About SUVs
SUV accidents preventable with adjustments
Proving rollover risk
The SUV battle

In 1999 nearly one-third of the 35,000 fatalities from traffic accidents resulted from rollovers. SUVs are significant predictor of those fatalities - SUVs are three times as likely as passenger cars to flip over.

Center of Gravity
Passenger cars rarely flip over because they have a low center of gravity. The center of gravity is the absolute balance point in an object - the place equal forces exert right and left, front to back, and top to bottom. If an object were to be suspended from its center of gravity, it would not imbalance or even wobble.

Rollovers happen most often when a car is turning, and good suspension, shocks, and tires can help minimize this risk of accidents. However, the real predictor is a comparison between the height of the center of gravity and the vehicle's track width (the distance between the center of two tires on the same axle).

Experts present us with a simple formula - a predictor of rollover risk:

½ track width / height of vehicle's center of gravity

The result of the formula is known as the static stability factor, a number seen to be alarmingly high in many SUVs.

Cars that are built very low to the ground are exceptionally stable. Race cars are a good example, but not for realistic road conditions. Just inches off the ground, the underside of a race cars would be held up on the first bump. Passenger cars are therefore built with centers of gravity roughly twenty inches off the ground.

Unfortunately, SUVs are built with centers of gravity still higher off the ground by another five to six inches. Additionally, SUVs are often made with a track width narrower than passenger cars by two or three inches. The amount seems small until plugged into our formula, where results show a starker picture.

Compare one SUV measured at a track width of 58.6 and a center of gravity 27.53 inches off the ground and a passenger car by the same manufacturer with 61.9 and 21.7. The comparative static stability factors are 1.43 and 1.06. The comparison demonstrates a rollover risk of 37% for the SUV and 10.6% for the passenger car.

Other Dangers
We more accurately sense speed in cars built lower to the ground. SUVs seem to travel slower when we are more removed from the road. Experts guess that 60 mph in a passenger car feels similar to 40 mph in an SUV. Because of this peculiarity, SUV drivers sometimes take turns too fast.

Roofs of SUVs cave in much more easily than in passenger cars because the roofs are considerably higher than those of passenger cars. They impact the ground roughly instead of rolling through, as passenger cars roofs often do. People are often fatally crushed in SUV rollover accidents.

Safety Measures are Being Taken
Ford has increased the track width of its Ford Explorer by two and a half inches, an improvement to be certain, but the Explorer is still much less stable than the Ford Taurus.

Ford also is improving the suspensions in its Explorers. A new suspension with allow each wheel to react individually to the road, creating a safer ride. New Explorers have side curtain airbags as well.