Solar Impulse 2 Pacific Ocean flight delayed by bad weather

An attempt to cross the Pacific Ocean in a solar-powered plane has been delayed by bad weather.

Swiss pilot André Borschberg was set to depart the Chinese city of Nanjing on Monday evening (GMT) in Solar Impulse 2, but a cold front between China and his destination of Hawaii forced him to remain on the ground, continuing a month-long wait for conditions conducive to a safe crossing.

Battling the weather system could have extended the flight time from five days – which would already smash the previous endurance record for plane flight – to seven.

“This could have been critical for the pilot,” said a spokesperson for the Solar Impulse project, noting that weather forecasts become more uncertain, and the situation more risky, as the flight becomes longer. Borschberg will survive on snatches of sleep, a maximum of 20 minutes at a time, in order to maintain control of the aircraft.

The Solar Impulse 2 carries no fuel and powers its motors with 17,000 solar panels. After a full night’s flight the plane will have lost most of its altitude and be down to 5-10% battery. Each morning Borschberg will have to arrive in clear skies to recharge its bank of batteries.

The weather conditions would have forced Borschberg to “loiter” behind the weather system.

The China to Hawaii flight is one leg on a round-the-world journey expected to take about five months.