From: "John Slade" <sladerj@bellsouth.net>
Date: 2005/06/06 Mon AM 10:49:51 EDT
To: "Rotary motors in aircraft" <flyrotary@lancaironline.net>
Subject: [FlyRotary] Re: EC2 problems - solved / rotary risks

Thanks, Al.
After a slightly bad start, this is starting to get very informative and
interesting. Please keep it coming.

In the case of the wire/connector, I'm not really worried about it because
it'd not an engine out thing, just a loss of communication with the engine
monitor.

I like the "best asset is that I know I'm an idiot" theory.
It works well for me because Rusty keeps reinforcing it. :)
John

  -----Original Message-----
  From: Rotary motors in aircraft [mailto:flyrotary@lancaironline.net]On
Behalf Of al p wick
  Sent: Monday, June 06, 2005 9:58 AM
  To: Rotary motors in aircraft
  Subject: [FlyRotary] Re: EC2 problems - solved / rotary risks


  When we are pursuing a problem like Johns, we are eager to find the cause.
It's a great relief when we do. We say "Eureka!". We did it! We did it! This
sense of relief is a root cause for failure. We are so eager to get the
problem off our back, that we don't take the next step....
  Yes, I know you firmly believe this connector was the problem. But if you
can force yourself to pretend it WASN'T, then you can do this:
  Is the cause logical? Like is that really the wire that causes that
effect? If I remove that wire, does it have the same effect? What if I have
two things causing the same thing? By pretending that really wasn't the
cause, then you will do some more testing, looking around. Looking for
similar connector issues, stuff like that.

  Now I have to admit, this really does sound like he found the cause. But
I've seen this scenario so often. So you use the disciplines I suggest to
reduce your risk. Logical cause? Can I make it recur?
  Repeat after me: "Al Wick is an idiot". "Al will jump to conclusions". If
you believe that, then you start finding ways to prove your theory with
facts instead of just accepting your first conclusion. My best asset is that
I know I'm an idiot.

  Yeah, yeah, I know, you guys already knew I was.

  We had a perfect example of this on Cozy list couple weeks ago. Subaru
engine slipped 2 teeth on timing belt. Would no longer start. Keith talked
to expert and the guy said:"You know, the engine normally is never rotated
backwards. But you've been pushing your new prop backwards recently
(installing new prop). I think you relaxed the belt tensioner when going
backwards and caused it to skip tooth." So Keith said" Yes, all of that's
true. That has to be it."

  But then one of the guys looked into it, guess what? The direction the
belt slipped is the opposite of that theory. That could not have caused it.
  The lesson? Prove all aspects of the theory are logical. Prove that all
the various facts support the theory. Find a way to convert your theory to
facts!

  Oh, by the way, if you look at my analysis of my engine risks....you will
notice that timing belt is the highest risk item on this engine. So we have
exposed another root cause for his problem. He didn't focus on the leading
cause for all engine failures. When we reviewed some facts he had, we found
conclusive evidence he had loose belt from day one! It was installed wrong.

  Regarding CAS risk. It's not just crank angle sensor that is the risk
item. Going to redundancy with the CAS will dramatically reduce risk of all
ECM causes. Like this connector risk. I'm not always proponent of
redundancy, but with my limited info on this item, I SUSPECT it's
significant, positive step.

  -al wick
  Artificial intelligence in cockpit, Cozy IV powered by stock Subaru 2.5
  N9032U 200+ hours on engine/airframe from Portland, Oregon
  Prop construct, Subaru install, Risk assessment, Glass panel design info:
  http://www.maddyhome.com/canardpages/pages/alwick/index.html




  On Sun, 5 Jun 2005 21:44:00 -0400 "Tracy Crook" <lors01@msn.com> writes:
    Ahh..  Music to my ears John : )

    And this brings up the subject of risk (rotary & otherwise) that Al W.
(and every other builder I know) is concerned with.  I agree with Al W. that
getting to the major causes of failures is a (hell, THE) key issue.  That is
why I have not spent much time on the crank angle sensor single point
failure question.  I have never seen or heard of a confirmed Mazda 13B CAS
failure.  Can it happen?  Of course.  I am in the process of developing a
dual CAS for the Renesis CAS but it is not a 'front burner' project.

    I'm reading between the lines of Al's posts but it seems that he is
emphasizing the importance of leaving the engine as un-touched as possible.
I once wrote an article for Light Plane World (EAA's ultralight magazine
back in the late 80's) and advocated the same thing after noting that many
Rotax failures  occurred soon after the owner opened up the engine for
maintenance.  Decarboning the piston ring grooves was important but many
builders were causing more problems than they fixed when they went inside so
I recommended some products and procedures that would do the job without
opening the engine.

     That was the basic gist anyway but I eventually decided this was not a
reasonable approach for builders who planned on installing an alternative
engine in 200 mph category airplanes.  There were simply far too many areas
where things could go wrong in this process.  The root cause of the problems
had to be identified.   One of the names I gave to the cause is a term I
recently used on this list - Shopcraft (or lack of).   This referred to the
ability to identify the quality or suitability of virtually everything that
goes into the plane.  Yes, I know this is a generality of the highest order
but if we are to get to the root cause of failures in the field of
alternative aircraft engines, this level of abstraction is required.

    It has been suggested that a collection of 'best practices' might be a
solution.  This may help but it is not a solution.  There is an unlimited
number of potential problem areas so a list of them could never be compiled.
So, how do you learn to recognize what is or is not a 'good thing'?   I'm
getting so frustrated just trying to describe the problem that there may not
be a solution, at least not one that can be spelled out in something like an
email message.   Damn, now I can't even criticize Al W. for not spelling it
out.

    The best I can do for now is to emphasize two things.  Pay attention to
every detail and admit to yourself when you don't have the ability to
execute something well.   Another version of these rules was given to me
long ago:

    1.  Rules are for those who are not smart enough to make up their own.
(Author unknown)
    2.  A man's got to know his own limitations.  (Dirty Harry)
    3.  Always follow BOTH rules 1 & 2.

    Small details like the problem of soldering thermocouple wire to a
connector that Al Gietzen mentioned can be critically important.  He was
able to recognize the problem (he made a lousy solder joint) and devise a
solution (acid flux) even though it violated one of the cardinal rules of
electrical wiring.  He recognized that too and took the steps necessary to
achieve satisfactory results (knowing when to make up his own rules).

    Out of time, I'll stop blathering now.

    Tracy

    Subject: [FlyRotary] EC2 problems - solved


      Tracy and others.
      Following more than 12 months of battling with EC2 issues I'm pretty
sure it's Eureka day!
      After rewiring and testing for almost 4 weeks I plugged the EC2 in
last night, and got exactly the same symptoms as before. NOP flashing
indicating no communication. I took the EC2 to Buly's plane and tried it in
his installation. Same NOP, so I was thinking I'd fried it again. Before
sending it back yet again I decided to install it my plane one more time and
see if there was a spark.

      To my amazement it worked. No NOP, and I could bring up the EC2 data.
The only thing that changed overnight was that I moved the cable to unplug
it. I climbed in the back and found that I could make the NOP flash, or stop
flashing, by moving the cable. I haven't taken the connector apart yet, but
I'm expecting to find a broken wire inside the insulation, probably near a
solder joint at the pin. Whenever I bent the connector outward for testing
it made contact. When I bent it back to plug it in, contact was lost.

      Bingo!
      John

      Just guessing, but maybe the new EC2 can't communicate with a
pre-autotune EM2 like Buly's. ???