Paul:

Am I correcting noting that this single rotor Austro  engine has a built in
supercharger?

It appears to be a nice, clean  package, but for a Mosquito, more power is
needed.  An ideal rating  would be between 80 to 90 hp.

George

That is a rotor cooling  blower and not a supercharger.

Paul Lamar

No,

The Austro, as far as I can tell is the Midwest RAE50 which is now being
sold and manufactured by Diamond. It is my understanding that this engine  is
certified (JAR something). Before Diamond closed Midwest, they were also in
 the process of certifying the 2 rotor. Diamond owned Midwest.

What looks like a supercharger is actually part of the cooling system. The
trochoids are liquid cooled, however the rotor(s) are cooled differently.

There is no oil sump in this engine. The oil is metered into the roller
bearings as well as the trochoid(s) from a reservoir . The oil in the
trochoids, of course is burned, but the oil to the bearings then finds its way  to
internal fins of the rotor(s), where it is picked up by a fan like  device
that you identified as a  supercharger. This fan is belt  driven and takes
atmospheric air, through a filter, blows the air and now oil  mist through the
rotor(s). picking up heat. It is then dumped out of the engine  through an
air/oil separator (not shown). The reclaimed oil is returned to the  oil
reservoir and the cooling air and un-reclaimed oil is vented overboard. The
cooling air is ducted to the rotors through the white silicon rubber hose and
exits through the visible ports at the front of the engine. This system was
 actually used in the original Norton engines (of which these are improved
clones)

Rich

No what?

So it is a fan and not a blower? Fans are axial flow devices
and this one is a centrifugal blower much like a centrifugal super charger
except it is lower output pressure.

I identified it as a blower and my friend George thought it was a supercharger.
In these pictures you can clearly see the shape of the blower scroll.
You can also see the larger version they were working on as far
back as 2004. Some of these picture I took at the Diamond factory
in March 2004.

Yes the engine is primarily liquid cooled.
As far as oil cooling the rotor that is not the oil's primary function.
A Mazda engine has a true oil cooled rotor. Perhaps some oil finds it way
to the rotor cooling fins but the blower is the primary method of cooling
the rotor with air. It is not a charged cooled rotor engine like the Rotamax.
It is a straight forward p-port engine with an air cooled rotor.

BTW They might get a bit more power if they routed the rotor cooling exit air
back into the intake system.

Yes it is mostly the same as Norton and Midwest. The name has been recently
changed yet again.


Paul Lamar