Having talked publicly about its research into diesel- and hybrid-electric-powered light helicopters, Eurocopter has become coy as those plans get closer to reality.
The EADS company has two programs under way: BlueCopter to replace the single turboshaft in its EC120 with a diesel; and EADS Innovation Works' eCO2avia to develop a hybrid diesel-electric propulsion system.
Asked at this week's Heli-Expo show about progress with the hybrid-electric concept, CEO Lutz Bertlng said Eurocopter "is actively working on it", but would not say more because it was competively sensitive. Hmmm.eCO2avia. (Graphic: EADS Innovation Works)
As previously described, the eCO2avia has electrically driven main and tail rotors powered from four sources: two battery packs plus generators on two diesel engines. Batteries and engines power the helicopter for take off; engines power the cruise and recharge the batteries; and batteries alone are used for a quiet, clean landing,
As for the diesel, Bertling says he expects the slow-selling EC120 "to have a second life with diesel power, because it will become dramatically cheaper." A diesel will still burn jet fuel, but far more economically than a turbine. He says Eurocopter has selected a powerplant - it's a non-aviation diesel so needs to be certificated. A diesel-powered EC120 will not be available until after 2012-2013, he says, because Eurocopter has other priorities.
BlueCopter and eCO2avia will share diesel technology, Bertling says. EADS has previously expressed interest in EcoMotors OPOC
opposed-piston, opposed-cylinder engine. EcoMotors says the OPOC is 30% lighter, a quarter the size and 50% more fuel-efficient than a conventional modern turbo-diesel.
Sikorsky, meanwhile, has yet to fly its Firefly, an S-300C with its piston engine replaced by an electric motor and carrying battery packs in panniers, but expects to later this year. The 1,110lb of batteries will only give the helicopter 15min of flight time, but this is expected to increase as batteries improve. "If we can get to 1 hour flight time, we can change the training world," predicts Sikorsky president Jeff Pino.