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From VOA Learning English, this is the Technology Report.
In 2012, a team of pilots and engineers from Switzerland successfully flew a plane powered by sun light from Spain to Morocco. The same team flew the aircraft across the United States in 2013. Now, the Swiss team is preparing for a flight around the world in 2015. The new, improved version of the plane, named Solar Impulse 2, was recently shown in Switzerland.
Solar Impulse 2 is a very light, single-seat airplane. Its wings are 63 meters across. This large wingspan provides 200 square meters of space for energy cells that charge lithium-ion batteries. These special batteries are needed to keep the plane flying at night.
Four electric motors permit the plane to cruise at a speed of up to 140 kilometers per hour, at an average height of 8,500 meters above sea level. The longest flight of Solar Impulse 1 was made in May 2013. The plane flew from Phoenix, Arizona to Dallas, Texas, a distance of just over 1,500 kilometers.
Pilot Andre Borschberg says Solar Impulse 2 will be able to fly much longer distances between stops.
"When we leave the coast of China, we don't know what the weather looks like on the side of the ocean. So these are big question marks," said Borschberg.
12 years of research and testing went into building Solar Impulse 2. The researchers and testers believe the aircraft will be able to fly around the world in 20 to 25 days and nights.
Andre Borschberg once flew jets for the Swiss Air Force. He says every detail on the airplane is designed to save energy.
"This airplane is an example of energy efficiency, how we save the energy, and how the energy from the sun is enough to keep the airplane in the air day and night," said Borschberg.
Mr. Borschberg will be able to sleep or even exercise when using the autopilot, a flight assistance device.
Bertrand Piccard is the Chairman of the Solar Impulse project. He says the goal of the flight around world is to support energy efficiency.
"It is to bring products to their clients which are more energy efficient: in home buildings, in the transportation, in appliances, it can be lighting," Piccard said.
Solar Impulse 2 begins test flights in May. The flight around the world is planned to start next March from an airport somewhere along the Persian Gulf.
And that's the VOA Learning English Technology Report. For more technology stories go to our website www.hxen.com . I'm Jonathan Evans.
