Many Happy Hours in Sunny Skies

Dean Sigler Uncategorized 1 Comment

Eric Raymond, over the last 20 years, has accumulated more solar-powered flying hours than any other pilot. And what hours these have been.

Having met Gunther Rochelt and flown Rochelt’s Musculair human-powered airplane in 1986, Eric was inspired to apply the light construction techniques to the building of a solar-powered airplane.

In 1990, he flew Sunseeker I across the United State in 21 hops totaling 121 hours in the air, going from California to Kitty Hawk, North Carolina, the birthplace of powered flight. He upgraded Sunseeker over the years, improving the powerplant and aerodynamics of the amazingly light aircraft. Even with solar cells, batteries, and a 2.5 kW motor, the airplane weighed little more than a legal ultralight.

Sunseeker II came to have a new wing, a motor twice as powerful as that on Sunseeker I, and improved battery and solar panel controls designed by Alan Cocconi. Eric made several flights in the new craft, one from Ramona, California to the Experimental Soaring Association workshop in Tehachapi, California in 2006.

Sunseeker II

Its construction is light, yet strong, and with improved solar cells, a better motor setup, and a more sophisticated instrument panel, Eric won the best in show award at Friedrichshafen’s Aero Expo 2009, and flew the craft around Europe, including the first solar-powered crossing of the Alps. His slide show (click on the “See our desktop Europe Tour Slideshow” link on the Solar-Flight home page) is a testament to both his flying and photography skills. Despite a threatening overlay of high clouds, Eric achieved one dream on this round of flights – overflying the Matterhorn.

At the end of his continental tour, Eric sailed into Slovenia, home to the Hydrogenius project, and the Znidarsic family. Eric’s latest design, Sunseeker III, will gain the help of Luka Znidarsic, who with his father created the Front-Electric Sustainer motor (See our blog entry, “Power Up Front”, November 1, 2009) in the form of a 20 kW motor, specially designed for the new two seater. He is using wing molds from Icare, the 25-meter solar sailer that wowed Oshkosh over a decade ago, and working with the production facilities of the Stemme works in Switzerland. First flight for the 23-meter craft is scheduled for 2010, with series production planned for 2011. It will also participate in the Berblinger competition in 2011 in Ulm, Germany, where it may compete against Icare’, its wing “donor.” To top off Eric’s very good year, NASA has seen fit to ask Eric to apply for agency support, a goal he has had for over five years.

Sunseeker III

As Bill Moore reported in his EV World interview with Eric in June 2004, “Ever-enamored by his love affair with electric flight, he’s endeavored – without success – to convince NASA officials to fund a conversion of this machine, considered the best motorglider in the world, to solar electric power as a demonstration of what can be done with the technology. Given the advances in solar cells, batteries and electric-drive technologies, not to mention the high cost of fuel, the time may be right, though the funds may have to come from sources other than NASA.” It would seem that even grander advances in motors, batteries, and solar panels (the units on Sunseeker III will be over 22-percent efficient), have made commercial solar flight a near-term possibility. Congratulations to Eric for pursuing that dream for over two decades.

Comments 1

  1. Too bad that NASA doesn’t embrace this kind of solar powered flight. You guys are doing some amazing things, and the A in NASA does stand for aeronautics. It would be nice to couple the genius of a new community with the resources and technical expertise of this nation’s leading institution for flight.

    (Editor’s note: In the interests of full disclosure, Douglas Osheroff is my wife’s brother, professor of Physics at Stanford and co-winner of the 1996 Nobel Prize for his graduate school work with the superfluid characteristics of Helium 3. He was also on the Columbia Accident Investigation Board. I thought he would appreciate Eric Raymond’s photography, since Doug is a superb photographer in his own right.)

Leave a Reply

Your email address will not be published. Required fields are marked *