Auf "COPA" gerade ein großes Thema: Die "Mandatory SB" MSB05-8B von TCM

Betrifft den Nockenwellenantrieb fast aller Einspritzversionen der 470-,520-, 550-Serien ... praktisch jeder Motor, der vor August 2005 gebaut (und seitdem nicht vom Werk überholt wurde etc.), ist betroffen.

Soweit man hört könnte diese SB demnächst eine AD werden. Angeblich sind mindestens drei Motorschäden an SR22 auf ein Schaden am Nockenwellenantrieb zurück zu führen, der mit dieser SB in Verbindung steht.

(Mein Triebwerk wurde 2006 gebaut ... offenbar habe ich Glück)

Hallo Alexis,

hast Du Dich da nicht um ein Jahrzehnt vertan?

Grüsse Sebastian

Klar .... 2006! Sorry

Hier ist der Link zum SB.

https://www.tcmlink.com/pdf2/MSB05-8B.pdf

Gilt also auch für alle Bonanzas.

Oder doch 2005? Das Service Bulletin stammt ja mal von 2005/08/09!

Eine interessante email erhielt ich zu diesem Thema von Mike Busch, Zitat:

Das ist auch auf Beechtalk ein großes Thema. Natürlich.

Hier der Post von Matt Anker - Das war der mit der engine failure von der Mike Busch spricht. Lucky he can talk about it. Engine Failure in IMC, und es zur nächsten Piste geschafft.

Er hat jetzt sozusagen sein eigenes AD, Zitat "Good thing I have a sense of humor. Better to have your very own AD than a place in a NTSB report."

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"I received a phone call from my friendly CMI air safety investigator this afternoon regarding my engine failure back on December 26th, 2015. This was off the record, verbal stuff, to keep their legal department happy.

Reference the original thread:
https://www.beechtalk.com/forums/viewtopic.php?f=41&t=117010

The initial investigation was contained in that thread:
https://www.beechtalk.com/forums/viewtopic.php?f=41&t=117010&start=237

I didn't feel like resurrecting it in CrashTalk.

So in summary, to those late to the game, or those who haven't read Nate's e-book, I had an in flight engine failure in a 2001 CMI zero-timed IO-520-BA because the cam gear shed about 3 teeth, then promptly proceeded to machine clearance out of itself where the cam shaft stopped turning. My P/N was 655516A. You can go to the thread referenced above to see all the gory pictures.

The new revelation today was that the metallurgical analysis revealed that the gear failed "in fatigue" and that there were no metallurgical defects found.

Now here's what's going on in the background with the FAA ACO regarding the failure. . .

CMI has a new cam gear called the 656818 with a wider face that must have come out in 2009, and has zero Service Difficulty Reports (SDR) against it. The one previous to it is the 656031, which presumably came out in 2005, has 2 SDR against it for premature wear and tooth shedding. Prior to that were the 655516 and 631845 which all have failure history.

In 2005, revised in 2009, CMI issued the service bulletin SB 05-8A specifically covering these gears, and calling for them to be retired at overhaul or any time the case is split.
https://www.tcmlink.com/pdf2/SB05-8A.pdf

Depending on how many failures can be linked to these parts, and the extent of the carnage, you could see an AD on this in the future. This would target inspections on engines built during a specific data range that have not shown compliance with SB05-8A targeting specifically the cam gear or SB97-6B which specifies mandatory parts replaced at overhaul. There typically isn't any logbook data specifying which gear is installed. I suspect the suspect gears could be identified by inspection with the starter adapter removed to allow measurement.

To be very clear. . . . I'm not personally lobbying for any airworthiness directive on this matter. I'm not dead, my overhauled engine no longer has the affected part.

However, if you have an engine that may have this gear, you might think twice about stretching past TBO. The fact that fatigue cracks are occurring is a very scary design flaw, and it gives zero warning (like making metal). It's clearly known to CMI, and a matter of time before a FAA cost-benefit analysis could turn it into an AD. Make of this what you will."

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Dieser Post stammt vom Juli 2016, und Matt sieht das mögliche Eintreten einer AD ja bereits voraus. Der Rest der Gespräche sind im Wesentlichen Fragen, ob nicht TCM hier liable ist.

Aber alles in allem schon krass.

Bitte korrigieren - 2005 nicht 2015!!

Done!

https://www.planeandpilotmag.com/article/all-about-the-ad-that-never-was/

Bei der ganzen Geschichte geht mein Bullshitanzeiger in den roten Bereich ;)

From avweb

Continental Motors is working with the FAA to dispel what they see as confusion and unnecessary concern about a mandatory service bulletin (MSB) issued by Continental Motors in early 2017 for a camshaft gear found mostly in older IO-520 and IO-550 engines. Several GA groups, including AOPA, the American Bonanza Society, COPA, Twin Cessna Flyer, and Savvy Aviation were sufficiently exercised about MSB05-08B that they requested an audience with the FAA without inviting anyone from Continental. A Continental representative called that decision disappointing and said it was “bizarre that a meeting was organized with the FAA [on this topic] without including Continental.” Continental was particularly bothered by an assertion made by Savvy Aviation, among others, that Continental had requested an Airworthiness Directive be issued for the part, possibly in an attempt to gouge consumers on replacement parts. In an email Continental shared with AVweb, the FAA confirmed that Continental had not requested an airworthiness directive and that MSB05-08B was prompted by a request from the FAA to conform the Service Bulletin to a format suitable for adoption as an AD.

Continental tells AVweb they are seeking FAA approval to make three changes to MSB05-08B in order to minimize compliance costs for operators. First, the camshaft gear can be inspected without significant disassembly by removing the starter. Continental is proposing that the part be inspected periodically and continue on condition if no damage is found. Second, Continental is proposing that the engine not be subject to a mandatory overhaul time period—though they continue to recommend overhaul after 12 years. Third, Continental will publish instructions for replacement of the camshaft gear that do not require engine disassembly. The MSB, and the AD likely to be released by the FAA, apply only to Continental engines using a camshaft gear last made by Continental in summer of 2005, so any engines built after August 2005 or overhauled since August 2005 in accordance with Continental’s Service Bulletins are unaffected.

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Two things, last sentence is your answer to the overhaul questions. As I follow this carefully, trying to buy a plane, how does one verify the SBs were followed, when overhaulers and cont. rebuilds use old parts that are tested to be fine for reuse. Best I can figure out, is pull starter at inspection and look at the number on the gear, seems invasive but I'm going to insist on it at a prebuy.

And two, not including continental in the above meeting was not cool, that's not how things get worked out.