Engine failure @ FL190 yesterday

[carusoam]

Sounds like building a ship in a bottle..?

How well Is your JPI working?

Good to have lots of data on the first few flights.

Not that you will need it, but good luck anyways!

Best regards,

-a-

 

[Tony Armour]

Good news. Sorry about your Dad. I wish I had seen this back when you had troubles so that I could have offered some transport. 

My Dad passed out of town (Illinois)  back in July, on a respirator after an accident. Thank goodness for the Mooney, my step mother and I were there that evening to see him and start making our family decisions.

[Yooper Rocketman]

Well, we were at the airport before dawn and I took off just after daybreak.  I did a pretty aggressive climb and was able to stay within 10 miles of the airport up to 10K to get a good 15 minute test flight in.  After landing, we detected no oil leaks, oil level exactly where it was at after last night's run up, and flight test parameters were very normal.  I installed my oil cooler "winter block off", a piece of rubber mud flap cut to fit exactly over 1/2 of my oil cooler in a nice recess (have used it every winter since 2001) to keep oil temps up where they need to be.  I had gotten 190 degrees in the aggressive climb, but started dropping down quickly once level.  Other than that, we felt safe flying it home (well, I did anyway).

http://flightaware.com/live/flight/N1017L  (ignore the filed speed, some anomaly filing with my Iphone.  My file speed at FL180 is 200 knots)

Flew home at FL180 over the lake, and everything seemed great until I started over the lake.  I just thought I detected a slight roughness until I was almost completely over it, and then once I started concentrating on the ILS into my home drome, never noticed anything unusual again during the flight.  Pretty sure it was the "over water jitters" with a recently worked on engine.  I think the last time I watched my gauges that closely during a flight was during break in of my Lycoming Factory Reman IO301A1A in the "F" model back in the 90's.  Anyway, when I landed, while everything was still hot, I pulled the oil filter and cut it open; totally clean.  The oil was exactly on the same spot on the stick (10.5 qts) as when we finished the ground run yesterday, and looked clean as it did when I poured it in the engine.  I also did a compression test and all cylinders were within a couple pounds of my February 2015 annual readings.  I might borescope as long as the plugs are out, but thinking I probably will be good for a while on this engine yet.

Reflecting back on my last annual, I am wondering if I might have detected some play in the turbo back in February had I been diligent enough to check it.  When the air filter is removed on the Rocket, the intake impeller is within view though the back of the housing.  There is a 1/4" mesh at the back of the filter housing which would prevent any decent sized tool to grip the impeller, but I checked with a small magnet on the end of the shaft during reassembly and I think if that could be squeezed through one of the mesh openings.  It appears to grip the impeller shaft sufficiently to check for play in the shaft.  It's something I will do going forward, and just thought this tip might be of value for others with turbos.  This scenario is not one I would like to repeat, nor wish to hear from another turbo owner.  Having it happen in the flight levels near airports is a lot easier to deal with than over mountains or during night operations.

I'll put this thread (and issue) to bed.  The last couple of posts were purely intended as informational.  I fully intend to lurk again for a while and let you guys tell me about the exciting stuff.  

 

[carusoam]

Nicely done, Tom.

Thanks for sharing the data.

Best regards,

-a-

[Mcstealth]

 

 

Reflecting back on my last annual, I am wondering if I might have detected some play in the turbo back in February had I been diligent enough to check it.  When the air filter is removed on the Rocket, the intake impeller is within view though the back of the housing.  There is a 1/4" mesh at the back of the filter housing which would prevent any decent sized tool to grip the impeller, but I checked with a small magnet on the end of the shaft during reassembly and I think if that could be squeezed through one of the mesh openings.  It appears to grip the impeller shaft sufficiently to check for play in the shaft.  It's something I will do going forward, and just thought this tip might be of value for others with turbos.  This scenario is not one I would like to repeat, nor wish to hear from another turbo owner.  Having it happen in the flight levels near airports is a lot easier to deal with than over mountains or during night operations.

I'll put this thread (and issue) to bed.  The last couple of posts were purely intended as informational.  I fully intend to lurk again for a while and let you guys tell me about the exciting stuff.  

