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A question about AD's

Except, if the engine were maintained properly in accordance with part 43 by an appropriately licensed mechanic your example would not be true. If you altered that engine in some manner which raised some question then ??? It's in the record keeping and who does what to it.

The FAA says that's not true. See my previous post about the aircraft (including the installed engine) not being subject to 14 CFR Part 43. That means that there is NO record keeping requirement for maintenance or repair that is performed by a non-certificated individual, there is no way for anyone to verify that the records that are there are complete. Just the mere possibility that the component can be legally maintained by a non-certificated individual casts the entire component into question as to whether is has or has not had such maintenance or repair completed. Since nobody knows for sure, nobody can "certify" that the component meets the TC. Once the component (engine, prop, etc) has been installed and operated on an experimental aircraft it is an experimental product until such time that it has had a conformity inspection done under controlled conditions and properly documented.

Now, of course having said all that, If there is a certificated mechanic that is willing to put his signature on a statement saying that the component does in fact meet its TC after being installed and operated on an experimental aircraft, then I guess all is well. Hopefully that wouldn't come back to bite that individual someday down the road. Forewarned is forearmed.
 
Now, of course having said all that, If there is a certificated mechanic that is willing to put his signature on a statement saying that the component does in fact meet its TC after being installed and operated on an experimental aircraft, then I guess all is well. Hopefully that wouldn't come back to bite that individual someday down the road. Forewarned is forearmed.
Isn't that what I said using different words?
 
Back to the original idea- an AD that specifies an airframe or series of airframes applies only to those airframes, even though somebody may have approval to use parts from those airframes on some other aircraft. The guy with the tailfeathers would do well to do what the AD says, but unless the AD says so, it is limited to those airframes/components/ engines specified.

oh, yeah - Opinion.
 
I used to own a C150/150 with the Texas Taildraggers (formerly ACT) 320 conversion (now owned by DelAir).
There was an AD on the Avcon muffler used for some 320 conversions, applicable (or not) to specific Avcon conversion kit serial numbers.
The previous owner's mechanic noted "AD not applicable due to Avcon kit not being installed".
However, right on the muffler's tailpipe was a big old Avcon data plate!
I checked the parts list in the STC paperwork-- yep, an Avcon muffler was listed.
And sure enough, the muffler cracked out at the outlet--
just like the AD warned about.

So even if maybe technically / legally not applicable,
it's probably a good idea to pay attention to those ADs.
 
If the AD says “Avcon Muffler” then it applies to Avcon mufflers. If it says “Piper Aircraft with Avcon mufflers”, then no matter how important to safety of flight, it does not apply to Cessnas with Avcon mufflers.

As to mechanics who make mistakes with ADs? I know of one large FAA repair station that missed Mooney ADs for almost 20 years in a row! We had a Super Cub with only one muffler inspection in 800 hours! Owner likes a different shop each year, so it wasn’t just one mechanic. When I got to do the ninth annual, it received a brand new Atlee muffler.
 
If the AD says “Avcon Muffler” then it applies to Avcon mufflers. If it says “Piper Aircraft with Avcon mufflers”, then no matter how important to safety of flight, it does not apply to Cessnas with Avcon mufflers...…

As I recall, the AD didn't apply to all Avcon mufflers, just the ones supplied with an Avcon engine conversion kit in a certain s/n range.
"Applicable to Avcon kit s/n xxx through s/n XXX" or similar wording.
Kinda like the situation cited in post #1--
does an AD for PA18's pertaining to the rudder apply to the PA18 rudder fitted to your PA12, PA22, or homebuilt?
Both yes and no could be argued-- as per this discussion.
 
I disagree. An AD is a legal document. You either do it or you are in violation - but it is not binding on any component outside the specified group or serial numbers.

If you are arguing common sense or safety that is different. Sure, do it, and you must make a logbook entry. "AD --- does not apply to this component. The requirements of AD --- have been met by ---." But you are not legally required to do so.
 
By the way, all my aircraft have complete lists of ADs. Even the Nelson crankshaft ADs are listed, even though I have no Nelson crankshafts. The latest lift strut ADs are there - "previously c/w". I believe that is now necessary.
 
