The Phantom Eye demonstrator, a Boeing-funded development effort, has proven the exceptional fuel economy of the liquid hydrogen propulsion system, producing only water as a byproduct. It is capable of maintaining the aircraft's altitude for up to four days while carrying a 450-pound payload. Typical payloads include multiple sensor packages for monitoring, tracking and communications. When properly equipped, Phantom Eye can relay information across its 400-nautical-mile line of sight horizon.
The demonstration vehicle completed its first medium-speed taxi test March 10, 2012, at Edwards Air Force Base, Calif., in coordination with the NASA Dryden Flight Research Center. Phantom Eye, traveling atop its launching cart system, reached speeds of up to 30 knots as ground teams relayed directions and information using Boeing's advanced Common Open-Mission Management Command and Control (COMC2) software.