Solar powered plane flies for 26 hours

Source New York Times

Slender as a stick insect, a solar-powered experimental airplane with a huge wing span completed its first test flight of more than 24 hours on Thursday, powered overnight by energy collected from the sun during a day aloft over Switzerland. The organizers said the flight was the longest and highest by a solar-powered craft, reaching an altitude of just over 28,000 feet above sea level, at an average speed of 23 knots, around 25 miles per hour. The plane–Solar Impulse–landed where it had taken off 26 hours and 9 minutes earlier at Payerne, 30 miles southwest of the capital, Bern, after gliding and looping over the Jura Mountains, its 12,000 solar cells absorbing energy to keep its batteries charged when the sun went down. The pilot, André Borschberg, 57, a former Swiss air force fighter pilot, flew the plane from a cramped, single-seat cockpit, buffeted by low-level turbulence after takeoff and chilled by low temperatures overnight.