If you are arguing common sense or safety that is different. Sure, do it, and you must make a logbook entry. "AD --- does not apply to this component. The requirements of AD --- have been met by ---." But you are not legally required to do so.

Wrong !!!!!!!!
You can not take a possibly defective part out of an airplane that falls in the s/n range and put it in an airplane that is outside of that s/n range or a different model. So it does apply to the component. Conversely if you did it before the ad was issued, it would still apply to that component.
 
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I disagree. An AD is a legal document. You either do it or you are in violation - but it is not binding on any component outside the specified group or serial numbers. If you are arguing common sense or safety that is different. ....

That's where I was coming from, guess I didn't make myself clear.
IMHO (and the opinion of the previous owner's IA) the Avcon muffler AD did NOT apply to my airplane,
but it was a good idea to check the it anyways.
FWIW I had the muffler overhauled, they rebuilt it with beefier material which made it less probe to cracking.
 
Wait until you have to start dealing with Rotax engine failures in light sport airplanes. We have 35 light sports at work and we have had 4 in flight failures of valve retainers and know of several others. The ntsb and the faa is aware and there will be no AD issued because the engines meet astm specs, they are relying on rotax to solve the issue and looking the the other way. Rotax denies any problems with the valve retainers but they have been checked for hardness and there is a 3 month period where they don’t meet spec.

Oh and light sport airframe manufacturers can create their own equivalent versions of AD’s that are mandatory to be complied with if the operator wants to be legal to fly. More weird and convoluted rules. YMMV, Tim
 
Can you tell us more about the Rotax retainers? What is the 3 month period and how many hours on these engines?
 
I know that there was between 600 and 1900 hours on the engines at work that failed, I was not told what 3 month period, just that the NTSB was narrowing it into a narrow 3 month window of when the retainers were made. I did help put 2 of our airplanes back together, they pulled 3 of them out of fields and swamps when they failed, one was in the pattern and made a precautionary landing. Makes a real ruckus from what the pilots describe when they let go. I like to stick with the Lycoming's.

Some of our airplanes put on about 100 hours per airframe per month even with the enrollment being down some right now because of Covid. These kids can come out with a commercial/CFII/MEII in 10-12 months if they apply themselves and choose the path they want to take and the light sports we have are affordable simple and overall safe options to get hours. This aggressive of a program can sure put on the hours quick. Tim
 
Wait until you have to start dealing with Rotax engine failures in light sport airplanes. We have 35 light sports at work and we have had 4 in flight failures of valve retainers and know of several others. The ntsb and the faa is aware and there will be no AD issued because the engines meet astm specs, they are relying on rotax to solve the issue and looking the the other way. Rotax denies any problems with the valve retainers but they have been checked for hardness and there is a 3 month period where they don’t meet spec.

No manufacturer or manufacturing process is perfect. Bad parts from suppliers (or even bad internally produced parts) sometimes make it into production series engines. But it's not like Lycoming and Continental haven't had their fair share of this type of issue as well... There have been more than a few defective cylinders, crankshafts, camshafts, valves, rocker arms, etc. that made it into production from those companies, as well as their aftermarket suppliers.

And when those parts start failing in the fleet, the first reaction of EVERY vendor is to deny it's a problem, even while the research the issue behind the scenes. How long did Champion refuse to acknowledge the problems with their spark plug resistors before quietly redesigning them to solve that issue? No manufacturer wants to be perceived as going off half-cocked and grounding half the fleet when those first few isolated reports start coming in about a problem. But eventually, the good companies will accept reality, and pursue a solution. Unfortunately, most of us (owners) still get stuck with the tab for fixing the problems!

I beileve ANY engine manufacturer CAN have a problem. If I were picking on Rotax, I'd be calling them out for the carb floats that they keep replacing with new versions, only to have those "sink" as well. Thank goodness Marvel Schebler has finally released some aftermarket floats that are getting good reviews!

