Solar Impulse passes halfway mark to Hawaii
The Swiss solar-powered aircraft flying between Japan and Hawaii as part of a round-the-world bid passed the halfway point of the perilous Pacific Ocean crossing Wednesday, and broke its own endurance record.
Solar Impulse 2 had travelled 55 percent of the way to the tropical US state by 7am GMT, having flown 4,305 kilometres with 3,430 kilometres more to go, according to the project.
By that time the plane and its veteran Swiss pilot André Borschberg had logged 61 hours of continuous flight — easily bettering the previous record of 44 hours they had set between China and Japan.
"Already halfway through what is probably the flight of my life! Loving it!" Borschberg tweeted earlier from the cockpit.
On the third day into the eighth leg of the global circumnavigation, expected to take five days and five nights and billed as the most difficult part of the adventure, the plane crossed a potentially problematic cold front, the project said.
That front — which stretches across the Pacific — is one of the factors that had kept the team stranded in Japan for almost the entire month of June.
"#Si2 crossed the 1st cold front, major hurdle overcome," the team tweeted.
The experimental solar-powered aircraft left Japan around 6pm GMT Sunday — the early hours of Monday local time — after spending a month in the central city of Nagoya.
The propeller-driven plane was originally scheduled to fly directly from Nanjing in China to Hawaii, but bad weather along the way forced a diversion to Japan that stretched to a month.
Borschberg is alone and entirely self-reliant in the 3.8-cubic-metre unpressurised cockpit.
Travelling at altitudes of more than 9,000 metres, he has to use oxygen tanks to breathe and experiences huge swings in temperature throughout the day.
He rests for only 20 minutes at a time and cannot move from his seat, which has a built-in toilet, as well as a parachute and a life raft attached.
Solar Impulse 2 set off from Abu Dhabi earlier this year in a multi-leg attempt to fly around the world without a single drop of fuel.
It has 17,000 solar cells and on-board rechargeable lithium batteries, allowing it to fly through the night.
Its wingspan is longer than that of a jumbo jet but it weighs only 2.3 tonnes — about the same as a car.