A solar-powered aircraft made history yesterday after flying around the clock on the sun's energy alone, bringing a step closer the dream of perpetual flight.
After 26 hours in the air, the experimental Solar Impulse aircraft with pilot Andre Borschberg onboard made a seamless landing at Payerne airbase in western Switzerland at 9.01 a.m. (0701 GMT), about three hours after daybreak.
"It's the first time ever that a solar airplane has flown through the night," said team chief Bertrand Piccard, the Swiss adventurer who masterminded the project.
"That was the moment that proved the mission was successful, we made it," said Piccard, who achieved the first round-the-world balloon flight in 1999 and whose father and grandfather both broke height and depth records.
Alighting from the single-seater plane with wings the size of an airliner's covered with solar cells, after sitting day and night in the narrow cockpit, Mr Borschberg said that he felt that he was "floating".
"I have the impression that I'm still in the air," the 57-year-old said on the tarmac, as he was showered by congratulations and slaps on the back from the 70-strong team.
"I feel very pleased, really happy. It was a crucial step. Now we'll go even further, we'll do long missions," said Mr Borschberg.
The aircraft had taken off from Payerne at 0451 GMT on Wednesday, for 14 hours of sunshine to power its engines and charge its batteries for the night flight through its array of 12,000 solar cells.
Flight director Claude Nicollier said the flight had exceeded expectations overnight just as Mr Borschberg guided the Solar Impulse towards a landing just after dawn.
"It's a super flight, better than nominal," added Mr Nicollier, a former space shuttle astronaut, yesterday morning.
"We needed also a litle bit of luck, which we had with the weather which was absolutely perfect," he marvelled.
As darkness fell on Wednesday, there were fears that a brief burst of strong high altitude winds had deprived Solar Impulse of some of the stored energy to last the night.
Mr Borschberg seemed unflustered by the 26-hour experience, dismissing "one or two little difficulties".
"The flight was really zen. It's very peaceful, during this time you have the time to think and to concentrate," he explained.
Mr Piccard revealed that Solar Impulse had emerged from darkness with three hours of energy left in its batteries, a far bigger margin than expected.
It was also able to take immediate advantage of a new burst of energy as the sun rose and recharge its batteries by the time it landed.
"Nothing can prevent us from another day and night... and the myth of perpetual flight," an elated Mr Piccard told journalists, as his sights shifted towards the prospect of transatlantic and round the world flights in 2013-2014.
The first prototype, shaped like a giant dragonfly, is clad with solar panels across a wingspan of 63 metres, the size of an Airbus A340 airliner.
The solar cells and nearly half a tonne of batteries provide energy for four small electric motors and propellers - the "power of a scooter", as the crew put it - and weigh little more than a saloon car.
The team is driven by a desire to demonstrate that clean energy and fuel saving is technically feasible and should be developed and used more widely for transport, in the household and at work.
"We didn't really have credibility until today," admitted Mr Piccard. "What we have done today in the air is an example of what should be done on the ground."
However, the venture was looking for partners to help fill a 20 million Swiss franc shortfall in its overall 100 million franc (€75 million) budget, mainly for a new, bigger plane, he revealed.