Turbo v clamp

[kortopates]

22 minutes ago, carusoam said:

how many hours are we getting before being replaced for other reasons?

Just looking at the pictures of the failed one, they all look very corroded as if they had been in service for multiple decades with other exhaust issues going on.

A key requirement of the Best Practices document is to perform an real inspection on these annually. If actually done, that alone should give these enough attention to cure the problem. 

[AeroEng]

Considering the difficulty I had in finding one of these clamps earlier this year, I can’t imagine how hard it will be now that the entire fleet has to replace them…. 
 

I have ONE as a spare at the moment, but all us Acclaim owners will need TWO if the AD goes through…

[Fly Boomer]

18 hours ago, kortopates said:

yep, the AD will require following the FAA Best practices guide for turbo exhaust components

Where would we find the Best Practices Guide?

[N201MKTurbo]

17 minutes ago, Fly Boomer said:

Where would we find the Best Practices Guide?

https://www.faa.gov/aircraft/air_cert/design_approvals/small_airplanes/cos/aging_aircraft/media/maintaining_exhaust_system_best_practices.pdf

 

[Fly Boomer]

4 minutes ago, N201MKTurbo said:

https://www.faa.gov/aircraft/air_cert/design_approvals/small_airplanes/cos/aging_aircraft/media/maintaining_exhaust_system_best_practices.pdf

 

Thank you!  I'm pretty good at finding things on the Internet, but not sure I would have dug down into the FAA site far enough for this.

[N201MKTurbo]

Wow, I just thumbed through the best practices guide. The failure pictures look horrible. Those clamps should have been replaced years ago. 

It reminds me of the exhaust inspection on the turbo twin Cessna's. I do those periodically. the failure pictures that led to that AD also show horribly neglected exhaust systems.  

[N201MKTurbo]

1 minute ago, Fly Boomer said:

Thank you!  I'm pretty good at finding things on the Internet, but not sure I would have dug down into the FAA site far enough for this.

The AD text gave clues of where to find it.

[Pinecone]

A quick look at the AD is for the spot welded clamps.

The SB mentioned early required the replacement of them for Mooneys.

 

[N201MKTurbo]

15 minutes ago, Pinecone said:

A quick look at the AD is for the spot welded clamps.

The SB mentioned early required the replacement of them for Mooneys.

 

The AD addresses both spot welded and riveted clamps. The inspection interval is the same but the replacement interval is different. Spot welded 500 hours, riveted 2000 hours.

[EricJ]

2 hours ago, N201MKTurbo said:

https://www.faa.gov/aircraft/air_cert/design_approvals/small_airplanes/cos/aging_aircraft/media/maintaining_exhaust_system_best_practices.pdf

 

That doc is triggering the crap out of my engineering technical writing OCD.   There is no authorship attribution, even to an agency or institution, so who knows where it came from.   It says it was driven by a Working Group, but doesn't claim it was sourced from there or what member(s) or committee may have written it.   Many of the figures aren't numbered or captioned, but some are...arg.   The un-numbered and un-captioned figures are often directly referenced by the text, so fingers crossed that nobody ever edits or updates those parts.  There's no revision or revision history indicated, so one might be led to believe this is the first release, but who knows.  This is just me ranting about pet peeves after writing way too many similar docs where such details were important, and they should be in this case, too.   It is at least dated, which is good.

The safety wire example drawings in the (fortunately numbered) Figures 12 and 13 aren't very good, so I went online to look for some other references or examples.   My fave so far is the Navy guidance to just wrap a couple turns around the t-bolt stays.

Since this isn't an AD yet I'll be interested to see what actually happens.   The current suggested recommendations do seem a bit overkill, so maybe enough people will feed back some useful data that if something does come out it'll be a bit more practical.    Given the consequences of failed clamps and that sufficient events have apparently driven this up to the level of a proposed AD, maybe some improved inspection/replacement intervals will be worthwhile for the fleet.

 

[N201MKTurbo]

2 minutes ago, EricJ said:

That doc is triggering the crap out of my engineering technical writing OCD.   There is no authorship attribution, even to an agency or institution, so who knows where it came from.   It says it was driven by a Working Group, but doesn't claim it was sourced from there or what member(s) or committee may have written it.   Many of the figures aren't numbered or captioned, but some are...arg.   The un-numbered and un-captioned figures are often directly referenced by the text, so fingers crossed that nobody ever edits or updates those parts.  There's no revision or revision history indicated, so one might be led to believe this is the first release, but who knows.  This is just me ranting about pet peeves after writing way too many similar docs where such details were important, and they should be in this case, too.   It is at least dated, which is good.

