The world's most advanced solar-powered plane successfully carried out its latest test flight on Tuesday, soaring at 3,000 feet above the Bay Area of California and the iconic Golden Gate Bridge.
The Solar Impulse, which weighs only about 3,500 pounds, runs completely on power from the sun drawn from 12,000 solar cells that send energy into batteries that power propellers running on four electric motors.
Tuesday's flight was a technical test run to prepare for a planned cross-country trip beginning in early May.
Scroll down for video
The world's most advanced sun-powered plane flies over the Golden Gate Bridge while doing maneuvers in Marin County, California
Tuesday's flight was a technical test run to prepare for a planned cross-country trip beginning in early May
On the first leg of the trip, the plane will depart from the Bay Area and head to Phoenix, said Alexandra Gindroz, spokeswoman for the Swiss firm Solar Impulse, which owns the plane.
But the test run is also about something more.
‘For us, it's really a message to fly over the Golden Gate Bridge and the Bay Area,’ she told KTVU.com. ‘It means that we are here and it's a landmark.’
More...
Epic adventures: National Geographic showcases breathtaking images taken around the world by photographers vying to win 2013 Traveler Photo Contest
Fish and ducks swim by office windows in flooded Midwest as river swells could worsen with continued rain
Dramatic moment a massive boulder that blocked bridge after being dislodged by earthquake is removed with a huge explosion
The plane was created by pilot Andre Borschberg in Payerne, Switzerland, and the flight path will take it to Dallas, Atlanta and finally to New York in early July.
The plane reaches a top speed of 43 mph and holds the record for altitude for solar-powered planes at 30,300 feet, according to the company's website.
Solar Impulse is planning an even longer around-the-globe flight in 2015.
The Solar Impulse cross-country electric aircraft flies over the Golden Gate Bridge while doing maneuvers on Tuesday afternoon
The lightweight plane, which has a wingspan of 208 feet, flew at about 3,000 feet in the air during Tuesday's test flight
The delicate, single-seat plane cruises around 40 mph and can't fly through clouds
This was the plane's second test flight in the U.S. following a two-hour practice run in the same area last Friday.
‘That's a mythical step in aviation,’ André Borschberg, one of the plane's pilots and creators, said about flying cross-country. ‘We are something like between 1915 and 1920, compared to traditional aviation, when pioneers tried these non-stop flights.’
The Solar Impulse is powered by about 12,000 photovoltaic cells that cover massive wings and charge its batteries, allowing it to fly day and night without jet fuel.
It has the wing span of a commercial airplane but the weight of the average family car, making it vulnerable to bad weather.
Its creators say the Solar Impulse is designed to showcase the potential of solar power and will never replace fuel-powered commercial flights.
Safe landing: The Solar Impulse is seen after landing from its test flight at Moffett Field NASA Ames Research Center
The Solar Impulse is wheeled into a hangar after its test flight
The delicate, single-seat plane cruises around 40 mph and can't fly through clouds.
Borschberg and Bertrand Piccard, Solar Impulse co-founder and chairman, said the plane should be ready for the cross-country journey on May 1, depending on the weather.
‘We like nice weather. We like sunny days,’ Borschberg said.
Stops are planned in Phoenix, Dallas, Washington, D.C., and New York. Each flight leg will take 20 to 25 hours, with 10-day stops in each city.
Between Dallas and Washington, the plane will also stop at one of three other cities - Atlanta, Nashville or St. Louis.
Borschberg said the plane's creators are close to being able to launch the non-stop flights needed to go around the world.
Using solar power, ‘we are close to the notion of perpetual flight,’ he said.
The Solar Impulse has already made international and intercontinental flights in Europe and Africa.
Solar Impulse Across America 2013
Impressive feat: Considered the world's most advanced sun-powered plane, the Solar Impulse took off from Moffett Field in Mountain V