Slaps on backs all round for the team behind Solar Impulse, a solar-powered plane which its developers hope will one day fly around the world. On 3 December test pilot Markus Scherdel guided the plane airborne for the first time, flying it along a Swiss runway just a metre off the ground.

“We’ve done it! It actually took off! With its immense wingspan and low speed it seemed to just hang in the air without moving for 30 seconds. But that was enough for it to fly 350 metres,” writes project co-promoter Bertrand Piccard on the team’s blog. Piccard (who will be one of the pilots in Solar Impulse’s planned 2012 world flight) is famous for piloting the first non-stop around-the-world balloon flight in the Breitling Orbiter 3, in 1999.

The plane’s solar panels weren’t actually connected for this maiden flight, or ‘flea hop’, however: instead, its electric motors were powered from onboard batteries. In 2010, the plane will make longer solar test flights. A first non-stop 36 hour flight through darkness is planned in Switzerland some time from next spring (AP).

Nature Materials editor Vicki Cleave examined the mission – and the history of solar planes – in detail in a 2008 feature (see Solar power: A flight to remember, Nature 451, 884-886; subscription required): “Driven solely by energy from the Sun, the plane will be carried aloft by solar cells that generate a total of around 9 kilowatts — roughly the same power available to the Wright Flyer from its single engine … The planned Solar Impulse will have a maximum weight of 2,000 kilograms, including the pilot, almost one-quarter of which will be from batteries for storing energy to fly through the night. If all goes well, the plane will fly at speeds of 50–100 kilometres per hour on its round-the-world trip, landing five times along the way to swap pilots.”

ImageCredit/Solar Impulse