“A new generation of solar-powered vehicles is making extraordinary journeys around the world and pushing the boundaries of technical knowledge
Tom Cheshire, The Observer, Sunday 25 August 2013
The Solar Impulse glides over the Golden Gate bridge in San Francisco during a test flight in April.
The wings of the experimental aircraft arch more than 63 metres, the same span as an Airbus A340, but they look frail, supported on the airstrip by wheeled struts. They are covered in a patina of 11,268 photovoltaic cells, which look dark blue in the grey predawn. The four 10-horsepower propellers they power now start to spin silently. Bertrand Piccard, a 55-year-old explorer and psychiatrist, dons his helmet and oxygen mask and completes his final checks. The Solar Impulse quietly taxies forwards. The plane is travelling impossibly slowly – 30km an hour – when it gently noses up and leaves the ground. With air beneath them, the rangy wings seem to gain strength; the fuselage that on the ground seemed flimsy becomes elegant, like a crane vaunting in flight. It seems not to fly, though, so much as float. Piccard spends the day wheeling the solar-powered plane around the Matterhorn and lands 12 hours later, after sunset. But the Solar Impulse is a plane that would fly for ever.”