Solar Impulse 2, a plane powered entirely by solar energy, landed at New York City’s JFK Airport late last night, after dramatically circling the Statue of Liberty. The plane, aimed at raising awareness about solar technology as well as pushing its limits, is now more than halfway through its multi-stage, 35,000 km mission to circle the earth using only the power of the sun.
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The landing came after a relatively short jaunt of just five hours, following a takeoff from Lehigh Valley, Pennsylvania. If that seems like a strangely long flight for the distance, it’s because the plane is slow-moving. It’s driven by propellers, and kept aloft by a massive wingspan, rather than the powerful thrust that keeps, say, a passenger jet in the air.
The Solar Impulse 2 took 117 hours and 52 minutes to fly from Japan to Hawaii last year—that’s nearly five days, for those counting, making it the longest solo flight ever. Pilot Andre Borschberg rested during stretches when it was safe for the plane’s autopilot to take over.
The plane’s schedule was thrown off during that trip, though, when damage to its batteries required a nine-month layover for repairs.
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Though Solar Impulse 2 is focused on promoting solar and clean technology, the plane’s endurance has validated a more specific futuristic technology proposal—perpetual flight. Solar planes aloft for weeks or months could provide functions similar to satellites, including both communications and, less sunnily, surveillance.
The next destination for Solar Impulse 2 is Europe, though the specific destination is still open-ended: “Somewhere between Ireland and Morocco,” according to the team. That trip will get going once a clear weather window opens.