Cylinder head/barrel separation at 14,500ft.

[DanM20C]

1 hour ago, KLRDMD said:

Don't like the way an engine is running in cruise ? Leisurely shut it down, feather it and continue stress free to the nearest suitable airport on the other engine. Oh, you don't have another engine ? 

There sure seems to have been a lot of engine failures around here in the last year or so.

Ken, your glowing posts about your 231 over the years is a major reason I determined one would fit my mission. Where was all the twin talk back then?  That could have saved me a lot of trouble.

I actually was planing on getting a Barron after my accident.  I don't have a multi rating so I called a school that I new had a Barron.  At the time it was down for a new engine and they didn't expect to finish it for 1-1/2 months.  That time allowed me to think hard about the next airplane.  The Mooney just feels right to me.  And as it turns out, getting insured after a total loss isn't easy.  I honestly don't think I could have got insurance on a twin.

Cheers,

Dan

[carusoam]

Nice work, again, Dan!

I have been told... ‘God only gives us challenges we can handle...’

You have handled the post-accident survival, and the pre-accident survival really extremely well.

That is amazing!

Good luck with the next steps.

Share some more pics and JPI data when you can.

What is making the oil under the tire look like 1/2” of Brown goo?  Or is that an effect of the camera lens?

 

Thanks for sharing, again, 

-a-

[aviatoreb]

9 hours ago, DanM20C said:

I thought of you twice that day. The first time was after the engine started shaking and I thought "Man I wish this was a turbo failure, that would be a lot less expensive."  In my defense I forgot the part about the smoke and burning smell.

The second time I thought of you was while I was standing at my grill with a beer in one hand and the tongs in the other.  Your picture of your sushi popped into my head.  It made me smile.

 

Hi Dan,

Well it makes me happy you thought of my thread over a "I made it" beer.  That sushi photo had glass of saki in it too, remember.  A day like that calls for the good stuff.  You earned it buddy!  Hopefully the repair is not horribly expensive.  Remember.  Less expensive than medical bills.  You did great!  You and I both.  Tonight I will have a beer and think of you back...

[Piloto]

Cylinder separation is mostly due to metal fatigue. This is why I don't trust overhauled cylinders. I always replace with new ones.

José

[jackn]

Congratulations on a great job! You obviously are a cool head.

The TSIO360 cylinders are tough, I was told they are beefier than the big bores. I remember seeing a video from TCM showing a big guy manually screwing the head onto the barrel, yikes. I don't think they do that anymore.

As an aside, unless i'm in mountainous region or have to get up fast for some reason, I'll reduce power from 39" to 32" after about 700 agl. Just sounds better and I lose about 200 ft/min.

[larryb]

I had the same thing happen in my Lycoming IO360. Fortunately it was on the takeoff roll. Never left the ground. I also never figured out why. I could not reliably determine the history of the cylinder and how many total hours it may have had. I replaced it with new. I will never install a used overhauled cylinder.

The one useful thing I did learn was it was probably cracked for a while and leaking exhaust. So now I carefully check the cylinder fins for exhaust residue any time the cowl is off.

[kortopates]

17 hours ago, DanM20C said:

I don't really now the history of the Cylinder.  The OH shop log book entry  just said 6 OHC installed.  I'm not sure if they are first run with the engine or not.  I can't seem to locate a work order with more info. The engine has 2980TT,  720 SMOH.  It's unlikely that the original cylinders would go 2260hrs without overhaul.  If they are original to the engine they would have most likely been OH twice and that would be the problem.  I need to look for work order #'s stamped on the bases of the cylinders. I might be able to tell if these are 2nd or 3rd run.   

Indeed I would be concerned as well. Head separation is do to a combination of metal fatigue and the temperatures they've been operated at. Unlike ferrous metals (steel), non-ferrous metals like our aluminium cyl have no fatigue limit and will always fail eventually if subjected to enough stress cycles. Allowing CHTs to go over 380F repeatedly weakens the aluminium while under stress and speeds up the process to failure. For a much more information on this see Mike's new book "Mike Busch on Engines" and see chapter 10. 

