ROUGH CUT (NO REPORTER NARRATION)
The solar-powered plane called Solar Impulse landed at Washington Dulles International Airport on Sunday (June 16) completing the fourth and second-to-last leg of it's cross-country flight powered only by the sun.
Solar Impulse took off from St. Louis and after a 14-hour stopover in Cincinnati landed in Dulles at 12:15 a.m.EDT (0415gmt)
The brainchild of Swiss pilots Bertrand Piccard and André Borschberg, Solar Impulse flies at an average pace of just 43 miles per hour (69 km per hour). Both co-founders take turns flying the plane, which has a single-seat cockpit. It began its cross-country sojourn on May 3 with an 18-hour-plus flight from northern California to Phoenix.
With the wingspan of a jumbo jet and the same weight as a small car, the Solar Impulse is a test model for a more advanced aircraft the team plans to build to circumnavigate the globe in 2015.
The aircraft runs on about the same power as a motor scooter, p
