New Ford safety system aimed at reducing SUV crashes

Ford has announced a new safety system, called Curve Control, which is designed to enhance the capabilities of its electronic stability control system in keeping a vehicle under control if a driver has entered a turn too fast. It will be standard on the redesigned Ford Explorer SUV when it arrives in early 2011, and will be offered on 90 percent of its SUVs, pickups, and vans by 2015.

Curve Control is designed to help slow a vehicle quickly in an understeer situation, before the conventional ESC has to kick in. Ford says that Curve Control is especially effective on highway exit and entrance ramps.

Like ESC, the system compares the steering angle to the path that the vehicle is following through a turn. If it senses understeer, Curve Control cuts the throttle and can apply varying amounts of brake pressure on each one of the four wheels to quickly slow the vehicle and keep it on course. Ford says the system works in wet or dry conditions and can slow a vehicle by up to ten mph in about one second. The system turns on the brake lights to alert other motorists.

A Ford representative told us that Curve Control takes ESC "to the next level," because most ESC systems are targeted at minimizing the risk of oversteer, which is when the vehicle's rear end slides out. Because of this, he said, those systems are not designed to scrub off speed quickly. A quick application of brakes in an oversteer situation could make the skid worse and increase the risk of a crash or rollover. With the addition of Curve Control, Ford's ESC will react differently to understeer and oversteer situations.

In our experience, some early ESC systems seemed more effective at combating oversteer than understeer, but many good ones now help in either situation.

SUVs are generally more susceptible to slides and rollovers than passenger cars due to their typically higher center of gravity, greater height, weight and sometimes tire choice. And rollover risk increases if a SUV strikes a curb while sliding.

According to the Insurance Institute for Highway Safety (IIHS) more than 10,000 people are killed in vehicle rollovers every year. About 25 percent of those are crashes involving cars or minivans. But more than twice as many fatalities, or 59 percent, are the result of SUV rollovers.

We welcome any developments that can further enhance vehicle safety. We'll be purchasing and testing a new Explorer as soon as it becomes available, and we'll let you know how Curve Control works at the test track.

—Jim Travers