Paul

 For your files.  A prop extension.  The inner boss doesn't look
 like it extends one inch upwards though.   Source is AirCraft Spruce
catalog.
 Say recently  Google has linked images to a website.  Much faster
 to located a known technology.

 Check out this companies compact SR  water cooled alternator/ and
 starter motor.  Nice and compact.   SR is is a very efficient way
 to use the electric fields.   It is not easy to do though.
 Good-bye starter ring and starter?

 http://www.cpowert.com/products/speedstart.htm

 Doug in Japan

 What does that sucker weigh ? :)

 Paul Lamar

 --


 Paul

 C power  didn't develop the technology.  They are a customer.   The
company
 that developed it was SR Drives in England which is
 wholly owned by Emerson of St. Louis. USA.

 I have yet to find out the weight but because the rotor has no
 windings and these puppies are super efficient my guess is about 17 lbs.

 Here is Emerson's site.    I am now involved in designing a small
 hydro electric generator of 1 to 3 kW range and water cooled SW is
perfect.

 Mistral asked me about this years ago.  Say what is happening
 with Mistral anyway?


 http://www.srdrives.com/starter-generator.shtml

 Cheers

 Doug in Japan

 Mistral ran out of money.
 They made the following errors:

 1. EFI. Should have put an A/C carb and mags on it.
       Lycoming is now in the same position. At least
       they are exploiting the experimental market.
       The FAA don't do EFI.

 2. Refused to sell parts to the experimental aviation market.
  Priceless free R&D.

 3. Wasted time and money trying to get it to run on Jet A.

 Paul Lamar

Paul,

Agreed.  I would add one more.  Failure to explore the merits of
the P-ported engine.

Does that mean their company is gone?  What about that lovely PSRU?
I would love to produce something like that. Perhaps design it so a
higher gear ratio could also be used and use a different resonant damper.

Doug in Japan


Its gone. I don't know yet who bought the assets if any.
They had a 3 rotor powered Maule in Florida.


Paul Lamar

Paul,  I am not sure that the EFI was necessarily a bad move, just offered
before the market was willing to accept it.With FADEC systems now being well
received by the certified engine buyers it won't be long before EFI is
offered and expected. We now wouldn't buy a car without it or an outboard
motor if it is offered. If they had used some type of Bendix throttle body
injection it would have helped with the FAA but also raised the price even
higher. And their pricing higher than the Lycoming engines of the same HP
gave little incentive to switch to their product. All the tangent programs
like jet fuel R&D had to force the price up. The real interest in their
product was with experimental builders and crop dusters etc.  They didn't
apparently even get a STC for some common airframe like a Cessna 172 type
aircraft.
     When talking to sales reps at their booth at Sun-N-Fun they were
disinterested in their rotary engine products, didn't seem to know much
about them and the Mercedes diesel conversions they were interested  in were
very heavy for the HP. No figure on weight was available when I asked them.
There has been far more useful information on the newsletter than on the
Mistral website when they had one.  One US distributor selling the PSRU for
rotary applications and possibly a bell housing section for an LS7 Chevrolet
and 351 windsor Ford IMHO would have kept them on life support long enough
to get organized. Bud Warren is selling a  well made constant speed PSRU for
around 15K and getting sales. The Mistral PSRU at that price is about 40%
??? of their engine package with much less complicated machining, lapping,
and parts count in general as a percentage of the total engine. They were
also produced before Bud Warren announced his product.Both of these constant
speed offerings allow higher HP than Tracy is comfortable about with his
PSRU which would indicate a market for the product.Also lower HP 2 rotors
wanting constant speed as an upgrade might show some interest. Not catering
to the experimental market was a tragic stupid move on their part.
       I would have thought that fuel consumption might have been
in Mistral's  favor as a marketing incentive. It is often printed in
magazine articles that liquid cooled smaller bore auto conversions are 30%
more fuel efficient than the big bore air cooled certified engines. It is
also said that rotary NA engines use 5 to 10% more fuel than the liquid
cooled  recip auto engine conversions. This appears to indicate that a
rotary uses 20 to 25% less fuel than Lycoming products.  Having BSFC for
examples of each type all from the same source would be a marketing
advantage for one of the types but no one seems to want to put it in their
advertising.

george grimes

It is not the market that is the problem.

It is a bad move if your are trying to get it certified.
Lycoming is having the same problem as we speak.

The FAA employees are not smart enough to deal with EFI.  They
are just overpaid Federal government workers with degrees
in basket weaving. (liberal arts......literally :) )

There is absolutely  no real reason to use EFI in aircraft
engines. Carb and constant dribble mechanical fuel injection
work just fine.

The control requirements are vastly simpler in a constant
RPM engine and in most cases constant load. I might see it justified
for turbo engines and perhaps constant speed props.

I don't buy the 30% lower BSFC. A well adjusted aircraft
engine with carb can get down to .45 BSFC. 30% less than
that is .32 BSFC. The leaned rotary is .47 BSFC

I might buy .4 BSFC for cars. That hardly is worth it
for A/C as the back up electrical system required is a huge
draw back over a couple of mags.

.32 BSFC is lower than most if not all diesels at low power.
Diesels running at 80% power are not worth the weight
as the BSFC is almost as high as a gas engine. That
is why diesel aircraft engines have all failed starting
in 1930. If you buy a $750,000 airplane you expect it
to cruise well over 200 MPH. You are not going to
get that speed running a diesel at 50% power.
Do you remember the highly touted Continental 2 cycle
diesel of a few years ago they wasted 20 million
dollars of our money on?

If I had the money spent on R&D for every car V8 tried in an
air craft and failed I would be wealthy beyond my wildest
imagination. http://www.rotaryeng.net/DS-smith-art.pdf

Those that fail to learn from history are doomed to repeat it.


Paul Lamar