With not a drop of fuel, a solar-powered plane completed the first leg of its historic cross-country flight, a 19-hour trip from California to Arizona, touching down at Phoenix's Sky Harbor International Airport on Saturday (May 4) at 4:30 a.m. EDT (1:30 a.m. PDT).
The solar-powered aircraft, named Solar Impulse, had taken off from Moffett Airfield near San Francisco, Calif., at 9:12 a.m. EDT (6:12 a.m. PDT) on Friday (May 3).
Solar Impulse is the first aircraft capable of flying day and night without using any fuel. The plane relies solely on its solar panels and onboard batteries for power. During today's flight, the aircraft is expected to reach a cruising altitude of 21,000 feet (6,400 meters). [Images: Cross-Country Flight in a Solar-Powered Plane]
Piloting the Impulse
Solar Impulse founders Bertrand Piccard and André Borschberg will alternate piloting the single-seater plane over the five legs of the journey. Piccard was at the controls for today's takeoff from California. Piccard took the first leg of the flight.
For Piccard, being able to make the cross-country flight with zero fuel has been a decade-long dream.
"We want to promote the clean technologies that are so important for our world," Piccard told LiveScience from the cockpit of Solar Impulse, as the plane flew over Fresno, Calif., at an altitude of 12,000 feet (3,650 meters). "This is an exciting vision."
In mid-May, the ultra-lightweight plane will begin the second leg of its trip, taking off in Phoenix and landing in Dallas, Texas. Toward the end of May, Solar Impulse will depart for St. Louis, Mo.; the fourth leg will take the plane from St. Louis to Washington, D.C.; and the fifth and last leg will end in New York City in late June or early July.
Each leg of the Solar Impulse expedition will be streamed live, with a video feed that includes information on the airplane's position, altitude and speed, as well as camera views from inside the cockpit and from Solar Impulse's mission control center in Switzerland. [WATCH LIVE: Streaming Video of the Solar Impulse Flight]
Spreading the message
Solar Impulse's cross-country trip is part of an initiative called "Clean Generation," which aims to promote clean technology efforts around the world. The program already has several high-profile backers, including Hollywood director James Cameron, former Apollo astronaut Buzz Aldrin, environmentalist and former U.S. Vice president Al Gore, and British entrepreneur Richard Branson.
The goal, however, is to increase support for the initiative throughout Solar Impulse's coast-to-coast flight. People can sign up on the Solar Impulse website to join the movement, and the names of all supporters are being carried on the plane as virtual passengers on a USB drive.
Piccard hopes to add more and more names to the list at each stopover city on Solar Impulse's cross-country trip.
"When we take off from Phoenix to Dallas, I hope we will have even more people," he said.
While Piccard said the technology is not advanced enough yet for commercial flights in the near future, Solar Impulse's cross-country jaunt demonstrates the enormous potential for using solar technology (and other renewable energy sources) in other aspects of our everyday lives, such as powering office buildings or homes.
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