True/False: Owners Can Fabricate Their Own Modified Parts

Curious. What specific typos are you referring to?
Summarizing, the FAA meant to say "aircraft" and some junior lawyer changed it to "product" in the final approval process.
You follow this line of thinking here when you equate "aircraft" with "product" by use of a slash between the two words:
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.

My comments about this one follow:

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.
The applicability section of Part 21 specifically distinguishes between "products" and "articles", such as parts. "Products" are devices that need certifications and are only aircraft, engines and propellers—nothing else. That's not the same as you describe: "all-inclusive terms". Instead, it's an exclusive term that excludes the parts the aircraft, etc., are made from. End-users don't have products, OEMs do. End-users don't need knowledge of Part 21, that's for OEMs who seek approvals. Anybody making parts for sale aren't making "products", they're making "articles" under Part 21 and need approval unless they limit the distribution of the part to their own aircraft, engine or propeller (product). This makes practical sense to me for development reasons.

That's my interpretation and I only offer it for conversation's sake. I see no reason aircraft can't be completely maintained under Part 43 and AC 43.13? (what IS the current AC??). If somebody wants to mass produce parts for sale, then Part 21 is the place to go.
 
let me try a different tack:
I see no reason aircraft can't be completely maintained under Part 43
They are and Part 43 is the only FAR that provides the means (except inspections which is Part 91). I'm in full agreement. But in order to maintain that aircraft, what are your legal options to procure replacement and modification parts?
what IS the current AC??
AC 43.13-1B and 43.13-2B
specifically distinguishes between "products" and "articles", such as parts.
A product= aircraft, engines, propellers.
An article=everything used to to build/maintain/alter a product.
All products and articles require certification. Part 21 is the only FAR that provides a means to that certification. Part 43 does not.
End-users don't have products,
End-users own, operate, and maintain products.
Anybody making parts for sale// aren't making "products",
Correct. Two parts to your quote: If talking specifically on replacement or modification articles (parts) that is covered in 21.9. To make products for sale that falls under 21 Subpart G and requires a Production certificate.
they're making "articles" under Part 21 and need approval unless they limit the distribution of the part to their own aircraft, engine or propeller (product)
Which is the definition of an owner produced part. But that part must still conform to approved data.
 
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let me try a different tack:

They are and Part 43 is the only FAR that provides the means (except inspections which is Part 91). I'm in full agreement. But in order to maintain that aircraft, what are your legal options to procure replacement and modification parts?

AC 43.13-1B and 43.13-2B

A product= aircraft, engines, propellers.
An article=everything used to to build/maintain/alter a product.
All products and articles require certification. Part 21 is the only FAR that provides a means to that certification. Part 43 does not.

End-users own, operate, and maintain products.

Correct. Two parts to your quote: If talking specifically on replacement or modification articles (parts) that is covered in 21.9. To make products for sale that falls under 21 Subpart G and requires a Production certificate.

Which is the definition of an owner produced part. But that part must still conform to approved data.
I don't think we need to spend more time on this. The FAA rendered an interpretation differently than I would have and I'm used to it. I'll just leave with this quote from from my ancient AC 43.13-1 which to me authorizes fabricating parts from new stock without need of additional Part 21 authorization:

"62. Selection of Aluminum for Replacement Parts. <snipped>"​

Not "repaired parts" but "replacement parts". Made from new stock, else why instructions on how to select the material.
 
I don't think we need to spend more time on this.
I agree. But to close, the legal/regulatory authorization to fabricate parts per AC 43-13 is derived from Part 21.9(a)(6). Enjoyed the discussion.;)
 
Not an A&P, or a lawyer - but I did see an article in AOPA in the not too distant past: you (the owner) can build any part you need (or have it built based on your specs). Some verbiage about "substantially identical. . .etc". As I recall, the intent was pretty clear, no ambiguity - restricted to your use, your airplane - no cottage industry building and selling Cessna battery boxes, for example.
 
Not an A&P, or a lawyer - but I did see an article in AOPA in the not too distant past: you (the owner) can build any part you need (or have it built based on your specs). Some verbiage about "substantially identical. . .etc". As I recall, the intent was pretty clear, no ambiguity - restricted to your use, your airplane - no cottage industry building and selling Cessna battery boxes, for example.
Setting aside the perceived legality, do you think it's a wise idea to let any old owner build parts for their certified aircraft?
 
