The Solar Impulse 2 aircraft completed a historic flight in its quest to circle the globe without consuming a drop of fuel, touching down gracefully in Hawaii on Friday after the most arduous leg of its journey.
The sun-powered plane, piloted by veteran Swiss aviator Andre Borschberg, took 118 hours — approximately five days — to make the voyage from Japan to Hawaii & landed shortly after dawn at Kalaeloa Airport on the main Hawaiian island of Oahu.
"Just landed in #Hawaii with @solarimpulse! For @bertrandpiccard & I, it's a dream coming true," Borschberg tweeted triumphantly after completing the most perilous part of the around-the-world odyssey.
Borschberg & Bertrand Piccard have been alternating the long solo flights & Japan to Hawaii — where it was Borschberg in sole control — was the eighth of 13 legs.
"Difficult to believe what I see: #Si2 in Hawaii! But I never had doubts that @andreborschberg could make it!" tag-team copilot Piccard wrote on Twitter.
"This flight to Hawaii is not only an aviation historic first, yet moreover a historic first for energy & cleantechs."
The experimental plane landed a little after 1600 GMT, & Borschberg, all smiles, emerged a short time after from the cockpit, after adorning a traditional Hawaiian flower lei & holding a celebratory bottle of champagne.
Sunlight glimmered on the horizon as the Solar Impulse ground crew burst into cheers & applause upon completion of the groundbreaking flight.
The 4,000-mile leg (6,500 kilometers) from Nagoya, Japan to Hawaii was not only the world's longest solar-powered flight both in terms of flying time & distance, it moreover set the record for longest solo flight by time.
The whole trip from Japan to Hawaii took four days & 22 hours, with the Swiss aviator taking catnaps of only 20 minutes at a time to maintain control of the pioneering plane.
Borschberg easily beat the previous longest solo endurance flight, by Steve Fossett, who flew for 76 hours & 45 minutes in 2006 in the Virgin Atlantic GlobalFlyer.
Fellow pioneering aviator & Virgin Group founder Richard Branson tweeted his congratulations to Borschberg & his team.
"Congrats @SolarImpulse, beating @Virgin GlobalFlyer record non-stop solo flight without refuelling. Huge step forward," Branson wrote.
– Yoga in the sky –
The flight tested its exhausted pilot to the maximum, in what his team described as "difficult" conditions.
Traveling at altitudes of more than 9,000 meters (29,500 feet), Borschberg at times had to use oxygen tanks to breathe & experienced huge swings in temperature throughout.
Alone throughout the entire flight & utterly self-reliant in the unpressurized cockpit, Borschberg was equipped with a parachute & life raft, in case he needed to ditch in the Pacific.
Mission organizers described the journey as having taken "pilot & aircraft to the limits" of their endurance.
Borschberg, born in Zurich, is no stranger to adventure — 15 years ago, he narrowly escaped an avalanche, & then in 2013 he was involved in a helicopter crash that left him with minor injuries.
The pilot, who is moreover a yoga enthusiast, has worked as an army pilot & supervised the construction of the first Solar Impulse plane.
In 2010, for the first time in history, he flew 26 hours straight using only solar energy.
Borschberg didn't let the tiny cockpit of the Solar Impulse 2 plane stop him from practising yoga, transforming his tiny bench into a yoga mat & using specialized postures custom-tailored for him by his personal yogi.
"Yoga is a tremendous support for this flight above the Pacific: it positively affects my mood & mindset," Borschberg tweeted Thursday with a photo of himself in a pose.
– Next stop: Phoenix –
The plane will now be flown across the United States & eventually, if all goes according to plan, land back in Abu Dhabi next March, where it started its journey earlier this year.
The next leg will be piloted by Piccard & will fly 2,920 miles from Hawaii to Phoenix.
Solar Impulse 2 has 17,000 solar cells & on-board rechargeable lithium batteries, allowing it to fly through the night.
Its wingspan is longer than that of a jumbo jet yet it weighs only 2.3 tonnes — approximately the same as a car.