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12 year mandatory overhaul

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The recommended FD mechanic in Iowa asserts that FD requires engine overhauls at 12 years irrespective of condition or hours. This is the first I heard of such a requirement and I read this blog regularly. I was told 1500 TBO and nothing else. Has anybody else heard of such a requirement and was anyone told about this requirement when they bought from FD??  I have not seen anything on this blog but I understand this is the same concept as the 5 year hose change. I understand if FD dropped the language that we must follow rotax directions the problem (and fraud) would go away. Looking for everyone's thoughts

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CT4ME   

No expert here, but all I've heard is 15 year TBO, or the 1500/2000 hour TBOs.   The 12 yr number may have been very early in the life of the 912.  Most older engines can be upgraded to 2000, with little effort or cost.  I believe you can go to "on condition" inspection, and exceed all of the aforementioned TBOs.  Provided that the engine and gearbox have been well-maintained, 3,000+ is possible.   And there is the hose change issue...

Of course, rather than an overhaul, some advocate just getting a new engine and selling the old one, recovering much of the cost.

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This all goes back to Rotax wanting a 1500 hr/12 yr or 2000 hr /15 year overhaul. It's good money at approximately $13K.

Let's put this in it's final grave.

Rotax or FD CAN NOT make policy over and above what is in the FAR's. The FAA legal has ruled on this twice that I know of years ago and you are allowed to go on condition just like GA aircraft. The FAA also checked with the insurance companies and they said they would abide by what the FAA rulings are and their decision.

 

Go on condition and don't lose any sleep over this anymore. If people still want to argue, don't. Just tell them to call Edsel Ford at the FAA.

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TheFD recommended A&P says the FAA flight standards office also asserts that the legal letters do not mean the 12 years is not mandatory but require an approved alternate maintenance program.  The A&P won't approve after 12 years and says the CT will not be certified. I'm also bothered that at sale I was told 1500 TBO. Since then I heard and upgraded to the 2000 on condition. FD should have represented 1500hrs/12 years but only 1500 TBO. I'm wondering if FD told anyone 12 years.   I consider the single limitation of 1500hours as a material misrepresentation to a class of buyers. And, as I understand it, the problem can be fixed by FD merely changing the POH to not require compliance with Rotax requirements 

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"The A&P won't approve after 12 years and says the CT will not be certified.'

Sorry he's wrong. FD or Rotax has nothing to do with this. They do not make the rules. It is a FAR and they have an alternate program. Called on condition which also means it just has to meet its existing standard of operation. The FAA carries more weight and makes the rules. Not an A&P, Rotax or FD. 

Find as new A&P if he fails to do his due diligence in his research.

It's a shame some will spend $13K  for nothing.

 

It has nothing to do with FD saying follow Rotax requirements. Rotax or FD still can not make rules over and above what is already in the FARs. They can write the world, but it may not carry an legal weight.

 

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Anticept   

The 5 year rubber replacement is technically on condition too, but the issue is, we've SEEN multiple failures as a result of NOT completing it, and it was a result of age deterioration. That's not something I would recommend doing "on condition."

We KNOW rubber fails, we just don't know when. By the time we find out, there's a good chance there's a serious problem.

In some piper aircraft, certain hoses have a life limit as dictated by an AD, 7 years, because of failures in the field from deterioration.

 

As for this "mandatory" overhaul interval: mandatory overhauls are not in the ASTM, and are not a safety of flight issue. The airframe manufacturer must issue a Safety Directive to enforce it. Even still, you can go to the FAA and could get an exemption from such an SD on the aforementioned basis. It's in the FAA's mandate that regulation and enforcement must be in accordance with flight safety, and giving manufacturers this power to dictate what is and isn't safe without just cause would be an attempt to sidestep this mandate, and I'm certain that would be in violation of provisions in the Administrative Procedures Act.

The fact is, overhauls are a *precautionary* maintenance procedure, based on a little bit of pixie magic and on a super conservative estimates... aka "we guess it will last this long under the harshest conditions".

