Flight On Solar And Battery Power Only Over 24 Hours

ANN Update 0930 EDT 07.08.10 The Solar Impulse aircraft landed back at Payerne, Switzerland precisely (because that's how the Swiss do things) at 0800 local time, after flying more than 24 hours powered only by electricity from solar cells.

The London Telegraph reports that pilot and co-founder Andre Borschberg flew over the Jura mountains for more than a full day, reaching an altitude of around FL285. The aircraft reportedly had about 3 hours left on its batteries when the sun rose over Switzerland.

Solar Impulse co-founder Bertrand Piccard said the flight proves that an airplane can stay aloft almost indefinitely. "Nothing can prevent us from another day and night... and the myth of perpetual flight," he said.

Original Story: The Solar Impulse aircraft lifted off at 0700 Central European Time Wednesday from Payerne, Switzerland for its delayed attempt to fly for 24 hours powered only by the sun and on-board batteries.

The team had planned to make the flight last week, but a technical glitch forced them to postpone the flight until Wednesday. "You have to understand that the airplane is completely experimental," said Solar Impulse co-founder Bertrand Piccard. "It is the type of airplane that has never flown in the past, so we need to assist the pilot from the ground, but we also need to assist the airplane itself."

The Voice of America reports that telemetry from the aircraft will tell ground crew about such things as wing vibration and flutter, the position of the flight controls, power levels, and solar cell efficiency.

The 24 hour flight requires a long period of daylight and very stable weather, and conditions in July in Switzerland are ideal, according to pilot and co-founder Andre Borschberg.

The flight plan calls for the aircraft to fly to an altitude of about 25,000 feet, and then slowly spend that altitude as energy during the night. It will also use energy stored in onboard batteries to keep the propellers turning.

The ultimate goal is to build a solar-powered airplane that will fly around the world. The aircraft being flown this week is a prototype, and construction is expected to begin on the next generation solar impulse soon.

FMI: www.solarimpulse.com