Tensions were running high in the team as an AFP reporter watched the high tech prototype lift into blue skies at a speed of just 45 kmph after a one kilometre run down the runway at Payerne air base.

Propelled by four 10 horsepower electric motors, the gangling single-seater aircraft and test pilot Markus Scherdel slowly gained altitude for a scheduled flight of around two hours at an altitude of around 1,000 metres (3,280 feet).

The prototype, which is slightly smaller than the plane that will undertake the round-the-world flight, has a wingspan comparable to that of an Airbus A340 airliner but weighs as little as a family-sized car at only 1,600 kg (3,527 pounds).Andre Borschberg, co-founder of the project, along with pioneering round-the-world balloonist Bertrand Piccard, said the first flight was primarily aimed at testing the complex aircraft’s behaviour in the air.

“It’s a very important moment after seven years of work,” he told journalists shortly before take off, adding that the team was “prepared, but facing the unknown.”