The safety wire example drawings in the (fortunately numbered) Figures 12 and 13 aren't very good, so I went online to look for some other references or examples.   My fave so far is the Navy guidance to just wrap a couple turns around the t-bolt stays.

Since this isn't an AD yet I'll be interested to see what actually happens.   The current suggested recommendations do seem a bit overkill, so maybe enough people will feed back some useful data that if something does come out it'll be a bit more practical.    Given the consequences of failed clamps and that sufficient events have apparently driven this up to the level of a proposed AD, maybe some improved inspection/replacement intervals will be worthwhile for the fleet.

 

Eric,

You should forward this to the FAA comment website for the AD. 

I would think the AD could just say, "If the clamp is rusty and obviously overheated, replace it" All the examples looked overheated or over torqued or both.

[N201MKTurbo]

5 hours ago, AeroEng said:

Considering the difficulty I had in finding one of these clamps earlier this year, I can’t imagine how hard it will be now that the entire fleet has to replace them…. 
 

I have ONE as a spare at the moment, but all us Acclaim owners will need TWO if the AD goes through…

Now that turbo twin Cessna's have mandatory replacement of exhaust components, the parts are relatively cheap and available. Maybe the same will happen to these clamps.

[AeroEng]

56 minutes ago, N201MKTurbo said:

Now that turbo twin Cessna's have mandatory replacement of exhaust components, the parts are relatively cheap and available. Maybe the same will happen to these clamps.

Here’s hoping. I just looked up the equivalent clamp for a turbo Cessna 182 and it’s $250. A far cry from the $1250 clamp for the continental 550 turbo…

[kortopates]

Here’s hoping. I just looked up the equivalent clamp for a turbo Cessna 182 and it’s $250. A far cry from the $1250 clamp for the continental 550 turbo…

The spot welded clamps are much cheaper than the riveted ones. But if the proposed times in service stay as is, we’ll still pay about the same for them per hour since the spot welded one’s time out much more quickly at 1/4 the riveted ones.


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[AeroEng]

Understood and agreed. For the record, the $1200 beauty is definitely riveted. 

[Pinecone]

13 hours ago, N201MKTurbo said:

The AD addresses both spot welded and riveted clamps. The inspection interval is the same but the replacement interval is different. Spot welded 500 hours, riveted 2000 hours.

OK, I didn't read that far. 

But still, with Mooneys, most should have riveted clamps now.

[kortopates]

10 hours ago, Pinecone said:

OK, I didn't read that far. 

But still, with Mooneys, most should have riveted clamps now.

I wish that were true. But we can only use the approved part number for our engines and the TSIO-360's use a spot welded multi-segment V-clamp. It would be nice if this future AD inspires TCM to make and approve a riveted version, but given the relatively small number of them I am not optimistic. But I am not worried either, these things will last the life of the engine if they aren't abused and that's been the entire problem; folks haven't been paying any attention to them.  

[thinwing]

after looking at the pics...it is obvious the failing clamps have been abused with corrosion and are obvious poor shape.The spot wielded clamps i replaced during wastegate replacement had 1400 hrs on them ,atleast 2 prior installs and were still bright and shiny with no obvious wear or distortion.Mechanic thought i was nuts to replace them...but he had the riveted ones in stock..and I dont recall a huge price increase on the job.

[cbogie]

Has anyone found a source for the NH1009399-10 clamp? ACS still shows them as out of stock.

 

 

[jetdriven]

I placed an order with aircraft spruce and they sent me an email back after a week that said 110 day lead time, perhaps much longer, and I got to pay for it now.  
Yingling can get them from stock from textron, they have 10 in stock today, but they are $1680

[rickseeman]

WOW, I love turbos but I'm appreciating my Ovation today.

[231MJ]

I understand RAM sells a TSOed clamp that is reasonably priced.  Worth checking out.  

[AeroEng]

I received the same 110 day threat when I ordered mine. Then it shipped in a few weeks… ignore the warning and just order one - that’s my advice. Good luck.