A solar-powered aeroplane designed to fly day and night without fuel or emissions made its first test flight above the Swiss countryside on Wednesday, making the around-the-world dream of two Swiss adventurers possible.
The Solar Impulse, which has 12,000 solar cells built into its wings, is a prototype for an aircraft intended to fly around the world without fuel from 2012 to promote renewable energy. It glided for 90 minutes above western Switzerland at an altitude of 1,000 metres, with German test pilot Markus Scherdel at the controls.
Piccard, a Swiss psychiatrist turned aviator, is best known for completing the first non-stop, round-the-world flight in a hot-air balloon in March 1999. It took six years to built the carbon fibre aircraft, which has the wingspan of an Airbus A340 (63.4 metres) and weighs as much as a mid-size car (1,600 kilos).
The other main pilot, Swiss engineer Andre Borschberg, has described it as "ten times lighter than the very best glider". "We will continue the test flights, the important thing is to know the exact performance of this aeroplane to be able to improve the design of the second one. It will be the second aeroplane that will fly around the world", Borschberg said after the flight.
Photovoltaic or solar cells supply four electric motors with a maximum output of 10 horsepower each. The plane is ultimately expected to attain an average flying speed of 70 kilometres per hour and reach a maximum altitude of 8,500 metres (27,900 feet). Swiss astronaut and pilot Claude Nicollier, who has flown on NASA missions, is head of test flights. The project's budget is 100 million Swiss francs, 80 million of which has been secured from sponsors, according to spokeswoman Rachel de Bros.