The Solar Impulse, an airplane traveling across the United States using only solar power, is in Phoenix today, after reaching Arizona from California Saturday. It took the plane about 20 hours to travel from Mountain View, Calif., near San Francisco.
The aircraft is capable of flying at night as well as in daytime; the plane had about 75 percent of its battery power remaining when it landed in Arizona.
The Solar Impulse's "wingspan is longer than a 747 Boeing, but the entire plane weighs less than a car," as NPR's Steve Henn reported last month.
Comparisons such as that one may brought a moment of humor during Solar Impulse's trip, when the plane's pilot heard the pilot of another aircraft on his radio, asking an air traffic controller why the Impulse required a wide berth.
"Just think of a flying electric car," the controller replied.
The first leg of the trip was piloted by Bertrand Piccard; his co-founder in the venture, André Borschberg, will also pilot the plane during its American trip.
The plane has completed a transcontinental flight before — flying from Switzerland to Morocco last year, as Eyder reported for The Two Way.
With a maximum altitude of nearly 28,000 feet and an average speed of about 40 miles per hour, the Solar Impulse will make three more stops — in Dallas, Saint Louis, and Washington, D.C. — as it crosses the United States. It will then head to New York City.
Along the way, members of the public can visit the plane at airports. Its pilots and crew will also visit local groups to speak about solar-powered flight (details at their website).
Organizers say that after crossing the United States, their next goal is to fly the Solar Impulse around the world.