At last year’s Electric Aircraft Symposium, Ron Gremban, developer of the Prius plug-in hybrid, shared several questions about promoting safety in electric aircraft. One aspect that provoked deep thought was that of safety for those working around an electric airplane, whose propeller could start quietly and possibly strike an unaware bystander. During the Green Flight Challenge, it was noteworthy that unlike their gasoline-powered counterparts which idled while awaiting takeoff, the Pipistrel G4 and e-Genius awaited their turn to launch with propellers at rest, only spinning when commanded – and very quietly at that. The question of avoiding prop strikes found at least one answer at EAS VII. Karl Kaser demonstrated, in model form, his ePropeller Safety Device (eSD), noting “the risk to people, animals or objects in the propeller disk area and that they can be injured or damaged accidentally during the run-up of the propeller.” He first noted that issue in the case of e-Genius, on which he was …
A Smart Battery Management System and Multiple Sensors
Fraunhofer and the Hochschule Esslingen University of Applied Sciences have created an electronic race car that they will show at the Sensor + Test Measurement Fair in Nuremberg, Germany from May 14 through 16. Not only electrically driven, the innovative vehicle holds a number of sensor and control systems that might be of interest to electric aircraft designers. EVE, the product of the school and Fraunhofer’s labors, can sprint from 0 to 100 kilometers an hour (62 mph) in 3.6 seconds with its twin 60 kilowatt, 4,500 rpm motors, and reach a top speed of 140 km/hr (86.8 mph). Its 8 kilowatt-hour lithium polymer batteries allow only a short run of 22 kilometers (13.64 miles) though, not surprising in terms of high power outputs pulling the cells down quickly. Electrical engineering students from the e-racing team at the Hochschule designed the 300 kilogram (660 pound) car as an elective project to augment their studies, and ran it at the International Formula …
Sunseeker Duo Shows Completed Form at Friedrichshafen, Moves to Italy
Erik Raymond is moving his shop and Sunseeker Duo project to Voghera, Italy, nestled in Northern Italy between Milan and Genoa. He showed the completed airframe at this year’s Aero Expo at Friedrichshafen, Germany and discussed, no doubt, the future of electric aviation with Axel Lange, the CEO of Lange Aviation. Lange has developed the Antares and Arcus electric motorgliders, both outstanding designs. Following the Expo’s finale, Erik and his wife Irena drove south to Italy, where their enterprise will complete work on the Duo and plan for their proposed trips in unexplored realms– all on solar power. With Solar Impulse crossing the United States (which Erik did in 1990 in Sunseeker I) and more flights planned by other participants, we might see the next few years create an intensified interest in green aviation. Erik notes that, “The solar cells used by the Duo are better than 50% more efficient than those used by Sunseeker II. While Sunseeker II is …
Solar Impulse Lifts Off on First Leg of Cross America 2013 Tour
With Bertrand Piccard at the controls, Solar Impulse completed its motor runups a few minutes before its scheduled 6:00 a. m. PDT takeoff. The project commentator in Switzerland noted that Piccard looked “a little pensive” in the minutes leading up to the historic departure from Moffett Field in Mountain View, California. The first leg of the trip involves a stepped climb – first to 5,000 feet for about two hours, then to a little over 20,000 feet until about 7:00 p. m. , when the craft will begin a stepped descent for the next several hours and arrive over Phoenix near midnight. As cars whizzed by on the nearby Highway 101 linking San Jose and San Francisco, Solar Impulse’s crew in Payerne, Switzerland called the tower at Moffet to coordinate final departure instructions. After receiving the go-ahead from Payerne, Piccard guided the airplane from the runway at about 6:12 and made an effortless climb into the dawn’s glow over the …
Flying e-Genius for Two Years
At this year’s Electric Aircraft Symposium, Rudolf Voit Nitschmann, Len Schumann, and Ingmar Geiss shared their well-documented experiences with e-Genius, second place winner in 2011’s Green Flight Challenge. Flown by Erik Raymond and Klauss Ohlmann, the airplane managed 397.5 passenger miles per gallon on its 200-mile trek around a closed circuit between Santa Rosa, California and the distant geothermal power plants that provided the electricity for its flight. As Voit Nitschmann, leader of the e-Genius team since 2005 noted, one must design electric aircraft around the beneficial aspects of such vehicles to gain the greatest performance. Originally slated to be hydrogen powered, e-Genius mounts its 59-pound motor on the leading edge of the vertical rudder, more difficult with a heavier internal-combustion engine. This permits ample propeller clearance, provides blade protection and allows a short, retractable landing gear that is light and simple. With no turbulent flow over the nose, the cockpit can be streamlined like that of a sailplane and …
