Boeing Phantom Eye HALE Completes Vibration Tests

Phantom Eye's two hydrogen fuel tanks also were successfully filled with nitrogen to test fueling procedures and the aircraft's full-fuel weight configuration.
Phantom Eye has a 150-foot wingspan and is powered by two 2.3-liter, four-cylinder hydrogen engines that each provide 150 horsepower. It is designed to fly at 65,000 feet for up to four days; perform intelligence, surveillance and reconnaissance missions; and serve as a communications relay.
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