Solar Impulse arrives at its home base in Payerne, Switzerland, July 24, 2012. The world's biggest solar powered aircraft, Solar Impulse, on Tuesday touched down at its home base in Payerne, Switzerland, crossing the finish-line for its fuel-free intercontinental voyage. Photo: Xinhua
Pilot Bertrand Piccard (L) and project initiator Andrew Borschberg waves after Solar Impulse arrived at its home base in Payerne, Switzerland, July 24, 2012. The world's biggest solar powered aircraft, Solar Impulse, on Tuesday touched down at its home base in Payerne, Switzerland, crossing the finish-line for its fuel-free intercontinental voyage. Photo: Xinhua
Solar Impulse arrives at its home base in Payerne, Switzerland, July 24, 2012. The world's biggest solar powered aircraft, Solar Impulse, on Tuesday touched down at its home base in Payerne, Switzerland, crossing the finish-line for its fuel-free intercontinental voyage. Photo: Xinhua