[carusoam]

https://smile.amazon.com/s/ref=nb_sb_ss_i_5_11?url=search-alias%3Daps&field-keywords=mike+busch+books&sprefix=Mike+Busch+%2Caps%2C239&crid=1AIKECALLQ7BZ

-a-

[KLRDMD]

12 hours ago, DanM20C said:

Ken, your glowing posts about your 231 over the years is a major reason I determined one would fit my mission. Where was all the twin talk back then?  That could have saved me a lot of trouble. I actually was planing on getting a Barron after my accident.  I don't have a multi rating so I called a school that I new had a Barron.  At the time it was down for a new engine and they didn't expect to finish it for 1-1/2 months.  That time allowed me to think hard about the next airplane.  The Mooney just feels right to me.  And as it turns out, getting insured after a total loss isn't easy.  I honestly don't think I could have got insurance on a twin.

I loved my 231 and I may have one again at some point. For what it is, it is best of class, in my opinion. But there are risks in flying a single engine airplane. It seems at some points in my life I'm willing to take those risks and other times I'm not willing to. 

[DanM20C]

5 hours ago, aviatoreb said:

Tonight I will have a beer and think of you back...

It’s margaritas here tonight. I will raise a glass to you!

Cheers,

Dan

[DanM20C]

14 hours ago, carusoam said:

What is making the oil under the tire look like 1/2” of Brown goo?  Or is that an effect of the camera lens?

 

I think it is a optical illusion. It was just a puddle of oil.  Nearing oil change time so it is at it’s dirtiest.  But not as nearly as dirty as how the photo depicts.

Cheers 

Dan

[DanM20C]

3 hours ago, kortopates said:

For a much more information on this see Mike's new book "Mike Busch on Engines" and see chapter 10. 

I just ordered the book thanks to Anthony’s Link!

i have been a long time reader of Mr. Bush.  Loved his first book. 

Cheers,

Dan

[bill98]

Glad you landed safely. One where you can walk away is a good thing. 

[DanM20C]

Last week I was able to make it back to the plane to get a closer look and download the JPI data.  The cylinder failed in the classic spot, cracking at the first thread between the barrel and head.  Thankfully, the barrel was completely intact.  Keeping the rings captivated and bad bits of metal or derbies out of the case. 

The #2 Cylinder had a fair amount of cooling fin damage.  Several fins are bent and one has a visible crack around the base of the fin.  I'll be replacing #2 and #4 with two overhauled 1st run cylinders that a friend of mine had on hand.  It will still be a few weeks until the shop has time to get me in.  The poor thing will have spent a month outside.

Some of the damage to #2

e.

I examined the JPI data closely to see what kind of warning signs were there.  The previous dozen or so flights were are very different profiles from normal cruise so it was difficult to see any sort of trend.  But for he most parts the CHT and EGT were very stable and trended the same as the other cylinders.  On the flight where this occurred the CHT for this cylinder started going up 1 degree/min about 20mins before the event, while the egt remained constant.  The last minute prior to the failure the CHT shot up another 20 degrees.  It failed at a CHT of 396.  I didn't notice it go up that high, I wish the JPI900 could set to warn at lower temps than factory. 

It looks to me like the crack started on the lower left of the following photo.  The thermowell for the CHT probe is on the other side of the small cooling fin in the bottom center.  This would explain the slow 1degree/min climb in CHT as there would have been blow-by there. 

Hopefully in a few weeks we will be in the shop and get put back together.

Cheers,

Dan

[ArtVandelay]

The last minute prior to the failure the CHT shot up another 20 degrees.  It failed at a CHT of 396.  I didn't notice it go up that high, I wish the JPI900 could set to warn at lower temps than factory. 

You can, they are called pre-alarms.

How many hours on the cylinders? New or overhauled?

