Solar Impulse poised to resume round-the-world flight

Last week, Solar Impulse pilot and co-founder Andre Borschberg confirmed that, as planned, the Solar Impulse 2 (Si2) aircraft is poised and ready to resume its round-the-world attempt in April.

"We had a problem with the batteries, we overheated them," CEO said at the Young Presidents’ Organization EDGE event in Dubai. "The technology works very well – but we decided to change them, not to take any risks, so now we are ready."

The world’s first solar-powered circumnavigation attempt began on March 9 2015 in Abu Dhabi. Si2, piloted by Solar Impulse founder Bertrand Piccard and CEO, and co-founder Borschberg, was expected to complete a five months round-the-world journey over India, Burma, China, the Pacific Ocean, the U.S., the Atlantic, southern Europe and back to Abu Dhabi some time around late July.

Unfortunately, after completing the longest leg of the journey, a record-breaking non-stop solo flight of five days from Japan to Hawaii, the aircraft could not return to the skies. Certain parts of the four 70 liter lithium polymer batteries, attached to the plane’s wings, were damaged due to overheating on that longest leg.

“During the first ascent on day one of the flight from Nagoya to Hawaii, the battery temperature increased too much due to over insulation," the Solar Impulse team explained in the statement.

After the damage proved to be irreversible, the crew postponed the next leg of the round-the-world journey until mid-spring 2016. At the end of the last year the project had raised a further $20 million in funding, adding to the optimism that the aircraft will be able to continue its historic journey.

It is yet undecided where Si2 is landing next time. The destination would depend on weather conditions: “It’s extremely difficult to plan where we’ll be heading for, it can be LA, it can be San Francisco, it can be Phoenix, everything is open," Borschberg said.

Si2’s wings, fuselage and horizontal tailplane are mounted with 17,248 monocrystalline silicon cells, provided by SunPower. The solar cells cover a total area of 250 square meters, delivering a combined power output of 45 kWp. The aircraft is equipped with the power storage, which makes it able to fly at night.