SkyDog58
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Canis Non Grata
Refer to 14 CFR 1.3 Rules of Construction.
True/False: Owners Can Fabricate Their Own Modified Parts
- Thread starter Juliet Hotel
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Refer to 14 CFR 1.3 Rules of Construction.
wilkersk
Pattern Altitude
This article is about a well known incident.
https://www.aviationpros.com/home/article/10387511/owner-produced-parts-how-they-affect-maintenance
https://www.aviationpros.com/home/article/10387511/owner-produced-parts-how-they-affect-maintenance
Lachlan
En-Route
Too much. Are you sure you don't want to add "I've forgotten more in my life than you'll ever learn in your life" to the equation as most elders do when in this predicament?
One of my mentors in aviation once told me if a person throws out in a debate they've been doing something for years without any FAA issues usually means the Feds haven't caught up with them yet.
I guess ignorance is bliss on ocassion. Remember as stated multiple times above no external approval required for owner parts. But as side note if you care to learn, reverse engineering is alive and well in the parts production world. It's technically called Identicality and about a third of PMA parts are produced and (gasp) approved in this manner. And thats a fact.
The more the merrier. But I think Doc was there to help you dig the hole you started in the TT post and are continuing here. Don't want to see you throw out your back or something.
I believe knowledge is king. So when a person asks a question looking for that knowledge I prefer to give them the facts first and let them form their opinion. Rarily do you provide any facts, only opinion. Unfortunately, I've seen people who take your type of opinion as fact and get themselves in a bind. It was the reason I came to this site over your opinion on who can touch up paint on a prop. Despite multiple factual examples contrary to your opinion you prefer to remain in the dark. And that is fine by me. There's actually a term for your type of thinking--it's called "post-truth." Look it up sometime.
But whether you want to believe it or not, things have changed since I was born and continue to change. So in the meantime I'll keep my eye open for sales on shovels just in case you wear out your current shovel.
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That's the only way I do it also.
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dtuuri
Final Approach
Really good question. With open mind, I read the applicability section and definitions for Pt 21 and came to the conclusion "product" is an aircraft, engine or prop, "Article" is a part. Since the whole Pt. 21 regulation pertains to approvals for these things it would seem to me the quote you cite is for the manufacturer who owns and modifies test beds. In that context, the pertinent part of the rule makes sense to me:
If a person knows, or should know, that a replacement or modification article is reasonably likely to be installed on a type-certificated product, the person may not produce that article unless it is—Produced by an owner or operator for maintaining or altering that owner or operator's product;
In other words, without a production approval for an aircraft, engine or prop you can't fabricate parts that might wind up on a properly certified one. IMO, of course. The junior lawyers at the Chief Counsel's Office might conclude something else.
FYI: they already have in 1991 or 1993. There is also a FAA memorandum on this. The reason for the "his own product" was to limit the owner/operator to only those aircraft/products they own or have operational control over. Otherwise one would need a PC or other type approval method like PMA. Most Part 135/121 operators use this same 21.9(5) to produce articles for their entire fleets. Another example, some Part 91 type clubs share data for an OPP with their members, however, each member must comply with part production/marking for their specific aircraft. The club can not produce a bunch and then hand them out. But there are ways for one entity to produce the part for each individual member.
dtuuri
Final Approach
I'm quite aware of the interps and the fact that from the airlines down there exists a cottage industry that relies on them. Nevertheless, I've never heard the owner of an airplane refer to it as his/her "product". Don't you find it strange the FAA would? Unless the owner was the builder, that is, and the FAA is referring to it thusly. Anyway, it's my opinion that's how the rule was intended to be interpreted, which it obviously hasn't, so everybody go carry on. I really don't care as long as you're required to disclose all "owner built" parts when you sell.
Checkout_my_Six
Touchdown! Greaser!
well....they should be appropriately documented....with a log book entry. There should be no question what parts are "owner produced". Remember they also will need to be returned to service by an FAA approved person.....like an A&P.
Not really, but I've been involved with the FARs for a number of years. "Aircraft," "engine," and "propeller" are used/defined in 49 USC. It is my understanding, for brevity, certification standards/regulations were written using all-inclusive terms (products/articles) to cover all bases. It's strictly an administrative determination. The performance/operating regulations use the original terms of aircraft, prop, etc. that a pilot or mechanic would use on a daily basis.
Per guidance those parts need to be documented prior to installation. I won't install an OPP unless there is a separate write up signed by the owner detailing the part production and identification. There is also a requirement to physically mark the part.
Aside from the owner write up there is no difference in documenting owner produced parts versus PMA or OEM parts. Yet look how many of those "certified" parts never seem to make it into the aircraft logbooks either, for various reasons. So it's less the part type that matters and more in how the owner conducts his affairs in general when buying an aircraft.
