Solar Impulse 2 must cross Pacific or risk being stuck in Japan, pilot says

Crew members push Solar Impulse 2 to its take-off position at Nagoya airport. The team says the aircraft faces a long stay in Japan if weather over the Pacific Ocean does not improve soon. Thomas Peter / ReutersShow less

Solar Impulse 2, the solar-powered aircraft attempting to fly around the world, must cross the Pacific within a few weeks or it could be stuck in Japan for a year, said one of its two pilots.

The aircraft, which has been stranded in Japan for three weeks and had to postpone a planned take-off this week because of bad weather over the Pacific, now has only a short window for making the next leg of its journey, said Bertrand Piccard in an interview with the Tribune de Geneve.

By early August, the days will become too short for the solar-driven plane to cross the Pacific, and subsequently the Atlantic Ocean safely, he said. Solar Impulse 2 set off from Abu Dhabi earlier this year in a multi-leg attempt to get all the way around the world without a single drop of fuel.

“Before August 5, we must have crossed the Pacific or the Atlantic,” Mr Piccard said, adding that if the team was unable to do so they would have to find a permanent hangar where the fragile aircraft could pass the winter.

If the plane does make it to the United States, however, it could safely pass the winter there before crossing the Atlantic to complete its round-the-world trip, because the team has a permanent hanger in New York, Mr Piccard said.

His partner, Andre Borschberg, had been scheduled to take off with the plane from the central Japanese city of Nagoya early on Wednesday, bound for Hawaii, on the latest and most ambitious leg of the attempt to circumnavigate the globe using only power from the Sun.

But after a few agonising hours poring over meteorological forecasts covering the five days and five nights the flight was expected to take, mission chiefs pulled the plug.

“There is still a cold front that is blocking our route. Our meteorologists are constantly evaluating alternative routes,” Piccard said.

He pointed out that Solar Impulse 2 can “fly through clouds for 10 hours, but after that it needs blue skies to recharge its batteries. Otherwise, Andre will have to jump out in a parachute.”

“We can’t take that risk,” he said.

The featherweight flying machine was not supposed to land in Japan on its trip around the globe, but bad weather en route from Nanjing, China to Hawaii forced a diversion at the start of June.

Ever since, the crew has been scouring long-range forecasts for an opportunity to restart its record-breaking journey.

Piccard said the many sponsors footing the bill for the project had promised to continue their support, but acknowledged the team would need to figure out how to continue paying salaries to about 150 people working on the venture if it dragged on.