[DanM20C]

28 minutes ago, teejayevans said:

You can, they are called pre-alarms.

How many hours on the cylinders? New or overhauled?

Thanks.  Apparently I haven't read though the manual thoroughly enough.  I just printed the instructions for the pre-alarms and will be setting them up.  

The current cylinders are really unknown.  The engine is around 750 SMOH.  The logs from the engine shop just state that OHC cylinders were installed.  I have no knowledge of the cylinders before that. 

The 1st run replacement cylinders I had overhauled I know the history of and feel confident in.  I would like to to a complete new top end, hoping these 2 OH cylinders can get me a few hundred hours before I pull that trigger.

Dan

[1964-M20E]

2 hours ago, DanM20C said:

  The poor thing will have spent a month outside.

 

Yes she will have to sit outside for a month but she was bad that's her punishment.   A little time out never hurt anyone.

[aviatoreb]

Thank you for posting the pictures, and discussion of your data for our education Dan.

If you can post pictures of your data from the failure flight, and perhaps from a flight before that, I would be ,most grateful.

E

[bonal]

Man that's a pretty thick barrel amazing there is enough pressure to cause a separation like that. What's even more amazing is I figured out how to copy just one photo and paste it onto a reply.

[steingar]

2 pilots on Mooneyspace with big time engine problems and emergency landings on two different Mooney’s each. I gotta stop hanging around here, too much bad luck. It could be catching.

[DanM20C]

1 hour ago, aviatoreb said:

If you can post pictures of your data from the failure flight, and perhaps from a flight before that, I would be ,most grateful.

 

I’ll see what I can do when im back in my office. Unfortunately the previous flights we’re short duration local flights and formation flights. It’s difficult to gather much from that data.

1 hour ago, bonal said:

Man that's a pretty thick barrel amazing there is enough pressure to cause a separation like that.

It is beefy but it’s also aluminum. That is the exact area that see the stress from every combustion cycle. Literally millions of cycles over the life of the cylinder. Aluminum fatigues and will fail eventually. High temperatures can speed the process along. Many early 231 pilots were miss informed, had only one factory  CHT probe, and ran the engines hot. I’m assuming these cylinders were abused in a previous life. I hope the other 4 hold together 

cheers,

Dan

[Guest tommy123]

How would this piston twin owner like it if a turbine driver made the same type of comments about how much safer they are than piston powered aircraft after he had a inflight emergency? There is no arguing that, the failure rate of turbines are no where near that of reciprocating engines. This was definitely a gloat of the “I’ve got a more expensive airplane than you” kind.

Edited August 31, 2018 by tommy123

[kmyfm20s]

The fact that our Mooney’s cowls don’t let us open them easily for engine inspection is something that definitely bothers me. I like the Beech planes in that aspect, easy preflight engine inspection. I look the best I can at oil changes between the cooling fins for any signs of cracking or gas exscaping, of course you cant see all the way around them but something better than nothing. The few cylinders I looked at that suffered head separations looked like they would have shown early signs before the separation happened. I not sure though if you would have had to be unreasonably observant to have caught it in advance. Below are pictures from a 421 that happened at takeoff. The picture angle doesn’t show it well but in person you could easily see where there was old cracked areas leaking and the majority on fresh fractured aluminum.

 

[Raptor05121]

On 8/12/2018 at 12:28 AM, DanM20C said:

  And as it turns out, getting insured after a total loss isn't easy.  I honestly don't think I could have got insurance on a twin.

Cheers,

Dan

 

Dan, is there any sort of "write-up" you could give us on how aviation insurance works after an incident? This is one part of flying I have no knowledge of and it seems to be a limited pool of people to explain.

[Guest]

If this type of failure worries you, ask your maintainer to spray the cylinder heads with soap and water while doing cylinder compression checks.  We’ve found cracked heads this way before.  It only takes a few extra minutes during annual inspection.

Luckily this problem seems to effect TCM engines more than Lycoming engines.

Clarence