Airspeed indicator

Here is the memo from the FAA General Counsel. I leave the interpretation to you:

Memorandum
U.S. Department of Transportation
Federal Aviation Administration
Subject: INFORMATION: Definition of \"Owner
Produced Part,\" FAR 21.303(b) (2)
Date:
AUG
5 1993
From: Assistant Chief Counsel for Regulations,
AGC-200
Reply to Attn. of:
To: Manager, General Aviation and Commercial
Branch, AFS-340
This responds to your memorandum, dated April 8 to Senior Attorney Mardi Thompson, in which you asked for a definition of
\"owner (or operator] produced part,\" as described in Federal Aviation Regulations (FAR) Section 21.303(b) (2). You asked several questions in your memorandum. We answer your questions in the order you asked them. Attachment A provides a background foundation for our answers. The answers should frame a workable definition of how to determine if the exception in FAR 21.303 (b) (2) applies.
We answer your questions as follows:
First question: Does the owner have to manufacture the part himself, in order for the part to be considered an “owner produced\" part? Answer: No. An owner would be considered a producer of a part if the owner participated in controlling the design, manufacture, or quality of the part. We would look at many factors in determining whether a person participated in controlling the design, manufacture, or quality of a part. The following would tend to indicate the a person produced a part:
1. The owner provided the manufacturer with design or performance data from which to manufacture the part. (This may occur, for instance, where a person provided a part to the manufacturer and asked that the part be duplicated.)
2. The owner provided the manufacturer with materials from which to manufacture the part.
3. The owner provided the manufacturer with fabrication processes or assembly methods to be used in the manufacture
of the part. .
4. The owner provided the manufacturer with quality control procedures to be used in the manufacture of the part.
5. The owner supervised the manufacturer of the part.


We would not construe the ordering of a part, standing alone, as participating in controlling the design, manufacture, or quality of a part.
Second question: Can the owner contract for the manufacture of the part, and still have a part that is considered an \"owner produced\" part? Answer: Yes, in certain circumstances. The owner would still be considered a producer of the part if he participated in controlling the design, manufacture, or quality control of the part. Note that, as explained in Attachment A, the person with whom the owner contracted would also be a \"producer. II
Third question: Can the owner (merely) supervise or assume responsibility for a mechanic manufacturing the part for the owner, and still have a part that is considered an \"owner produced\" part? Answer: Yes, with respect to supervision. Owner supervision would indicate that the owner participated in controlling the design, manufacture, or quality of the part. A common example would be where an air carrier mechanic manufactured a part for installation on the air carrier's aircraft; the part produced would be owner or operator produced. We are not sure what you meant by the owner \"assuming responsibility\" for manufacture of a part. If your reference was to something other than participating in controlling the design, manufacture, or quality control of the part, our opinion is that the owner probably would not be determined to have produced the part.

Fourth question: Can an owner contract with a non-certificated individual to manufacture a part for use on the owner's aircraft, and still have a part that 1S considered an \"owner produced\" part? Answer: Yes, in certain circumstances. If the owner participated in controlling the design, manufacture, or quality of the part, the part would be considered to be produced by the owner. However, as explained in Attachment A, the non-certificated person would also be considered a \"producer.\"
Fifth question: If a mechanic manufactured parts (e.g., wing ribs) for an owner, and the parts were associated with a repair the mechanic was performing, would manufacture of the parts be considered maintenance associated with the repair, or production of a part by the owner for maintaining the owner's aircraft? Answer: It could be one or the other; in neither case, however, would there necessarily be an FAR violation. If it was concluded that the owner participated in controlling the design, manufacture, or quality of the part, he would be a producer, and the exception in FAR 21.303(b) (2) would apply. Therefore, the mechanic would not be in violation of 21.303(a)


