PAYERNE, Switzerland: A solar powered aircraft was flying in circles high over Switzerland at first light on Thursday, well on its way to completing a historic round the clock flight, the crew said.
Solar Impulse is attempting to make the first such flight on purely solar energy, defying the hours of darkness to keep aloft for more than 24 hours.
Applause and cheers broke out at mission control at Payerne airbase in western Switzerland as dawn broke at 5.43 am (0343 GMT) with the experimental plane still in the air.
“It’s the first time ever that a solar airplane has flown through the night,” said team chief Bertrand Piccard.
The experimental aircraft was likely to land at Payerne at about 8.30 am (0630 GMT).
Flight director Claude Nicollier said at the mission control centre at Payerne airbase that the flight had gone well overnight as pilot Andre Borschberg guided the experimental aircraft towards a landing after dawn.
“It went better than that,” Nicollier said.
The plane emerged from pioneering hours in the night running only on the earlier 14 hour daytime charge its batteries took from its array of 12,000 solar cells on wings the size of an airliner’s.
“It’s a super flight, better than nominal,” added Nicollier, a former space shuttle astronaut.
Nicollier said 57-year-old Borschberg was “very positive” after more than 22 hours in the air in the single seater, having been forced to stay alert for the full period.
“He is in very good spirits physically and mentally,” said Nicollier.
The high-tech single-seater aircraft took off on the historic attempt in the early hours (0451 GMT) of Wednesday.
The controllers decided as darkness fell later in the day to press on with the night flight, despite fears that a sudden burst of strong high altitude wings at dusk had deprived Solar Impulse of some of the stored energy to last the night.
