There’s a giant pothole in the road for drivers of oversized vehicles: new government ratings show that in single-car accidents, many sport utility vehicles are more likely to roll over than cars or light trucks.
For the first time, the National Highway Traffic Safety Administration has come out and said which new cars and light trucks are most and least likely to roll over in an accident. The data has a significant link to fatalities on the road. Single-car rollovers account for just six percent of all accidents, but they are responsible for 30 percent of car-accident deaths.
In its report, the National Highway Traffic Safety Administration rated 34 vehicles, including sport utility vehicles (SUVs), pickups, minivans and passenger cars, on a system of one to five stars, based on how likely the vehicle is to roll over, if involved in a single-car accident. All of the ratings were for model year 2001 vehicles.
Honda Accord Receives Perfect Rating Under the new rating system, the Honda Accord is the only vehicle to receive a perfect 5-star rating for safety. Most passenger cars received a 4-star rating and most SUVs received one or two stars, although some earned three.
All the pickup trucks and minivans received either three or four stars. The worst-performing vehicles, the only ones to receive a single star, were the Chevrolet Blazer 4x2, and the GMC Jimmy/Envoy 4x2.
But the surprise in the data was that some SUVs performed as well as minivans, and some pickups were as stable as passenger cars.
The ratings are based on a simple engineering test, with the results then compared to real-world crash data, which is based on nearly 200,000 police accident reports. Engineers came up with the data using a formula that combines the vehicle’s center of gravity and the width between the front tires to produce a stability rating.
The higher the center of gravity and the narrower the width between the front tires, the more likely the vehicle is to roll. NHTSA then compares the stability rating to the stability of past vehicles involved in accidents.
SUV Rollovers More Fatal Than Car Rollovers
There are more than 200,000 single-vehicle rollover accidents each year, according to NHTSA statistics. In 1997, about 10,000 people were killed in such accidents.
The data also shows that people are far more likely to die in SUV rollovers than passenger car rollovers. The single-vehicle rollover death rate for SUVs is nearly five times the rate in the largest cars (123 deaths per million vehicles, compared to 26).
In passenger cars, 22 percent of all fatalities occur in rollover accidents, but in SUVs, the figure is 64 percent, NHTSA officials say. One reason for the disparity is that SUVs are safer in other crashes, so there are fewer non-rollover deaths.
But when used to transport a heavy load or many passengers, SUVs are even more top-heavy, and thus unstable and prone to roll over.
Ratings Designed to Prompt Safer Designs
Newer SUV models are being built safer, according to the NHTSA. For instance, the 2001 Ford Explorer received two stars on the rollover criteria, but next year’s model will ride closer to the ground, and will sport a wider wheel base and a new suspension system that improves handling.
Though automakers say that such ratings can be misleading, they tend to heed the government’s call for safer standards. In 1979, just a third of all cars received a 4 or 5-star rating in crash tests, but by 1997, 85 percent were getting top ratings.