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"  Electric airplanes are not being made just for joyrides (see &amp;quot;Who&amp;#039;s Killing the Electric Plane?&amp;quot;). Swiss engineers have unveiled the prototype of an airplane they hope will become the first manned vehicle to fly around the world powered only by the sun. The Solar Impulse has the wingspan of a Boeing 747-400 but weighs only 3500 pounds, comparable to a typical family car. The wings are packed with more than 12,000 solar cells that power four 10-hp electric motors and charge lithium-ion polymer batteries. Test flights are expected this year, with a first overnight flight in 2010 and a five-leg world circumnavigation in 2012.           "^^<http://www.w3.org/2001/XMLSchema#string>
<http://www.popularmechanics.com/flight/a4739/4332266/>