It sounds like in the case you're referring to that Rotax may have gotten a bad batch of valve retainers (either from a vendor or their internal parts production process) and that they are still working to figure out the failure pattern so they can determine which engine lines and serial numbers were impacted. I would fully expect to see a mandatory "Service Bulletin" (as close as you get to an AD in the ASTM-approved world, and still "mandatory" for those aircraft issues S-LSA airworthiness certificates) when they get it figured out.

Regardless of this potential valve retainer issue, I believe that a higher percentage of Rotax engines make it to TBO than do Lycoming or Continental engines... But that's based on 2nd-hand information from shops that are rebuilding them, and not personal experience. My personal Rotax 912ULS has just over 100 hours towards a 2000-hour TBO, so it's just a baby!
 
Good luck In getting the floats approved for a light sport, only the airframe manufacturer can over ride rotax for an approval and I have not heard of anyone doing that yet. Even if marvel gets them stc’d they are still not allowed under the light sport rules... which was the point of my post, about how the rules are different than either experimental or certified and the FAA doesn’t want to deal with anything slsa. Tim
 
What's wrong with going back to brass floats? Easy to check for leaks, dab of solder will do ya. Is it the ethanol? Rotax uses Bing carbs, before 1970 they were brass.

Some ASTM mfgs recognize the foolish restriction on things like instruments. If your airspeed is no longer manufactured, you have to get permission to replace with something different, even if TSO'd. Some let you fill out an online form and pay $50, done.
 
Good luck In getting the floats approved for a light sport, only the airframe manufacturer can over ride rotax for an approval and I have not heard of anyone doing that yet. Even if marvel gets them stc’d they are still not allowed under the light sport rules... which was the point of my post, about how the rules are different than either experimental or certified and the FAA doesn’t want to deal with anything slsa. Tim

Actually that's not quite true... There are multiple types of aircraft that qualify under the Light Sport rule. Only S-LSA (Special - Light Sport) fall into the category you're talking about. And those aircraft do require the use of an ASTM certified engine (a Rotax 912 UL, for instance).

Other Light-Sport compliant aircraft may be registered as E-AB (experimental amatuer bult) or E-LSA (experimental - operating as light sport). Those "experimental" types no longer have to comply with the manufacturer's standards, though they do still have to comply with the overall Light Sport restrictions (2 seats, fixed gear and prop, 1320 lbs max gross, etc.). As an "experimental" airplane, they could either have a Rotax 912 UL or the "non-certified" version, the 912 ULS, and since the owner now assumes responsibility for maintaining airworthiness, they came make any modifications they choose to the aircraft (as long as they stay within the LSA rules). There are plenty of experimental Light Sport type airplanes out there with seriously "hopped up" Rotax engines (Edge, Zipper, etc.).

Any S-LSA owner can request to have their aircraft re-certificated in the E-LSA category (there's some FAA paperwork, but it's pretty routinely done). Once that happens, the aircraft can no longer be rented out for instruction, used for glider towing, or any other purpose other than personal use. (That's slightly over-simplified, but directionally accurate.)

Even Rotax themselves are much more liberal about the "rules" for their non-certified engines (912ULS, versus the certified 912UL - both 100 HP virtually identical engines other than the certification rules). You can make changes that Rotax doesn't approve, but it may void your warranty (if any). They just don't have any "say" over the non-certified engines.

It's a lot like if you were to install a certified Lycoming in an experimental. If you make even one modification that takes it out of compliance with the type certificate (or fail to comply with a single AD), it's no longer considered to be a "certified" engine, and you would need to have an IA certify that it is back in compliance (every single part and specification matching the TC) with the engine's Type Certificate before it could be used again in a certified airplane. And while that might be theoretically possible, in reality it is both financially impractical and highly unlikely that you'd find an A&P/IA willing to sign off that EVERY part is TC-compliant...

As you might have guessed, my airplane is E-LSA, my engine is a Rotax 912ULS, so the MS floats are perfectly fine for me to use. (I haven't done it yet - waiting until my existing floats "sink" before replacing them.)
 
