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This was the reason I was hesitant to bring this up
in the first place. Because I didnt want to put Tracy in the position of
having to get involved in a lengthy on-line debate. I ultimately decided to
bring this up because I've had numerous direct emails asking why my flight
tests seem to have come to a halt. I'll emphasize again, based on the success of
other users of the EC2, that I believe that my current issues
are installation related, not design related. Hopefully the changes
I've made will resolve these issues and my flight testing can resume
normally.
Had my original plans worked out my single point
ground should have worked out well with my battery located directly under the
EC2 per Vans plans. Unfortunately, my RV is a nose heavy pig and the batteries
ended up in the baggage area. I should have abandoned the single point ground at
this point and grounded the battery to the airframe. I didnt do that and
stubbornly stuck with the single point ground, so I now have about 7' of 0 gauge
wire between the negative terminal of the batteries and my common ground on the
firewall. This is the first thing Tracy told me to change. While making the
change, there were a number of other things that needed changed as well. As a
result of this and a number of other unrelated issues, I havent gotten the
airplane back together enough to test it. Hopefully in the next couple of weeks
I'll have it together again.
Mike Wills
RV-4 N144MW
----- Original Message -----
Sent: Monday, April 27, 2009 10:56
AM
Subject: [FlyRotary] Re: Electrical
System Nightmares
Position 0 (zero) is where the Mode switch should be for
starting and shutdown.
My experience so far indicates that
electrical noise in various parts of the electrical system is the cause of the
'spontaneous' programming errors. This is a long subject that I am going
to have to address. It has to do with the physical arrangement of the
aircraft electrical system, not an error in connections. There is
no one simple fix for this kind of problem which is caused by builders
having no guidlines on how to avoid this kind of thing. Bad radio
installation practices or poor antenna design or installation can also be a
nightmare to explain or fix.
I talked to a number of vendors of
aircraft systems at SnF that are having a hell of a time addressing this.
Everything from auto pilots to Glass cockpit makers are having this
problem. Builders always conclude that we are passing the buck when we
say that electrical noise is the problem. And that's just a polite way
of saying that "Your electrical system and layout sucks". Even
very knowledgable builders can fall into this problem. Mike Wills made a
technically perfect system with a Single Point ground scheme which is
theoretically the right thing to do but the single point ground had a very
high noise impedance due to the long distance between it and the main noise
damper (the battery).
Here is a VERY abreviated guideline. If
you do a single point ground system, make it at (or very near) the
negative terminal of the battery and ground the airframe close to
it. Have independant power feeds from the battery positive
terminal for the noise producing things and the noise sensitive
things. Do these two things and noise problems will be
rare.
I'll try to write up some more detailed guidelines on the subject
when I get the mess left by the flood cleaned up.
BTW, SnF was great
fun and enjoyed seeing many of you rotor-heads there. Only trouble was a
failed fuel transfer pump on the way back home. Pump (and plane) is 15
years old. I noticed it shortly after switching it on because left
fuel gauge didn't go up and right gauge didn't go down but I had just
enough fuel in left side to make it back. Kept lots of alternative landing
strips in sight along the way. Only had about a gallon left after
landing. Pay attention to those fuel gauges!
Had to
wade back to the house because road into Shady Bend was still under
water.
Tracy Crook (doing flood cleanup)
On Mon, Apr 20, 2009 at 12:24 PM, Bill Bradburry <bbradburry@bellsouth.net>
wrote:
Rino,
Are you
saying that you SHOULD or SHOULD NOT stop and start the engine with the
switch in position nine?? I assume that you are only talking about
when you are trying to change the programming??
Tracy??
Bill
B
From:
Rotary motors in aircraft [mailto:flyrotary@lancaironline.net] On Behalf Of Rino
Sent: Monday, April 20, 2009 6:05 AM
To: Rotary
motors in aircraft
Subject:
[FlyRotary] Re: Forced landings
I had a memory loss similar to
yours on the A controller a few times when I was programming the
mixture. I then realized that it appened when I left (forgot) the
push switch on position 9 of the controller, stop and start the
engine. Stop and start the engine while the switch is in position 9
instead of 0. Never happened again after that.
----- Original Message -----
Sent:
Monday, April 20, 2009 12:50 AM
Subject:
[FlyRotary] Re: Forced landings
I got my staging issues
under control by following others advice and moving the staging point up
in the RPM range.
Unfortunately I have had
two random cases of the EC2 loosing pieces of its non-volatile
memory. The last case was the worst - the entire B program appears to have
been lost. It would not run at any throttle setting on B. Fortunately I
found this on the ground during a preflight runup. Copying A to B restored
the program and the engine runs fine. I'd sure like to find something
conclusive to indicate what happened, but this was 2 random events in over
20 hours of engine running and I have no idea what triggered it.
I've exchanged emails with Tracy and he says its likely a grounding
issue. So I've spend the last month going through all of my wiring looking
for some sort of problem. Havent found anything on the ground
side.
As mentioned previously
I do have a little hum noticeable in the headset when the alternator is
energized. I was preparing to look into this - dug out the O'scope and
everything - when the stupid fuel tanks (both) decided to start
leaking 1 1/2 years after I first put fuel in them. Just about have
the leaks resolved and time to get back on the electrical. If I can get
rid of the hum then I'll probably still be looking at a couple of hours of
ground running before I'm willing to fly it again.
Intermittant problems
suck. Thing is you never really know if whatever caused it has somehow
been fixed unless you actually find an obvious smoking gun. Not clear to
me that I am going to find that.
I've been hesitant to
post about this unless/until I had something conclusive. Didnt want anyone
to leap to the conclusion that there is an EC2 issue. I assume that
whatever it is, its particular to my install.
----- Original Message -----
Sent:
Sunday, April 19, 2009 11:01 AM
Subject:
[FlyRotary] Re: Forced landings
Mike,
What kinds of problems are you having?
Looking back over your posts, it looks like you were having problems
with the staging set right over your approach power setting. What
else is happening and have you moved the staging yet?
Bill B
From:
Rotary motors in aircraft [mailto:flyrotary@lancaironline.net] On Behalf Of Mike Wills
Sent: Sunday, April 19, 2009 11:24
AM
To: Rotary motors in
aircraft
Subject:
[FlyRotary] Re: Forced landings
OK, I can accept that.
It may seem from some of my recent posts that I'm down on the
rotary - not the case. I just want to make sure that we paint a fair
picture which is frequently not the case on an enthusiasts
website.
I'm probably a little
negatively biased right now having done my first couple of flights, come
across a couple of problems that are unresolved, and am currently
grounded. I really want to fly this thing again but havent had as much
time as I would like to fix the problems and get it airworthy
again.
----- Original Message
-----
Sent:
Saturday, April 18, 2009 1:08 PM
Subject:
[FlyRotary] Re: Forced landings
I understand and
agree with what you are saying regarding the experimental nature of
these one off installations. But if you dont compare them to the norm,
what do you compare them to? I guarantee you that is what the LyCont
flyers are comparing them to
Mike;
Sorry I
wasn’t clear – I meant it wasn’t a fair comparison during the first
couple hundred hours, while we are still in the debugging phase. After
tha, go ahead and compare. If we can get to some comparable
reliability level in that short a time, compared to their 100’s of
thousands of hours, we’re really on to something.
I’m
actually not an avid proponent of alternative engines. I just
happened to have chosen that route, and it’s been a rewarding
challenge; and working well.
Al
G
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