The U.S. Defense Advanced Research Projects Agency (DARPA) tapped Boeing Phantom Works to develop and demonstrate a large, solar-powered unmanned aerial vehicle (UAV) capable of staying aloft in the upper atmosphere for at least five years, according to a Sept. 16 Boeing press release.

Under the $89 million contract, St. Louis-based Boeing will build a full-scale demonstrator of the SolarEagle UAV under the agency’s Vulture 2 program. The aircraft’s wing, 120 meters across from tip to tip, will be outfitted with solar panels and fuel cells to power the craft through the night. For the first demonstration flight, scheduled for 2014, SolarEagle will attempt to fly at altitudes above 18,000 meters for 30 days, the press release said. Key suppliers to Boeing will be QinetiQ of the United Kingdom and Versa Power Systems of Littleton, Colo.