Today's Message Index:
----------------------
1. 05:22 AM - Re: Re: P Mags (Robert L. Nuckolls, III)
2. 05:25 AM - Re: P Mags (Stucklen, Frederic W UTPWR)
3. 06:39 AM - Re: P-mags (Hinde, Frank George (Corvallis))
4. 06:45 AM - Re: Re: P Mags (Hinde, Frank George (Corvallis))
5. 07:04 AM - Re: Re: P Mags (Hinde, Frank George (Corvallis))
6. 07:20 AM - Re: Poor man's DAS (David M.)
7. 07:28 AM - Re: P-mags and the RV-7 Off Field Landing (Darwin N. Barrie)
8. 07:46 AM - Re: Re: P Mags (Mike)
9. 07:47 AM - Re: Re: P Mags (Dave N6030X)
10. 08:40 AM - Re: Battery Charging (Ernest Christley)
11. 08:58 AM - JS-AIR Strobe Power pack with Whelen fixtures (Jeff)
12. 09:04 AM - Magneto failure in general, Was: Re: P Mags (BobsV35B@aol.com)
13. 09:52 AM - Re: Re: P Mags (Robert L. Nuckolls, III)
14. 10:03 AM - Re: Magneto failure in general, Was: Re: P Mags (Kevin Horton)
15. 10:03 AM - Re: JS-AIR Strobe Power pack with Whelen fixtures (JOHN TIPTON)
16. 10:03 AM - Re: Re: P Mags (Robert L. Nuckolls, III)
17. 10:13 AM - Re: Magneto failure in general, Was: Re: P Mags (Matt Prather)
18. 10:54 AM - Magneto failure in general, Was: Re: P Mags (BobsV35B@aol.com)
19. 11:01 AM - Magneto failure in general, Was: Re: P Mags (BobsV35B@aol.com)
20. 11:12 AM - Re: Magneto failure in general, Was: Re: P Mags (BobsV35B@aol.com)
21. 11:13 AM - Re: Re: P Mags (Hinde, Frank George (Corvallis))
22. 11:34 AM - mags / EIS debate (Charlie England)
23. 12:05 PM - Re: Magneto failure in general, Was: Re: P Mags (Matt Prather)
24. 12:39 PM - Re: Magneto failure in general, Was: Re: P Mags (Kevin Horton)
25. 12:40 PM - P Mags (James H Nelson)
26. 12:41 PM - Re: Re: P Mags (BobsV35B@aol.com)
27. 01:24 PM - Re: P Mags (Harley)
28. 01:29 PM - Re: Magneto failure in general, Was: Re: P Mags (Robert L. Nuckolls, III)
29. 01:30 PM - Re: Magneto failure in general, Was: Re: P Mags (Robert L. Nuckolls, III)
30. 01:31 PM - Re: Re: P Mags (Hinde, Frank George (Corvallis))
31. 02:21 PM - Re: Magneto failure in general, Was: Re: P Mags (Matt Prather)
32. 03:15 PM - JS-AIR Strobe Power pack with Whelen fixtures (Jeff)
33. 03:55 PM - Re: JS-AIR Strobe Power pack with Whelen fixtures (Neil Clayton)
34. 03:59 PM - Re: Magneto failure in general, Was: Re: P Mags (Deems Herring)
35. 04:01 PM - Re: JS-AIR Strobe Power pack with Whelen fixtures (robertbuls@aol.com)
36. 04:39 PM - Re: Magneto failure in general, Was: Re: P Mags (Matt Prather)
37. 05:17 PM - Re: Magneto failure in general, Was: Re: P Mags (Deems Herring)
38. 05:32 PM - Re: Magneto failure in general, Was: Re: P Mags (Michel Creek)
39. 05:43 PM - Re: P-mags and the RV-7 Off Field Landing (Bill Schlatterer)
40. 06:35 PM - Connecting to heated pitot tube (Dr. Andrew Elliott)
41. 07:49 PM - P Mags (James H Nelson)
42. 08:35 PM - Re: Battery Charging - CTEK XS3600 (Carl Morgan)
Message 1
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At 01:27 AM 2/22/2007 -0500, you wrote:
>The initial info I have is that one P Mag advanced the timing too far
>resulting in power loss since the fuel/air mixture was ignited as in
>entered the cylinder. During a power loss, the pilot should cycle the
>ignition source to left/right/both to check for any improvement.
Makes sense . . .
>The P Mags don't revert to the internal generator until electrical power
>is lost. Since electrical power was available, a P Mag would not revert
>to the backup mode, so that means when the faulty ignition is turned off,
>the engine would run normally again.
Hmmmm . . . whether or not ship's power is present,
placing the P-Mag switch in the OFF position should
shut it down.
>Initial indications are the pilot did not cycle the ignitions through
>left/right.
>I will be interesting to see what Brad discovers.
As will we all. Thanks!
A client and I have discussed making a trip to
Dallas/Ft.Worth area to visit both Plane Power
and Emagair. I'm hoping to forge some good lines
of communication with both of these companies
with a goal of providing accurate, filtered-for-
sensibility data should either of these folks
encounter a pot-hole in the road.
Bob . . .
Message 2
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Interesting problem... EMAG does have a service bulletin out on their
latest software change.
See http://emagair.com/Service%20Notes.htm This is for software updates
that occurred
between 12/06 and 2/07, and it involves how the engine timing is set
while in the setup mode.
I'm not sure if it would effect timing during normal engine operation,
unless the power to the
PMAGS was cycled in flight. Then it's perceivable that the timing could
have been changed.
Of course, this is all conjecture until all the facts are learned......
Fred Stucklen
RV-6A N925RV 720 Hrs
Two PMAGS
Subject: Re: P Mags
From:
<mailto:Speedy11@aol.com?subject=Re:%20P%20Mags&replyto=d44.25c73b2.3
30e
91cb@aol.com> Speedy11@aol.com
<mailto:Speedy11@aol.com?subject=Re:%20P%20Mags&replyto=d44.25c73b2.3
30e
91cb@aol.com>
Date: Wed Feb 21 - 10:29 PM
The initial info I have is that one P Mag advanced the timing
too far
resulting in power loss since the fuel/air mixture was ignited
as in entered the
cylinder. During a power loss, the pilot should cycle the
ignition source to
left/right/both to check for any improvement. The P Mags don't
revert to the
internal generator until electrical power is lost. Since
electrical power was
available, a P Mag would not revert to the backup mode, so that
means when the
faulty ignition is turned off, the engine would run normally
again. Initial
indications are the pilot did not cycle the ignitions through
left/right.
I will be interesting to see what Brad discovers.
Stan Sutterfield
Message 3
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Yes and in my head at least I intend to do this...I must say it did
occur to me (briefly) but I was close to being overwhelmed as I was
approaching a fog bank that I had to make an ILS approach through...It
was 400ft ceiling so I knew we could make it but it takes some nerve to
shut down a mag in that situation, bearing in mind I really had no idea
what was happening at the time. Excuses excuses..:)
With hindsight, yes just shut down a mag, does it get better? NO,
re-enable and shutdown the other one.
Cheers
Frank
-----Original Message-----
From: owner-aeroelectric-list-server@matronics.com
[mailto:owner-aeroelectric-list-server@matronics.com] On Behalf Of
Robert L. Nuckolls, III
Sent: Wednesday, February 21, 2007 8:09 PM
Subject: RE: AeroElectric-List: P-mags
--> <nuckollsr@cox.net>
At 02:49 PM 2/21/2007 +0000, you wrote:
(Corvallis)"
><frank.hinde@hp.com>
>
>Fair point Harry,
>
>I guess my conjecture was that one of the P mags could have been turned
>off and the engine would have resumed normal operation...I just wish
>I'd though of it when it happened to me...Of course my engine just ran
>hot, i.e did not causean engine stoppage.
