Hiccup

[aviatoreb]

I had a creepy hiccup today.

The engine made a single studder today - like so brief as if it was one cycle of the engine - during climb out but not immediately but like as I was passing through maybe 3500 ft.  Before and after it was running as smooth as can be.  Creating good full power.  No indications on the instruments during flight or anything I can see out of spec on the download now after the flight.  So I had never felt such a thing before but I have read about it, and people seem to chalk it up to a fuel contaminant passing through?  Water?  I did sump but that is not a bullet proof guarantee for a droplet.  or it was pretty hot - bubbles?  I don't know.  Since all seemed fine, I continued but I was on hair trigger more than usual just in case watching all the time the nearby alternates and glide rings. 

What can I do to look more into this?  Or is it just one of those things that can and does happen once and a while - although not in 1200 hrs of my time behind this engine.  Or is it a harbinger I can investigate further somehow?

[Eight8Victor]

This is indeed unusual. The only time it seems to happen to me is night flights over water or mountains. :)

Seriously though, I have had a similar experience. Landed at the nearest airport and had the local mechanic check my fuel injector nozzles. He found nothing and suggested it was something that passed through in the fuel. 

[Mooneymite]

I seem to remember multiple posts about this phenomenon on Mooneyspace over the years and I have experienced it myself with my O-360.  Just a very brief "roughness" then everything returns to normal.

When It happened to me, I presumed it was a "bubble" of water that had failed to show up in the fuel sample.  No long term ill effects, no answers, no solutions....just an "anomaly".

However, as the previous poster alluded, expect this as soon as you go feet-wet on your trip to the Bahamas.  "It's all in your head, mon."  

[ArtVandelay]

No engine monitor?

[aviatoreb]

Yah it’s what I was guessing would be the thought.  Fuel contaminant or something passing through.

It was so brief it’s hard to call it engine roughness.  It was a studded so brief as if a single stroke but completely unmistakable.

Ive seen all those similar threads come through over the years / maybe I didn’t pay close enough attention / but first time it happened to me!

[Fly Boomer]

6 minutes ago, aviatoreb said:

Ive seen all those similar threads come through over the years / maybe I didn’t pay close enough attention / but first time it happened to me!

I used to follow the Cessna 195 forum, and read about this phenomenon with the Jacobs radial.

[aviatoreb]

4 minutes ago, Fly Boomer said:

I used to follow the Cessna 195 forum, and read about this phenomenon with the Jacobs radial.

What’s the general thought over there?

Water?

Fod in the fuel or perhaps passing through the fuel injector?

Something bad to worry about?  Nothing?

Whatever it was it was too brief to register on the downloaded engine data.

e

[Fly Boomer]

2 minutes ago, aviatoreb said:

What’s the general thought over there?

Gremlins?  I don't recall ever reading a solution, let alone a believable cause.  I could be convinced it was a little blob of water.  I never felt like our fuel sumps were 100% reliable.

[EricJ]

I'm a little envious of people who have engines where a single little hiccup would be considered so unusual. 

 

[aviatoreb]

8 minutes ago, Fly Boomer said:

Gremlins?  I don't recall ever reading a solution, let alone a believable cause.  I could be convinced it was a little blob of water.  I never felt like our fuel sumps were 100% reliable.

My thought is blob of water too.

gremlin.

oh… and my wife was with me - a tepid flier who only goes if we go somewhere really fun.  We went to Maine.  She flies with me maybe 1 in 2p of the hours I put in. Of course she was with me when gremlin visited. And it was enough she asked me what’s that.  Why can’t gremlin visit on the other 19 hrs?!!

[Fly Boomer]

1 minute ago, aviatoreb said:

Of course she was with me when gremlin visited.

Passengers do seem to be hypervigilant.  After we have flown a few hours, I think we come to grips with the reality that even if the fan stops entirely, we usually have some time to pick a good spot.  Passengers don't want to hear that.

[carusoam]

We have been discussing hot temps and TC’d Mooneys…

…and the little experienced fuel vaporization that can occur.….and what to do when it occurs…

Probable explanation of Mark’s Acclaim engine out disaster that recently got its final report… 

 

Lets get the data from the engine monitor to see if FP or FF had any blips in it…

How hot was the OAT?

Best regards,

-a-

[carusoam]

Inviting @donkaye for his insight…

Best regards,

-a-

 

 

 

[aviatoreb]

13 hours ago, carusoam said:

We have been discussing hot temps and TC’d Mooneys…

…and the little experienced fuel vaporization that can occur.….and what to do when it occurs…

Probable explanation of Mark’s Acclaim engine out disaster that recently got its final report… 

 

Lets get the data from the engine monitor to see if FP or FF had any blips in it…

How hot was the OAT?

Best regards,

-a-

How do I share my savvy file?  I never did that before?

I don't remember the exact minute of the hiccup but I am pretty sure it was during the first 5 min of flight.  I am going to include a screen shot.  I think it was shortly after I dialed back from 100% climb power to 85% cruise climb power which is easy to see in the fuel flow dropped to 27gph.  OAT was 24C on the ground, and interestingly 26C up through about 2000ft before OAT starts dropping.   SO a nice warm summer day but not particularly hot - it was seaside Maine after all.  And hottest cylinder was rising through about 375 at the time, and got to 383 before cooling off with increased climb speed as cooling action - which was after the hiccup.