Doc Holliday
En-Route
No one here said or implied it could be.
LOL!
Doc Holliday
En-Route
and car3 certified aircraft have it much easier regarding replacement parts. however instillation except for part 43 routine maintenance items must be loged in by a a & p unless the part never broke.
The original question that started the thread was whether an owner could manufacture a blue lens instead of a factory red one.
My understanding of the regs is that if you can find documentation that the lens is made from 'Plexiglass MC' and the color is 'xyz aviation red', then you as an owner can buy a sheet of 'Plexiglass MC' in 'xyz aviation red' and have someone cut a lens that conforms in dimensions to the original. Properly documented, an A&P can install that lens in the owners plane and sign off on it.
Now, considering that the color of the lens is integral to what it does, it would seem that you can't just make the lens in any color you want. However, if you can find a drawing for that part giving the color as unicorn rainbow, you would be a-ok to produce one in that color.
StevieTimes
Line Up and Wait
https://www.faa.gov/about/office_or...17/Friedman - (2017) Legal Interpretation.pdf
FAA response: No. Section 21. 9( a) lists six ways a person may produce replacement or modification articles, including production under a type certificate or an FAA production approval. However, no one method is given precedence over another, so parts properly fabricated during maintenance to be subsumed into the higher level article or product upon which maintenance is being performed, meet the FAA's maintenance regulations. The fact that a type certificate holder may have parts available has no bearing on the permissible use of parts fabricated in accordance with §21.9(a)(6).
FAA response: No. Section 21. 9( a) lists six ways a person may produce replacement or modification articles, including production under a type certificate or an FAA production approval. However, no one method is given precedence over another, so parts properly fabricated during maintenance to be subsumed into the higher level article or product upon which maintenance is being performed, meet the FAA's maintenance regulations. The fact that a type certificate holder may have parts available has no bearing on the permissible use of parts fabricated in accordance with §21.9(a)(6).
If the original material documents are unavailable, another option exists in AC 23-27 that allows a materials substitution method provided the aircraft was TC'd prior to 1980.
Curious. Why do you think CAR 3 aircraft replacement parts are different or easier?
?? Owner parts are produced under 21.9(a)(5). There are different requirements for maintenance part fabrication (the LOI subject) which falls under different FAA guidance like AC 43-18.
Tom-D
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Tom-D
Better read (b) of that regulation..
(b) Except as provided in paragraphs (a)(1) through (a)(2) of this section, a person who produces a replacement or modification article for sale may not represent that part as suitable for installation on a type-certificated product.
So who's going to make this part?
Am I going to make the part ? am I selling it to who needs it?
Lots of pit falls in doing this.
(b) Except as provided in paragraphs (a)(1) through (a)(2) of this section, a person who produces a replacement or modification article for sale may not represent that part as suitable for installation on a type-certificated product.
So who's going to make this part?
Am I going to make the part ? am I selling it to who needs it?
Lots of pit falls in doing this.
MauleSkinner
Touchdown! Greaser!
Is there any part of the preceding discussion to which your comment actually applies?
StevieTimes
Line Up and Wait
Aren't we talking about owner produced parts? I thought we were indeed talking about 21.9(a), which includes 5. I'll bold the part I was trying to point out:
FAA response: No. Section 21. 9( a) lists six ways a person may produce replacement or modification articles, including production under a type certificate or an FAA production approval. However, no one method is given precedence over another, so parts properly fabricated during maintenance to be subsumed into the higher level article or product upon which maintenance is being performed, meet the FAA's maintenance regulations.
weirdjim
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Tom-D
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Tom-D
Well,, who's making the part, is a good question.
How many owners actually have the tools and know how to make any aircraft part in accordance approved methods.
This thread has like many others has left reality.
dtuuri
Final Approach
So, what's the difference? When does a fabricated item cross over from an "acceptable repair" to an "owner produced part"? My take from above is when it's for the owner's production test bed, but when else under the common interpretation?
Tom-D
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Tom-D
Actually when no portion of the old part can be used.
Example: when you can save the data plate from a muffler you can built a new one weld the old data plate on it and call it a repair.
A different example, a skin is made for a wing repair, when used it will simply be signed off as a repair of there wing.
dtuuri
Final Approach
Sure, I see that. But AC 43-13-? (way back when I was a mechanic, don't know about now) spends time explaining how to verify materials, so I think that would imply making whole parts from stock.
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There is a list of ways how the owner can participate in the production of the part. There is no requirement for the owner to do all of the steps, he can provide materials and instructions and it is a-ok.
MauleSkinner
Touchdown! Greaser!
21.9(b) is about making parts for sale, not owner-produced for one’s own airplane. Nothing in this has been thread about making parts for sale.
