Hi, Paul....I wish to pick your brain for ideas. I am building an SQ2000 with a 13B. It would be
very nice if I could start a small business using my aircraft and selling a rotary related
product, which I could fly to various fly-ins and promote such a product, similar to the way
Tracy
and others do. (I would like to incorporate the airplane into the business, and amortize it).
What
I am looking for, is a suggested product I might be able to produce and advertise on the
internet,
and show at various flyins that complement a 13B engine installation. I don't wish to get into
redrives,or installation manuals, or step on Tracy's feet.(He is already doing a fine job with a
fine product) I also would pass on motor mounts, as Jerry Hey and others are going down that
path. I am looking for a project that I might be able to specialize in, and I thought, "who
better
to ask than the Mazda GURU, Paul Lamar"? I have some money to spend on development of the
product. Just looking for something that will be of use and possibly in demand. Thanks in
advance
for your thoughts/ideas. Paul Conner, Mobile, AL
Complete 321 SS & Inconel exhaust systems. Tried and true.
Start with the RV series. I'll make some engineering suggestions
as you move along. Build a test stand to test them before you risk
flying them.
Paul Lamar
I would be interested in a couple of other products that seem to be scarce. 1. Exhaust augmentor.
This would be a natural in pusher applications like my LongEZ. It could provide plenty of suction
for radiator airflow during taxi and low airspeeds and add a little additional thrust. If it is
possible to develop a multiple stage unit I think it would also quiet the exhaust. I understand
that current augmentors are quite loud.
2. A PSRU with a vertical offset. Tracy's RD1A looks like
an excellent unit but is a straight trough design. I am hoping to be able to drop my engine a
little lower while raising the prop about an inch. Ken Welter's belt drive has a reasonable price
but I think the offset it too much and I don't know if he is too busy rebuilding his Coot to build
PSRU's. I like the configuration of the Powersport unit that uses the internal ring gear with an
offset of about 3 inches, but the price is $6500. Ouch. If someone can come up with these systems
at a reasonable price, I might be their first customer. I would even be willing to help test
prototypes since I will be doing my early flying within gliding distance of the home airport (D W
Hooks in Houston), and the runways have landable farm land just beyond the runway ends. Dick
Gregory LongEZ N613NC
Dick, I think you will find any spur gear PSRU that provides offset not worth
the extra weight. It remains to be seen if any of them last as long as a Ford
six pinion planetary. The reason for this is a thing called gear line
contact length. Almost any planetary has much more gear line contact length
than any spur gear PSRU of reasonable size. The stresses are highest in the
gear line contact. The gear line contact length on a Ford six pinion is about
5.4 inches long in total. To get this in a spur gear transmission
results in a monster gear box. Here is a picture of such a spur
gear PSRU. This is out of an S51 and the box weighs over 120 pounds.
The line contact length is still only about three or four inches.
The vast majority of successful geared aircraft engines, and that
includes huge radial piston engines, almost all turbo props and some
turbo fan engines, use planetaries for that reason. The WW II liquid
cooled V engines are exceptions because they really need the off set.
We have ten of thousands of accumulative hours in 100's of Ross's
and Tracy's PSRU's.
Why do you need the offset?
Paul Lamar
The AirCraft Rotary Engine NewsLetter. Powered by Linux.
ACRE NL web site. http://home.earthlink.net/~rotaryeng/
Copyright 1998-2002 All world wide rights reserved.
