Two New Electric Sailplanes

Dean Sigler Batteries, Electric Aircraft Components, Electric Aircraft Materials, Electric Powerplants, Sustainable Aviation 6 Comments

Two electric sailplanes come from different ends of the soaring spectrum and each shows its own unique character.  Their differences are as noteworthy as their geographic separation. Birdy Birdy is a single-seat, electrically powered motor glider that fits the European Union 120 kilogram class.  The 264-pound empty weight puts it 10 pounds above America’s FAA Part 103 254-pound limit.  But Euro craft in that category are not as limited in top or cruise speed. Birdy’s light weight required clever arrangement of components to enable a maximum takeoff weight of 280 kilograms (616 pounds) and pilots up to 1.95 meters (6’ 5”) tall.  Its 13.5-meter (44.29-foot) wingspan carries only 13.9 pounds per foot, enabling 40:1 glide ratio at around 90 kilometers per hour (55.8 mph).  Its 8.3 square meter (89.3 square foot) wing area lifts only 6.89 pounds per square foot, enabling a 63 km/hr (39 mph) stall speed with flaps.  Birdy can top out at 180 km/hr (111.6 mph), well …

A 24-Volt Airplane Motor?

Dean Sigler Batteries, Biofuels, Electric Powerplants, Hybrid Aircraft, Sustainable Aviation 2 Comments

One of the big surprises in last month’s webinar hosted by the EAA and presented by Brian Carpenter of Rainbow Aviation Services/Adventure Aviation was the 24-Volt motor being developed for the EMG-6 ultralight motorglider. High and Low Voltages Many, if not most of the electric motors flying on existing craft are higher voltage units.  For sake of an off-handed definition, we’ll divide low and high at below and above 50 Volts, something OSHA delineates in its regulation 29 CFR 1910.303(g)(2)(i), which “generally requires “’live parts of electric equipment operating at 50 volts or more’ to be ‘guarded against accidental contact by use of approved cabinets or other forms of approved enclosures’ or by other specified means.”  In its explanation, the Occupational Safety and Health Administration “considers all voltages of 50 volts or above to be hazardous. Electric current, not voltage, passing through the human body causes injury….” And it really doesn’t take much amperage to take a person to the …

NASA Tests Pipistrel Systems To Aid Electric X-plane Program

Dean Sigler Electric Aircraft Components, Electric Powerplants, GFC, Hybrid Aircraft, Sustainable Aviation Leave a Comment

Taja Boscarol of Pipistrel in Slovenia relays the information that NASA has tested Pipistrel’s electric propulsion system as part of its electric flight research for the X-57 program.  It would seem reasonable to start by checking out Pipistrel’s well-tested motor package, one of the few that comes with fully-matched controller, batteries, and ancillary gear. NASA performed its tests on its 13.5-foot Airvolt stand at the Armstrong Flight Research Center at Edwards Air Force Base, California.  Heavily instrumented, the Airvolt stand collects data through “high-fidelity sensors,” and transmits the collected information to a data acquisition unit that processes, records, and filters the measurements.  NASA and Pipistrel should be able to make good use of this data. Normally installed on the Taurus Electro G2 motorglider, the Roman Susnik designed motor produces 40 kilowatts (53.6 hp.) at low rpm while producing high torque, an ideal combination for rapid climbs to soaring altitude. NASA will collect “torque and thrust measurements, high-fidelity voltage analysis, power …

Siemens Makes a Big, Light Motor

Dean Sigler Electric Powerplants, Sustainable Aviation 2 Comments

Its 14 kilogram (30.8 pound), 85 kilowatt (114 horsepower) motor already graces the nose of the PIpistrel WattsUp, and Siemens seems to have expanded its aeronautical offerings with its new 50 kilogram (110 pound), 260 kilowatt (348.5 hp.) unit.  According to Dr. Frank Anton, Head of eAircraft at Siemens Corporate Technology, the new motor “make[s] it possible to build series hybrid-electric aircraft with four or more seats.” Siemens claims a world record of five kilowatts per kilogram, although Roman Susnik, with his Emrax motors pulling close to 10 kilowatts per kilogram, might contest that, and LaunchPoint is working toward eclipsing that mark.  To be fair, it’s certainly a giant boost over the power-to-weight ratio of most industrial-type electric motors, which Siemens also produces in large numbers. The company, according to its press release, intends to start flight testing the new motor before the end of this year, and hopes to increase output even more. In 2013, Siemens partnered with Airbus …

