Roger and al:  

So just to be clear and since it still bugs me about the SALA maintenance thing, here is the rule (law) found in the CFRs on Light Sport. 

14 CFR § 91.327 - Aircraft having a special airworthiness certificate in the light-sport category: Operating limitations.

We have to drop down to: 

(b) No person may operate an aircraft that has a special airworthiness certificate in the light-sport category unless—

(1) The aircraft is maintained by a certificated repairman with a light-sport aircraft maintenance rating, an appropriately rated mechanic, or an appropriately rated repair station in accordance with the applicable provisions of part 43 of this chapter and maintenance and inspection procedures developed by the aircraft manufacturer or a person acceptable to the FAA;

(2) A condition inspection is performed once every 12 calendar months by a certificated repairman (light-sport aircraft) with a maintenance rating, an appropriately rated mechanic, or an appropriately rated repair station in accordance with inspection procedures developed by the aircraft manufacturer or a person acceptable to the FAA;

Now for legal purposes the legal manufacturer is the company who signed off the FAA 8130-15 certificate of compliance and submitted this to the FAA.  Clearly it states inspection procedures developed by the aircraft manufacturer in multiple places.  It never stated any process for on condition and put all the responsibility on the OEM of record.  This then was changed by FAA legal without an change in the CFRs.  

I rest my case.  The thing has always been a mess because of overreach by the legal reading more into the CFR than was ever there.

Cheers

I love these debates. A great way to learn. 

Your quote on operating limitations is correct except Rotax or any other mfg can not require anything outside the FAR's.

You can't  just read part of a FAR. You must read everything in that particular FAR to the end. Reading only a partial FAR many times is misleading.

So the aircraft mfg can't require anything less or more than what the FAR's state. Many people relied on what some FAA person sitting behind the desk said. So FAA legal got involved. I tested three different FAA people in Oklahoma with the same questions and they all answered wrong and differently. When I quoted the correct FAR they got upset and ask why I ask if I knew the answer. I said because I wanted to know what they were telling people. So the the LSA FAA group (when it was together)  got their legal department involved. In two legal documents (2011 & 2013) it got cleared up. I've posted them before. Then to make sure the FAA was on solid ground they called the insurance companies about TBO and on condition. The insurance companies said they'd follow the FAA ruling.  The FAA says no aircraft mfg, engine or parts mfg can require anything above the FAA rules or give away the farm with less than the FAA rules and regs. If you read the FAR's through to the end it says you are allowed to use a program approved by the regulatory agency. Just like certified aircraft. The FAA told me and in its ruling that the approved program was on condition and the regulatory agency was the FAA. Two seperate letters from FAA legal in 2011 and 2013 back it up. So basically no one, but the FAA can make the rules and all mfg's must fall within the FAR's. MFG's can't  make their own rules outside the FAR's. All mfg's maint. and requirements must be within the FAR's. I know a few that have 3K - 4K hours on their engines. What do you think has happened to tens of thousands of engines mfg prior to 2008. They are all expired. They're still out there flying. So how many 912's are still out there since around 1990 til 2008 that are still being used.

Roger.  OK, just show me the on condition inspection for a Rotax engine that is approved by the FAA.  I have never seen one. 

Cheers

The FAA says it's Rotax's 100 hr / annual checklist. On condition is just a name given the procedure past the timed TBO. The on condition inspection must meet Rotax's checklist inspection or it won't pass. When I did my research project years ago on documentation and TBO and other approved methods the FAA said the Rotax inspection checklist is what you should follow since Rotax published this and wants everyone to follow it for every inspection otherwise they wouldn't have a published checklist. Plus I add an oil sample each annual. The approved program is called "on condition" and the specific items are the Rotax checklist which I have used since day one. This is what Rotax has published and its items are taught in Rotax classes. If the engine / aircraft passes all items on the checklist, all SB's are current and all tested items on the checklist meet the regular parameters then why would it be any different than an engine with less hours. If TBO was a major issue and people were crashing all the time by going past TBO then the FAA would not have an "On Condition" program that aircraft has been using for decades. If TBO was an an absolute failure point then Rotax is saying their engine's aren't as good as normal motorcycle and car engines. If the Rotax engine is prone to failing after the years or hours expiration then why isn't Rotax warning all the owners of such. Plus why and how are the tens of thousands of engines out there prior to 2008 having major issues or crashing. We both know there are tons of engines from 1990 and forward that are still out there flying. 

Like I stated before I know of several owners that are in the #k - 4K hour range and never had an issue, but they follow the Rotax inspections and use good preventive maintenance procedures. 

I'm just going by what the FAA told me and others years ago when we did an investigation into TBO and on condition. It was confusing for the normal FAA employee too because they weren't educated enough on the details. So they got the FAA legal department involved. They are the final word over everyone else.

Rotax makes an excellent engine that is durable and solid. So providing you do all the normal Rotax maint., follow the SB's, stay up on preventive maint. and don't do anything to damage the engine then it's a good dependable engine. Look at all the ones around the world and all the ones that are older than 2008 that are flying around the world.

Rotax is a good trustworthy engine.