Setting aside the perceived legality, do you think it's a wise idea to let any old owner build parts for their certified aircraft?

The regulations don't question how wise the owner is. It's already black and white as per the regulation.

But, as an aside, we already have owners replacing parts and doing maintenance without the proper certification (A&P). We also have owners who already fabricate parts and install them "under the radar". And we have owners who seek out the "$200 annual" which involves an IA who is selling his signature.
 
So, let me see if I follow. It isn't wise to let any old owner change the part, but it is wise to let them build it?

Not everything in the regulations is perfectly logical. The way for me to resolve that apparent conflict would be to allow the owner to change the part as well.
 
Not everything in the regulations is perfectly logical. The way for me to resolve that apparent conflict would be to allow the owner to change the part as well.
How about the owner in question being otherwise subject to FAA oversight approval, like an OEM or air carrier? Tracing parts back to an approved manufacturing process may in fact already be a requirement for OPP (IDK). That would be a big burden on an owner who never met the FAA before. Better, IMO, to let an A&P fab it up under Pt 43 & AC 43.13-1.
 
How about the owner in question being otherwise subject to FAA oversight approval, like an OEM or air carrier? Tracing parts back to an approved manufacturing process may in fact already be a requirement for OPP (IDK). That would be a big burden on an owner who never met the FAA before. Better, IMO, to let an A&P fab it up under Pt 43 & AC 43.13-1.
If his A&P isn’t providing the necessary oversight, it’s probably not going to be done properly by the A&P under Part 43 anyway.
 
Setting aside the perceived legality, do you think it's a wise idea to let any old owner build parts for their certified aircraft?
Honestly, yeah. . .our aircraft aren't the space shuttle - a battery box isn't a variable width inlet duct for a Mach 2 fighter. If I remember the article correctly, the rules called for a substantially identical part - dimensions, material, design. Part of the logic is to keep orphan aircraft airworthy when OEM isn't available. Or when OEM is cost prohibitive.

Still two hands on it, two sets of eyes; the owner and the A&P. And perhaps the fabricatior, if the owner had the oart made by a third party
 
This thread brings to mind 'Replacement in Kind" i.e, form, fit, function in the CM world. Think I will stop thinking.... it hurts

I digress
 
It isn't wise to let any old owner change the part, but it is wise to let them build it?
Is your premise along safety/quality lines that the owner part would be substandard, or is it that the FARs are poorly written by allowing an owner to produce a certified part but he's not allowed to install that part on his certified aircraft?
 
Is your premise along safety/quality lines that the owner part would be substandard, or is it that the FARs are poorly written by allowing an owner to produce a certified part but he's not allowed to install that part on his certified aircraft?
There are owners who can’t be trusted to make sure it’s done right, therefore NO owner should be allowed to do it.

Much like there are pilots who can’t be trusted to do things right, therefore no one should be allowed to fly.
 
Is your premise along safety/quality lines that the owner part would be substandard, or is it that the FARs are poorly written by allowing an owner to produce a certified part but he's not allowed to install that part on his certified aircraft?
Well you kind of have to admit it seems silly that a person who without any certification is expected to know how to identify and match metal types and fabrication techniques necessary to replicate a certified part, is also expected to have no idea how to identify and use the aviation grade fasteners, torque values and safety wire required to install that part.

Everyone knows how to identify and source proper grade certified aluminum, use a metal brake, deburr edges and set rivets, but unless they've been to school and obtained an A&P cert, nuts, bolts and wrenches somehow bewilder them. :rolleyes:
 
Is your premise along safety/quality lines that the owner part would be substandard, or is it that the FARs are poorly written by allowing an owner to produce a certified part but he's not allowed to install that part on his certified aircraft?
I was trying to set aside the regulation as interpreted and start with a clean sheet. We, not including @weilke, accept the wisdom that owners aren't knowledgeable enough to maintain their aircraft themselves, certain itemized exceptions aside. Ownership requires only money not skill. When building aircraft or pieces of it for distribution we want only FAA certified processes involved. Same goes for the privilege of just operating the things.

