Swiss adventurer Bertrand Picard is set to unveil a prototype of the solar-powered plane he hopes eventually to fly around the world.
The initial version, spanning 61m but weighing just 1,500kg, will undergo trials to prove it can fly at night.
Mr Picard, who made history by circling the globe non-stop in a balloon in 1999, says he wants to demonstrate the potential of renewable energies.
He expects to make a crossing of the Atlantic in 2012.
The flight would be a risky endeavour. Only now is solar and battery technology becoming mature enough to sustain flight through the night – and then only in unmanned planes.
But Picard’s Solar Impulse team has invested tremendous energy – and no little money – in trying to find what they believe is a breakthrough design.

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