First 24 hours solar flight underway

[kugga]

The first manned flight by a plane powered exclusively by solar energy designed to fly for 24 hours has been launched in Switzerland.
The aircraft has been mainly constructed from carbon fiber and with a 60-metre wingspan, the plan needed only 80 meters to take off, powered by four electric motors. The plane can fly as high as 8500 meters while simultaneously charging its batteries for the night flight.
The prototype has been constructed from a cost of 100 million dollars of investment. The aircraft, which has 12,000 solar cells built into its wings, is the prototype for a plane intended to fly around the world without fuel in 2012.

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[Avatar]

Sounds impressive at only 100 million dollars for the project. I wonder what's the cruising speed ? This platform could be very useful if reliable.

 

[DesiGuy]

Sounds impressive at only 100 million dollars for the project. I wonder what's the cruising speed ? This platform could be very useful if reliable.

"With an official flight time of 26 hours and 9 minutes, the lightweight carbon fiber plane reached a a maximum altitude of 8,700 m (28,543 ft), a top speed of 68 knots (ground speed), an average speed of 23 knots. "