In a message dated 2/24/2007 7:55:29 P.M. Eastern Standard Time,
keltro@att.net writes:
Lynn,
And here I sit with a "Mistral" mount plate residing where
the
stock front cover used to be on my 13B.......It allows the use of
a standard Lycoming "Dynafocal" mount ring to bolt my engine
to my "Dyke Delta".....What do you think are the chances of
my
normally aspirated rotary from over-stressing its end-plates and
rotor housings......."Mistral" does have provisions for using a
four point bed type mount on the 13B (using their redrive) and
it is required on their 20B , three rotor
engine ......... Attached
photo is of "Mistral" 13B on a Glasair project of one the rotary
group, Steve Thomas in Calif.......Hope you do not mind Steve!!
--
Kelly Troyer
"Dyke Delta"_13B
ROTARY Engine
"RWS"_RD1C/EC2/EM2
"Mistral"_Backplate/Oil Manifold
Francios Had the reduction unit in the motor tent at Sun &
Fun about 5 years ago, looking like a lost puppy. They had been trying to get
the Piper to fly long enough without frying the oil so they could have it on
display at the flight line. No dice. I talked to him for a very long time. He
took notes. They are all engineers, and trust math to get them out of
anything.
So they calculated everything, and on paper there would be enough oil
cooling to do the job.
Well that test location was in Florida before Global warming had died
down. I suggested best power was down around 160 degrees max, and he was sad.
The coolers were big enough. The flow rate was high enough. Airflow
through the coolers was high enough.
The oil temp would just slowly climb into the red 230-240-250 and land
again.
They didn't realize the Mazda pump was designed to work OK at 2,000
crankshaft RPM.
So, at 6,000 RPM it foams the daylights out of the oil. And air in the
oil is an insulator, and the effect is that the coolers get smaller with time.
The oil pump has a front and rear segment and those are shaded just a bit to
reduce noise. Both must pull suction oil from the back end so the number of
sharp corners the oil sees inside the pump is more than a normal pump.
Plus, the higher flow was unhappy with the tiny bug screen at the end of
a sharp edged tube in the pickup. So, there was a vena contracta problem.
So, they took off the bug screen and it started working well. They took
out the airplane oil and put in car oil Fewer polymers, and it worked better.
They made up a dual pickup casting to feed both ends of the pump like the FD
oil pump and everything is fine.
The point of the story is that the mechanical parts have many actual
hours of flying in a real airplane in hot weather. So, it is thoroughly test
in a real life situation.
Their front Iron and mount is thicker and stiffer than the stock stuff.
There will be no problems.
Lynn E. Hanover