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Runtoeat   

Eagle Wings, not sure if you've read the following thread. This might provide you with the needed documentation to show your A&P he needs to better understand the FAA's rules for accepted methods for maintaining engines.  Based on the referenced FAA Office of General Council legal intrepretation letter found in the link below, the Rotax TBO can only be a suggested method for maintenance for your engine unless the manufacturer of your aircraft specifically puts this in writing in the section of your Aircraft Operating Instructions which gets FAA's approval and signoff.  Our Flight Design aircraft have no such section in the AOI.  Until the manufacturer provides proof to the FAA that this TBO is a safety concern and convinces the FAA that the TBO must be made mandatory to eliminate these safety concerns, without regard to other acceptable methods for maintenance (which the FAA allows), and the FAA agrees and it issues a TSB or some other regulatory FAA document making the TBO mandatory, it is not mandatory.

http://ctflier.com/index.php?/topic/3663-rotax-tbo-please-read/&

 

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People get all heated up about this, because we are talking about an engine.  But really an engine is just another manufactured component of an aircraft.  The maintenance schedules for an aircraft are set by the manufacturer, not the individual component builders.  If the latter were the case, it would be a maintenance and regulatory nightmare trying to keep up with maintenance schedules for brake pads, wiring, individual hoses, tires, hardware like nylock nuts, and the thousands of other components that make up an airplane.  Many of them have manufacturer-recommended time or wear limits, and none of them are enforceable unless FD includes them in its maintenance schedules.

Flight Design has wisely chosen to remain silent on the 12yr Rotax overhaul and not include it in their maintenance schedules, leaving it up to the owner to decide.  In reality, how many people would by a CT if they knew they were required to spend $13k every 12 years in addition to the other maintenance required on it?  I don't know of any LSA manufacturer that enforces the 12yr limit, though I'm sure there are one or two out there.  

 

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One thing to remember in all this Rotax nor an aircraft Mfg can set rules or policy over or under what the FAA has in place. The FAA says you can go on condition and they also checked with the insurance companies and they said they would follow what the FAA had in place.

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1 hour ago, FlyingMonkey said:

People get all heated up about this, because we are talking about an engine.  But really an engine is just another manufactured component of an aircraft.  The maintenance schedules for an aircraft are set by the manufacturer, not the individual component builders.  If the latter were the case, it would be a maintenance and regulatory nightmare trying to keep up with maintenance schedules for brake pads, wiring, individual hoses, tires, hardware like nylock nuts, and the thousands of other components that make up an airplane.  Many of them have manufacturer-recommended time or wear limits, and none of them are enforceable unless FD includes them in its maintenance schedules.

Just to be clear nylock nuts are covered in the maintenance manual. They are supposed to be replaced if they are removed.

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20 minutes ago, Tom Baker said:

Just to be clear nylock nuts are covered in the maintenance manual. They are supposed to be replaced if they are removed.

I meant on time.  I was just citing examples of things that *could* be time-limited, and would cause huge maintenance headaches, I was not making claims of whether any of those things actually have any maintenance schedules.  I was speaking hypothetically.  

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Runtoeat   

I have learned a lot about "mandatory" claims since getting into this.  My mechanic, who often has "discussions" with his FSDO friends and who has worked on turbines thru Franklins and fixed wing thru rotary wing the past 40 years has helped me understand the various forms of paperwork that an aircraft's airworthiness is based on.  He has reviewed with me those sections on the Aircraft Operating Instructions where there is a definite section with entries that spell out mandatory maintenance and this section will be signed by the FAA.  He has also reviewed with me various TSB's and Safety Alerts which spell out what the FAA mandates the owner/operator must do to maintain the airworthiness of a aircraft.  I am confident that the Rotax TBO can only be a suggested method for extended maintenance of one's engine and that the "other methods of maintenance found acceptable by the Administrator" is an option that the owner/operator of engines used under Part 91 is permitted to use.

Tom, would the direction to not re-use lock nuts be considered "best practice" by the industry and thus be generically a "mandated" item rather than considered a "mandated" item because it is in the Rotax maintenance manual?

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34 minutes ago, Runtoeat said:

Tom, would the direction to not re-use lock nuts be considered "best practice" by the industry and thus be generically a "mandated" item rather than considered a "mandated" item because it is in the Rotax maintenance manual?

When I was building a Sonex, there was quite a controversy on nylon lock nuts in the community.  Some builders said NEVER re-use them.  The factory guidance was that it was acceptable to re-use a lock nut 2-3 times, with the test being that if you could turn the nut at all by hand it was time to replace it.  I usually replaced nuts that had come off, but if it was a fresh nut that had not been threaded more than once, I sometimes re-used them.

In a critical structural or control application, I would replace. 

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Runtoeat   

Andy & Tom.  I have been of the opinion that a nyloc nut can be reused 2 to 3 times or until one could turn it by hand.  I am more knowledgeable about this due to Tom's link but I didn't find anything below 7/16" in the charts for min torque. I know there's charts for metric but didn't take the time to look these up.  Thanks.

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