Solar powered plane to fly across the US

A fully solar-powered airplane that flew from Spain to Morocco last June is set to fly across the US in five legs beginning 1 May.

The Solar Impulse HB-SIA, considered to be the world's most advanced solar plane, is made of carbon fibre and capable of flying at night. It has a wingspan similar to that of a Boeing 747-200 and weighs hardly 1,600 kilograms, just about the weight of an average family car.

The plane is powered by 12,000 solar cells driving four 10 hp electric motors. The average power available is just about that of a typical scooter and the advanced technology will allow the plane to fly for over 26 hours at a time.

The ambitious journey is about to begin on 1 May from Moffett airfield in Mountain View, California, although the actual departure will depend on the weather.

The voyage is likely to continue for about two months before ending at New York's Kennedy airport, covering a distance of up to 4,800 km.  On its journey, the plane will have long stops of 7 to 10 days at Phoenix, Dallas, St Louis or Nashville or Atlanta, and Washington DC.

Bertrand PiccardSwiss psychiatrist and balloonist Bertrand Piccard is the co-founder and pilot of the solar plane project, who circled the earth nonstop in a balloon in 1999.

André Borschberg, Solar Impulse's co-founder, co-pilot and CEO said, "This airplane could do it nonstop, but because the pilot is not as sustainable as the technology, we have limited ourselves to 24-hour flight duration."

"We want to inspire the young generation to become pioneers, to help them find and develop their passion," he said.

Solar Impulse's slim body design makes it highly susceptible to headwinds. The plane is expected to cruise at around 56 km per hour

If the journey across the US becomes successful, Solar Impulse will attempt to circle the earth in 2015 which could be extremely challenging with long non-stop stretches over the Pacific and Atlantic oceans. 

Once, when Piccard was asked, if solar impulse was the plane of the future, he said, "It would be crazy to answer yes, and stupid to answer no. Because today, we cannot imagine having a solar-powered airplane with 200 passengers. But in 1903, it was exactly the same. And when Charles Lindbergh crossed the Atlantic, he was alone on board, in an airplane full of gasoline. We don't know what's going to happen in the future. But we have to start."

In its previous landmark 19-hour flight from Madrid to Rabat, Solar Impulse demonstrated that energy from the sun was enough to keep the plane in the air, even at night.