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.