>
>Frank
Since this is a failure mode unique to the e/p-mag
products, perhaps words to guide the pilot in conducting
an in-flight diagnosis and remedy should be added to
the POH for any aircraft that carries one or more
Emagair products.
Bob . . .
Message 4
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Well he didn't discover anything wrong with mine...Darn those
intermittent faults...:)
Not quite sure I understand what your saying Stan.... When we say cycle
the E/Pmags we mean to ground the P lead...I.e the mag that is turned
off will stop firing. You mention removing the power to the Pmag but
that will do nothing to stop the Pmag firing because as you say the
backup alt will continue to make sparks.
In order to fault find which P/emag has gone whacko you have to stop
each one form working to see if the situation gets better...i.e ground
the P lead.
Frank
________________________________
From: owner-aeroelectric-list-server@matronics.com
[mailto:owner-aeroelectric-list-server@matronics.com] On Behalf Of
Speedy11@aol.com
Sent: Wednesday, February 21, 2007 10:27 PM
Subject: AeroElectric-List: Re: P Mags
The initial info I have is that one P Mag advanced the timing too far
resulting in power loss since the fuel/air mixture was ignited as in
entered the cylinder. During a power loss, the pilot should cycle the
ignition source to left/right/both to check for any improvement. The P
Mags don't revert to the internal generator until electrical power is
lost. Since electrical power was available, a P Mag would not revert to
the backup mode, so that means when the faulty ignition is turned off,
the engine would run normally again. Initial indications are the pilot
did not cycle the ignitions through left/right.
I will be interesting to see what Brad discovers.
Stan Sutterfield
Nope Dual P mags. They did NOT fail. I believe ONE of them went
to very
advanced timing. It has the effect of fouling up the timing
completely
because once the charge has been lit the second spark doesn't do
anything.
________________________________
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Message 5
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Yes, OFF being the Plead is grounded.
I certainly would not advocate trying to put the E/pmag in test mode in
flight, too complex and to lengthy to think through.
All you need to do is shut one unit down hard..I.e ground the P
lead...If it gets better great, if not simply repeat in the other
e/pmag.
I have a small bone of contention with the most recent incident. The
story goes the timing was so advanced the charge simply puffed thru the
open exhaust valve, implying this is a relatively harmless event. In my
reading of the effects of excessively advanced timing it seems this can
be very destructive pre-ignition. Remember that I and our friend saw
very high oil temps and CHT's. According to my reading of some of the
maintenance articles published by engine shops, preignition is caused by
the charge being ignited while the piston is still travelling UP the
bore. The piston then has to compress the rapidly expanding (and hot)
charge.
Apparently the very high cylinder pressures can then force this hot
charge past the rings and heat the oil directly. It also adds
considerable stress to the bottom end bearings.
As you can see from the above description this stuation can be very
destructive. I didn't want folks to think this was a relatively harmless
situation as it could (from what has been explained to me) destroy the
engine in short order.
I have yet to do an oil anaylisis which I hope will show no abnormal
levels.
Frank
-----Original Message-----
From: owner-aeroelectric-list-server@matronics.com
[mailto:owner-aeroelectric-list-server@matronics.com] On Behalf Of
Robert L. Nuckolls, III
Sent: Thursday, February 22, 2007 5:19 AM
Subject: Re: AeroElectric-List: Re: P Mags
--> <nuckollsr@cox.net>
At 01:27 AM 2/22/2007 -0500, you wrote:
>The initial info I have is that one P Mag advanced the timing too far
>resulting in power loss since the fuel/air mixture was ignited as in
>entered the cylinder. During a power loss, the pilot should cycle the
>ignition source to left/right/both to check for any improvement.
Makes sense . . .
>The P Mags don't revert to the internal generator until electrical
>power is lost. Since electrical power was available, a P Mag would not
>revert to the backup mode, so that means when the faulty ignition is
>turned off, the engine would run normally again.
Hmmmm . . . whether or not ship's power is present,
placing the P-Mag switch in the OFF position should
shut it down.
>Initial indications are the pilot did not cycle the ignitions through
>left/right.
>I will be interesting to see what Brad discovers.
As will we all. Thanks!
A client and I have discussed making a trip to
Dallas/Ft.Worth area to visit both Plane Power
and Emagair. I'm hoping to forge some good lines
of communication with both of these companies
with a goal of providing accurate, filtered-for-
sensibility data should either of these folks
encounter a pot-hole in the road.
Bob . . .
Message 6
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| Subject: | Re: Poor man's DAS |
John, my plans are similar to yours. Good luck with them.
I've had a labjack U12 for many years now and may have found a better
alternative. Go to some of the Freescale (Motorola) processor seminars
where the price includes a test board. You're more into the design
phase during implementation but you can keep costs in the under $10
range if you like. The downside is that even though CodeWarrior lite
comes 'free' during the seminar,it is ATROCIOUS as a development
environment.
David M.
----- Original Message -----
From: John and Kim Lumkes
To: aeroelectric-list@matronics.com
Sent: Thursday, February 15, 2007 2:11 PM
Subject: Re: AeroElectric-List: Poor man's DAS
I can personally vouch for the Labjack series. I have purchased and
installed approximately 25 units in a teaching laboratory; no matter how
many mistakes the student made, only one unit ever failed and the
factory replaced it at no charge. I now use them again at my "new"
position, and have my own personal one at home. I have used it to record
data around the house (temp's, flow, etc.) and plan on installing one in
the airplane with a mini-ITX PC to have my own data logger / EIS. The
interface can easily be done in Labview, and having the "carpc" will
also allow me to run PocketFMS on a split screen. This is definitely
"experimental" and so all required gauges will also be "steam wired".
There so many ICs now like thermocouple amplifiers with built in cold
junctions, small economical pressure transducers, etc., that adding
features are easier now than ever before for amateur electrical system
integrators (like myself).
Long term plans: adding solid state gyros (IC chips now have this
ability) for AHRS and wing leveling / GPS based auto-pilot.
John
-------------------------------------------------------------------------
-----
2/10/2007 9:15 PM
Message 7
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| Subject: | Re: P-mags and the RV-7 Off Field Landing |
The gentleman this happened to is a good friend. I received the call
that he has went down and all was safe.
I also have dual Pmags on my plane and have had no problems at all in
185 hours. After he was home safe, I asked him if he had switched
between Mags to see if he could isolate the problem. He did not and said
he didn't think of it.
I agree that the chance of both failing is very slim. Switching each mag
off individually should be part of your check list if a problem arrises.
I personally don't power them off on ground run but only do the L/R/Both
checks.
As Bob said don't paint Emagair with such a wide brush. These guys are
responsive to our needs and have never denied or made any effort to hide
an issue. I continue to have 100% confidence in this system. As with any
aspect of flying, it is critical to know what to do when something goes
wrong.
Darwin N. Barrie
Chandler AZ
RV7 N717EE
Message 8
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Frank is right again! The point he makes is as a very important. What
is the effect of an ignition system going off time? In this case and
the one I was involved with the P-mag appeared to go more advanced.
Pre-ignition in an aircraft engine is a very bad thing! So it seems
that the change in potential timing advance could be a bigger problem
then a strait forward failure. Going back to Kelly's position about
mags vs. CDI and the like, I believe this would be one for the mag pro
side of the page. Mind you, I run dual LSE Plasma III on one of my
airplanes and love it.
