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Solar Impulse plane starts bid to cross US Solar Impulse plane starts bid to cross US
(about 2 hours later)
A plane powered only by the Sun has set off from San Francisco on the first leg of a bid to cross the US with no fuel.A plane powered only by the Sun has set off from San Francisco on the first leg of a bid to cross the US with no fuel.
The Solar Impulse craft will stop in Phoenix, Dallas, St Louis, Washington DC and New York in the coming weeks.The Solar Impulse craft will stop in Phoenix, Dallas, St Louis, Washington DC and New York in the coming weeks.
The team's plane has the same wingspan as an Airbus A340 but weighs only as much as an average car.The team's plane has the same wingspan as an Airbus A340 but weighs only as much as an average car.
It has already made a day-and-night flight lasting more than 26 hours, and the team aims to eventually circumnavigate the globe in 2015.It has already made a day-and-night flight lasting more than 26 hours, and the team aims to eventually circumnavigate the globe in 2015.
The plane took off from Moffett Field on the edge of San Francisco Bay at 06:12 local time (13:12 GMT). It should take about 19 hours to complete the first leg of the American crossing to Phoenix.The plane took off from Moffett Field on the edge of San Francisco Bay at 06:12 local time (13:12 GMT). It should take about 19 hours to complete the first leg of the American crossing to Phoenix.
The craft's wings and stabiliser are covered with nearly 12,000 solar cells, which in daylight hours charge an array of lithium-ion batteries in gondolas that hang below the wing.The craft's wings and stabiliser are covered with nearly 12,000 solar cells, which in daylight hours charge an array of lithium-ion batteries in gondolas that hang below the wing.
Together, these provide power to the plane's four electric motors and allow flight in daylight and night conditions.Together, these provide power to the plane's four electric motors and allow flight in daylight and night conditions.
The HB-SIA craft is being piloted by Bertrand Piccard, a co-founder of the effort, who is perhaps best known for being the first person to circumnavigate the globe in a hot-air balloon, in 1999.The HB-SIA craft is being piloted by Bertrand Piccard, a co-founder of the effort, who is perhaps best known for being the first person to circumnavigate the globe in a hot-air balloon, in 1999.
The trans-America bid is the first attempt of its kind with a zero-fuel aircraft.The trans-America bid is the first attempt of its kind with a zero-fuel aircraft.
Together with co-founder and entrepreneur Andre Borschberg, the pair of Swiss pilots have racked up a number of world records and milestones in recent years.Together with co-founder and entrepreneur Andre Borschberg, the pair of Swiss pilots have racked up a number of world records and milestones in recent years.
The first night flight of a solar-powered craft in 2010 was followed by a first international flight in 2011, and first inter-continental flight in 2012.The first night flight of a solar-powered craft in 2010 was followed by a first international flight in 2011, and first inter-continental flight in 2012.
The two will share the job of flying the plane between each of the stops of the tour.The two will share the job of flying the plane between each of the stops of the tour.
Mr Borschberg said that the atmosphere was "extremely good" ahead of the launch.
"We've peen preparing for this flight since last summer, so we are all very excited," he told BBC News.
The current aircraft HB-SIA is effectively the prototype for the craft that will eventually be used for transoceanic flights and the round-the-world trip. The HB-SIB should be completed by the end of 2013.
"You should see this like being in 1915 when the pioneers were trying to do these first cross-country flights - still unable to cross the ocean, but an important step for the development of aviation," Mr Borschberg said.
The launch on Friday is to serve as the start of the pair's Clean Generation Initiative, an effort to encourage policy-makers and businesses to develop and adopt sustainable energy technologies.The launch on Friday is to serve as the start of the pair's Clean Generation Initiative, an effort to encourage policy-makers and businesses to develop and adopt sustainable energy technologies.
"We want to show that with clean technologies, a passionate team and a far-reaching pioneering vision, one can achieve the impossible," Dr Piccard said at the announcement of the mission in March."We want to show that with clean technologies, a passionate team and a far-reaching pioneering vision, one can achieve the impossible," Dr Piccard said at the announcement of the mission in March.