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Hi TJ
Tracy may not respond as he probably considers
Paul's comments not worth commenting on. But, here is my
take on it for what it is worth. This was my response to Mark's
message below:
....Do you know anything about possible mixture issues with constant
speed props? Paul mentioned it on his list. Something about not
having a air flow sensor, it assumes fixed load at any given rpm. Is this
something else to worry about. Yes, I'm running a c/s prop. Maybe
this is a Tracy question.....
I guess that since carburated aircraft engines
(Lycomings, etc) which also do not have an air flow they also
won't work with CS props as well. Sure a lot of money
spent for something that doesn't work.
Yes, you need some indication of engine load - but
manifold pressure reflects airflow into the manifold when the engine is
operating - no it doesn't when the engine is stopped, but then who cares at that
point. Low manifold pressure = low air flow , high manifold pressure =
high air flow provided once again - the engine is operating. I mean that's
the basis for the "Speed Density" fuel injection controller concept of the EC2-
which the best I can tell is working on numerous aircraft.
Tracy has a neat idea. With his "CS engine"
he can set the "fly by wire" TB to hold a constant rpm, constant manifold
pressure or constant fuel burn. Now like all engines, the set
up will only work with certain constraints. You can't take a 120 HP engine
and put the nose up for a 45 deg climb and expect it to hold 6000 rpm for
ever. But, within reasonable operating regimes it will work
fine.
Lets look at the three modes (my take on them - since I
haven't seen or discussed the concepts with Tracy - his may be considerably
different - more than one way to skin a grape,etc).
1. Constant rpm - very simple. The
module senses engine rpm and compares it to the value it has been instructed to
hold. If the engine rpm is below the target, the throttle is opened to
increase power/rpm. Once the target rpm is reached the throttle opening
stops. The module simply adjusts the throttle plate to maintain the target
rpm. Here the variable is the manifold pressure and the
constant (target) is the rpm. Just as you would jockey the throttle to do
the same. You take whatever manifold pressure is required to hold your
target rpm.
2. Constant Manifold Pressure - very
simple. The modules senses the engine manifold pressure and compares it to
the target value. If below the target value the throttle plate is again
opened and rpm increased until the target manifold pressure is reached.
Here the variable is the rpm the constant (target) is the manifold
pressure. You will take whatever rpm is required to maintain your manifold
pressure.
3. Constant Fuel Flow - a bit more complex.
Here you could probably vary both rpm and manifold pressure to achieve the
desired fuel flow. If the fuel flow drops, then the throttle is advanced,
manifold pressure increases and fuel flow increases as a result. When the
fuel flow is above the target the opposite happens.
Now, I am not certain that Tracy's implementation is as I
described above, but that's how I see the basics of such an
approach.
So you can certainly make up your own mind about it and I
am not a CS expert (never had one) nor have I slept at the Holiday Inn last
night, but that is my take on it.
I mean given that Tracy has never yet turned out a product
that failed to operate as advertised, I'll bet on Tracy any day of the
week. Why folks even listen to Paul's nonsense is beyond me, of course I
am still flying a "Plugs Up" installation that according to Paul's
decrees could never work - so what do I know.
There! my 0.02 on the topic.
Ed
----- Original Message -----
Sent: Sunday, April 29, 2007 7:55
AM
Subject: Re: Renesis CAS Connector
Ed,
I know what you mean about Paul and his quirks (warts). We all have
them, some more obvious than others. ;-)
Its good to hear that the "snubbers" are working. I was at my
witt's end trying to get my engine to run like I know it can. The best
it ran was with the fuel pressure dialed down into the teens. It idled
great, low rpm range was good, etc. Then I raised the pressure up
to about 30psi, and the symptoms returned. That's when I called
Tracy. I feel that he needs to get the word out to more customers like
myself, assuming that there are "more customers like me". Anyway, I'm
looking forward to smooth running.
Do you know anything about possible mixture issues with constant speed
props? Paul mentioned it on his list. Something about not having a
air flow sensor, it assumes fixed load at any given rpm. Is this
something else to worry about. Yes, I'm running a c/s prop. Maybe
this is a Tracy question.
Bobby and Paul butted heads over Bobby's motor mount design. That
was about a year ago, and now Bobby, and a few dozen others,
have convinced him that it was a bad design. It also had other
problems, like the mounting pads were out of plane, and the nose gear donuts
were rubbing on the mount tubes. So, we've come up with a way to use his
original Van's mount and make it work for the Rotary. I'm not sure who
is doing the mod, maybe Jerry. ???
I got a ride in a RV-7 this weekend. Nice airplane. But
powered by a Lycosaurus. It had a 3-screen Grand Rapids glass panel and
a Garmin 430. Can you say information overload? I hear that you
can turn off various features of the Grand Rapids. I would have to do
that until I was more comfortable with the basics, then add features
one-by-one.