Mike Larkin
-----Original Message-----
From: owner-aeroelectric-list-server@matronics.com
[mailto:owner-aeroelectric-list-server@matronics.com] On Behalf Of
Hinde, Frank George (Corvallis)
Sent: Thursday, February 22, 2007 8:00 AM
Subject: RE: AeroElectric-List: Re: P Mags
(Corvallis)" <frank.hinde@hp.com>
Yes, OFF being the Plead is grounded.
I certainly would not advocate trying to put the E/pmag in test mode in
flight, too complex and to lengthy to think through.
All you need to do is shut one unit down hard..I.e ground the P
lead...If it gets better great, if not simply repeat in the other
e/pmag.
I have a small bone of contention with the most recent incident. The
story goes the timing was so advanced the charge simply puffed thru the
open exhaust valve, implying this is a relatively harmless event. In my
reading of the effects of excessively advanced timing it seems this can
be very destructive pre-ignition. Remember that I and our friend saw
very high oil temps and CHT's. According to my reading of some of the
maintenance articles published by engine shops, preignition is caused by
the charge being ignited while the piston is still travelling UP the
bore. The piston then has to compress the rapidly expanding (and hot)
charge.
Apparently the very high cylinder pressures can then force this hot
charge past the rings and heat the oil directly. It also adds
considerable stress to the bottom end bearings.
As you can see from the above description this stuation can be very
destructive. I didn't want folks to think this was a relatively harmless
situation as it could (from what has been explained to me) destroy the
engine in short order.
I have yet to do an oil anaylisis which I hope will show no abnormal
levels.
Frank
-----Original Message-----
From: owner-aeroelectric-list-server@matronics.com
[mailto:owner-aeroelectric-list-server@matronics.com] On Behalf Of
Robert L. Nuckolls, III
Sent: Thursday, February 22, 2007 5:19 AM
Subject: Re: AeroElectric-List: Re: P Mags
--> <nuckollsr@cox.net>
At 01:27 AM 2/22/2007 -0500, you wrote:
>The initial info I have is that one P Mag advanced the timing too far
>resulting in power loss since the fuel/air mixture was ignited as in
>entered the cylinder. During a power loss, the pilot should cycle the
>ignition source to left/right/both to check for any improvement.
Makes sense . . .
>The P Mags don't revert to the internal generator until electrical
>power is lost. Since electrical power was available, a P Mag would not
>revert to the backup mode, so that means when the faulty ignition is
>turned off, the engine would run normally again.
Hmmmm . . . whether or not ship's power is present,
placing the P-Mag switch in the OFF position should
shut it down.
>Initial indications are the pilot did not cycle the ignitions through
>left/right.
>I will be interesting to see what Brad discovers.
As will we all. Thanks!
A client and I have discussed making a trip to
Dallas/Ft.Worth area to visit both Plane Power
and Emagair. I'm hoping to forge some good lines
of communication with both of these companies
with a goal of providing accurate, filtered-for-
sensibility data should either of these folks
encounter a pot-hole in the road.
Bob . . .
--
2/8/2007
--
2/8/2007
Message 9
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Yes, I believe the latest word we have from the engine experts is
that the destructive effects we have always blamed on "detonation"
are actually caused by "preignition", the latter being the one that
punches holes in pistons and generally destroys the engine in short
order. Whereas "detonation" actually occurs in a broad range from
"mild" to "severe" with the milder end having no ill effects on the engine.
For reference: http://www.avweb.com/news/pelican/194452-1.html
Dave Morris
At 08:59 AM 2/22/2007, you wrote:
>(Corvallis)" <frank.hinde@hp.com>
>
>
>I have a small bone of contention with the most recent incident. The
>story goes the timing was so advanced the charge simply puffed thru the
>open exhaust valve, implying this is a relatively harmless event. In my
>reading of the effects of excessively advanced timing it seems this can
>be very destructive pre-ignition. Remember that I and our friend saw
>very high oil temps and CHT's. According to my reading of some of the
>maintenance articles published by engine shops, preignition is caused by
>the charge being ignited while the piston is still travelling UP the
>bore. The piston then has to compress the rapidly expanding (and hot)
>charge.
>
>Apparently the very high cylinder pressures can then force this hot
>charge past the rings and heat the oil directly. It also adds
>considerable stress to the bottom end bearings.
>
>As you can see from the above description this stuation can be very
>destructive. I didn't want folks to think this was a relatively harmless
>situation as it could (from what has been explained to me) destroy the
>engine in short order.
>
>I have yet to do an oil anaylisis which I hope will show no abnormal
>levels.
>
>Frank
Message 10
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| Subject: | Re: Battery Charging |
CH701 wrote:
>
>Speaking of battery charging, a recent issue of Sport Aviation had an
>article entitled "Pulse De-sulfator for Lead-acid Batteries." It described
>the process of resurrecting weak or sulfated batteries, and included some
>theory and a schematic of a circuit to address the process. I'm just
>wondering what this community has to offer on the subject...
>
>Here's a link to the authors site:
>http://www.geocities.com/powertugs/eaa79parts.html
>
>
I wanted to make a Frankenstein combination of this circuit and one that
Jim Weir laid out in a recent Kitplanes article for using a solar cell
to charge the battery. Basically, I would insert the desulfator in the
circuit where the green "charged" LED indicator would be in Jim's
circuit. The idea was that once the battery was fully charged, the
desulfating would be enough to keep it topped off and completely healthy.
After some investigation, I gave up. The deal breaker was that the
desulfator uses upwards of a 60V pulse. There would be no way short of
a disconnected master of isolating the pulse from the rest of the
airplane (and electronics that may not care for 60V pulses). I decided
that I didn't want 60V pulses around my 12V system at all. It's what I
call "setting a trap for myself", which I have a habit of doing
accidently, so I try to avoid doing it on purpose.
--
,|"|"|, Ernest Christley |
----===<{{(oQo)}}>===---- Dyke Delta Builder |
o| d |o http://ernest.isa-geek.org |
Message 11
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| Subject: | JS-AIR Strobe Power pack with Whelen fixtures |
Does anyone have experience using the JS-AIR XPAK 604-HR power pack with the
Whelan A650 position/strobe light fixtures? The JS-AIR is considerably
cheaper and uses less amperage that the Whelen power pack.
Jeff Davidson
Message 12
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Good Morning Mike
My following comments do NOT mean I dislike magnetos, but if you have an
impulse magneto and the spring on the impulse fails, the same problem can occur.
That is one of the reasons that most good instructors teach that each
magneto should be shut down independently any time an engine gets rough. There
are
other internal failure modes that will do the same thing.
I have had the plastic gear strip and have had springs break.
Switching the bad magneto off put the engine back to running normally.
In some ways the very reliability of modern ignition systems has set us up
to not recognize failures when they occur. Sixty years ago, magneto failures
of that sort were common.
One more good idea is to make a magneto check just before landing. That
check will be more meaningful if it is done at a fairly high cruise power
setting. Such a check is much more likely to catch a magneto, spark plug, or a
harness, that is getting marginal than is the low power check we do just before
takeoff.
I would certainly not consider the failure mode of the E-Mag to be any worse
than failure modes that are common with any magneto.
Happy Skies,
Old Bob
AKA
Bob Siegfried
Ancient Aviator
Stearman N3977A
Brookeridge Air Park LL22
Downers Grove, IL 60516
630 985-8503
In a message dated 2/22/2007 9:50:39 A.M. Central Standard Time,
mlas@cox.net writes:
Frank is right again! The point he makes is as a very important. What
is the effect of an ignition system going off time? In this case and
the one I was involved with the P-mag appeared to go more advanced.
