Required Service Bulletins For Experimental Aircraft

Daleandee

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Dale Andee
The question has been asked on other forums about whether there is a legal requirement to follow Service Bulletins that are given for an experimental aircraft/engine. FWIW, I think it's very wise to keep current with Service Bulletins that are issued. The engine on my aircraft has received a couple of "Safety Alerts" and Sonex calls the theirs "Service Bulletins" that pertain to my airframe.

Let me say upfront that I agree with the logic behind their latest Service Bulletin and that my plane is already compliant (it was when built 10 years ago). But it seems that what they are giving now is a bit outside of the purpose of a Service Bulletin. How the pilot sets up the cockpit in their airplane build is the builder's decision. Reading the attached Bulletin should help you understand what I'm driving at:

upload_2022-6-4_19-33-20.png

Again ... I agree with the logic but this seems to infringe on the freedom of the builder especially when putting it up as a "required" Service Bulletin. Seems a stretch to me ...

(edited for clarity)
 
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My lancair has a number of service bulletins. Only one of those is stated to be mandatory by the bulletin. Service bulletins are not mandatory to my knowledge. Does verbage in the service bulletin stating it's mandatory override the non-mandatory nature of a service bulletin?
 
Does verbage in the service bulletin stating it's mandatory override the non-mandatory nature of a service bulletin?

I don't believe it can as, from my understanding, experimentals are not bound by these bulletins and alerts. But that debate isn't settled. FWIW, I do follow and conform to all Service Bulletins and Safety Alerts that apply to my plane.
 
Yup, same here. All SB's are complied with on mine also. Some at eash annual.
 
legal requirement to follow Service Bulletins that are given for an experimental aircraft/engine
FWIW: there is no existing legal framework that mandates OEM bulletins on E/AB or TC aircraft. The only way an OEM bulletin becomes mandated is when a FAA rule includes that bulletin like with an AD note. Should these OEM bulletins be reviewed by each owner? Yes.
 
FWIW: there is no existing legal framework that mandates OEM bulletins on E/AB or TC aircraft.

I didn't state that correctly. My bad. What I meant to say was that on other forums there was a discussion about whether it was a legal requirement or not (I edited the OP to clarify). I don't believe that it is but there are some that insist it may be. One argument comes from those who have placed a certified (or previously certified) engine on their experimental aircraft.

The bigger debate is from those who say that while 14 CFR Part 43.1(b)(1) states that Part 43 doesn't apply to experimentals, what does apply is 14 CFR Part 91.417 (a) (2) (V) i.e. the AD or safety directives cited. As I said, I'm not convinced but others are. I comply because it's wise to follow the guidance of the engineers and designers.

Clear as mud ... :)
 
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What I meant to say was that on other forums there was a discussion about whether it was a legal requirement or not. I don't believe that it is but there are some that insist it may be.
I had thought this general topic had been put to rest when the FAA clarified the AD applicability to E/AB aircraft a number of years ago. Sounds like the old arguments have been applied to bulletins. “Legal requirement” implies there’s a rule to break. What rule? 91.417 above doesn't as it dont apply to OEM bulletins. Even when the ADs were in the mix there was no specific rule requiring them. One possible violation I recall was that not complying with the AD (or bulletin?) violated the E/AB airworthiness standard of “condition for safe operation.” Maybe this is what they are using for the bulletins?
One argument comes from those who have placed a certified (or previously certified) engine on their experimental aircraft.
FYI: Once a TC’d engine or propeller is installed/operated on an E/AB aircraft it no longer conforms. And once installed any engine requirements revert to the E/AB ops limits. So the TC part of the engine no longer has a bearing on the matter. As you said... clear as mud.
 
A pilot can not still use one hand for the stick and the other for the throttle, with the center mod?
 
FYI: Once a TC’d engine or propeller is installed/operated on an E/AB aircraft it no longer conforms. And once installed any engine requirements revert to the E/AB ops limits. So the TC part of the engine no longer has a bearing on the matter. As you said... clear as mud.
I recall hearing once (I believe at a presentations at OSH) that if you put a TC'd engine in your E/AB aircraft but you leave the dataplate on the engine then you have to follow any AD's issued by the engine manufacturer. But if you remove the dataplate, then you are not required to.

I'm not one of those guys who reads FAR's and such for sport so I can't vouch for the accuracy of that viewpoint.

On my plane, if Continental issued an AD for my engine, I followed the AD.
 
