A solar-powered aircraft that flies without jet fuel began its attempt at a flight across the United States on Friday.
(Test flight from Moffett Field_Solar Impulse flies over the Golden Gate bridge. Photo, courtesy of Solar Impulse.)
Solar Impulse, the solar powered aircraft developed by Swiss pilots Bertrand Piccard and Andr Borschberg, is a single-seater plane powered by 12,000 solar cells that rest below the solar panels on the upper part of the wings. The cells capture the energy of the sun and transform it into electricity, simultaneously powering the aircraft's four engines and lithium ion batteries.
Piccard began the first leg of the flight from San Francisco to Phoenix on Friday morning, departing from Moffett Field, a joint civil-military airport. The flight is expected to last 15 to 20 hours, reaching a cruising altitude of 21,000 feet. Piccard and Borschberg will alternate piloting the plane, with stops in Dallas; St. Louis, Mo.; and Washington, before completing the journey at John F. Kennedy International Airport in New York.
The team is tracking the flight live on its website, with updates on its position.
While Piccard and Borschberg do not foresee solar power becoming a source for power on commercial aircraft, their "Clean Generation" initiative seeks to "encourage governments, businesses and decision-makers to push for the adoption of clean technologies and sustainable energy solutions."
Solar Impulse completed a 26-hour flight in 2010, and a flight from Switzerland to Morocco in 2012. After the cross-country flight, the team plans on using the plane to circumnavigate the globe in 2015.
Related: Solar Impulse Ready for Coast-to-Coast Flight