Pre-ignition in an aircraft engine is a very bad thing! So it seems
that the change in potential timing advance could be a bigger problem
then a strait forward failure. Going back to Kelly's position about
mags vs. CDI and the like, I believe this would be one for the mag pro
side of the page. Mind you, I run dual LSE Plasma III on one of my
airplanes and love it.
Mike Larkin
<BR><BR><BR>**************************************<BR> AOL now offers free
email to everyone. Find out more about what's free from AOL at
http://www.aol.com.
Message 13
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At 08:22 AM 2/22/2007 -0500, you wrote:
>Interesting problem... EMAG does have a service bulletin out on their
>latest software change.
>See
><http://emagair.com/Service%20Notes.htm>http://emagair.com/Service%20Notes.htm
>This is for software updates that occurred
>between 12/06 and 2/07, and it involves how the engine timing is set while
>in the setup mode.
>I'm not sure if it would effect timing during normal engine operation,
>unless the power to the
>PMAGS was cycled in flight. Then it's perceivable that the timing could
>have been changed.
>Of course, this is all conjecture until all the facts are learned......
Drop them a note and ask. When in doubt, talk to the
"horse" . . .
Bob . . .
----------------------------------------
( IF one aspires to be "world class", )
( what ever you do must be exercised )
( EVERY day . . . )
( R. L. Nuckolls III )
----------------------------------------
Message 14
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On 22 Feb 2007, at 12:01, BobsV35B@aol.com wrote:
> I would certainly not consider the failure mode of the E-Mag to be
> any worse than failure modes that are common with any magneto.
>
The failure mode that is described in the E-Mag service bulletin
could affect both ignitions at once, if one had two E-Mag ignition
systems installed. The failure mode occurs when the system
incorrectly uses negative MP pulses to trigger the timing Quick-Set
mode. The system is supposed to only sense positive pressure MP
pulses, but due to a software problem, it will also sense negative
pressure MP pulses. Both ignition systems likely see the same MP
pulses, so both ignitions could have their timing changed. There are
other protections that were intended to ensure that the Quick-Set
mode could not be triggered in flight, but there are things the pilot
may do in normal operation that could invalidate those protections.
http://emagair.com/E-MAG%20Service%20Bulletin1.pdf
I'm not aware of any magneto failure modes where one event could
trigger both mags to fail at the same time.
Kevin Horton
RV-8 (Finishing Kit)
Ottawa, Canada
http://www.kilohotel.com/rv8
Message 15
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| Subject: | Re: JS-AIR Strobe Power pack with Whelen fixtures |
Who, What ???
----- Original Message -----
From: "Jeff " <jeffrey_davidson@earthlink.net>
Sent: Thursday, February 22, 2007 4:54 PM
Subject: AeroElectric-List: JS-AIR Strobe Power pack with Whelen fixtures
> <jeffrey_davidson@earthlink.net>
>
> Does anyone have experience using the JS-AIR XPAK 604-HR power pack with
> the
> Whelan A650 position/strobe light fixtures? The JS-AIR is considerably
> cheaper and uses less amperage that the Whelen power pack.
> Jeff Davidson
>
>
>
Message 16
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At 02:59 PM 2/22/2007 +0000, you wrote:
><frank.hinde@hp.com>
>
>Yes, OFF being the Plead is grounded.
>
>I certainly would not advocate trying to put the E/pmag in test mode in
>flight, too complex and to lengthy to think through.
How does one do this? Perhaps I'm behind the
curve on this but I thought that powering up
a Emagair product with the p-lead grounded offered
the mechanic a built in "buzzer" used to
set the mechanical timing. Are there "test"
functions beyond this capability?
>All you need to do is shut one unit down hard..I.e ground the P
>lead...If it gets better great, if not simply repeat in the other
>e/pmag.
>
>I have a small bone of contention with the most recent incident. The
>story goes the timing was so advanced the charge simply puffed thru the
>open exhaust valve, implying this is a relatively harmless event. In my
>reading of the effects of excessively advanced timing it seems this can
>be very destructive pre-ignition. Remember that I and our friend saw
>very high oil temps and CHT's. According to my reading of some of the
>maintenance articles published by engine shops, preignition is caused by
>the charge being ignited while the piston is still travelling UP the
>bore. The piston then has to compress the rapidly expanding (and hot)
>charge.
If someone observes high temps . . . then this implies
that the condition existed for some period of time.
From onset of a problem to the time that any temperature
becomes "high" has to be on the order of minutes.
The image painted by these words suggests a sort of
mental paralysis . . . the fact that the pilot chose
an off-field landing further suggests that he didn't
have a good understanding of how his equipment worked
nor did he have a "plan" for dealing with things that
have proven to be in-flight diagnosed and dealt with
toward the goal of a happy ending.
>Apparently the very high cylinder pressures can then force this hot
>charge past the rings and heat the oil directly. It also adds
>considerable stress to the bottom end bearings.
Higher than those pressures/stresses that occur when timing
is optimized for maximum realization of available
energy from the fuel?
>As you can see from the above description this stuation can be very
>destructive. I didn't want folks to think this was a relatively harmless
>situation as it could (from what has been explained to me) destroy the
>engine in short order.
I'm not sure that the combustion physics teamed
with knowledge of the strengths of engine components
and stresses encountered in NORMAL operations
support the notion that the engine is mechanically
at risk for the hypothesized failure.
George Braley - are you watching this thread? Can you help
with a dissertation on the underlying simple-ideas?
Bob . . .
Message 17
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Hello Bob,
I have read/been-told that cycling the mag switch while at high power
settings might cause the engine to backfire if one mag is dead and the
other is turned back on, and that such a backfire might damage components
of the intake and exhaust systems.. What do you think about this?
Matt-
>
>
> Good Morning Mike
>
> My following comments do NOT mean I dislike magnetos, but if you have an
> impulse magneto and the spring on the impulse fails, the same problem can
> occur.
>
> That is one of the reasons that most good instructors teach that each
> magneto should be shut down independently any time an engine gets rough.
> There are
> other internal failure modes that will do the same thing.
>
> I have had the plastic gear strip and have had springs break.
>
> Switching the bad magneto off put the engine back to running normally.
>
> In some ways the very reliability of modern ignition systems has set us
> up
> to not recognize failures when they occur. Sixty years ago, magneto
> failures
> of that sort were common.
>
> One more good idea is to make a magneto check just before landing. That
> check will be more meaningful if it is done at a fairly high cruise power
> setting. Such a check is much more likely to catch a magneto, spark plug,
> or a
> harness, that is getting marginal than is the low power check we do just
> before
> takeoff.
>
> I would certainly not consider the failure mode of the E-Mag to be any
> worse
> than failure modes that are common with any magneto.
>
> Happy Skies,
>
> Old Bob
> AKA
> Bob Siegfried
> Ancient Aviator
> Stearman N3977A
> Brookeridge Air Park LL22
> Downers Grove, IL 60516
> 630 985-8503
>
>
> In a message dated 2/22/2007 9:50:39 A.M. Central Standard Time,
> mlas@cox.net writes:
>
> Frank is right again! The point he makes is as a very important. What
> is the effect of an ignition system going off time? In this case and
> the one I was involved with the P-mag appeared to go more advanced.
> Pre-ignition in an aircraft engine is a very bad thing! So it seems
> that the change in potential timing advance could be a bigger problem
> then a strait forward failure. Going back to Kelly's position about
> mags vs. CDI and the like, I believe this would be one for the mag pro
> side of the page. Mind you, I run dual LSE Plasma III on one of my
> airplanes and love it.