 

Did you get a "feel" for the play on the new turbo? I make the assumption you have enough tactile feel with the magnet to know if you have excess play in the turbo. What is too much play? Is there a spec for "play" in the impeller? Is it more of a common sense kind of thing?

[Piloto]

Thanks for sharing your experience. Glad to know things work out OK. How many hours the failed turbo had?

José

[Yooper Rocketman]

There was NO play in the new turbo impeller shaft.  My small magnet gripped it decent enough if there was play I believe I could detect it from distance (through the air filter housing mesh). I know on heavy truck diesel engines a slight amount of play is acceptable,  I cannot say I know what it is on aircraft engine turbos.  Maybe Doc can comment, but otherwise I had planned on doing some research if I found any in the future.  Having wrenched basically my entire life, I guess I expect I should be prudent enough to eliminate as many maintenance issues as possible before they surface as a serious issue.  I will certainly be reviewing the annual inspection check list to see if we should have been scrutinizing the turbo closer.  I've had annuals done by several shops in the past (when too busy to do them ourselves), but mostly complete them myself with Steve, my hangar partner and A&P.  My squawk lists are always 3-4 times longer than I ever get from the shops, but then they are not getting nick picky either with stuff that would more likely P... off customers.  

The last turbo was installed about 800-1000 hours ago, which means the first one only lasted about the same amount of time too.  I bought the Rocket with 300 SMOH, but only 10 since a complete tear down and everything but a few items short of another OH due to a prop strike during a botched landing.  The last failure was detected during exhaust piping work (had some cracks and sent out the complete exhaust for overhaul) when I spotted some decay/erosion of the exhaust impeller.  I sent it out to Main Turbo in California for overhaul.  I suspected the first failure was the prior owner (or my new ownership) operations, as that type of failure is most likely from over temps in the exhaust system.  I am pretty certain my operations on the one that just failed were completely within parameters so we sent the turbo out to a different overhaul shop (think it was ATS). Recent articles I have read about aircraft turbos, they SHOULD last the life of the engine, so I am not real happy with my turbo life on this bird.  In the end, I got a new turbo because there was nothing reusable on my old core.  They actually pulled the "Garrett" tag off and installed an "ATS" tag on the side of the turbo, leaving the original Garrett tag in my accessories bag.  With my project plane within 6-9 months of completion, I suspect that any future turbo failure will be with the next owner.

[aviatoreb]

 

There was NO play in the new turbo impeller shaft.  My small magnet gripped it decent enough if there was play I believe I could detect it from distance (through the air filter housing mesh). I know on heavy truck diesel engines a slight amount of play is acceptable,  I cannot say I know what it is on aircraft engine turbos.  Maybe Doc can comment, but otherwise I had planned on doing some research if I found any in the future.  Having wrenched basically my entire life, I guess I expect I should be prudent enough to eliminate as many maintenance issues as possible before they surface as a serious issue.  I will certainly be reviewing the annual inspection check list to see if we should have been scrutinizing the turbo closer.  I've had annuals done by several shops in the past (when too busy to do them ourselves), but mostly complete them myself with Steve, my hangar partner and A&P.  My squawk lists are always 3-4 times longer than I ever get from the shops, but then they are not getting nick picky either with stuff that would more likely P... off customers.  

The last turbo was installed about 800-1000 hours ago, which means the first one only lasted about the same amount of time too.  I bought the Rocket with 300 SMOH, but only 10 since a complete tear down and everything but a few items short of another OH due to a prop strike during a botched landing.  The last failure was detected during exhaust piping work (had some cracks and sent out the complete exhaust for overhaul) when I spotted some decay/erosion of the exhaust impeller.  I sent it out to Main Turbo in California for overhaul.  I suspected the first failure was the prior owner (or my new ownership) operations, as that type of failure is most likely from over temps in the exhaust system.  I am pretty certain my operations on the one that just failed were completely within parameters so we sent the turbo out to a different overhaul shop (think it was ATS). Recent articles I have read about aircraft turbos, they SHOULD last the life of the engine, so I am not real happy with my turbo life on this bird.  In the end, I got a new turbo because there was nothing reusable on my old core.  They actually pulled the "Garrett" tag off and installed an "ATS" tag on the side of the turbo, leaving the original Garrett tag in my accessories bag.  With my project plane within 6-9 months of completion, I suspect that any future turbo failure will be with the next owner.