So, where is the logic that non-skilled, un-certified owners should make their own parts?

A part made under the watchful eye of an A&P isn't the same as an "owner produced part", in my view. It's really by an A&P. Airlines, OEMs, repair stations and A&Ps all make parts under FAA oversight of one kind or another. Some own their own aircraft. For them, though, part-making is done under existing oversight. Extrapolating the meaning of "owner" from that kind to, say, a Tripacer owner is questionable to me. I don't see the wisdom in it.
 
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I was trying to set aside the regulation as interpreted and start with a clean sheet. We, not including weilke, accept the wisdom that owners aren't knowledgeable enough to maintain their aircraft themselves, certain itemized exceptions aside. Ownership requires only money not skill. When building aircraft or pieces of it for distribution we want only FAA certified processes involved. Same goes for the privilege of just operating the things.

So, where is the logic that non-skilled, un-certified owners should make their own parts?

A part made under the watchful eye of an A&P isn't the same as an "owner produced part", in my view. It's really by an A&P. Airlines, OEMs, repair stations and A&Ps all make parts under FAA oversight of one kind or another. Some own their own aircraft. For them, though, part-making is done under existing oversight. Extrapolating the meaning of "owner" from that kind to, say, a Tripacer owner is questionable to me. I don't see the wisdom in it.
So how does an A&P make a replacement curved glass windshield for an antique airplane under Part 43?
 
“The Minneapolis FSDO doesn’t do field approvals.”

Apparently the oversight isn’t in place to allow mechanics to do it, either.
Well, you know how our federal government is strapped for resources. Employees are probably all out collecting student loans.
 
So, where is the logic that non-skilled, un-certified owners should make their own parts?

A part made under the watchful eye of an A&P isn't the same as an "owner produced part", in my view.
My A&P is very experienced and capable, but I've made several parts for my planes that I'm more capable of designing and fabricating than he is. I'm an engineer with almost 30 years of machine design experience and I own a machine shop. I know how to design, I know how to pick materials, and I know how to fabricate parts. I'm also the one who'll be flying the aircraft, along with my family. When I make a part I discuss it with my A&P in advance in case there's something I'm overlooking. I also show him the drawings and explain my choices in materials and then I install it "under his watchful eye".

We allow people to weld up their own trailer hitches to tow their car behind their motor home. That's a heck of a lot more dangerous than an airplane owner fabricating a little bracket.
 
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I was trying to set aside the regulation as interpreted and start with a clean sheet. We, not including @weilke, accept the wisdom that owners aren't knowledgeable enough to maintain their aircraft themselves, certain itemized exceptions aside. Ownership requires only money not skill. When building aircraft or pieces of it for distribution we want only FAA certified processes involved. Same goes for the privilege of just operating the things.

So, where is the logic that non-skilled, un-certified owners should make their own parts?

A part made under the watchful eye of an A&P isn't the same as an "owner produced part", in my view. It's really by an A&P. Airlines, OEMs, repair stations and A&Ps all make parts under FAA oversight of one kind or another. Some own their own aircraft. For them, though, part-making is done under existing oversight. Extrapolating the meaning of "owner" from that kind to, say, a Tripacer owner is questionable to me. I don't see the wisdom in it.

From the linked presentation above:

How is it that the rule allows an aircraft owner or operator to produce parts for his aircraft, but not an A&P? (Simple)The responsibility follows the money!
 
My A&P is very experienced and capable, but I've made several parts for my planes that I'm more capable of designing and fabricating than he is. I'm an engineer with almost 30 years of machine design experience and I own a machine shop. I know how to design, I know how to pick materials, and I know how to fabricate parts. I'm also the one who'll be flying the aircraft, along with my family. When I make a part I discuss it with my A&P in advance in case there's something I'm overlooking. I also show him the drawings and explain my choices in materials and then I install it "under his watchful eye".

We allow people to weld up their own trailer hitches to tow their car behind their motor home. That's a heck of a lot more dangerous than an airplane owner fabricating a little bracket.
I would think it was "owners" with your level of expertise involved in the aviation industry the FAA had in mind when drafting Part 21, not manufacturers of trailer hitches or other non-aviation enterprises. Certainly not your run-of-the-mill Cessna owner with material supplies from Auto Zone, K-mart and Lowe's and tools from Harbor Freight.
 
