Flying The Friendly Skies Thanks To Good Old Fashioned Sun Power

Have you ever wondered if an aircraft could be powered exclusively via solar energy? A team of pilots and engineers -- led by Bertrand Piccard (the man who circled the world via hot air balloon back in 1999) and Andre Borschberg -- pondered the very same question before finally putting their outlandish notion to the test. What makes their project especially unique is that it will be the very first manned solar plane to hit the air waves. Although it took them a full four years to develop, the fruit of their fastidious labor is the Solar Impulse HB-SIA aircraft prototype, which was officially unveiled right outside of Zurich on June 26, 2009.

The relatively light 3500 pound composite-material airplane, which can achieve takeoff speeds of up to 22 miles per hour, is equipped with four small electric motors capable of generating an average of 8 - 10 horsepower each. To compensate for such a girly-girl speed, the engineers added a Boeing-747 comparable wingspan of 208 feet and studded each wing with 11,628 solar cells, providing the necessary omph that they were desperately seeking. Props are powered via lithium polymer battery stacks that are attached to each motor, storing an average of 8 horsepower (per stack per day) of solar energy when all is said and done. Couple all of the above with the craft's horizontal stabilizer and you've got one kick-ass 45 mph airplane. Alrighty then.

Fortunately, Piccard and Borschberg have oodles of tests in store for their pet project throughout the upcoming years. They expect to work out many or all of the kinks associated with its relatively subdued speed and the ability of its batteries to sustain overnight trips. On their to-do list is everything from night flights and global circumnavigation in 4 day, 5 stage increments to non-stop flights, culminating in a 2012 world tour which they expect to run from 20 - 25 days. Naturally, they plan to trade off piloting duties. Once they've put the final touches on the Solar Impulse HB-SIA and are happy with its performance, they will then move onto the next generation aircraft in their series, the BH-SIB.