Solar Impulse completes first leg

The solar-powered plane flew from San Francisco to Phoenix to complete the first leg of its trip. The trip is an attempt to fly across the United States with no fuel but the sun's energy and the plane can even fly at night. It has the wingspan of a 747 jumbo jet, weight about the same as some compact cars and only has room for one pilot.

Solar Plane Takes Off on Last Leg of Historic Cross-Country Flight

Solar Impulse flies over the runway at Moffett Airfield in California shortly after takeoff on May 3, 2013.

Experimental Solar Powered Plane Takes Test Flight

MOUNTAIN VIEW, CA - MAY 03: Pilot Bertrand Piccard takes off in the Solar Impulse solar electric airplane at Moffett Field on May 3, 2013 in Mountain View, California. Pilots Bertrand Piccard and Andre Borschberg are attempting the first cross-continental flight in a solar powered plane that can travel day and night. (Photo by Beck Diefenbach/Getty Images)

Experimental Solar Powered Plane Takes Test Flight

MOUNTAIN VIEW, CA - MAY 03: Pilot Bertrand Piccard runs tests before he took off in the Solar Impulse solar electric airplane at Moffett Field on May 3, 2013 in Mountain View, California. Pilots Bertrand Piccard and Andre Borschberg are attempting the first cross-continental flight in a solar powered plane that can travel day and night. (Photo by Beck Diefenbach/Getty Images)

Experimental Solar Powered Plane Takes Test Flight

MOUNTAIN VIEW, CA - MAY 03: Pilot Bertrand Piccard (R) shakes hands with pilot Andre Borschberg before Piccard takes off in the Solar Impulse solar electric airplane at Moffett Field May 3, 2013 in Mountain View, California. Pilots Bertrand Piccard and Andre Borschberg are attempting the first cross-continental flight in a solar powered plane that can travel day and night. (Photo by Beck Diefenbach/Getty Images)

Experimental Solar Powered Plane Takes Test Flight

MOUNTAIN VIEW, CA - MAY 03: Pilot Bertrand Piccard waves goodbye before taking off in the Solar Impulse solar electric airplane at Moffett Field on May 3, 2013 in Mountain View, California. Pilots Bertrand Piccard and Andre Borschberg are attempting the first cross-continental flight in a solar powered plane that can travel day and night. (Photo by Beck Diefenbach/Getty Images)

Experimental Solar Powered Plane Takes Test Flight

MOUNTAIN VIEW, CA - MAY 03: The Solar Impulse solar electric airplane sits on on the runway at Moffett Field before flying to Pheonix, Arizona, as part of a cross-country trip May 3, 2013 in Mountain View, California. Pilots Bertrand Piccard and Andre Borschberg are attempting the first cross-continental flight in a solar powered plane that can travel day and night. (Photo by Beck Diefenbach/Getty Images)

Solar-Powered Plane Set to Begin Historic Cross-Country Flight Friday

The pilots and crew of Solar Impulse before a flight.