100 Percent Efficiency? Great! and So What?

Dean Sigler Electric Powerplants, Sustainable Aviation Leave a Comment

A particularly brilliant and demanding manager for whom your editor used to work had a “SO WHAT?” stamp with which he would critique our technical papers and proposals.  His point in defacing our papers was not to be snide, but to force us to defend why we included certain facts – interesting though they may be in themselves. Two different and equally brilliant discoveries by University of Cambridge and University of California, Riverside researchers bring the “so what?” stamp to mind.  Even with their breakthroughs, approaching 100-percent efficient solar cells in the first instance, solar cells may not yet be a perfect fit for aircraft propulsion. Each square foot of the earth’s surface receives about 15 Watts of solar energy during a bright day.  100 square feet of solar cells (about what we could expect for an average-size wing on an average light plane) would see 1.5 kilowatts hitting that surface – not enough to sustain flight on anything but …

Irena Raymond on Flying the Sunseeker Duo

Dean Sigler Electric Powerplants, Sustainable Aviation Leave a Comment

A few days after posting the entry on the Raymond’s first cross country flight in their new solar-powered Sunseeker Duo, your editor received followups from Irena and Eric.  First, Irena shares her impressions of what sounds like a beautiful flight. “Our XC flight with Duo was a great experience. “First of all, because I don’t like too many surprises, I tried to prepare myself as best as possible for this expedition. I was studying the aeronautical chart to get more familiar with the Italian airspace and possible restrictions, looking also at the terrain and possible out landings (just in case. of course). “And then the day of our flight was coming, bringing us a clear, sunny morning. At the noon time, there was not much thermal activity at our area, but far in the mountains we saw towering cumulus. And the GO decision was done. “Everything went smoothly; with the help of the motor we reached first soarable hills. We …

The Raymonds Make the First Two-Passenger Solar-Powered Cross Country Flight

Dean Sigler Electric Powerplants, Sustainable Aviation Leave a Comment

Eric Raymond shared this story of a short cross-country flight between his home field of Voghera, Italy and the town of Pavullo, about 100 air miles away.  It’s significant in being the first cross-country solar-powered flight for two, Eric’s wife Irena sharing flying duties.  The “normal” nature of the trip and the practicality of the airplane show that Eric is expanding his pioneering efforts from his initial flight across the United States in 1990 and his trip across the Alps in 2009 – all on solar power.   He’s received precious little attention in the press for these sublime journeys, a situation we hope to redeem here. “Irena and I just returned from an overnight trip in our new plane, our first experience traveling in it. “We set our goal to be easy, only 100 miles away, and in the conditions we could have flown twice that far, both ways. “Climbing over the clouds on our way, we enjoyed a tailwind …

Sunseeker Duo Goes Dual

Dean Sigler Electric Powerplants, GFC, Sustainable Aviation 1 Comment

Irena Raymond became the first passenger of a solar-powered airplane recently, even taking over control of the Sunseeker Duo she and husband Eric built over the last several years.  Her thoughts provoke awe and envy. “Flying the Duo, skimming the white fluffy clouds from above and playing on the sky, I feel like a bird. No limitations, a pure freedom. It’s so quiet! Compared to a normal airplane, it’s like night and day. You need a very good headset in every other powered airplane, but in this airplane you can speak normally even when the motor is running full power, no headset needed. It is unbelievable.” Eric provides some hard data to complement Irena’s understandably poetic words.  “I am expanding the flight envelope, so far up to 13,000 feet and 85 mph.  My heaviest passenger… is 85 kilograms (187 pounds), and we were able to climb up to 12,500 feet.  80 percent of the solar cells are hooked up.” Responding to …

EAS VIII: Barnaby Wainfan and ESTOL Possibilities

Dean Sigler Electric Powerplants, Sustainable Aviation Leave a Comment

Barnaby Wainfan is an aeronautical engineer with Northrop Grumman and famous for at least two things: his Edison 2, a light car with incredibly low Cd  that won the Progressive Automotive X-Prize in the Mainstream class and his FMX-4 Facetmobile, an airplane that looks like a private pilot’s F-117 and flies stably and safely.  (Video courtesy of Barnaby Wainfan.) Wainfan told the eighth annual Electric Aircraft Symposium audience that short takeoff and landing (STOL) performance is relatively easy, requiring low wing loading and high power.  Efficient (e)STOL is harder. The problem is getting a reasonable cruise speed and good range with the big wing required for short takeoffs and the high drag required for short landings.  He advised his audience to specify the mission, not the aircraft – with the final airplane flowing from the mission. Short takeoff rolls require light wing loading to allow early liftoff at low speeds, and allow best propeller efficiency.  High power allows quick acceleration …