And then there is the CLSA, which allow tso’d parts, stc’s and all of the normal certified rules...including AD’s
 
What's wrong with going back to brass floats? Easy to check for leaks, dab of solder will do ya. Is it the ethanol? Rotax uses Bing carbs, before 1970 they were brass.

Some ASTM mfgs recognize the foolish restriction on things like instruments. If your airspeed is no longer manufactured, you have to get permission to replace with something different, even if TSO'd. Some let you fill out an online form and pay $50, done.

Well Marvel had a problem with them popping and sinking caused cycle fatigue with altitude changes which is why the went away from brass floats.
 
And then there is the CLSA, which allow tso’d parts, stc’s and all of the normal certified rules...including AD’s
I am unaware of an aircraft category called "CLSA" unless you're referring to a standard type-certified aircraft that otherwise meets (and has continuously met) the requirements for operation by light sport pilots. An example would be an original J3 Cub. And, yes, those standard type-certified aircraft that qualify for operation by light sport pilots must still comply with all the normal maintenance regulations, to include AD compliance, that apply to any other type-certified aircraft.

But for the record, those are NOT "Light Sport Aircraft" and have never been.
 
I am unaware of an aircraft category called "CLSA" unless you're referring to a standard type-certified aircraft that otherwise meets (and has continuously met) the requirements for operation by light sport pilots. An example would be an original J3 Cub. And, yes, those standard type-certified aircraft that qualify for operation by light sport pilots must still comply with all the normal maintenance regulations, to include AD compliance, that apply to any other type-certified aircraft.

But for the record, those are NOT "Light Sport Aircraft" and have never been.

The FAA lists 131 aircraft models as Certified Light Sport Aircraft https://www.faa.gov/aircraft/gen_av/light_sport/media/existingmodels.pdf
 
The FAA lists 131 aircraft models as Certified Light Sport Aircraft https://www.faa.gov/aircraft/gen_av/light_sport/media/existingmodels.pdf
Yep - those are the standard category, type certified aircraft that meet the requirements to be flown and operated by a Light Sport pilot. While they do meet the eligibility rules to allow them to be flown by Light Sport pilots, they are NOT "Light Sport Aircraft," per se. The link on the FAA page where you found this list is somewhat incorrectly labelled as "Light Sport Aircraft: Existing Type Certificated Models." It should have been called "Light Sport Eligible Aircraft: Existing Type Certificated Models."

I stand by my observation that there is no FAA classification of C-LSA. The two types of LSA are "Special - Light Sport" and "Experimental - Light Sport." You can read more about it in the "Buyer's Guide" on the same FAA web page where you found the list of certified aircraft that meet the eligibility rules for Light Sport pilots to fly. Here's that link: Light-Sport Aircraft Buyer's Guide.
 
I stand by my observation that there is no FAA classification of C-LSA. The two types of LSA are "Special - Light Sport" and "Experimental - Light Sport."

You are correct Jim. From the standpoint of aircraft certification, there are two categories called out as "light-sport aircraft". There is the "light-sport" category certificated under 14 CFR 21.190. These are the factory-built aircraft commonly called "special light-sport" because they are issued a special airworthiness certificate in the light-sport category. These are built under the ASTM standards and are sold ready to fly.

The other light-sport category is an experimental purpose called "operating light-sport aircraft" certificated under 14 CFR 21.191(i). There are a couple of ways that an aircraft can end up in this category, but the aircraft will meet the LSA definition in all cases.

There are many other aircraft that are "sport pilot eligible" because they meet the definition of a light-sport aircraft as called out in 14 CFR 1.1. However, it is a bit of a misnomer to refer to these aircraft as "light-sport aircraft" because that term does not appear anywhere on their official FAA paperwork. These can be certificated in a number of categories, but none will be certificated as "light-sport aircraft" even though they meet the definition. The maintenance rules for these aircraft remain the same as before the LSA rules were codified.

The FAA caused all this confusion when they continued to refer to these aircraft as "light-sport aircraft" instead of "sport pilot-eligible" aircraft, and that confusion remains to this day. I doubt that will ever change.
 
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