Solar Impulse: Solar-powered plane makes airborne hop

The prototype of Solar Impulse, a pioneering Swiss bid to fly around the world on solar power, briefly took off for the first time on Thursday but under battery power, the organisers said.

The high tech single-seater with the wingspan of an Airbus A340 airliner (63.40 metres) made a controlled 400 metre (yard) flight about one metre above the runway at Duebendorf air base near the Swiss city of Zurich, said co-founders Bertrand Piccard and Andre Borschberg.

"A plane like that never flown before and it's extraordinary... because it's an area of flight that has been unexplored until now," Borschberg, chief executive of Solar Impulse, told AFP.

"It was very important to see if it would rise and what way we could keep it stable," he added.

Despite its wingspan, the aircraft only weighs 1,600 kilogrammes, about as much as a medium-sized car.

Although the prototype is fitted up for solar-powered flight, the four electric motors were powered by batteries for the occasion.

The prototype, which is slightly smaller than the craft that is expected to fly around the world, is primarily aimed at testing the cutting edge technology used to build and control the aircraft, and to fly through the night.

A first non-stop 36 hour flight through darkness is planned in Switzerland from spring 2010, with the prospect of a five stage flight around the world in 2012.