The Boeing Phantom Eye high-altitude long-endurance unmanned air system completed its second flight on February 25, 2013 from Edwards AFB, California. The aircraft climbed to 8,000ft (2,438m) and reached a speed of 62kts (115km/h) in a 66-minute flight, twice the height and three times the length of its first flight. Boeing reported that no problems were encountered with handling or during landing - a rough landing at the end of its initial flight resulted in the company changing the undercarriage.

The prototype Boeing Phantom Eye undergoing taxi tests at Edwards AFB, California, on February 6, 2013.

Boeing's Phantom Eye high-altitude, long-endurance UAV completed 12 days of vibration and structural interaction tests in early June 2011. The trials were undertaken at NASA's Dryden Flight Research Center located on Edwards AFB, California. Phantom Eye will be powered by two 150hp (112kW) hydrogen-fuelled four-cylinder engines, which will allow it to fly up to 65,000ft (19,812m) for four days undertaking surveillance, intelligence and reconnaissance missions, or acting as a communications relay station.

10 марта 2012г. в США в авиабазе Эдвардс (шт. Калифорния) прошли первые пробежки БПЛА с силовой установкой на водородном топливе Phantom Eye, созданного компанией Boeing в сотрудничестве с NASA. Этот разведывательный аппарат с размахом крыла более 45 м сможет подниматься на высоту около 20000 м и оставаться в воздухе до четырех дней.

1 июня 2012г. в летно-исследовательском центре NASA на авиабазе Эдвардс (шт. Калифорния) совершил первый 28-минутный полет разведывательный БПЛА с силовой установкой на водородном топливе Boeing Phantom Eye. При посадке БПЛА подломил шасси и получил незначительные повреждения.

A computer generated image of Boeing's concept for a twin-engined High Altitude Long Endurance (HALE) unmanned air vehicle (UAV). Boeing announced on October 24, 2007 that, using a Ford Motor Company-developed hydrogen engine, it has successfully tested the hydrogen propulsion system for its HALE UAV. The engine was run for nearly four days in a controlled chamber at the Aurora Flight Sciences facility in Manassas, Virginia, including three days simulating conditions at 65,000ft. The Boeing HALE is designed to remain airborne for more than seven days and carry payloads of up to 2,000lbs for applications such as battlefield persistent intelligence, surveillance and reconnaissance, border observation, port security and telecommunications.