Photograph courtesy Solar Impulse
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The Solar Impulse 2 is one step closer to completing its solar-powered voyage.

Photograph courtesy Solar Impulse

Solar Impulse Attempts Epic Atlantic Crossing in Trip Around World

The experimental solar plane takes on another challenging leg of its historic journey.

The experimental Solar Impulse 2, a plane powered entirely by the sun, took off from New York City early Monday morning, en route to Seville, Spain. The first-ever attempt to cross the Atlantic using only solar power is expected to take around 90 hours and is one of the tougher legs of the scheduled voyage around the world.

Swiss pilot (and psychiatrist) Bertrand Piccard is at the controls. The flight was previously scheduled to leave Sunday but was pushed back for weather, since the ultra-light craft is highly sensitive to winds.

Piccard is alternating flights with Swiss entrepreneur Andre Borschberg on a total voyage that is expected to cover 22,000 miles (35,000 kilometers) around the world. The plane left Abu Dhabi on March 9, 2015, and is expected to return there later this year. (Learn more about the project.)

Route of the Si2
The completed and planned legs of its around-the-world flight.

The Solar Impulse gets all its energy needs from the 17,000 solar panels lining its top and requires no other fuel. The cells power propellers and charge batteries that are used for flying during the night. (See photos of the journey.)

The plane reached New York on June 11, after a five-hour flight from Lehigh Valley in Pennsylvania. The team has had to take frequent breaks from the various legs of the journey in order to make repairs to the plane, particularly to its batteries.

Several delays have also been caused by unfavorable weather.

During the missions, the pilots must battle exhaustion, because they can only get about three hours of rest per day, broken up into 20-minute sessions while the craft is flown by autopilot.

Yet Piccard says their accomplishments prove that “energy efficiency, solar power, and modern technology can achieve the impossible."

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