Pipistrel Shares Three New Products and Springs a Surprise
Slovenia, a tiny country which can be seen in its entirety from a light airplane, makes an astonishing array of such vehicles at the Pipistrel factory, awarded a European Union prize as the epitome of green manufacturing facilities. The company uses solar energy to power its operation and reports the number of kilowatts flowing through its plant on its web site. Naturally, we’d expect an environmentally responsible firm to build environmentally responsible products, and Pipistrel is committed to going green. Dr. Gregor Veble, Head of Research in the Research and Development Department; and Tine Tomažič, researcher and designer, shared a multiplicity of new products and gave an all-too-brief glimpse of a surprising future project with participants at the seventh annual Electric Aircraft Symposium at Santa Rosa, California. With over 300 of their two-seat Sinus and Virus aircraft in service, and 50 Taurus G-2 recreational motor gliders surfing the high mountain waves, Pipistrel has a growing customer base, and seems to …
Seventh Annual Electric Aircraft Symposium Unveils New Technology
This year’s CAFE Foundation Electric Aircraft Symposium in Santa Rosa, California had surprises from several sources, including new aircraft, batteries, and materials that will help make the future a good place to be. Some technologies are maturing and some are about to spring forth in ways we won’t see coming. We’ll be looking at each presentation in detail in future postings, but know for certain that the electric aircraft movement is turning a corner as things become integrated in an ever-quicker progression. We will see significant announcements in the next few months. The Symposium included not only technology, but seriously looked at how neighborhoods and society in general can integrate these new technologies in a more responsible way than the current helter-skelter world which pulls us away from family and community. What point is there in having magical things and messy lives?
Solar Impulse Soars Over the Golden Gate
This photograph, by J. Revillard for the Solar Impulse project, speaks well more than a thousand words. It exemplifies the aspirations those of us feel who want to see the skies filled with quiet, efficient aircraft. If the individuals who’ve made this beautiful sight possible want to inspire others, they’ve succeed admirably. Follow the flight of Solar Impulse across America and see more pictures here.
GraphExeter Aims for Power with Transparency
It doesn’t sound much like dispassionate, objective scholarly reporting, but the University of Exeter in England headlines its report on a University-created breakthrough material, “Revolutionary new device joins world of smart electronics.” Layering graphene and the GraphExeter, a material obviously headed for product marketing, gives a “new flexible, transparent, photosensitive device” that can lead to solar-powered clothing able to charge the wearer’s cell phone, “intelligent” windows that can “harvest light and display images,” and just maybe (in this writer’s dreams) help power electric cars and airplanes. GraphExeter, Exeter claims, is the best known room temperature transparent conductor and with graphene – the thinnest conductive material – the pair make for great potential. Researchers developed GraphExeter by sandwiching molecules of ferric chloride in between two layers of graphene. According to the University, “Saverio Russo, Professor of Physics at the University of Exeter said: ‘This new flexible and transparent photosensitive device uses graphene and graphExeter to convert light into electrical signals …
Hey, My Car Needs a Jump Start. May I Borrow Your Cell Phone?
Seriously, think of a battery in your cell phone that could jump start a car, and then be recharged “in the blink of an eye.” That’s exactly what mechanical science and engineering professor William P. King and his team of researchers at the University of Illinois at Urbana-Champaign claim to have created. The most powerful microbatteries ever documented “outpower even the best supercapacitors” and could be in cell phones and small portable devices in the next few years. “This is a whole new way to think about batteries,” King said. “A battery can deliver far more power than anybody ever thought. In recent decades, electronics have gotten small. The thinking parts of computers have gotten small. And the battery has lagged far behind. This is a microtechnology that could change all of that. Now the power source is as high-performance as the rest of it.” Until now, the need for portable power left one with a sharply-delineated choice – to …