The world’s first round-the-world trip on a solar-powered plane got under way Monday with the initial leg from Abu Dhabi to the Omani capital, Muscat.

Swiss pilots Bertrand Piccard and André Borschberg will pursue a record-shattering five-month journey, spanning 21,750 miles across several continents and two oceans, while using zero conventional fuel.

The Solar Impulse-2’s lightweight construction — weighing a mere 4,600 lb. — combined with its 236-ft. wingspan lined with 17,000 solar cells, makes it the first solar-powered aircraft capable of flying during both day and night.

“I am confident we have a very special airplane, and it will have to be to get us across the big oceans,” Borschberg told the BBC.

The pilots have undergone rigorous preparation drills, and will forgo all sleep longer than 20 minutes while airborne, practicing yoga and self-hypnosis to cope with their airborne ordeal. (Some stints will involve flying continuously for five days.) Rest stops will be spent advocating for their clean-technology campaign.

“I had this dream 16 years ago of flying around the world without fuel, just on solar power,” said Piccard. “Now we’re about to do it.”

[BBC]

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