability control, which helps prevent rollovers and is now available on most cars. The Insurance Institute for Highway Safety (IIHS), Arlington, Va., found from accident data that stability control systems already installed can reduce fatal single-vehicle crashes by half (49%).
The new systems are too recent to have real-world data. But IIHS analysts project that if these and other new technologies became widespread among U.S. vehicles, they might prevent more than one-third of fatal crashes.
As with electronic stability control, advanced safety features typically have started with luxury models, then moved down to less expensive vehicles. "We expect these new systems to be on many mainstream models within a few years," says Russ Rader, IIHS vice president of communications, but adds that the real-world impact will depend on how drivers respond to the new technologies.
Here's a closer look at three of the new technologies and which cars offer them as either standard or optional equipment, according to data compiled by Edmunds.com.
Of all the new systems, IIHS rates this the most likely to reduce fatal accidents—possibly avoiding up to 10,000 fatalities a year. Cameras in the vehicle monitor lane markers and signal if you're drifting out of the lane. All systems have audible chimes or beeps of some kind. Some brands, including Mercedes-Benz and BMW, use vibrating steering wheels instead of Hyundai's seat belt tug to alert drivers. When you're driving wide awake, the warning can go off annoyingly often for just a minor drift. But in most systems you can turn it off. Even when activated, it stays mute if you change lanes after putting on your turn signal.
Lane departure technology is available for 2011 models in the new Audi A8, BMW 5 and 7 series, Mercedes-Benz E-Class and S-Class, Cadillac STS and DTS, several Infiniti models, and the Volvo S60 and S80. The nonluxury Buick Lucerne also includes the technology, and the Chevrolet Equinox SUV will offer it as an option on 2012 models.
This system uses radar sensors to tell when you are so close to a vehicle ahead and closing so fast that a crash is imminent. A loud signal goes off and the car either activates the brakes slightly (Hyundai) or hits them hard (Mercedes-Benz). This warning usually is integrated with adaptive or "smart" cruise control, which will keep you a fixed distance from the car ahead when activated. I had no inclination to try the collision warning system in the Hyundai Equus. But the smart cruise control noticeably braked the car when another vehicle changed lanes just in front of me, thus reducing the previous safe distance.
Among all types of crashes—not just fatal—the IIHS report suggests that this could prevent or lessen as many as 2.3 million crashes a year and help avoid about 7,000 fatalities if the technology became really widespread.
The Acura MDX SUV, as well as the Audi 8, Infiniti, Lexus, Mercedes-Benz, and Volvo models offer collision warning. And among nonpremium brands, the Ford Taurus, Ford Edge and Explorer SUVs, as well as the Toyota Sienna minivan have the technology. At Chrysler, 2012 versions of the Chrysler 300 and Dodge Charger and Durango already offer this safety feature. The 2012 Chevy Equinox will add this one, too.
Though not specifically cited by NHTSA, these headlights that turn with the steering to illuminate curving roads at night might help prevent 2,500 fatal crashes a year, according to IIHS. Standard headlights shine straight ahead no matter how you are turning and often illuminate the roadside more than the pavement on winding roads. Adaptive headlights angle to the right or left when you turn the steering wheel to give you a better chance of seeing a deer or stopped vehicle in the road ahead.
Adaptive headlights are available on many Audi, BMW, Infiniti, Lexus, Mercedes-Benz, and Volvo models, as well as the Cadillac CTS, the Hyundai Genesis and Equus, and three Lincoln models. Among nonluxury brands, Volkswagen offers the technology on most models.
Of course, the best technology can't be as effective as just avoiding driving when you are sleepy. A AAA survey found that 41% of respondents said they had fallen asleep or nodded off when driving at some point in their lives. The study by the AAA Foundation for Traffic Safety suggests always getting at least six hours of sleep before a long drive, driving at a time when you are normally awake, and scheduling a break every two hours or 100 miles.