I recall hearing once (I believe at a presentations at OSH) that if you put a TC'd engine in your E/AB aircraft but you leave the dataplate on the engine then you have to follow any AD's issued by the engine manufacturer. But if you remove the dataplate, then you are not required to.

I'm not one of those guys who reads FAR's and such for sport so I can't vouch for the accuracy of that viewpoint.

On my plane, if Continental issued an AD for my engine, I followed the AD.
very gray area. without a data plate, the engine is what ever you want to call it so yes the AD would not apply since it is not a xxxx model yyyy anymore. with the data plate still on, it is a very debated question. last time I heard the FAA takes the position that it is still a xxx model yyy and the AD will apply. the problem comes in when the AD is about something that is no longer installed on the engine. IE a magneto drive gear for example, that part may be long gone on an exprerimental, so do you need to log the AD as N/A even though there is nothing in the AD saying that you can? again, clear as mud. me personally, i just do the AD the engine does not know that its on an experimental now.
 
Again ... I agree with the logic but this seems to infringe on the freedom of the builder especially when putting it up as a "required" Service Bulletin. Seems a stretch to me ...

Reeks of CYA -- did someone skoosh a sonex and it was blamed on cockpit ergonomics and this sort of split-handed operation?
 
FWIW: there is no existing legal framework that mandates OEM bulletins on E/AB or TC aircraft. The only way an OEM bulletin becomes mandated is when a FAA rule includes that bulletin like with an AD note. Should these OEM bulletins be reviewed by each owner? Yes.

Just making this part more obvious since I think a lot of people don't realize it. Even on certified aircraft, "mandatory" SB's are not mandatory to airworthiness (unless there is a related AD involved).
 
I recall hearing once (I believe at a presentations at OSH) that if you put a TC'd engine in your E/AB aircraft but you leave the dataplate on the engine then you have to follow any AD's issued by the engine manufacturer. But if you remove the dataplate, then you are not required to.
That was one of a number of "exceptions" out there concerning ADs and E/AB aircraft which led them to clarify the guidance. You'll find under the updated guidance the AD applicability statement will determine what is covered and if it is applicable to TC or non-TC aircraft. AC 39-7 goes into more detail with examples. So whether you keep the data tag or not, its the action of installing and operating the engine on an E/AB that is the qualifier.

In general terms, the certified side is a "closed system" where everything is connected in some fashion from the birth to death of an item. Anytime an item leaves that closed system, i.e., TC engine on an E/AB, that item loses its "certified" status. In the this case since anyone can work on an E/AB regardless if it has a data plate or not the engine no longer conforms to its TC. So in order for that now E/AB engine to rejoin the certified world it would need to be conformed AND to find someone willing to sign it off as such. This is somewhat similar to the TCCA owner-maintained aircraft which no longer conform to its TC and can't leave Canada.
 
Reeks of CYA -- did someone skoosh a sonex and it was blamed on cockpit ergonomics and this sort of split-handed operation?

That's a good question and a great possibility. I'm unaware of any accident, incident, or situation that has developed from this as to cause them to issue this "required" Service Bulletin for an experimental aircraft.

Not to beat up the company but they have sent out some other "guidance" that seems to be either for company protection or company profit. Don't misunderstand, I think they are an excellent company with great products but there are things they do that are worthy of one of these -> :dunno:
 
I didn't state that correctly. My bad. What I meant to say was that on other forums there was a discussion about whether it was a legal requirement or not (I edited the OP to clarify). I don't believe that it is but there are some that insist it may be. One argument comes from those who have placed a certified (or previously certified) engine on their experimental aircraft.

The bigger debate is from those who say that while 14 CFR Part 43.1(b)(1) states that Part 43 doesn't apply to experimentals, what does apply is 14 CFR Part 91.417 (a) (2) (V) i.e. the AD or safety directives cited. As I said, I'm not convinced but others are. I comply because it's wise to follow the guidance of the engineers and designers.

Clear as mud ... :)
The FAA has an AC the details that ADs absolutely apply to E/AB if written to unclude them by name or if a part it indicated by SN, not by TC AC. So if you have an O-325 sn xxxx that falls within an AD and that AD specifically states something like 'all sn between ' then you must comply.

Granted its on the honor system, as even an A&P will jave a hard time researching ADs for E/AB inless they subscribe to a service that indexes the ADs and makes them searchable. The FAA web site is complete garbage in this respect.

Maybe the EAA can take 10 minutes out of OSH planning and push the FAA to update the AD index so builders can find critical data like this.
 
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