Solar Impulse plane soars above Golden Gate Bridge

The Solar Impulse team have already demonstrated that a solar aeroplane can fly during the day and night, but the ultimate aim is to develop a plane that can fly around the world.

However, the next step in the process is to ensure that the plane can fly across America. In preparation for the epic trip, Bertrand Piccard - supported by his team - took the plane out for a test flight over San Francisco Bay in California.

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