Hi Yooper, I am not fully understanding the tool/test you are suggesting to test for excessive turbo play, and I would like to please.

 

[merrja]

Quoted: I just thought I detected a slight roughness until I was almost completely over it, and then once I started concentrating on the ILS into my home drome, never noticed anything unusual again during the flight.  Pretty sure it was the "over water jitters" with a recently worked on engine.

 

 

I hear it's called "Automatic Rough", the noise your engine starts to make as soon as you begin crossing a large body of water.  Oddly enough enough whatever mechanical issue causes the rough running engine usually cures itself as soon as you are within gliding distance to land.  I've experienced it over lake Michigan as well as the Caribbean! 

[Yooper Rocketman]

"Hi Yooper, I am not fully understanding the tool/test you are suggesting to test for excessive turbo play, and I would like to please."

Just basically a small (pocket size, like a pen) extendable magnet tool.  The mesh at the back of the air filter assy is to support the foam filter.  You can view the intake impeller through the mesh, but it is about 8" back from the mesh.  Short of removing the air filter assy, which is a real pain (8 small screws, safety wired, and half of them almost impossible to access) this was the only option we could think of to inspect for play.  I placed my small magnet on the end of the impeller shaft before installing the turbo and felt it gripped it sufficiently enough to detect any future play in the shaft and bearings.

I might check to see if I can get my arm up the exhaust pipe to grab the exhaust impeller.  That might be a second option.

[aviatoreb]

 

"Hi Yooper, I am not fully understanding the tool/test you are suggesting to test for excessive turbo play, and I would like to please."

Just basically a small (pocket size, like a pen) extendable magnet tool.  The mesh at the back of the air filter assy is to support the foam filter.  You can view the intake impeller through the mesh, but it is about 8" back from the mesh.  Short of removing the air filter assy, which is a real pain (8 small screws, safety wired, and half of them almost impossible to access) this was the only option we could think of to inspect for play.  I placed my small magnet on the end of the impeller shaft before installing the turbo and felt it gripped it sufficiently enough to detect any future play in the shaft and bearings.

I might check to see if I can get my arm up the exhaust pipe to grab the exhaust impeller.  That might be a second option.

Hi - thanks for the detail.  I understand now the tool you are suggesting, but I am still not exactly understanding the place where you are getting this access.  I will need a mechanic to help describe to me?  If you ever get a chance to take a picture of yourself accessing this location with your tool, next time you do it, it would be most appreciated.

[carusoam]

The impeller is made of a version of SS. How well the magnet grips it could be interesting.

sensing the play and smoothness of spinning would be interesting if that is possible.

could be helpful with a PPI as well.

Best regards,

-a-

[Yooper Rocketman]

"The impeller is made of a version of SS. How well the magnet grips it could be interesting."

The shaft is NOT Stainless.  I have already gripped it with the magnet and determined it grips securely enough to check for play in the shaft/bearings.

" I understand now the tool you are suggesting, but I am still not exactly understanding the place where you are getting this access."

If you remove your air filter you will see a mesh at the rear of the filter housing designed to keep the foam filter from being sucked into the turbo inlet.  I will expand one of the openings just a bit to get the magnet through.  The turbo shaft and impeller are about 8" behind the mesh.  I will be working on the Rocket soon, wrapping up a couple minor issues we left to finish once I got home.  I will take a picture for you.

Tom

[Yooper Rocketman]

Erik,

As promised, here is a view of the turbo through the air filter housing.  I inspected everything that was touched during the turbo replacement after getting home.  Removing the housing would only entail removing 4 more bolts, but from experience, those 4 bolts are a real pain.  I will try to get a small magnet through the openings in the mesh to inspect for play in the turbo shaft during my future annuals.

Tom