>
> Mike Larkin
>
>
> <BR><BR><BR>**************************************<BR> AOL now offers free
> email to everyone. Find out more about what's free from AOL at
> http://www.aol.com.
>
Message 18
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Good Afternoon Matt,
The procedure, as taught, is to be very sure you DO NOT turn on the
remaining good magneto if the engine does quit. The drill then is to put the mixture
in full lean, count to ten, turn on the magneto and slowly richen the mixture
until the engine starts.
I have never had it happen that way and I am sure it will take a lot of
discipline to wait those few seconds for the engine to clear itself before the
magneto is placed back in service!
It does help if the operator has experience deliberately running fuel tanks
dry.
That procedure is another one that is rarely taught these days, but having
run a tank dry often does instill confidence in the restart procedure.
Happy Skies,
Old Bob
AKA
Bob Siegfried
Ancient Aviator
Stearman N3977A
Brookeridge Air Park LL22
Downers Grove, IL 60516
630 985-8503
In a message dated 2/22/2007 12:16:43 P.M. Central Standard Time,
mprather@spro.net writes:
I have read/been-told that cycling the mag switch while at high power
settings might cause the engine to backfire if one mag is dead and the
other is turned back on, and that such a backfire might damage components
of the intake and exhaust systems.. What do you think about this?
Matt-
<BR><BR><BR>**************************************<BR> AOL now offers free
email to everyone. Find out more about what's free from AOL at
http://www.aol.com.
Message 19
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Good Afternoon Ken,
Well, as long as we are discussing potential multiple failures or single
point failures, what happens when the drive gear on a dual magneto fails?
In any case, I meant to be responding to the potential of getting a magneto
out of time as happened on the flight being discussed.
The Service Bulletin was not what I had in mind, but anything made by man is
subject to some sort of failure mode.
Happy Skies,
Old Bob
AKA
Bob Siegfried
Ancient Aviator
Stearman N3977A
Brookeridge Air Park LL22
Downers Grove, IL 60516
630 985-8503
In a message dated 2/22/2007 12:05:56 P.M. Central Standard Time,
khorton01@rogers.com writes:
On 22 Feb 2007, at 12:01, _BobsV35B@aol.com_ (mailto:BobsV35B@aol.com) wrote:
I would certainly not consider the failure mode of the E-Mag to be any worse
than failure modes that are common with any magneto.
The failure mode that is described in the E-Mag service bulletin could
affect both ignitions at once, if one had two E-Mag ignition systems installed.
The failure mode occurs when the system incorrectly uses negative MP pulses to
trigger the timing Quick-Set mode. The system is supposed to only sense
positive pressure MP pulses, but due to a software problem, it will also sense
negative pressure MP pulses. Both ignition systems likely see the same MP
pulses, so both ignitions could have their timing changed. There are other
protections that were intended to ensure that the Quick-Set mode could not be
triggered in flight, but there are things the pilot may do in normal operation
that could invalidate those protections.
_http://emagair.com/E-MAG%20Service%20Bulletin1.pdf_
(http://emagair.com/E-MAG%20Service%20Bulletin1.pdf)
I'm not aware of any magneto failure modes where one event could trigger
both mags to fail at the same time.
Kevin Horton
RV-8 (Finishing Kit)
Ottawa, Canada
_http://www.kilohotel.com/rv8_ (http://www.kilohotel.com/rv8)
<BR><BR><BR>**************************************<BR> AOL now offers free
email to everyone. Find out more about what's free from AOL at
http://www.aol.com.
Message 20
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In a message dated 2/22/2007 1:05:51 P.M. Central Standard Time,
BobsV35B@aol.com writes:
Good Afternoon Ken,
OOOPs!! should have been:
Good Afternoon Kevin,
Sorry about that.
Do Not Archive
Happy Skies,
Old Bob
AKA
Bob Siegfried
Ancient Aviator
Stearman N3977A
Brookeridge Air Park LL22
Downers Grove, IL 60516
630 985-8503
<BR><BR><BR>**************************************<BR> AOL now offers free
email to everyone. Find out more about what's free from AOL at
http://www.aol.com.
Message 21
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How does one do this? Perhaps I'm behind the
curve on this but I thought that powering up
a Emagair product with the p-lead grounded offered
the mechanic a built in "buzzer" used to
set the mechanical timing. Are there "test"
functions beyond this capability?
Nope I think you got it right there Bob...In theory you could do this in
flight which is what I thought a previous lister was prosing.
>All you need to do is shut one unit down hard..I.e ground the P
>lead...If it gets better great, if not simply repeat in the other
>e/pmag.
>
>I have a small bone of contention with the most recent incident. The
>story goes the timing was so advanced the charge simply puffed thru the
>open exhaust valve, implying this is a relatively harmless event. In my
>reading of the effects of excessively advanced timing it seems this can
>be very destructive pre-ignition. Remember that I and our friend saw
>very high oil temps and CHT's. According to my reading of some of the
>maintenance articles published by engine shops, preignition is caused
>by the charge being ignited while the piston is still travelling UP the
>bore. The piston then has to compress the rapidly expanding (and hot)
>charge.
If someone observes high temps . . . then this implies
that the condition existed for some period of time.
From onset of a problem to the time that any temperature
becomes "high" has to be on the order of minutes.
Depends when you Notice the problem...Yes it is minutes, but you also
have to connect high CHT's to a timing problem...I didn't
The image painted by these words suggests a sort of
mental paralysis . . . the fact that the pilot chose
an off-field landing further suggests that he didn't
have a good understanding of how his equipment worked
nor did he have a "plan" for dealing with things that
have proven to be in-flight diagnosed and dealt with
toward the goal of a happy ending.
Mental paralysis?.....I'm a MECHANICAL engineer...we don't have
those...:). As I said you had to connect high temps to wobbly timing. In
my case the engine was running perfectly, just showing whacko temps...As
all the temps were measured by the Dynon EMS I was a first almost
convinced it was a Dynon grounding issue, I.e not a problem at all.
>Apparently the very high cylinder pressures can then force this hot
>charge past the rings and heat the oil directly. It also adds
>considerable stress to the bottom end bearings.
Higher than those pressures/stresses that occur when timing
is optimized for maximum realization of available
energy from the fuel?
No but the piston is already on the way down...i.e the peak pressure may
be the same but it is reducing rapidly...We know that blowby always
happens, but in a pre-igniton situation it happens for much longer,
therefore more blowby and direct heating of the oil.
At least this is how it was explained to me...I am not an expert on
preignition by any streatch.
>As you can see from the above description this stuation can be very
>destructive. I didn't want folks to think this was a relatively
>harmless situation as it could (from what has been explained to me)
>destroy the engine in short order.
I'm not sure that the combustion physics teamed
with knowledge of the strengths of engine components
and stresses encountered in NORMAL operations
support the notion that the engine is mechanically
at risk for the hypothesized failure.
George Braley - are you watching this thread? Can you help
with a dissertation on the underlying simple-ideas?
Yes inquiring mind most definatly want to know...:)
Bob . . .
_Frank
Message 22
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| Subject: | mags / EIS debate |
Interesting coincidence, posted on another list yesterday...
-------- Original Message --------
Subject: [ThorpList] Rough Engine
From: <hkaribian@yahoo.com>
My rough engine turned out to be mag coils. Started up and ran fine when
cold but after flying a while my electronic tach started jumping all
over the gage, and I mistakenly assumed instrument problems, until the
engine quit and put me down on a dirt road in the woods.
