Impulse flight

The first solar aircraft aiming to fly night and day without fuel will be unveiled in Switzerland on 26 June.

The prototype aircraft, called the HB-SIA, has been developed through Solar Impulse, a project run by Swiss aviators Bertrand Piccard and André Borschberg.

The aircraft, which has been under construction since 2007, combines a lightweight 1,500kg structure with a 61m wingspan and a length resembling that of an Airbus 340. The difference is these wings are covered in a thin sheet of solar cells that convert the sun’s rays into electricity that drives the machine’s engines.

The Solar Impulse team hopes its aircraft will make its first test flight in October of this year. If all goes according to plan, it could make a 36-hour flight in 2010 without fuel.

The team also hope to build another aircraft to fly several consecutive 24-hour cycles. This will lead to the first transatlantic flight in 2012 and then an around-the-world flight.