The Year in Science: Technology 1997

The sound barrier has finally been broken—on land. Last October, British driver Any Green managed to keep his supersonic car, Thrust SSC, firmly on the ground as it sped down a 14-mile course in the Black Rock desert of Nevada. In the cool of the morning, when the speed of sound was 748 miles per hour, Green clocked in at an average of 763 mph over two runs. The car, designed by team leader and previous land-speed recordholder Richard Noble ck, is really more of a land-bound plane. It’s two jet engines generate 110,000 horsepower—about a thousand times more than a Ford Escort—guzzle 5 gallons of fuel a second, and take about thirty seconds to get the 54-foot-long, 7-ton car up to supersonic speeds. Even the driver, Green, is a former fighter pilot for the Royal Air Force. Although Chuck Yeager did it long ago in the air, breaking the sound barrier on land has posed its own problems. Not least, engineers have had a heck of a time counteracting the lift that occurs when air rushes over the car’s contours, forcing it upwards. And they know next to nothing about the effect shock waves would have on a supersonic vehicle so close to the ground. Noble and company solved these problems largely by trial and error over a period of tk years. Getting the record itself was brilliant, says James Morton, design director of G Force, the British firm that built the car, but they made it look too easy.