So whatever happened its nothing I can see in the file but maybe someone else can - if I can get some advice as to how to post it?

...huh - and Mooneyspace's front end has changed recently - I don't know how to attach a picture now. Of the screen shot of the savvy.

Edited August 2, 2022 by aviatoreb

[Fly Boomer]

6 minutes ago, aviatoreb said:

Mooneyspace's front end has changed recently - I don't know how to attach a picture now.

Drag and drop is easiest.

[Ragsf15e]

2 hours ago, aviatoreb said:

How do I share my savvy file?  I never did that before?

I don't remember the exact minute of the hiccup but I am pretty sure it was during the first 5 min of flight.  I am going to include a screen shot.  I think it was shortly after I dialed back from 100% climb power to 85% cruise climb power which is easy to see in the fuel flow dropped to 27gph.  OAT was 24C on the ground, and interestingly 26C up through about 2000ft before OAT starts dropping.   SO a nice warm summer day but not particularly hot - it was seaside Maine after all.  And hottest cylinder was rising through about 375 at the time, and got to 383 before cooling off with increased climb speed as cooling action - which was after the hiccup.

So whatever happened its nothing I can see in the file but maybe someone else can - if I can get some advice as to how to post it?

...huh - and Mooneyspace's front end has changed recently - I don't know how to attach a picture now. Of the screen shot of the savvy.

I look carefully through the fuel pressure, fuel flow and EGTs during that time to see if you can identify exactly where it happens, then look at all the other parameters.  Most of them (CHT, Oil temp, etc) won’t change fast enough to capture a hiccup.  

[aviatoreb]

17 minutes ago, Ragsf15e said:

I look carefully through the fuel pressure, fuel flow and EGTs during that time to see if you can identify exactly where it happens, then look at all the other parameters.  Most of them (CHT, Oil temp, etc) won’t change fast enough to capture a hiccup.  

I wish I could learn how to post my savvy here so others can look.

I have loved very very closely at fuel flow and EGT - I see no sign.  As I said it felt as if it skipped a single beat - but it was clear and unmistakable, but perhaps faster than the sensors could measure.  I don't know.

[Schllc]

12 hours ago, aviatoreb said:

I wish I could learn how to post my savvy here so others can look.

I have loved very very closely at fuel flow and EGT - I see no sign.  As I said it felt as if it skipped a single beat - but it was clear and unmistakable, but perhaps faster than the sensors could measure.  I don't know.

I will qualify the following comment with what I am assuming you experienced is the same that I have. Not violent, not prolonged, and not repeated….

I have always called this the “piston burp”.
I am not sure I’ve owned a plane that hasn’t done this at one point or another to some degree or another. 
My experiences were rare, without obvious rhyme or reason.  Not enough regularity to note to be honest. 
This doesn’t  make them any less disturbing when it happens, but when I discussed with other friends, they had all experienced this at one time or another, and said that’s just an idiosyncrasy of a piston engine. 
Turbines apparently eliminate this completely.

[aviatoreb]

50 minutes ago, Schllc said:

I will qualify the following comment with what I am assuming you experienced is the same that I have. Not violent, not prolonged, and not repeated….

I have always called this the “piston burp”.
I am not sure I’ve owned a plane that hasn’t done this at one point or another to some degree or another. 
My experiences were rare, without obvious rhyme or reason.  Not enough regularity to note to be honest. 
This doesn’t  make them any less disturbing when it happens, but when I discussed with other friends, they had all experienced this at one time or another, and said that’s just an idiosyncrasy of a piston engine. 
Turbines apparently eliminate this completely.

Thanks for that.

I have about 1400 hrs and I have owned two airplanes, a DA40 then this one for about 1100+ hrs. I have read about piston burp - but never experienced it.  It is very disturbing since it throws me into immediate emergency response mode.  I have read elsewhere and here on the topic more seriously in the last two days, and poured over my savvy file (there is absolutely no indicator I can see that it happened since I think it was a single "burp" of a single stroke of the pistons - a pronounced shudder but oh so brief to fast for the sampling rate of the sensors).  That I think this is considered "nothing".  Ugh.

 

[Greg Ellis]

21 hours ago, aviatoreb said:

I wish I could learn how to post my savvy here so others can look.

I have loved very very closely at fuel flow and EGT - I see no sign.  As I said it felt as if it skipped a single beat - but it was clear and unmistakable, but perhaps faster than the sensors could measure.  I don't know.

You should be able to go to the actual graph of the flight on Savvy and cut and paste the URL that is at the top of the page here.  That should give access to everyone to see the flight.

[Marauder]

You should be able to go to the actual graph of the flight on Savvy and cut and paste the URL that is at the top of the page here.  That should give access to everyone to see the flight.

Or if he is using a Windows PC he could use the snipping tool.


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[aviatoreb]

24 minutes ago, Marauder said:

Or if he is using a Windows PC he could use the snipping tool.


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Mac

[Marauder]

Mac

There are snipping tool equivalent out there for a Mac. Some may be free. You wouldn’t want to jeopardize your CH membership.

https://www.apowersoft.com/snipping-tool-for-mac.html


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[aviatoreb]

29 minutes ago, Marauder said:

There are snipping tool equivalent out there for a Mac. Some may be free. You wouldn’t want to jeopardize your CH membership.

https://www.apowersoft.com/snipping-tool-for-mac.html


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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.

[Marauder]

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.

I can open it.



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