In theory, the carbon-fiber plane will be able to fly indefinitely, fueled by thin solar panels that cover its 236-foot-long wings. The solar power runs four electric motors and charges batteries that allow the plane to keep flying at night. Inside the cockpit, there’s just enough room for the pilot, a bathroom, and a little space to lie down or get some exercise.
The long flight will be challenging for pilots, since the plane flies at just 87 mph. Crossing the Atlantic, for example, will take several days. So the trip will be split into several stages, and the pilots are also training for long flights in a simulator and experimenting with sleeping just two hours a day while using autopilot.
But the plane itself should have no difficulty making the journey. When the Solar Impulse team first started working on the project, aviation experts said that it would be impossible to fly a solar-powered airplane. However, an earlier version of the plane successfully flew across the U.S. last summer, proving early skeptics wrong.
Solar Impulse founder and pilot Bertrand Piccard was undeterred by critics of the project, inspired in part by his grandfather, who broke world records by flying into the stratosphere over 80 years ago. "Specialists were also telling my grandfather in 1931 it was impossible to fly in the stratosphere and he did it," Piccard says. "When you have a project in which everybody believes immediately, it just means that you are not ambitious enough."
The plane isn’t intended to transform into something that can transport passengers, but instead demonstrate what’s possible at the limits of clean tech and renewable energy. "It’s a pioneering project, not an industrial one," Piccard says.
"Protection of the environment is far too often boring and expensive," he adds. "We want to show the opposite. If the technologies of Solar Impulse were used everywhere on a global scale, humankind could divide by two its energy consumption, create new jobs, and make profit in new fields of industry. Let’s be innovative and free ourselves from the old habits and beliefs that prevent us from inventing a better future."