Monday, Dec. 24, 1984

Winging It Backwards

It should not fly. Its stubby wings angle forward, putting them under immense stress. Indeed, it is so unstable that no pilot can react fast enough to keep it from dropping out of the sky. Yet the X-29A flew precisely as planned last Friday in its first test flight from California's Edwards Air Force Base. Pilot Chuck Sewell kept the X-29A aloft at 15,000 ft. for nearly an hour, maintaining a relatively slow speed of 270 m.p.h. His secret: three built-in computers checked all flight-control surfaces 40 times a second, automatically making adjustments to keep the plane airborne. "If I lose all the computers, the airplane self-destructs in two-tenths of a second," said Sewell. The Pentagon and the Grumman Corp. are gambling some $130 million that the design will eventually give U.S. pilots an advantage in future dogfights.