NASA CRAFT DESTROYED IN CRASH.

Byline: Staff and Wire Services

HONOLULU - A solar-powered NASA flying wing preparing to test a fuel-cell system for staying aloft for days was destroyed Thursday when it crashed about a half-hour into a checkout flight off Kauai.

The remotely controlled Helios Prototype, a delicate-looking craft with a 247-foot wingspan and a cruising speed of only 25 mph, crashed into the Pacific Ocean during a shakedown mission in preparation for a 40-hour test flight next month.

``We were flying at about the 8,000-foot altitude west of Kauai over the ocean and the aircraft simply broke up,'' said Alan Brown, a spokesman for NASA's Dryden Flight Research Center at Edwards Air Force Base, from where the project is overseen. ``We can't tell you what may have led to that.''

Helios, built and operated by Monrovia-based AeroVironment Inc., was part of a NASA effort to develop unmanned aircraft capable of flying at high altitudes for weeks or months. Such aircraft could be used almost like satellites, relaying telecommunications signals or carrying instruments for studying Earth and its atmosphere.

NASA plans to develop another Helios vehicle for continued solar aircraft research, Brown said.