Boeing has successfully completed tests for a hydrogen propulsion for future aircrafts. The craft entitled HALE is an extreme endurance plane that will be able to fly for seven days non-stop in the stratosphere. The engine was developed by the Ford Motor Company and was tested for three days under the simulated conditions of a 65,000-feet flight.Chris Haddox of Boeing's Advanced Systems has said that it may be "several years before HALE flies" however, even while the hydrogen engines look like a good option for reducing carbon emissions, we ought not expect this technology to hit a Dreamliner anytime soon. It's primary purpose is communications for military or commercial purposes. Since it will be able to stay aloft for seven plus days, it would also be used for persistent intelligence, surveillance, reconnaissance purposes. The long endurance autonomous aircraft will be a propeller-driven, lightweight structure with a high-aspect-ratio-wing.
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