--
<pre><b><font size=2 color="#000000" face="courier new,courier">
</b></font></pre></body></html>
Message 23
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Aha... That clears it up for me. Thanks for the description of the
correct procedure. And, yes it would take some discipline to keep from
just turning the mag back on...
Regards,
Matt-
>
>
> Good Afternoon Matt,
>
> The procedure, as taught, is to be very sure you DO NOT turn on the
> remaining good magneto if the engine does quit. The drill then is to put
> the mixture
> in full lean, count to ten, turn on the magneto and slowly richen the
> mixture
> until the engine starts.
>
> I have never had it happen that way and I am sure it will take a lot of
> discipline to wait those few seconds for the engine to clear itself before
> the
> magneto is placed back in service!
>
> It does help if the operator has experience deliberately running fuel
> tanks
> dry.
>
> That procedure is another one that is rarely taught these days, but having
> run a tank dry often does instill confidence in the restart procedure.
>
> Happy Skies,
>
> Old Bob
> AKA
> Bob Siegfried
> Ancient Aviator
> Stearman N3977A
> Brookeridge Air Park LL22
> Downers Grove, IL 60516
> 630 985-8503
>
>
> In a message dated 2/22/2007 12:16:43 P.M. Central Standard Time,
> mprather@spro.net writes:
>
> I have read/been-told that cycling the mag switch while at high power
> settings might cause the engine to backfire if one mag is dead and the
> other is turned back on, and that such a backfire might damage components
> of the intake and exhaust systems.. What do you think about this?
>
>
> Matt-
>
>
> <BR><BR><BR>**************************************<BR> AOL now offers free
> email to everyone. Find out more about what's free from AOL at
> http://www.aol.com.
>
Message 24
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Bob,
I share your concern with dual drive magnetos, and would not want to
own an engine with such a beast.
Kevin Horton
On 22 Feb 2007, at 13:58, BobsV35B@aol.com wrote:
> Good Afternoon Ken,
>
> Well, as long as we are discussing potential multiple failures or
> single point failures, what happens when the drive gear on a dual
> magneto fails?
>
> In any case, I meant to be responding to the potential of getting a
> magneto out of time as happened on the flight being discussed.
>
> The Service Bulletin was not what I had in mind, but anything made
> by man is subject to some sort of failure mode.
>
> Happy Skies,
>
> Old Bob
> AKA
> Bob Siegfried
> Ancient Aviator
> Stearman N3977A
> Brookeridge Air Park LL22
> Downers Grove, IL 60516
> 630 985-8503
>
> In a message dated 2/22/2007 12:05:56 P.M. Central Standard Time,
> khorton01@rogers.com writes:
> On 22 Feb 2007, at 12:01, BobsV35B@aol.com wrote:
>
>> I would certainly not consider the failure mode of the E-Mag to be
>> any worse than failure modes that are common with any magneto.
>>
>
> The failure mode that is described in the E-Mag service bulletin
> could affect both ignitions at once, if one had two E-Mag ignition
> systems installed. The failure mode occurs when the system
> incorrectly uses negative MP pulses to trigger the timing Quick-Set
> mode. The system is supposed to only sense positive pressure MP
> pulses, but due to a software problem, it will also sense negative
> pressure MP pulses. Both ignition systems likely see the same MP
> pulses, so both ignitions could have their timing changed. There
> are other protections that were intended to ensure that the Quick-
> Set mode could not be triggered in flight, but there are things the
> pilot may do in normal operation that could invalidate those
> protections.
>
> http://emagair.com/E-MAG%20Service%20Bulletin1.pdf
>
> I'm not aware of any magneto failure modes where one event could
> trigger both mags to fail at the same time.
>
> Kevin Horton
> RV-8 (Finishing Kit)
> Ottawa, Canada
> http://www.kilohotel.com/rv8
Message 25
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Stan,
Brad has put out a service bulletin on the "E-Mags" to check for
the possibility of a "vacuum" caused timing change. These units were put
out in the last 90 days or so. His bulletin says to check the units by
trying to change the timing by sucking on the vac hoses rather than the
"pressure" method. I had my 'mags in for the latest software change so
they could have had the "wrong" software installed. I checked them out
last Sunday and they will not change the timing function no matter how
hoard I suck on the vac hose. I'm not sure this may have caused the
problem but worth the check out and having the latest software installed.
Jim
Message 26
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Good Afternoon Frank,
Actually, if the timing is advanced, the pressures and temperature can, and
probably will, be much higher than the pressures and temperatures developed
when the fire is lit at the proper point. Any time the peak pressure point gets
closer to TDC than ten or eleven degrees, the crank shaft has a LOT more
resistance and the pressure can be as high as twelve hundred to fifteen hundred
pounds whereas if the ignition event is properly timed the same engine may
never see a pressure above eight hundred pounds.
It can make a VERY big difference.
Happy Skies,
Old Bob
AKA
Bob Siegfried
Ancient Aviator
Stearman N3977A
Brookeridge Air Park LL22
Downers Grove, IL 60516
630 985-8503
In a message dated 2/22/2007 1:15:55 P.M. Central Standard Time,
frank.hinde@hp.com writes:
Higher than those pressures/stresses that occur when timing
is optimized for maximum realization of available
energy from the fuel?
<BR><BR><BR>**************************************<BR> AOL now offers free
email to everyone. Find out more about what's free from AOL at
http://www.aol.com.
Message 27
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Jim...
>>they will not change the timing function no matter how hoard I suck
on the vac hose.<<
Did you try TWO quick short "sucks", so to speak?<G> 0.5 psi or
greater? On reading the email I received from them, I interpreted it as
it takes two short pulses to change the setting.
Mine aren't installed yet, or I'd try it.
Harley
------------------------------------------------------------------------
James H Nelson wrote:
>
> Stan,
> Brad has put out a service bulletin on the "E-Mags" to check for
> the possibility of a "vacuum" caused timing change. These units were put
> out in the last 90 days or so. His bulletin says to check the units by
> trying to change the timing by sucking on the vac hoses rather than the
> "pressure" method. I had my 'mags in for the latest software change so
> they could have had the "wrong" software installed. I checked them out
> last Sunday and they will not change the timing function no matter how
> hoard I suck on the vac hose. I'm not sure this may have caused the
> problem but worth the check out and having the latest software installed.
>
> Jim
>
>
>
Message 28
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At 11:11 AM 2/22/2007 -0700, you wrote:
>
>Hello Bob,
>
>I have read/been-told that cycling the mag switch while at high power
>settings might cause the engine to backfire if one mag is dead and the
>other is turned back on, and that such a backfire might damage components
>of the intake and exhaust systems.. What do you think about this?
That is a risk. Magenetos will do it too but is it a
"backfire"??? When the engine is totally deprived of
ignition it continues to pull stoichiometric mixture through
the plumbing. Then when any source of ignition returns, there's
a volume full of unburned mixture that includes the entire
exhaust system and any cylinder with an exhaust valve open
at the time this volume gets lit off.
I've experienced this on the ground when doing mag checks
where I inadvertently turned off both mags during a run-up
and then got them back on while the engine was still
turning. Folks have done this in their cars too and I've
heard of mufflers being split open from the resulting
explosion. Hmmm . . . guess we need to agree on the word
"backfire" which I use as ignition on the intake side of the
cylinders. Does this make the exhaust side explosion a
"foreward fire"?????
In the common public vernacular, a loud report from a
vehicle is referred to as "backfire" . . . I suppose because
it blows flames out the back of the car . . .
Oh well, I THINK we know what we're talking about!!!!
Bob . . .
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At 01:50 PM 2/22/2007 -0500, you wrote:
>Good Afternoon Matt,
>
>The procedure, as taught, is to be very sure you DO NOT turn on the
>remaining good magneto if the engine does quit. The drill then is to put
>the mixture in full lean, count to ten, turn on the magneto and slowly
>richen the mixture until the engine starts.
>
>I have never had it happen that way and I am sure it will take a lot of
>discipline to wait those few seconds for the engine to clear itself before
>the magneto is placed back in service!
>
>It does help if the operator has experience deliberately running fuel
>tanks dry.
>
>That procedure is another one that is rarely taught these days, but having
>run a tank dry often does instill confidence in the restart procedure.
Hadn't heard that one. Makes a lot of sense. Something
to check my instructor on at the next checkride!
Bob . . .
Message 30
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Thanks Bob
Yup...that is my fear for the long term. I will start an oil analysis
program as the motor will be about 100 hours old at the next change.
Otherwise the engine appears normal. The borescope did not reveal any
signs of pre ignition on the pistons.
Thanks
Frank
Do not archive
________________________________
From: owner-aeroelectric-list-server@matronics.com
[mailto:owner-aeroelectric-list-server@matronics.com] On Behalf Of
BobsV35B@aol.com
Sent: Thursday, February 22, 2007 12:38 PM
Subject: Re: AeroElectric-List: Re: P Mags
Good Afternoon Frank,
Actually, if the timing is advanced, the pressures and temperature can,
and probably will, be much higher than the pressures and temperatures
developed when the fire is lit at the proper point. Any time the peak
pressure point gets closer to TDC than ten or eleven degrees, the crank
shaft has a LOT more resistance and the pressure can be as high as
twelve hundred to fifteen hundred pounds whereas if the ignition event
is properly timed the same engine may never see a pressure above eight
hundred pounds.
It can make a VERY big difference.
Happy Skies,
Old Bob
AKA
Bob Siegfried
Ancient Aviator
Stearman N3977A
Brookeridge Air Park LL22
Downers Grove, IL 60516
630 985-8503
In a message dated 2/22/2007 1:15:55 P.M. Central Standard Time,
frank.hinde@hp.com writes:
Higher than those pressures/stresses that occur when timing
is optimized for maximum realization of available
energy from the fuel?
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Message 31
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Mags
Agreed.. "backfire" is an imprecise term. I used it to mean "any
explosive combustion event which happens at a time or location where it's
not intended to."
I hope we don't need to invent new terminology to cover the specific case
of unintended explosive combustion in the exhaust system.
Fortunately, I think "Old Bob" understood what I was getting at...
Regards,
Matt
> <nuckollsr@cox.net>
>
> At 11:11 AM 2/22/2007 -0700, you wrote:
>
>> <mprather@spro.net>
>>
>>Hello Bob,
>>
>>I have read/been-told that cycling the mag switch while at high power
>>settings might cause the engine to backfire if one mag is dead and the
>>other is turned back on, and that such a backfire might damage components
>>of the intake and exhaust systems.. What do you think about this?
>
> That is a risk. Magenetos will do it too but is it a
> "backfire"??? When the engine is totally deprived of
> ignition it continues to pull stoichiometric mixture through
> the plumbing. Then when any source of ignition returns, there's
> a volume full of unburned mixture that includes the entire
> exhaust system and any cylinder with an exhaust valve open
> at the time this volume gets lit off.
>
> I've experienced this on the ground when doing mag checks
> where I inadvertently turned off both mags during a run-up
> and then got them back on while the engine was still
> turning. Folks have done this in their cars too and I've
> heard of mufflers being split open from the resulting
> explosion. Hmmm . . . guess we need to agree on the word
> "backfire" which I use as ignition on the intake side of the
> cylinders. Does this make the exhaust side explosion a
> "foreward fire"?????
>
> In the common public vernacular, a loud report from a
> vehicle is referred to as "backfire" . . . I suppose because
> it blows flames out the back of the car . . .
>
> Oh well, I THINK we know what we're talking about!!!!
>
> Bob . . .
>
>
Message 32
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| Subject: | JS-AIR Strobe Power pack with Whelen fixtures |
Does anyone have experience using the JS-AIR XPAK 604-HR power pack with the
Whelan A650 position/strobe light fixtures? The JS-AIR is considerably
cheaper and uses less amperage that the Whelen power pack.
Jeff Davidson
Message 33
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| Subject: | Re: JS-AIR Strobe Power pack with Whelen fixtures |
Jeff...I have this set up; Whelen ($180!!!) strobe heads driven by
the Nova XPAC 604 power supply.
I'll be starting it up for the first time in a few days and I'll let
ya know what happens.
Nova (http://www.strobe.com) said it would work way back when I bought it.
Neil
At 06:12 PM 2/22/2007, you wrote:
><jeffrey_davidson@earthlink.net>
>
>Does anyone have experience using the JS-AIR XPAK 604-HR power pack with the
>Whelan A650 position/strobe light fixtures? The JS-AIR is considerably
>cheaper and uses less amperage that the Whelen power pack.
>Jeff Davidson
>
>
>--
>2/22/2007 11:55 AM
Message 34
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In FAA terms a backfire would be fire in the intake which would go "back" t
hrough the carb or throttle body. "afterfiring" or "afterburning" is the te
rm for burning in the exhaust. From a mechanics standpoint it would be nice
to keep them straight because the items to check for damage after a backfi
re are different than an afterfire.
Deems
> Date: Thu, 22 Feb 2007 15:25:52 -0600> To: aeroelectric-list@matronics.co
m> From: nuckollsr@cox.net> Subject: Re: Magneto failure in general, Was: A
eroElectric-List: Re: P Mags> > I've experienced this on the ground when do
ing mag checks> where I inadvertently turned off both mags during a run-up>
and then got them back on while the engine was still> turning. Folks have
done this in their cars too and I've> heard of mufflers being split open fr
om the resulting> explosion. Hmmm . . . guess we need to agree on the word>
"backfire" which I use as ignition on the intake side of the> cylinders. D
oes this make the exhaust side explosion a> "foreward fire"?????> > In the
common public vernacular, a loud report from a> vehicle is referred to as "
backfire" . . . I suppose because> it blows flames out the back of the car
. . .> > Oh well, I THINK we know what we're talking about!!!!> > Bob . . .
=================> > >
_________________________________________________________________
Explore the seven wonders of the world
BRE
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| Subject: | Re: JS-AIR Strobe Power pack with Whelen fixtures |
I don't have them installed on my Velocity yet but do have them to install. I
have seen them in operation on another Velocity. They are at least as bright (I
think brighter than) as a standard Whelen strobe/nav light and give the option
of strobe pattern; ie single flash, double or triple flash, possibly more.
Plus, the lights are enclosed under an aerodynamic clear lens. Way cooler looking
than that clunky Whelen clump.
Bob
-----Original Message-----
From: jeffrey_davidson@earthlink.net
To: aeroelectric-list@matronics.com
Sent: Thu, 22 Feb 2007 5:12 PM
Subject: AeroElectric-List: JS-AIR Strobe Power pack with Whelen fixtures
Does anyone have experience using the JS-AIR XPAK 604-HR power pack with the
Whelan A650 position/strobe light fixtures? The JS-AIR is considerably
cheaper and uses less amperage that the Whelen power pack.
Jeff Davidson
________________________________________________________________________
Message 36
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Mags
That's good info. Thanks for passing it along.. I would have guessed
that afterburning refers to a desirable method of increasing thrust on
turbojets, but that's what I get for guessing I suppose. Looking around
on the google, afterburning appears to be a feature whereas afterfiring
appears to be a fault. I probably haven't looked enough yet...
Regards,
Matt-
> In FAA terms a backfire would be fire in the intake which would go "back"
> through the carb or throttle body. "afterfiring" or "afterburning" is the
> term for burning in the exhaust. From a mechanics standpoint it would be
> nice to keep them straight because the items to check for damage after a
> backfire are different than an afterfire.
>
> Deems
>
>
>> Date: Thu, 22 Feb 2007 15:25:52 -0600> To:
>> aeroelectric-list@matronics.com> From: nuckollsr@cox.net> Subject: Re:
>> Magneto failure in general, Was: AeroElectric-List: Re: P Mags> > I've
>> experienced this on the ground when doing mag checks> where I
>> inadvertently turned off both mags during a run-up> and then got them
>> back on while the engine was still> turning. Folks have done this in
>> their cars too and I've> heard of mufflers being split open from the
>> resulting> explosion. Hmmm . . . guess we need to agree on the word>
>> "backfire" which I use as ignition on the intake side of the> cylinders.
>> Does this make the exhaust side explosion a> "foreward fire"?????> > In
>> the common public vernacular, a loud report from a> vehicle is referred
>> to as "backfire" . . . I suppose because> it blows flames out the back
>> of the car . . .> > Oh well, I THINK we know what we're talking
>> about!!!!> > Bob . . .=================> > >
> _________________________________________________________________
> Explore the seven wonders of the world
> BRE
Message 37
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Mags
Check chapter 10 of AC65-12A for descriptions of the terms and causes. Yes
an Afterburner is for dumping fuel into the exhaust of jet engines for incr
eased thrust. The term afterburn in reference to piston engines probably wa
s in use before jet engines.
Deems
> Date: Thu, 22 Feb 2007 17:38:19 -0700> Subject: RE: Magneto failure in ge
neral, Was: AeroElectric-List: Re: P Mags> From: mprather@spro.net> To: aer
att Prather" <mprather@spro.net>> > That's good info. Thanks for passing it
along.. I would have guessed> that afterburning refers to a desirable meth
od of increasing thrust on> turbojets, but that's what I get for guessing I
suppose. Looking around> on the google, afterburning appears to be a featu
re whereas afterfiring> appears to be a fault. I probably haven't looked en
ough yet...> > > Regards,> > Matt->
_________________________________________________________________
Discover the new Windows Vista
E
Message 38
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Mags
I'm installing the GS-Air LED position lights and strobes powered by Aero
Flash power supplies mounted at the wing tip. I've powered up the position
lights and strobes and I'm very happy with the light output of each and the
low current draw of the LED's. I went with the single flash PS to keep
current draw as low as possible for the strobes. Each wing tip strobe uses
1.5 amps and the LED's are like 0.5 amps.
Mike C.
-----Original Message-----
From: owner-aeroelectric-list-server@matronics.com
[mailto:owner-aeroelectric-list-server@matronics.com] On Behalf Of Matt
Prather
Sent: Thursday, February 22, 2007 4:38 PM
Subject: RE: Magneto failure in general, Was: AeroElectric-List: Re: P Mags
That's good info. Thanks for passing it along.. I would have guessed
that afterburning refers to a desirable method of increasing thrust on
turbojets, but that's what I get for guessing I suppose. Looking around
on the google, afterburning appears to be a feature whereas afterfiring
appears to be a fault. I probably haven't looked enough yet...
Regards,
Matt-
> In FAA terms a backfire would be fire in the intake which would go "back"
> through the carb or throttle body. "afterfiring" or "afterburning" is the
> term for burning in the exhaust. From a mechanics standpoint it would be
> nice to keep them straight because the items to check for damage after a
> backfire are different than an afterfire.
>
> Deems
>
>
>> Date: Thu, 22 Feb 2007 15:25:52 -0600> To:
>> aeroelectric-list@matronics.com> From: nuckollsr@cox.net> Subject: Re:
>> Magneto failure in general, Was: AeroElectric-List: Re: P Mags> > I've
>> experienced this on the ground when doing mag checks> where I
>> inadvertently turned off both mags during a run-up> and then got them
>> back on while the engine was still> turning. Folks have done this in
>> their cars too and I've> heard of mufflers being split open from the
>> resulting> explosion. Hmmm . . . guess we need to agree on the word>
>> "backfire" which I use as ignition on the intake side of the> cylinders.
>> Does this make the exhaust side explosion a> "foreward fire"?????> > In
>> the common public vernacular, a loud report from a> vehicle is referred
>> to as "backfire" . . . I suppose because> it blows flames out the back
>> of the car . . .> > Oh well, I THINK we know what we're talking
>> about!!!!> > Bob . . .=================> > >
> _________________________________________________________________
> Explore the seven wonders of the world
> BRE
Message 39
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| Subject: | P-mags and the RV-7 Off Field Landing |
Darwin, just curious, if he had powered it down but not grounded it, would
the timing from the self power generator be the same or different? Since
there are really three modes, 1) powered 2) unpowered and 3) grounded and
really off,....... would the timing revert to some fixed mechanical advance
in the power off but not grounded mode?
I have one P-Mag and a Slick but not yet flying so I am curious?
Thanks Bill S
_____
From: owner-aeroelectric-list-server@matronics.com
[mailto:owner-aeroelectric-list-server@matronics.com] On Behalf Of Darwin N.
Barrie
Sent: Thursday, February 22, 2007 9:25 AM
Subject: Re: AeroElectric-List: P-mags and the RV-7 Off Field Landing
The gentleman this happened to is a good friend. I received the call that he
has went down and all was safe.
I also have dual Pmags on my plane and have had no problems at all in 185
hours. After he was home safe, I asked him if he had switched between Mags
to see if he could isolate the problem. He did not and said he didn't think
of it.
I agree that the chance of both failing is very slim. Switching each mag off
individually should be part of your check list if a problem arrises. I
personally don't power them off on ground run but only do the L/R/Both
checks.
As Bob said don't paint Emagair with such a wide brush. These guys are
responsive to our needs and have never denied or made any effort to hide an
issue. I continue to have 100% confidence in this system. As with any aspect
of flying, it is critical to know what to do when something goes wrong.
Darwin N. Barrie
Chandler AZ
RV7 N717EE
Message 40
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| Subject: | Connecting to heated pitot tube |
Recently picked up a used heated pitot tube for the plane. Was
wondering if anyone has a good suggestion for how to connect the power
wires to it? There are two steel pins with a diameter of ~.072". Of
course, these can get pretty hot in operation. I think new ones come
with some kind of bakelite connector.
Thanks,
Andy Elliott, Mesa, AZ
N601GE (reserved)
601XL/TD/QB, Corvair, building...
Message 41
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Hi Harley,
I'll give it a try tomorrow. I'm adding a 6 position fuse holder
as I ran out of fuses to do things... Checking out the panel for things
to work so I can close it up soon.
Jim Nelson
RV9-A
Message 42
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| Subject: | RE: Battery Charging - CTEK XS3600 |
Hi Bob,
Something that has been provided as an option over here in NZ is this brand,
sounds like it is at the 'upper' end of the segment, or at least that is
where it is being pitched :-)
http://www.ctek.com/EN/home.asp - "Multi XS3600, max 3.6 amp, ideally
matched to 1.2 to 120 Ah batteries"
Have you seen these in the USA at all, another one for the testing pile
perhaps.
Regards,
Carl
--
ZK-VII - RV 7A QB - finishing? - New Zealand
http://www.rvproject.gen.nz/
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