Sunseeker Duo Makes Test Flights from December 17 to Earth Day

Dean Sigler Electric Powerplants, Sustainable Aviation 2 Comments

Eric Raymond announced today that his Sunseeker Duo, the world’s first solar-powered two-seat aircraft, has been making test flights since last December 17, the 111th anniversary of the Wright Brothers’ first flight. The Duo was built by Eric and his wife Irena, and is Eric’s third solar-powered airplane.  His first, Sunseeker I, flew across the United States in 1990, making 21 hops from San Diego, California to Kitty Hawk, North Carolina.  Sunseeker II flew from Friedrichshafen, Germany across the Alps to Italy, then toured around Europe. In Eric’s announcement today, he claims that, “The Duo is the most advanced solar powered airplane in the world and the first that might be suited to production. It is also the first solar powered airplane with a passenger seat.” “Solar Flight’s mission is to lead the way for the future of sport aviation using the most advanced technologies in the world. Irena says, ‘We are working very hard to have the airplane tested …

Your Black Friday (and All-Year) Giving List

Dean Sigler Diesel Powerplants, Electric Powerplants, Sustainable Aviation Leave a Comment

With merchants beating the drums of commerce to lure you to their stores and web sites for holiday cheer (at least for the merchants), your editor has some alternative giving suggestions that could help bankroll the future of aviation (if not aviation futures).  Each of these projects would welcome funding, and each has much to give back to all of us. Put Your Face in Space The Perlan Project has initiated a fund-raising program on Indie-Go-Go, with the immediate goal to complete construction of the major parts of Perlan II, a high-performance, high-altitude research sailplane recently featured in the New York Times.  Its planned mission to 90,000 feet in the Polar Vortex could give us new and profound understanding of global climate change, the ozone hole and greenhouse gases. For a mere $15, you will, “Receive a professionally edited digital video of the entire Perlan Mission II aeronautical exploration, atmospheric science research and record breaking flights.”  For another $14, you …

Solar Impulse Makes It to New York Early

Dean Sigler Electric Powerplants, Sustainable Aviation Leave a Comment

It’s hard to believe that the Solar Impulse has been on its Cross America tour since May 3, but its early touchdown at New York City’s John F. Kennedy International Airport late Saturday night was cause for elation on at least two counts. First, as the Solar Impulse team points out, “For the first time a plane capable of flying day and night powered exclusively by solar energy has crossed the USA from the West to the East Coasts without using a single drop of fuel.”  As we love to point out, though, it’s not the first time a solar-powered airplane has made the trip.  Eric Raymond did it in 21 hops in 1990 in Sunseeker 1, using the technology available at the time – which did not allow overnight flights.  Both trips are literally epic voyages, nonetheless. Second, for several anxious hours the flight, the airplane and even the fate of pilot Andre’ Borschberg, Solar Impulse’s co-founder and CEO, …

Sunseeker Duo Makes Maiden Test Glide

Dean Sigler Electric Powerplants, Sustainable Aviation Leave a Comment

Dr. Seeley shared this video a few hours ago. Eric and Irena Raymond have been crafting their Sunseeker Duo for the last five years, and finally have an airworthy craft, as shown in the video during its maiden flight near Voghera, Italy – new home to the Raymonds. Finishing construction of the world’s first two-seat solar-powered airplane in time for Friedrichshafen’s Aero Expo in April, the pair were honored with pride of place at the international showcase.  “This week we brought the Sunseeker Duo to AERO Friedrichshafen for its public unveiling. The airplane is fresh out of the paint shop, and since it is too large to fully assemble in the Slovenian workshop, it is also the first time that we got to see the airplane in its full glory!” Sunseeker Duo is a 22-meter (72 feet) solar-powered aircraft that weighs a mere 280 kilograms (616 pounds) empty, no more than a typical light sport aircraft.  This is a major …

Solar Flight on a Winter Wave

Dean Sigler Electric Powerplants, Sustainable Aviation Leave a Comment

Eric Raymond sent the following today. “Had a nice SUNSEEKER flight today, 3 hours, and as usual I could have stayed up into the dark, even in January!  This time there was wave lift, but very weak, despite 30 knot winds at 6700 meters (21,500 feet). “In the pictures you can see the inversion clearly, and the Adriatic covered in a blanket of clouds. “My batteries are very old and cold, but I still got high enough to connect with the wave, which went on forever. “Taxing was tricky because of big lumps of snow, so I landed downwind, as the taxiway is not cleared. Both his Solar Flight website News and Blog show more, including the construction of the Sunseeker Duo, the world’s first two-seat solar-powered airplane. One blog entry in particular, shows a flight from Slovenj Gradec to Lesce Bled airport, on its way to Switzerland for an airshow.  He topped Mount Triglav, the highest peak in Slovenia, and …