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Boy, had memory of the journey to get to
Pecan Plantation – bitter cold in my cockpit – OAT reading 12F
flying from Mississippi
to Pecan without a stop. Almost drug a wing tip when the gusty wind at Pecan
bounced me all over the place. But, well worth it once we got inside and got
to talk to all you folks and enjoy the hospitality that Bill and Linda Eslick
and other’s provided..
Yes, I first met my hero in Thomasville, GA flying in
2000 – had talked/email with Tracy
every since I saw his photo on the cover of Kitplane in 1995, but didn’t
get to meet him until then. Fast friends ever since and ever more.
Ed
From: Rotary motors in aircraft
[mailto:flyrotary@lancaironline.net] On
Behalf Of Chris Barber
Sent: Tuesday, March 16, 2010
12:37 PM
To: Rotary
motors in aircraft
Subject: [FlyRotary] Re: Ut-Oh...
Agreed. My concern is that Tracy is my projects
greatest "single point of failure" should he decide to put all this
nonsense and our silliness behind him and just call it quits and
actually retire.
Tracy, thanks for the continued thoughtful support and hanging in
there. Your knowledge and support is appreciated more than I/we can
express. Kinda funny as my "ex" made fun of me when I
first met you at Pecan Plantation at the cold Texas rotary round-up a few years a go...she
thought it was so funny that I was "meeting my hero". Well, she
was kinda right. ;-) Thanks.
From: Rotary
motors in aircraft [flyrotary@lancaironline.net] on behalf of
David Leonard [wdleonard@gmail.com]
Sent: Tuesday, March 16, 2010
12:17 AM
To: Rotary
motors in aircraft
Subject: [FlyRotary] Re: Ut-Oh...
Hear Hear!!
Dave Leonard (or is it
Here Here?)
On Mon, Mar 15, 2010 at 9:26 PM, Mike
Wills <rv-4mike@cox.net>
wrote:
Just in case its not
clear, I think most of us here appreciate how tough it must be for essentially
a one man show to play such a key role in our pursuits here. Thanks for making
my airplane possible Tracy.
Sent: Monday, March 15, 2010 9:46 AM
Subject: [FlyRotary] Re: Ut-Oh...
You make a
lot of valid points Al. Don't always agree on the conclusion but the
points are good. For example, your idea for the "are you
sure?" step for mixture adjustment would hamper the immediate action of
adjusting the mixture as one of the first steps I recommend when ever any
engine running problem occurs. There is a LONG list of reasons for doing
this and it has saved my bacon on many occasions, especially during early
development.
No argument, there ARE a lot of 'small' (ha!) changes I could make to improve
things. Cost, complexity and time are major factors why I
don't. That last one is a biggie. I spend well over 40 hours a week
just trying to keep up with current demands in a business that I had no
intention of getting into and would gladly turn over to someone else if that
were possible. (I tried that once on a limited basis and it was a
disaster)
Fundamental changes that affect basic function and safety are a different
matter. When they come up everything else gets dropped and the problem is
addressed as quickly and completely as I know how to do.
So yes, what I am offering is only the best I can do with the time and
resources I have available. It is far from the best that can be done.
And yes, I know there is the chance that I could be hearing that line from some
grieving widow's lawyer someday. Another great aspect of this
thing. Some risks you just have to live with.
Tracy Crook, RWS
Another dead stick landing. Same old
causes. Fortunately no fatalities....this time.
Let's pretend you are the copilot. You've
been flying along for 10 minutes. When the pilot says: "Hey Bob, how about
giving me 150 times as much fuel right now." You'd
say:"WHAT?!! You are crazy, that will shut down the engine!"
Pilot:" Oops, my bad. O2 and egt's
are normal. My mistake"
Does that sound far fetched? Nope. It
happens a couple times a year. Often it's a case where the pilot inadvertently
drives the ecu to super lean condition. Engines suddenly quits. Let's use
your home pc as an example. You tell the pc to delete all files on your hard
drive. It recognizes this is most unusual and could be catastrophic. So it
says:"Are you sure you want to wipe out hard drive? This could be
fatal"
Every failure has more than one cause.
Yes, the pilot inadvertently flipped the "cold start" switch when he
was reaching for his gps. Was it Ed last year who inadvertently rotated the
mixture to full lean? Last year Keith's passenger bumped the ecu
mixture knob while getting in the plane. So, yes, Ed, Keith, and Dave all
made the same mistakes. They placed a switch capable of shutting down the
engine in the wrong area of the instrument panel. End of story? NO!
As soon as one of these ECU suppliers
adds the "Are you sure?" logic, then all of these failures disappear.
Pretty simple logic statement. Actually, there are a whole bunch of ways this
can be handled. I had to do this type of programming with industrial plc's
because these same "oops" were so common. Think about this. If engine
has been running for more than 5 minutes, only allow small mixture changes.
Never enough to shut down engine. So let's say that 100 will shut down engine,
then we only allow a change of 20 each minute.
I think the ECU providers recognize
builder error. "Whew! Not MY problem." They don't ask: "Is
there something I can do to save lives?" If they make these
simple changes, then every single plane is no longer sensitive to these common
"oops" scenarios. So yes, if Dave moves his switch, HE will be
safer. But if the ECU supplier makes this simple programming change, then every
single plane will be safer. Real world mistakes will no longer shut down the
engine.
I want these suppliers to be successful.
I want fewer plane crashes. But it's not going to happen unless you guys
(privately) encourage these simple changes.
This group is making good progress on
failure reduction. There are a handful of ecu changes that will really make a
difference. Please pursue! Question question question.
----- Original Message -----
Sent: Sunday, March 14, 2010 7:10 AM
Subject: [FlyRotary] Re: Ut-Oh...
I know Dave
or Jon wouldn't phrase it this way but I've already received a number of
messages from others about these two recent in-flight power failures due to EC2
issues.
Jon's was due to a loose mounting nut inside the EC2 that shorted the
main power input filter to ground and burned open both foils from the 2 power
input pins. How lucky was that.
Anyway, at the risk of sounding defensive, I thought I'd share my
response to one of them that suggested changing the EC2 case to an external
mount of some sort. I'm sure there are scores of messages on the way
urging me to place switch guards on the cold start switch : )
REPLY
Hello ----------
I'm aware of the failure and have the unit here for repair.
Like a thousand other critical details in building an aircraft, it
is not possible to explicitly spell out all of them. The precise method
and hardware used to accomplish it are not part of the EC2 or the instructions.
The first paragraph of the installation guide does say the following:
"Needless to say, the quality of installation is just as important as the
quality of the hardware itself. It is not practical to include a course
on proper electrical wiring practices in these installation instructions, but
it is imperative that proper wiring techniques be employed during the
installation of the EC2."
It was my thought that avoiding the presence of loose metal objects inside an
electrical device that your life depends on fell into the category of
"needless to say".
Nevertheless, a cautionary note might well be worth adding. As also
stated in the first paragraph of the instructions,
" I want your project to succeed and your life to be a long and happy one.
"
--
David Leonard
Turbo Rotary RV-6 N4VY
http://N4VY.RotaryRoster.net
http://RotaryRoster.net
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