Electric Assist Boosts Power 40 HP, Increases Safety, FD
Flight Design is developing a hybrid engine that their engineers
say will boost the power of a standard Rotax 914 by 40 HP for
takeoff and climb, and to stretch fuel at normal cruise.
At a news conference at AirVenture 2009 at Oshkosh, engineer
Oliver Reinhardt said that the engine is not designed for the LSA
market, but rather as a powerplant for a larger aircraft. "The
basic engine is not touched", Reinhardt said. The Rotax works as a
normal engine with no loss of power when the electric assist is not
In a background statement provided by Flight Design, the
electric motor is described as taking the place of an auxiliary
generator. It delivers power to the propeller via a V-belt
drive, which FD says will not overload the engine crankshaft. "The
electric drive doesn't care about density altitude", Reinhardt
said. He added that for pilots operating in very cold
climates where starting can be a problem, you can use a "40
Reinhardt said safety is enhanced by this hybrid engine. The
Rotax will operate normally should the electric motor fail, and
should the reciprocating engine fail, the electric motor can extend
the aircraft glide ratio, allowing the pilot additional landing
options. The lithium-iron batteries can be recharged in flight by
the standard engine generator, and the windmilling prop during
descent can also re-charge the batteries.
Flight Design claims lower fuel consumption and emission with
the hybrid engine. They say the electric motor provides 95%
efficiency at 7,000 RPM.
The engine is currently in bench test phase for proof of
concept. Flight Design says it plans to continue the ground
testing, and hopes to be able to fly with the engine later this
At the same news conference, Flight Design CEO Mathias Betsch
said he things the LSA market has a lot of room to grow, and that
the demand for LSA's will take off as the recession ends. They also
used the event to announce a new distributer for the western U.S.
Flight Design West in Las Vegas, a Cirrus supercenter, will
represent Flight Design in the region in conjunction with Lone
Mountain Aviation and Lone Mountain Aircraft Sales.