Solar Plane Beats World Record

A lightweight, solar-powered plane has broken the world record for the longest unmanned flight by a whole day. The Zephyr, built by a British security firm, flew for 54 hours during a test flight, beating the US Air Force's record for a similar vehicle by 24 hours. But it's not official: The air sports federation wasn't notified in time.

The organization was informed at the last minute of a second flight which lasted 33 hours, a figure that could still make the record books. The Zephyr, which the firm says could see military operations in the future, flies on solar power by day, and on solar-powered batteries by night. "You ain't seen nothing yet," the plane's technical director told the BBC. (More solar energy stories.)