Experimenter is a magazine created by EAA for people who build airplanes. We will report on amateur-built aircraft as well as ultralights and other light aircraft.
Issue link: http://experimenter.epubxp.com/i/401344
36 Vol.3 No.10 / October 2014 UNDER THE COWL are still only marginally useful as the batteries are expensive and operating times are still short. Just as with computer tech- nology, buyers are putting of a buying decision as they know battery technology is advancing rapidly; perhaps the "next" bat- tery generation is going to be the right one. Europe is progressing much faster in this fi eld. At AERO Friedrichshafen 2014, we saw a nice choice of electric aircraft, including the E-Volo helicopter, the GreenWing International single-seat eSpyder, and the Pipistrel two-seat glider, which is in regular production in Slovenia. As of August 22, 2014, there is another shooting star in this fi eld, the Pipistrel WATTsUP. This new two-seat, all-electric trainer is powered by an 85-kilowatt electric motor (weighing 14 kilograms/34 pounds) and in conjunction with the 17-kilo- watt battery pack, it's capable of one-hour operation plus 30 minutes reserve. In Europe, the price of fuel is putting much greater pres- sure on aircraft developers to electric aircraft. Even Airbus intends to bring out a two-seat e-Fan and then the four-seat version. Stay tuned; we will soon fl y this e-Fan and will report about several other interesting projects that are still consid- ered as "classifi ed." At AirVenture 2014, Mark Beierle of Earthstar Aircraft was fl ying a Joby Energy Inc. motor with 20-kilowatt output that he helped develop. It's powered by two 2.8-kilowatts/hour lithium-polymer batteries from Zero Motorcycles. Those bat- teries have an endurance of up to 40 minutes, although using a larger 11.4-kilowatts/hour battery would allow the aircraft to stay airborne for 70 minutes. An onboard charger allows the batteries to recharge in seven hours, but a larger ground unit can give a one-hour turnaround. Beierle said that electric aircraft are now viable for sport aviation, given that a recent survey of ultralight pilots showed their average flights were only 40 minutes, with a minority claiming they want to stay much longer airborne. For more information, visit www.ThunderGull.com . Also during AirVenture 2014, we had the opportunity to talk to Dan Lineback, owner of the Florida-based ICE Motor, who displayed an unusual variable electric motor. The actual specifications, cost, and test results will be released later this year, but for now Lineback only could give us his target data. The motor is mostly made from composites so the weight should come in as low as 12 pounds. Instead of making many sizes of motors, Lineback will make just one. Because it is internally water-cooled with a special circulatory system, the power output can be as high as 75 hp. ICE motors can achieve from 25 to 75 hp only by using the proper controller size for the desired power output. According to Lineback, this is possible because the axial flux motor runs at maxi- mum efficiency at any rpm. The target price for the control- ler, special propellers, pitch controller, batteries (depending on flight-time requirements), motor, and all the electronics— in other words "plug-and-go" solution—should cost from $5,000 to $10,000. Flying Legend's supercharged Rotax 912 engine. The AeroMomentum engines are based on Suzuki "G" model automotive engines. The electric ICE motor, which can develop from 25 to 75 hp. Photography by Marino Boric