From the linked presentation above:

How is it that the rule allows an aircraft owner or operator to produce parts for his aircraft, but not an A&P? (Simple)The responsibility follows the money!
I saw that too. That's where I decided the author didn't have much sense.
 
I would think it was "owners" with your level of expertise involved in the aviation industry the FAA had in mind when drafting Part 21, not manufacturers of trailer hitches or other non-aviation enterprises. Certainly not your run-of-the-mill Cessna owner with material supplies from Auto Zone, K-mart and Lowe's and tools from Harbor Freight.

That’s pure speculation on your part. And the regulation doesn’t support this.
 
a person who without any certification is expected to know how to identify and match metal types and fabrication techniques necessary to replicate a certified part,
where is the logic that non-skilled, un-certified owners should make their own parts?
Certainly not your run-of-the-mill Cessna owner with material supplies from Auto Zone, K-mart and Lowe's and tools from Harbor Freight
The 2 facts people tend to forget in this discussion is the owner doesn't have to have the knowledge, tools, materials or even physically build the part. He is only required to participate in 1 of 5 methods as he simply has the regulatory authority to have it produced. Nothing more.

The other fact that escapes most posts above is the end result part must conform to FAA approved data. The infamous nose strut pictured did not conform to data and was an illegal part. And the mechanic got hammered for installing a unairworthy part. So as for "oversight" I think requiring approved data and a secondary "approval"/signature to be more than sufficient.

But what I always enjoy with discussions on this topic is the double standard other owners portray to part producing owners in general. It's been alluded to above. So if you believe an owner is not capable of having a part made on his behalf per the FARs (approved data/Part 43 oversight), then why should any owner be allowed to operate an aircraft on their own behalf without say... at least the same requirements as owner produced parts?

Perhaps if an owner had to make an logbook entry prior to each flight stating the aircraft conforms to its FAA approved data and then subsequently have their mechanic sign off that the aircraft meets the requirements of the Part 43, I wonder how much that would improve GA safety? Oh, that's right, I forgot, it's only the owner produced parts that matter.;)
 
That’s pure speculation on your part. And the regulation doesn’t support this.
Yes, it's speculation. My speculation is this memo everybody cites wasn't written with Ercoupes in mind but rather the airlines: http://www.velocolutions.com/FAA-owner-manufactured-part.pdf

Let me cherry pick one sentence near the end of Attachment A that summarizes what my instincts tell me.

"Compliance with Part 43 gives the assurances of the quality control for a part produced by a Part 65 mechanic."
That's all I believe should be needed. I don't think we need our GA owners thinking they can do what the airlines and OEMs do in order to save money just because the FARs reference "owner produced parts". That reference, I speculate, probably wasn't meant for us since it isn't needed anyway.
 
Bell206 has explained it in detail, many times over now.

And he’s done it well.
 
Actually, the way I heard it is that the section was written at the behest of the aerial applications organization back prior to WWII to let the cropduster that banged up a wingtip to fabricate a a rib and get back to dusting.

Jim
 
Actually, the way I heard it is that the section was written at the behest of the aerial applications organization back prior to WWII to let the cropduster that banged up a wingtip to fabricate a a rib and get back to dusting.

Jim

Doesn’t matter what myth anyone chooses to believe. Fact is it’s in the regulations, and clear on its intent.
 
Actually, the way I heard it is that the section was written at the behest of the aerial applications organization back prior to WWII to let the cropduster that banged up a wingtip to fabricate a a rib and get back to dusting.

Jim
That's a myth.
 
Doesn’t matter what myth anyone chooses to believe. Fact is it’s in the regulations, and clear on its intent.
I've been away while I chased back through decades of regulations looking for the genesis of "owner produced parts". The origin is not clear and the meaning, imo, isn't what you guys apparently think.

First, let me eat a big slice of humble pie before I report my findings: My idea that an owner's "product" must apply to an OEM's test bed is debunked. I was not correct. Gulp. Enough of that.

