The California company said batteries were used to power the hybrid-electric aircraft and to approximate full aircraft weight and center of gravity for flight control, performance and responsiveness evaluation.
The demonstration phase for the system will now move toward hydrogen-fueled flight testing.
"These successful flights validated Global Observer's airworthiness and represent critical milestones as the team proceeds toward demonstrating stratospheric, extreme endurance operations," said Tim Conver, AV's president and chief executive officer. "The liquid-hydrogen fueled flight test series will be historic for AV and the JCTD team as Global Observer moves closer to demonstrating mission-readiness and supporting our troops whenever and wherever needed."
JCTD, or Joint Capability Technology Demonstrations, is a unit of the U.S. Department of Defense.
The primary objectives for initial flight testing were to test guidance, manual and autonomous controls, navigation, structural performance, thrust levels and handling in various winds and turbulence conditions.
AV also has successfully operated Global Observer's hydrogen-fueled generator for more than 1,500 hours in a specialized environmental chamber, including an uninterrupted seven-day mission cycle
AV is developing the Global Observer unmanned aircraft system to be the first to provide robust, cost-effective and persistent communications and surveillance over any location. Six U.S. government agencies have provided funding for the program.