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Solar-Powered Spy Plane Stays Aloft for Over Three Days

80beatsBy Eliza StricklandAugust 25, 2008 5:39 PM


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An unmanned, solar-powered plane has unofficially broken the record for the longest uninterrupted flight, staying aloft for 82 hours and 37 minutes; it flew through the nights by drawing energy from batteries that it recharged during the day. Engineers for the high-tech aircraft, the Zephyr, say that the three-day flight is just the beginning of what it can do.

[T]he aircraft's designers, at the defence firm QinetiQ, in the UK, think the plane could fly indefinitely. "We think the aircraft, in future, will be capable of weeks or months duration," said Paul Davey [Guardian].

The flight was a demonstration for the U.S. military, which is interested in using the craft for reconnaissance and battlefield communications. But the Zephyr didn't officially break the record for the longest flight because representatives from the world air sports federation weren't on hand to observe the feat.

The flight beats the current official world record [for an uncrewed flight] of 30 hours, 24 minutes set by the US robot plane Global Hawk in 2001 [Telegraph].

The Zephyr has long, delicate wings that are covered in paper-thin solar arrays, and is made of an ultra-lightweight carbon-fiber material that keeps the craft's weight below 70 pounds. After its engineers launch it by hand, the Zephyr's propellers then carry it to an altitude of 60,000 feet, where it's flown by autopilot and via satellite communication. QinetiQ researchers say the Zephyr could mark a great leap forward in reconnaissance technology.

"The principal advantage is persistence - that you would be there all the time," [said QinetiQ engineer Chris Kelleher]. "A satellite goes over the same part of the Earth twice a day - and one of those is at night - so it's only really getting a snapshot of activity. Zephyr would be watching all day [BBC News]."

QinetiQ officials say the craft could be ready for battlefield deployment within two years. DISCOVER took a good look at the official record holder, the Global Hawk, in "Flying Blind." Image: QinetiQ

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