Considering the LOI is a legal document and addresses 21.9(a)(6) specifically per the subject line, if you prefer to highlight a single line and apply it out of context to a different regulation that is your choice. However, that LOI as zero to do with owner pro parts.
Probably very few. But the owner is not required to personally produce the part. There is a requirement the owner must participate in 1 of 5 ways. There are a number of FAA docs that detail those 5 items along with a number of articles explaining the process.
Unfortunately, the only reality it's left is yours. But that's your choice.
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Never. Repairs are handled under Part 43. Owner parts are produced under Part 21 and they can only be new parts. Separate rules entirely. However, you can use an owner part in a larger Part 43 repair like owner produced fittings for a wing repair.
Don't follow your reference to the "owner's production test bed." Are you are implying the manufacturer is the "owner?" The Feds define an owner/operator as the person who has legal control of an aircraft. This is different than a manufacturer who have their own authorizations.
Cap'n Jack
Final Approach
No, the thread is still on base.
It really depends on the part and materials. As @weirdjim mentioned earlier, I can buy one of his kits, build it, and place it in a type-certificated plane; I feel reasonably competent wielding a soldering iron. I could make something simple like an inspection cover from sheet metal. I could do some fiberglass work, although I don't like messing with that stuff. A simple plastic bezel that is non-structural? I can 3-D print it.
There's a lot of skilled people. If I can't do it, I can find someone who knows how to do it, and has the tools to do so.
dtuuri
Final Approach
Then you agree with Tom, they must be made from new stock. To which I replied:
Are you saying AC 43.13-whatever doesn't allow fabricating replacement parts wholly from new stock?
I was referring to my post earlier to which you made a reply:
Part 21 seems to be all about product (aircraft, engines and props) "approvals" and approvals for parts that might wind up on those devices. Part 43 deals with repairs, including fabrication of replacement components, of those devices. I'm not sure it's necessary to refer to Part 21 for authority to fabricate items as "owner provided parts" at all unless I'm missing some limitation spelled out in the latest iteration of AC 43.31-?? (CAM 18, once upon a time).
So, if you can help me with that I'd appreciate it. We seem to agree that Part 21 and 43 are completely different, I just don't see the need to invoke 21 when repairing a type-certificated product i/a/w 43.
Yes.
No. But as we agree Part 21 and Part 43 are different so are the terms being used. A mechanic can only fabric a part for consumption in a Part 43 repair or alteration. A mechanic can not produce, i.e., manufacture, a part. An owner can produce a part. Might seem trivial but its not.
Because Part 21 is only a part sourcing outlet, not a repair approval outlet. Approval for all aviation parts only comes from Part 21. Even the authorization for a mechanic to fabric a part comes from Part 21 and not Part 43. And technically in order for the mechanic to use that 21 authorization they are required to have a quality system in place. The quality system has never really been enforced down to the mechanic level, however, it has slowly moved up the food chain in certain circles, so much so the Feds issued AC 43-18 to offer guidance to that issue. The Part 21 owner part has no quality system requirement.
Perhaps a very simple/general, perfect world example:
Owner A damaged the wing tip of his 172. He has a mechanic inspect the area under Part 43 and devise a repair scheme which would require replacement of the wing tip assembly and attachment angle, P/N: OEM 123456. A new PMA wing tip is purchased, but the tip attachment angle has a 2 year lead time from the OEM. So that leaves 2 options for the angle: the mechanic can fabric a new angle under 21 via 43 or the owner can produce a new angle under 21.
By rule, if the angle is fabricated, it requires the mechanics quality system to verify the final part, and his write up would state as such: Removed angle OEM 123456 and fabricated angle from 2024-T3....
Also by rule, if the owner elects to produce the angle, using the mechanic and same process used to fabricate the angle, the owner enters a write up on the angle production and identifies it as P/N: Owner A 123456. The mechanic in turn writes up: Replaced angle OEM 123456 with angle Owner A 123456........
The owners angle is no different than the OEM angle from the Part 43 repair side. They're both Part 21 replacement parts.
There's a few holes in the example, but hopefully you follow the path.
dtuuri
Final Approach
Oh, I follow it all right, I just don't think it passes the sniff test. To start with, in order to support your (and everybody else's) interpretation you have to believe the FAA made typos in the rule. I don't. Then you have to think the FAA makes owners use certified mechanics to inspect and repair their aircraft because owners aren't properly qualified, yet at the same time believe "owners" ARE qualified to make parts. Sorry, I don't see it. But It really doesn't bother me too much because in the end, either way, the part is ultimately approved by somebody who ought to be qualified. My way, though, the owner is out of the picture. And you won't need no stinking SMS.
Curious. What specific typos are you referring to?