Recently,a solar powered plane took to the sky for the first time. It had passed an important test on the way to travel around the world. The plane took off from an airport in Switzerland at 45km an hour. It slowly rose above the fields and into the sky. "There has never been an airplane of that kind that could fly -- never an airplane so big, so light, using so little energy," said Bertrand Piccard, a leader of the project. During the 90-minute flight, the plane did several turns. It climbed nearly 1.6km above the countryside. Engineers plan to test a night flight before July. Then they will use the results of the tests to build a second plane. They plan to travel around the world in that plane in 2012. The plane flies at 70 km an hour. That is faster than a bike and slower than a car. Piccard and pilot Andre Borschberg will take the plane around the world. The pilots will keep the plane in the air for up to five days at a time. "We want to fly it day and night with no fuel  ," Piccard said How long did the first flight of the solar powered plane last?
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