Douglas Fir wrote:

Paul

I would definitely be interested in side and end aluminum housings in

the

$500 to $1000 range and am sure I could even sell a ton of them here in
Japan as well. After repeated emails to Racing Beat without response

I'm

very happy to hear that Mistral will sell parts.  Thanks a lot Francois

for

your fine work and great information.

In the last week I  have come to the conclusion I need a simpler engine
mount to keep my planes cowl slim and Mistral's front housing design is

just

what I have in mind.

Doug in Japan

While you are at it Doug buy one of their gear boxes as well as you will
need a constant speed prop.

Paul

I agree I need a constant speed prop.  Isn't an electrically adjusting

prop

an option for me?

Doug in Japan

Yes it is but a constant speed is cheaper and better as it is metal
(thinner) and not wood.

Paul Lamar

Excuse me for coming with my grain of salt again.  I just went through the
exercise with various propeller manufacturers, as well as with our DER
consultants.

You can buy from Mistral a hydraulic c/s propeller that has been thoroughly
vibration and stress tested by its manufacturer on Mistral engines in
flight.  The prop manufacturer can then guarantee the full compatibility of
the entire system.  Of course, many other props will likely do the job fine,
but will always leave you with a nagging doubt.

Such an optimized hydraulic c/s prop is sold by Mistral between $6,500 and
$8'000 depending on the model and on the power of your engine, plus $1,350
for a great-quality governor which has proven to be much better for our
particular application.

Now, you can also easily buy a good second-hand prop and governor that will
do the job for $5-6,000 or maybe less... no guarantee, though.

A new electric prop (you will probably not find the right second-hand one)
will set you back quite a few hundreds if not thousands of dollars more.
It's maintenance costs (and headaches) will be considerably higher too.

I don't want to discuss the relative merits of metal vs wood vs composites
on the performance of the aircraft because it is very airframe and mission
specific.  IMHO, the lifetime costs and repairability of a metal prop can't
be beaten.

Francois

Tracy Saylor tried a German electric wood prop "optimized" by the manufacturer
for his application and it was 20 MPH slower than his metal constant speed prop.

Paul Lamar
 
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