As noted above, prior to Amendment 21-41, FAR 21.303(a) prohibited each person producing a replacement or modification part for sale for installation on a type certificated product from doing so without holding a PMA. In Amendment 21-41, the FAA amended FAR 2l.303(a) to allow a PMA holder to contract with a subcontractor or supplier to manufacture a modification or replacement part under the holder's PMA In that amendment, the FAA recognized that a modification or replacement part can conform to the approved design data and be safe for installation on a type certificated product, as long as the part is produced under an approved fabrication inspection system (FIS).
Amendment 21-41 did not specifically address who \"should have held the PMA\" where the part was produced in the absence of a
FMA. However, any interpretation of FAR 21.303(a) should be consistent with the focus in that amendment on the establishment and maintenance of the FIS; therefore, we submit that 21.303{a) creates liability for production of a modification or replacement part for sale for installation on a type certificated product for each person who:
1. Participates in controlling the design, manufacture, or quality of the part.
'\"-
2. And does so with the intent that the part be sold for installation on a type certificated product.
We would look at many factors in determining whether a person participated in controlling the design, manufacture, or quality,
_of a part. The following would tend to indicate that a person participated in controlling the design, manufacture, or quality of a part (i.e., \"produced\" the part):
1. The person provided the manufacturer with design or performance data from which to manufacture the part. (This may occur, for instance, where a person provided a part to a manufacturer and asked that the part be duplicated.)
2. The person provided the manufacturer with materials from which to manufacture the part.
3. The person provided the manufacturer with fabrication processes or assembly methods to be used in the manufacture of the part.
4. The person provided the manufacturer with quality control procedures to be used. in the manufacture of the part.
5. The person supervised the manufacturer of the part.
We would not construe the ordering of a part, standing alone, as participating in controlling the design, manufacture, or quality of a part.

(continued next entry)
 
- - --
- ----

One other issue needs to be addressed. Section 21.303(a) prohibits a person from producing a part for sale for installation on a type certificated product when the part is not produced pursuant to a PMA. The general intent of the proscription in FAR 21.303(a) is to prevent the introduction of an unapproved part into the aviation stream of commerce, where it could be subsequently installed on a type certificated product(s). The terms of 21.303(a), including \"for sale,” are defined in that context.
Notwithstanding that repair stations and mechanics bill their customers for parts, along with the labor of installing parts, those entities produce the parts for the purpose of accomplishing maintenance on products, limited to those products brought in by their customers. As described in Order No. 8000.50, a repair station may produce a replacement or modification part, under FAR Parts 43 and 145, for an STC modification or a field-approved repair or alteration, given certain circumstances that assure quality control of the part produced. Compliance with Part 43 gives the assurances of the quality control for a part produced by a Part 65 mechanic. In addition, compliance with the maintenance recordkeeping requirements memorializes the circumstances of production and installation of the part. Accordingly, the objectives of Subpart K are achieved when a part is produced by a repair station or mechanic for installation on a customer's product: the installed part is introduced into the aviation stream of commerce with the necessary evidence of the part's suitability. Thus, one can conclude, as a matter of law, that a repair station or mechanic has not produced the above-described part \"for sale\" for installation on a type certificated product, as defined in the context of 21.303 (a).


Attachment A
Background
Section 21.303(a) of the Federal Aviation Regulations (F&~) states:
Except as provided in paragraph (b) of this section, no person may produce a modification or replacement part for sale for installation on a type certificated product unless it is produced pursuant to a Parts Manufacturer Approval issued under this subpart.
Section 21.303(a) appears to contemplate that more than one person can '''produce'' a modification or replacement part. We base this observation on the following:
1. The regulation proscribes certain behavior unless the part is produced pursuant to a PMA; it does not specifically state that each person who is producing the part must hold a PMA. In fact, prior to Amendment 21-41, FAR 21.303(a) prohibited each person producing a replacement or modification part for sale for installation on a type certificated product from doing so without holding a PMA. In Amendment 21-41, the FAA amended
21.303(a) to allow a PMA holder to contract with a subcontractor or supplier to manufacture a modification or replacement part under the holder's PMA. That amendment recognized that more than one person can participate in the production of a part.
2. The only meaningful interpretation of FAR 21.303(b) accommodates the view that a modification or replacement part can be \"produced\" by more than one person. Section 21.303(b)(2) excepts from the PMA requirement of 21.303(a) “[p] arts produced by an owner or operator for maintaining or altering his own product. II If the 21.303(b)(2) exception were to apply only when the owner or operator produces the part, it would only except from 21.303(a) the production of a part produced by the owner or operator for sale to himself. This result would be illogical. Thus, 21.303(b)(2) must be interpreted as addressing the situation where a part is produced by an owner (or operator) and also is produced by another person.
.



