Solar Impulse sets off on its journey across the US

Early this morning at Moffet Air Field in Mountain View, California, Solar Impulse finally took off on the first leg of its barnstorming tour across the US. Of course, this isn't the first time the sun-powered plane and its pilots, Bertrand Piccard and Andre Borschberg, have flown long distance, but it is the first time it's taken wing through American airspace. Why has it come across the pond? To raise pubilc and political awareness about the benefits of going green and increasing energy efficiency -- and perhaps pick up an additional sponsor or two for its second-gen aircraft (currently in development) meant to fly around the world in 2015. "With the technologies we have onboard, we can divide by two the energy consumption of our world, and produce half of the rest [energy we need] with renewable sources" according to Piccard.

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Solar Impulse Across America

This first portion of the journey will end in Phoenix, and it'll take around twenty hours to get there, as the plane's meager output limits its average speed to around 40MPH. Should any of you want to join along with Piccard and Borschberg as they fly across the country, you can hit the Solar Impulse Across America website to see a livestream from the cockpit, along with real-time altitude, air speed and battery status of the aircraft. And, you can watch a video of Solar Impulse taking off on its North American journey and hear Borschberg talk about learning to fly it after the break.