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PAYERNE, Switzerland — The Swiss-made airplane built for the first round-the-world solar flight has wings longer than a Boeing 747 jumbo jet yet weighs only about as much as a large car.
The Solar Impulse 2, unveiled to the world Wednesday at Switzerland’s Payerne Air Force Base, is a bigger and better version of the single-seater prototype that first took flight five years ago.
The original plane demonstrated that a solar-powered plane can fly through the night, hop from Europe to Africa and cross the width of the United States.
But its successor needs to be able to stay in the air far longer, because the pilots expect the lumbering aircraft to take at least five days and five nights to cross the Pacific and Atlantic oceans on its journey around the globe next year.
The new version can theoretically stay airborne indefinitely, according to Bertrand Piccard and Andre Borschberg, who founded the Solar Impulse project over a decade ago. Piccard and Borschberg, who will pilot the plane, admit that now they are the weakest link.