I searched through regs all the way back through the 60's, 50's and 40's clear back to 1937. Then, it was the CAA not FAA and CAR 18 preceded FAR 43. I saw no mention of "owner parts" until the changeover to FARs circa 1965. Part 21.303 is where owner parts were first noted as an exception to requirements for production approvals. Later, the "owner part" section was moved to a newly written paragraph 21.9 as part of an NPRM. I also read the pertinent parts of the preamble for the final rule concerning the discussion of owner parts.

Here's the typical language that existed in the 1950s as to who can perform maintenance. I could find no references in other sections, like CAR 2 or 3, for owner parts. Note the references to OEMs and airlines in addition to the familiar authorized persons:

§ 18.10 Persons authorized to perform maintenance, preventive maintenance, repairs, and alterations. No person shall perform maintenance, preventive maintenance, repairs, or alterations on civil aircraft of United States registry except as provided as follows:

A certificated mechanic or a person who works under the direct supervision of such mechanic may perform maintenance, repairs, and alterations on aircraft or aircraft components including related appliances, appropriate to his rating, but excluding major repairs and alterations to propellers and all repairs and alterations to instruments.

An appropriately rated repair station may perform maintenance, repairs, and alterations on aircraft or aircraft components, including propellers and appliances, as provided in Part 52 of this subchapter.

A certificated pilot may perform, on aircraft owned or operated by him, except aircraft used in air carrier service, such preventive maintenance as may be authorized by the Administrator.

A manufacturer shall be subject to the requirements of paragraphs (a) and (b) of this section, except that he may rebuild or alter:

Any product manufactured by him under a type or production certificate, or

Any product manufactured by him and approved under the terms of a Technical Standard Order or Product and Process Specification issued by the Administrator.

An appropriately certificated air carrier may perform maintenance, repairs, and alterations on aircraft or aircraft components, including propellers and appliances, as provided for in its continuous airworthiness maintenance and inspection program and its maintenance manual.

§ 18.11

Persons authorized to approve maintenance, repair, and alterations—

Maintenance, minor repairs, and minor alterations. No airframe, powerplant, propeller, or appliance which has undergone maintenance, minor repair, or minor alteration may be approved and returned to service except by one of the following:

An appropriately rated certificated mechanic, or

An appropriately rated certificated repair station, or

An appropriately certificated air carrier, or

A manufacturer, if the product has been rebuilt or altered by the manufacturer under the provisions of § 18.10 (d).

<snip>
When Part 21 came into being it mentioned, for the first time that I could find, "owner parts":

Sec. 21.303

Replacement or modification parts.

(a) Except as provided in paragraph (b) of this section, no person may produce replacement or modification parts for sale for installation on a type certificated product unless he has complied with Secs. 21.21(b)(1), 21.33, 21.43, Subpart D (if applicable) and Sec. 45.15 of this chapter.
(b) This section does not apply to the following:
(1) Parts produced under a type or production certificate.
(2) Parts produced by an owner or operator for maintaining or altering his own product.
(3) Standard parts (such as bolts and nuts) conforming to established industry or United States specifications (e.g. SAE and military specifications and FAA Technical Standard Orders).
When this section was relocated and the reach of the language was extended to include even those producers who made parts that "might" wind up on type certified products despite not being specifically made for them, the preamble said this regarding parts made during a repair:

...the SBA's Office of Advocacy asked the FAA to clarify and confirm that the existing ability of a repair shop to produce a part during maintenance activities remains in place.
...
It is not our intent to preclude that activity. To address that concern and clarify our intent, we established an exception in Sec. 21.9(a)(6).
...
Maintenance providers who do not have a quality system may continue to fabricate owner-produced articles for installation on type-certificated aircraft using the guidelines set forth in Policy Memorandum, Definition of "Owner Produced Part,'' Section 21.303(b)(2), August 5, 1993.
So, the authority for a mechanic fabricating a part, according to that memorandum's appendix, is Part 43, not 21.9. The part that mechanic makes is dubbed an "owner produced part". That doesn't mean an owner has a right to make a part for his or her airplane any more than the man in the moon. If the owner's mechanic or another mechanic can't be found who will install it, the owner is dead in the water. Not much of a "right" if that's what anybody is thinking. I would have as much "right" having a part installed I made for the owner as he or she does, although it wouldn't likely happen. :)
 
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