In 1911, the first airplane to fly across the United States completed the more than 4,000-mile journey over 49 days, in 82 hours flying time, at an average speed of 51.5 miles per hour. It was an extraordinary aviation milestone in its day. Just eight years after the Wright brothers inaugurated the aerial age with their historic first flights at Kitty Hawk, Calbraith Perry Rodgers, also flying a Wright airplane, demonstrated the feasibility of crossing the country by air. Fast-forward 102 years and a century’s worth of aviation progress and we are heralding another US trans-continental flight. An unusual looking, four-engine, single-place, 200-foot wingspan airplane called Solar Impulse is making the same journey the pioneering Cal Rodgers did in 1911. Solar Impulse flies at a little less than 50 miles per hour average speed and is covering the 4,000 miles over about two months in a little more than 80 hours flying time. Wait a minute. Less than 50 miles per hour, over two months, in 80 hours flying time? Doesn’t sound like progress, does it? Why are we pointing to Solar Impulse as a significant aviation achievement? Here’s why. On the flight across America, Solar Impulse does not consume a single drop of fuel!

As the name implies, Solar Impulse’s four electric motors run entirely on solar energy. The airplane is an extraordinary engineering accomplishment. It can take off in the morning, fully charge its batteries in just a few hours by the solar cells in the wings, and store enough energy to fly all night. It is a totally self-sustaining, clean energy, environmentally friendly aircraft. Solar Impulse won’t be setting any new speed marks or carry any payload or passengers. But that’s not what pilots Bertrand Piccard and André Borschberg, and the Solar Impulse team, are after. They are not out to break any traditional aviation performance records. Their goals are much more visionary. They want to take aviation in an entirely new direction, and show the potential of solar energy.

As has so often been the case since the Wright brothers first flew, path breaking achievements in aviation have influenced the world well beyond flight technology. In numerous ways, the world we live in was shaped and defined by progress in aerospace. Everything from the composition of our material world, to the commerce of our economic system, to the social and cultural dimensions of globalization, to the philosophical contemplation of our place in the universe, has been influenced by developments related to flight technology. The Solar Impulse team seeks to take their place among the trail blazers who have done more than achieve another aviation milestone. They wish to be pioneers in shaping a world where solar energy has a profound role in the way we live. At the beginning of the first aviation century, when Cal Rodgers rolled the wheels of his Wright airplane into the surf of the Pacific Ocean at the end of his transcontinental journey, many sought to envision where aviation would take us. Today, in the second decade of the second aviation century, we are asking the same questions. What will the next hundred years of human flight bring? In the year 2113, how will we be flying and what broader applications of flight technology will be influencing our daily lives? It may be hard at this moment to see the long-term influence of Solar Impulse. But in 1911, when Rodgers made the first flight across America, it wasn’t so clear that in a hundred years we would be routinely jetting back and forth from coast to coast in just a few hours. Maybe, decades from now, if solar energy technology becomes a prominent component of human sustainability, we’ll recall the name Solar Impulse and say, those people had pioneering vision and helped to build the future. I think Cal would agree, even if his airplane did fly faster.

In this video, Peter Jakab talks with pilots Bertrand Piccard and André Borschberg about Solar Impulse's place in aviation history: