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Hiccup


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9 minutes ago, aviatoreb said:

https://apps.savvyaviation.com/flights/6067546/867fa246-22d1-41fc-8e82-21f169b5f750

Can you all view this  my file?

The hiccup from memory would be somewhere between min 9 which is when take off roll starts which you see when FF hits 34gph and then about 15min which is part way through cruise climb.  I don't see anything in the data suggesting a hiccup.

I snipe text and also screen shots all the time - but something seems to have changed on Mooneyspace where I don't know right now how to post pictures I have as files where I used to until recently.

Yes.  I can see it as well.

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For what it is worth, I had the same thing happen on my IO-550. Check your mags right after the stumble. I had one cylinder not firing on the right mag. You will clinch a bit of seat upholstery but if you have a bad mag, it will most likely show up in a big way. Yeah, I thought it was water at first but nope it was a bad mag with only 317 hours on it. Sometimes they just throw craps. A run up mag check will often not show a bad mag until the engine is at full power under load.

 

 

 

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1 hour ago, GeeBee said:

For what it is worth, I had the same thing happen on my IO-550. Check your mags right after the stumble. I had one cylinder not firing on the right mag. You will clinch a bit of seat upholstery but if you have a bad mag, it will most likely show up in a big way. Yeah, I thought it was water at first but nope it was a bad mag with only 317 hours on it. Sometimes they just throw craps. A run up mag check will often not show a bad mag until the engine is at full power under load.

 

 

 

Huh!  A mag.  That never occurred to me.  But would that allow it to run smooth as silk after the hiccup?  

I have one electronic mag and one traditional mag by the way and the electronic one might be so strong a spark that it would otherwise mask a bad traditional mag.  Its less likely that the electronic mag is bad - it only has 400 hrs on it and they are less common to go so quickly with all solid state parts.

So the only way to test this is an in-flight mag check?  Or can I do a full power on the ground mag check - or at least a high power mag check - like 85% like I was in cruise climb.

For what its worth I flew today including two full stops two from stop start ups and two full mag checks and no problem in the mag checks, the climb out or cruise.  As if nothing ever happened. 

I got a new headset I was test driving!  zulu 3 !

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55 minutes ago, Fly Boomer said:

I think the run-up mag check is good to do, but probably only ferrets out gross mag problems.  In-flight at cruise power should be more of a test -- especially at altitude.

Ugh - Ill do that - I hate doing that since I always feel its creepy.

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12 hours ago, aviatoreb said:

Ugh - Ill do that - I hate doing that since I always feel its creepy.

Check out the in-flight mag check described on page 2:

https://resources.savvyaviation.com//wp-content/uploads/articles_eaa/EAA_2010-12_the-mag-check.pdf

12 hours ago, aviatoreb said:

Drag and drop used to work - but it no longer seems to work.  I dunno.

There is also a "choose files" link at the bottom of a post that you are creating.  I have had times when that worked, but drag and drop didn't.  Also, you may have reached your upload limit.  When our server ran out of allocated disk space, the administrator had to delete a bunch of uploads to get the system back on line.  Now, we each have a limit so that doesn't happen again unexpectedly.

If you have reached your limit, donate $25 (or more) and your limit goes up.  I use PayPal.  And you help keep MooneySpace alive.  The link for donations is:

https://www.paypal.com/donate/?cmd=_s-xclick&hosted_button_id=K8XHCJ34JXT7W

If all else fails, contact Craig @Mooniac58.

 

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On 8/3/2022 at 4:05 PM, aviatoreb said:

Huh!  A mag.  That never occurred to me.  But would that allow it to run smooth as silk after the hiccup?  

I have one electronic mag and one traditional mag by the way and the electronic one might be so strong a spark that it would otherwise mask a bad traditional mag.  Its less likely that the electronic mag is bad - it only has 400 hrs on it and they are less common to go so quickly with all solid state parts.

So the only way to test this is an in-flight mag check?  Or can I do a full power on the ground mag check - or at least a high power mag check - like 85% like I was in cruise climb.

For what its worth I flew today including two full stops two from stop start ups and two full mag checks and no problem in the mag checks, the climb out or cruise.  As if nothing ever happened. 

I got a new headset I was test driving!  zulu 3 !

If you have a SureFly that’s over about a year old, it will be susceptible to rebooting if it gets a voltage spike over 32 volts (so it’s more likely to occur if you have a 28 volt system). The reboot will take the mag off line for about 300 ms. 

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16 minutes ago, PT20J said:

If you have a SureFly that’s over about a year old, it will be susceptible to rebooting if it gets a voltage spike over 32 volts (so it’s more likely to occur if you have a 28 volt system). The reboot will take the mag off line for about 300 ms. 

Huh!  No kidding.

Mine is about 2 years old.

But I have a 14 volt system. Also about 3 months ago I replaced my voltage regulator with a solid state voltage regulator and also a new alternator, while chasing some radio noise.  

Still!  Interesting lead.  Thanks!  How would I confirm if that was it?

Inspecting my savvy file shows voltage at 13.8 absolutely flat!  But if there is a spike it is shorter than the sampling rate I have the edm830.

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1 hour ago, aviatoreb said:

Huh!  No kidding.

Mine is about 2 years old.

But I have a 14 volt system. Also about 3 months ago I replaced my voltage regulator with a solid state voltage regulator and also a new alternator, while chasing some radio noise.  

Still!  Interesting lead.  Thanks!  How would I confirm if that was it?

Inspecting my savvy file shows voltage at 13.8 absolutely flat!  But if there is a spike it is shorter than the sampling rate I have the edm830.

According to Jason at SureFly, the spikes are usually very short and the only way he found them was with an oscilloscope. I don't believe he's ever seen them cause a problem on 14 V systems. But there is a chance that it was a one time transient of some sort. Were you operating any other equipment at the time? Jason told me that he tracked some incidents down to electric motors operating. 

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With only a blip in power…

response rate of most sensors won’t ever notice the blip…

data collection rate of one second will most likely miss the microsecond blip…

But the ears and vibration sensors noticed a change…

Did the fast blip cause an extended response from something like prop rpm?

the mechanical response of an oil operated valve is kind of slow compared to everything else…

was there any noticeable rpm oscillation?

+1 for the value of inflight mag tests… they are a bit more sensitive than the ground run variety…

have no fear…  you have proven skills for M20K glider flight!  :)

PP guesses only…

Best regards,

-a-

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1 hour ago, carusoam said:

have no fear…  you have proven skills for M20K glider flight!  :)

Thanks - but that experience has only made me respect that concept that it doesn't just happen to other guys and to realize that there was a good dose of both skill and luck involved in the good outcome.  So I am trying to use superior planning rather than superior skill, and not rely on luck.

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1 hour ago, PT20J said:

According to Jason at SureFly, the spikes are usually very short and the only way he found them was with an oscilloscope. I don't believe he's ever seen them cause a problem on 14 V systems. But there is a chance that it was a one time transient of some sort. Were you operating any other equipment at the time? Jason told me that he tracked some incidents down to electric motors operating. 

Skip

Hmmm....I don't think I want to fly around with an oscilloscope!  That makes sense.

Equipment - well all the usual stuff - instruments.  Radio?

Electric motor - the gear swing - happened 1 or 2 minutes before.

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Basically an engine oscilloscope. You had a switch to select the engine, and the cylinder. You could check the low tension side, the high tension side for each and every cylinder and it's two spark plugs along with engine vibrations and cylinder detonation. So on the B-36 with 6, 28 cylinder engines you could look at and monitor 168 different cylinders or 336 different spark plug leads. It was the flight engineer's job to monitor.

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14 minutes ago, GeeBee said:

Basically an engine oscilloscope. You had a switch to select the engine, and the cylinder. You could check the low tension side, the high tension side for each and every cylinder and it's two spark plugs along with engine vibrations and cylinder detonation. So on the B-36 with 6, 28 cylinder engines you could look at and monitor 168 different cylinders or 336 different spark plug leads. It was the flight engineer's job to monitor.

WOW - that's cool.

I'll stick with the LOP mag check and call it a day. If it passes.

I haven't had time the last few days - it will likely be mid week before I can.  Stay tuned!

 

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Hello all.  I did the inflight LOP - it is really freaky doing it knowing that if you do have a bad mag you might be shutting off the engine in flight - so I did it at 6k directly over a nice two runway airport, KMSS not far from here.  

At 55%.  You can see the file here https://apps.savvyaviation.com/flights/6098917/abe74cdd-9dea-4c04-a005-935a7e71fbc2

I did on left mag twice since I know the first time I probably didn't dwell on one mag long enough.

Everything was fine.  it passed just fun.  Engine was a bit rougher with just one mag, as expected - but not terribly rough, just a bit rough.  Tit tends to soar on one mag, but I only let it for a few seconds.

So that's that - the hiccup event of last week is officially a mystery event - likely related to perhaps some kind of fuel contaminant.

It was a gorgeous evening.

 

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15 minutes ago, aviatoreb said:

Hello all.  I did the inflight LOP - it is really freaky doing it knowing that if you do have a bad mag you might be shutting off the engine in flight - so I did it at 6k directly over a nice two runway airport, KMSS not far from here.  

At 55%.  You can see the file here https://apps.savvyaviation.com/flights/6098917/abe74cdd-9dea-4c04-a005-935a7e71fbc2

I did on left mag twice since I know the first time I probably didn't dwell on one mag long enough.

Everything was fine.  it passed just fun.  Engine was a bit rougher with just one mag, as expected - but not terribly rough, just a bit rough.  Tit tends to soar on one mag, but I only let it for a few seconds.

So that's that - the hiccup event of last week is officially a mystery event - likely related to perhaps some kind of fuel contaminant.

It was a gorgeous evening.

 

Do you have a Surefly?  I’ve been wanting to do a lop mag check, but I wonder how it will come out since I’m running a Surefly with advance.  At 6000 feet and very lean of peak, the engine is running almost exclusively off the surefly. When I switch to the Surefly the engine just barely changes. When I shift to the mag, it gets rough and EGT‘s rise a lot. That doesn’t mean the mag is bad, but it was running almost up just off of the Surefly.  Did yours do that?

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15 minutes ago, Ragsf15e said:

Do you have a Surefly?  I’ve been wanting to do a lop mag check, but I wonder how it will come out since I’m running a Surefly with advance.  At 6000 feet and very lean of peak, the engine is running almost exclusively off the surefly. When I switch to the Surefly the engine just barely changes. When I shift to the mag, it gets rough and EGT‘s rise a lot. That doesn’t mean the mag is bad, but it was running almost up just off of the Surefly.  Did yours do that?

I am running surefly.

I didn't notice what you are describing, but I wasn't looking for it.  I presume the ignition is running mostly off the hotter surefly, as you say, but when off, that the classic mag is enough to mostly run the ignition just fine.  The Tit being the biggest tell as it rises a lot.

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18 minutes ago, aviatoreb said:

I am running surefly.

I didn't notice what you are describing, but I wasn't looking for it.  I presume the ignition is running mostly off the hotter surefly, as you say, but when off, that the classic mag is enough to mostly run the ignition just fine.  The Tit being the biggest tell as it rises a lot.

Ahh, I didn’t realize you have a turbo.  Your SF is set to Fixed timing, so it doesn’t have the same issue. Since mine has advanced timing (I’m not turbo) when I’m lean of peak at a higher altitude it’s mostly running off the Surefly firing the cylinder first and the mag firing just after the SF.  Your SF and MAG are still firing at the same time with Fixed timing, so it doesn’t have the same issue.

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6 minutes ago, Ragsf15e said:

Ahh, I didn’t realize you have a turbo.  Your SF is set to Fixed timing, so it doesn’t have the same issue. Since mine has advanced timing (I’m not turbo) when I’m lean of peak at a higher altitude it’s mostly running off the Surefly firing the cylinder first and the mag firing just after the SF.  Your SF and MAG are still firing at the same time with Fixed timing, so it doesn’t have the same issue.

I agree.  Good analysis.

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