Eurosport Exploring New Configurations

Dean Sigler Electric Powerplants, Sustainable Aviation Leave a Comment

Unhappily, we missed seeing Tom Leite at this year’s Electric Aircraft Symposium. Happily, he was at Eurosport Aircraft, his company in Portugal, working on innovative new approaches to making electric and hybrid motor-gliding a reality. He also has a speedster that would give those who desire rapid transit a high-style alternative. As shown in the video from Aero Friedrichshafen, the Crossover will probably trend toward a simpler wing configuration, with a fixed span of 18 meters (59 feet) and flaperons that will replace the multiple flaps on the current short-span version being flown in test flights. It’s uncertain whether the current twin-motors that pop out of the sides of the extremely slender fuselage will be retained, but a new version of the Crossover will feature three power options. As shown at Aero 2014, the airplane has the two options outlined on opposite sides of the fuselage – the port side displaying the Rotax-powered version, with a carbon-fiber shaft transmitting power …

June is a Happy Month for Electric Motorsports

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

With only half the month gone and the Pikes Peak International Hill Climb scheduled on its last week, June 2014 has seen records crumble at the Isle of Man TT and hybrid electrical technology dominate at the 80th running of the 24 Hours of Le Mans. The electric part of the classic road race on the tight little island between Britain and Northern Ireland saw new records for the 37 mile spin around the southern roadways – like the Le Man circuit, otherwise public roads usually dominated by farm vehicles and passenger cars. Ohio State University’s Buckeye Racing Team ran a modified Honda CBR1000RR frame with a motor by Roman Susnik, the Slovenian who also designed the motors used in the Pipistrel G2 self-launching motorglider.  They ran a respectable third place, a great accomplishment for a college team up against the might of the winning Honda Mugen.  John McGuinness rode that $4.3 million racer to set a lap record of …

Sunseeker III Becomes the Duo

Dean Sigler Electric Powerplants, Sustainable Aviation Leave a Comment

Dropping a digit and its Latinate numeration, the recently renamed Sunseeker, a joint collaboration between Eric Raymond and a group of German, Swiss, Polish and Slovenian contributors, is showing progress towards its 2011 test flights. The 23-meter (75.46 feet) span solar-powered sailplane takes its wing from the Stuttgart Akaflieg Icare II, its fuselage from the Stemme basic profiles, is being built at least partially in Poland, and uses an electric motor designed by Slovenian native Roman Susnik, as noted in an earlier entry. The craft’s specifications provide evidence of the care employed in the design and construction of this lightweight marvel.  A 75-foot wing aircraft weighing 270 kilograms (594 pounds) empty and 470 kilograms ( 1,034 pounds) when carrying two in its side-by-side cockpit is an achievement.  Compare that to the 345 kg (765 pounds) empty weight and 550 kg (1,220 pounds) maximum weight of a “light” Piper Cub, with only a 36-foot, strut-braced wing.    The 13.8 pounds-per-foot span loading (compare to the Cub’s 33.9 pounds-per …

Solar Sailer Seeks Companionship

Dean Sigler Electric Powerplants, Sustainable Aviation Leave a Comment

Until now, all solar flight has been solo.  This is understandable, given the need for light weight and large wing areas.  But Eric Raymond is about to change this with Sunseeker III, the world’s first two-seat solar-powered airplane, shown at last weekend’s Green Aviation Show at Le Bourget Field near Paris, France.  Indoor displays were in the Musee’ de l’Air et de L’Espace (the Air and Space Museum). Sunseeker III has a roomy side-by-side seating arrangement in a fuselage derived from the Stemme sailplane.  The wing is crafted from the molds (on long-term loan) for Stuttgart University’s 25-meter (80 feet) Icare II, flown in 1996.  As Raymond explains in his blog, “Professor Nitschmann’s design firm www.sfl-gmbh.de is very friendly to our project, and we hope to work together in the future on solar powered aircraft.”   The 20 kilowatt motor is being developed by Slovenian Roman Susnik, and fabrication of the wings is taking place in Slovenia, making the effort a virtual European Union assemblage. In his blog, Raymond …