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Solar Impulse plane starts bid to cross US Solar Impulse plane lands in Phoenix
(1 day 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 completed the first leg of a journey that aims to cross the US.
The Solar Impulse craft will stop in Phoenix, Dallas, St Louis, Washington DC and New York in the coming weeks. Solar Impulse, as the vehicle is known, took off at dawn from San Francisco, California, on Friday and landed in Phoenix, Arizona, some 18 hours later.
The team's plane has the same wingspan as an Airbus A340 but weighs only as much as an average car. The craft will stop over in Dallas, St Louis, Washington DC and New York in the coming weeks.
The plane has the same wingspan as an Airbus A340 but it weighs just 1.6 tonnes.
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) on Friday, and landed at Phoenix's Sky Harbor Airport at 00:30 local time (07:30 GMT) on Saturday.
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. This meant Solar Impulse spent several hours flying in darkness, relying solely on the energy stored in an array of lithium-ion batteries to drive its propellers.
Together, these provide power to the plane's four electric motors and allow flight in daylight and night conditions. In daylight hours, these are charged by nearly 12,000 solar cells that cover the craft's wings and stabiliser.
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 was 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 been preparing for this flight since last summer, so we are all very excited," Mr Borschberg told BBC News.
"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.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."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 served 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.