Mark
(new grandpa)
On 4/28/07, Ed
Anderson <eanderson@carolina.rr.com>
wrote:
Hi Mark,
Getting long in the tooth for sure, but having good
genes - my 85 year old working Uncle met me when I landed in Louisiana - I
hope to put off the "wandering" a few more years {:>)
Glad to hear your fire alarm is working - neat gadget
- might be a market for such an item - you could start you own business and
no more working for in-laws {:>)
Yes, get it done right at your own time table - we can
wait for that first problem-free flight.
Saw Bobby Hughes at S & F and he said Paul L had
apologizes (or as close as he would get to one) for "hurting" Bobby
feelings.
I think Paul was feeling a bit unloved at S & F,
he struck sparks with just about everybody including Tracy by announcing
that RWS would sell Paul's "How to cool your Wankel" book. Tracy had
not agreed to that but as I told Tracy, if you don't unequivocal tell
Paul "NO!", then he assumes the answer is "Yes".
One acquaintance who teaches physics at a North
Carolina college told me he though I was on to something with my
explanation of my "pinched - necked down" cooling ducts. Well, Paul
over heard him and tried to poo -poo the ideal that I may have come up with
something that the master had overlooked. I just told him to keep it
quite as my ducts didn't know they weren't suppose to work and my airplane
had been cooling fine for years. So there was no reason for me to buy
his book.
He finally forced one in my hand, so I opened it to
take a peek at what Paul had written/borrowed on "Wedged ducts" and found an
error before I had read 3 sentences. Even Paul agreed it was an error
- so he took the book back. I was told several more errors had been
found before the day was over - not that having a few errors in a book is
something rare - but, I think Paul almost felt I had found it on purpose to
dig at him.
Well, not having been on his list for the last
three or four years has been very nice. He even told folks that I had
left his list and started one of my own (Fly Rotary) which was clearly a
falsehood - OR he really is starting to lose his facilities.
In any case, Sun & Fun was great fun and watching
Art's FWF rotary run was great if for no other reason that it bothered Paul
a great deal. It was a nicely put together installation which
will certainly get better as time goes along.
Well, back to reading about how to set up a Limited
Liability Corporation.
Best Regards
Ed
----- Original Message -----
Sent: Saturday, April 28, 2007 9:11
PM
Subject: Re: Renesis CAS
Connector
Ed,
Gald to hear from you. I was beginning you may be having a
senior moment and may still be "wandering in the
wilderness" at SNF. Good to hear you had a good time and that
your new fangled gizmo was so well accepted. So, working for
yourself can be tough, but not as bad as working for your
in-laws. ;-0)
As for the CAS connector, I vaguely remembered someone saying that
the Mazda fuel injector connector could be made to work. I tried it
yesterday and sure enough, with a few minor mods, I was able to get it to
mate up like it came that way from the factory. So, that's
behind me now. I'm waiting for Tracy to return my EC-2, followed by
a little re-wiring and then we'll see how well the "snubber upgrade"
works. I sure hope it cures the tuning problems of the
3-rotor.
Nobody is more anxious to get the first flight done than me.
You guys will be among the first to know when I finally "get 'er
done". Right now I'm starting to get back into the saddle (flight
training, bumming rides, etc.). I've been building for way too
long. Its time to remember why I started down this path in the first
place.
By the way, I have the fire detector installed and it works like
a champ (laboratory conditions only). Hope I never see that big
red warning light lit while flying.
I also got the GPI (ground proximity indicator) installed
today. That's the gauge that helps me flare by telling me how
high I am above the runway (3ft or less) via a bar LED. I
won't be able to test it for real until I'm flying. It looks like it
will work as intended, but there is nothing like the real world to reveal
the warts.
See ya,
Mark
On 4/28/07, Ed
Anderson <eanderson@carolina.rr.com > wrote:
Hi Mark,
I detoured to Louisiana after Sun & Fun, so
just got back home late yesterday. Sorry, can't help on your
connector. Have not really done any research on the Renesis as I
am still flying the old hardware.
Bob white may be able to help - but, I've always
found my Mazda unique connectors at the junk yard. Had a great
time at Sun & Fun, demonstrated my EFI system monitor with the new
colored OLED display and seem to have some serious interest.
Egads! I may find myself working for myself despite my vows never to do
so {:>)
We are eagerly awaiting for your first flight - so
keep at it.
Best Regards
Ed
----- Original Message -----
Sent: Monday, April 23, 2007
12:09 PM
Subject: Renesis CAS
Connector
Hi Ed,
Have you recovered from SNF? There has been very little
information posted on the Fly Rotary about the "latest and
greatest". I'm assuming that you went this year. No,
I didn't go, instead chose to stay home and work on getting the
airplane finished. (is it ever really finished?)
With your extensive electronics knowledge, I was wondering if
you know of a source for a Renesis CAS connector?
I'm converting my engine to the newer Renesis style crank trigger and
have everything worked out except for the connector itself.
Anyway, I haven't yet checked with Bob White, or Bob Mears, but they
are on the list of people to check with. Final option will be to
scrounge the wrecking yards for a suitable connector. Tracy is
updating my EC-2 to work with the Renesis sensor. So, all I need
is the connector. Any leads would be appreciated.
Thanks,
Mark
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