The Helios Prototype is an enlarged version of the Centurion flying wing, which flew a series of test flights at NASA's Dryden Flight Research Center in late 1998.
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The solar-electric Helios Prototype flying wing is shown near the Hawaiian islands of Niihau and Lehua during its first test flight on solar power from the U.S. Navy’s Pacific Missile Range Facility on Kauai, Hawaii, July 14, 2001. The 18-hour flight was a functional checkout of the aircraft’s systems and performance in preparation for an attempt to reach sustained flight at 100,000 feet altitude later this summer.July 14, 2001NASA Photo / Nick Galante/PMRF› Helios Project Description