EAA Experimenter 19
ULPower from Belgium also builds engines in a normal
aircraft engine confi guration but with many modern features as
opposed to traditional manufacturers. Its engines range from 97
hp to 200 hp, also in air-cooled, fl at-four and -six confi gurations.
www.ULPower.net
We should note that the previous two engine lines get their
good power-to-weight ratio in part by rating them at a higher rpm
than Lycoming and Continental engines. That means to use that
higher horsepower they have to run a smaller-diameter prop and
thus lose some low-speed ef ciency compared to the Lycoming,
Continental, or the geared Rotax engines. You can't fool Mother
Nature. The acceptance of the above engines is helped by their
adherence to a conventional light plane engine confi guration of
fl at, air cooled, and direct drive.
That statement also holds true for the most common of auto
conversions, the VW air-cooled in one-half and four-cylinder
versions and the Corvairs in six-cylinder and one-third versions.
Another new contender in the cut-down engine arena is Pegasus
Power with one-half of an O-200. It is a parts kit of specially made
parts such as the crankcase, crankshaft, rods, and piston assemblies,
using as many stock O-200 parts as possible to make a fl at twin
O-100 of between 50 to 60 hp.
http://FlyPegasusPower.com/wp
Here's a list of websites featuring VW-based engines:
AeroVee
www.AeroConversions.com
Great Plains www.GreatPlainsAS.com/index.html
Hummel Engines (Scott Casler) www.HummelEngines.com
Better Half VW
www.BetterHalfVW.com/engine.htm
Revmaster
http://RevmasterAviation.com
Motorav Aircraft Engines is a division of a Brazilian company
that makes magnesium and bought VW's Brazilian magnesium
foundry. It has developed a much-improved version of the VW
with models up to 115.
www.Motorav.com
Corvair-based options can be found from these sources:
William Wynne
www.FlyCorvair.com
1/3 Ultra Vair
www.Ultra-Vair.com
There are air-cooled, fl at twin engines with propeller
reduction units:
HKS from Japan has stopped producing engines for the avia-
tion market, but some are still available. And more importantly,
it is still supporting its 80-hp turbocharged fl at twin engines.
Their well-regarded 60-hp carbureted engine is still available. It
is air/oil cooled with a gearbox reduction drive and comes in at
about 120 pounds.
www.HKS-Power.co.jp/hks_aviation , www.
GreenSkyAdventures.com
, www.QuickSilverNE.com
Verner Engines from the Czech Republic makes fl at twins—
air cooled, 80 hp, at only 60 pounds, and a 35-hp liquid-cooled
fl at twin engine.
http://VernerMotor.eu
Flygas has modifi ed what looks like a Citroen fl at twin by
the addition of a supercharger and a prop gearbox into a 70-hp,
12-pound airplane engine.
www.Flygas.info/en/index.html
The Hexadyne P-60 is going to be reintroduced. It is also a
60-hp engine.
www.HexatronEngineering.com/prod02.htm
William Wynne has educated people to the fact that they can make an O-200 class
engine for a fraction of the cost. William's conversion package is based on the
Corvair engine of the 1960s.
Pegasus Power has a kit of special parts to make a 60-hp, O-100 fl at twin engine
using O-200 cylinders and components. The custom crankshaft and lightweight
rods and pistons make for a smooth-running engine as demonstrated at EAA
AirVenture Oshkosh 2014 in the Utralight/Lightplane area.
AutoPSRU's offset up gearbox is quite compact and has a complete oil system,
including an optional prop governor.
Photography courtesy of Murry Rozansky