If it was concluded that the mechanic produced the part for the purpose of effectuating the repair, the question would remain whether the mechanic would be in violation of 21.303(a). We submit that the mechanic would not be in violation of 21.303(a), because, as explained in Attachment A, the mechanic did not produce the part for sale for installation on a type certificated product.
We hope the above answers respond to your needs. For further discussion, please telephone Carey Terasaki, AGC-210, at
(202) 267-80
 
The key word you use, replace, determines which type of part (TSO vs non-TSO) you can use. Part replacement as it is implied, and I believe stated in some obscure document, is the removal and installation of a part that conforms to an aircraft's type design. So to remain in conformity you would need an "approved" part to do so, i.e., a TSO or PMA or OEM original part. However, if you choose to alter (key word) your aircraft then the TSO vs non-TSO issue is no longer valid. An aircraft alteration as it is implied is a planned change to an aircraft's type design. And just as it is stated the VAL Avionics article I post on occasion, alterations follow a different set of rules which make installing a non-TSO part legally possible.


With that key thought and this definition, the doors of possibilities certainly open quickly. With that in mind, why would experimental avionics producers not be suggesting this path?


§ 21.93 Classification of changes in type design.
(a) In addition to changes in type design specified in paragraph (b) of this section, changes in type design are classified as minor and major. A “minor change” is one that has no appreciable effect on the weight, balance, structural strength, reliability, operational characteristics, or other characteristics affecting the airworthiness of the product. All other changes are “major changes” (except as provided in paragraph (b) of this section).
 
experimental avionics producers
FYI: No such thing as an "experimental" avionics producer.
21.93 Classification of changes in type design
FYI: has zero to do with replacement parts or alterations as we are discussing at this level.
not be suggesting this path?
They can't as a "producer." Plus Part 3 gets in the way. Only an installer can make those type of determinations per Part 43.;)
 
With that key thought and this definition, the doors of possibilities certainly open quickly. With that in mind, why would experimental avionics producers not be suggesting this path?

Let me put you in the shoes of the avionics manufacturers. Two products come down an identical production line, identical testing, and identical paperwork. One of them is marked with a model number A1234 and is meant for "standard" certificated airplanes. One of them is marked with a model number B1234 and is meant for experimental aircraft. You can sell the A1234 for $200 more just for the difference in model numbers. Your call. What do YOU do?

Jim
 
FYI: has zero to do with replacement parts or alterations as we are discussing at this level.

Why not? What am I missing? That defines what is a minor or major alteration. I pulled it off of the FAA flowchart. And instrumentation change as we are discussing fits within the minor.
 
That defines what is a minor or major alteration.
Not quite. A major/minor change to a type design (Part 21) is not the same as major/minor alteration to an aircraft Part 43). There are major alterations that do not meet the requirements of a major change to type design. Only an STC or ATC via a regional Aircraft Certification Office can approve a major change to type design whereas an FAA ASI can approve a major alteration. And an A&P can sign off a minor alteration. Look over AC 43.210, Figures 3.1 and 3.2 for a better feel of how the process works.
 
certain manufacturers have no certified parts that I am aware of, or only very recently do. Thats who I am talking about.
I can provide you half a dozen that have one production line and two model tag lines. But since part of my income comes from keeping these people happy while signing off stuff on my own, I'm not about to put a bullet target on them. You are incorrect that there are few certain manufacturers have a certificated and an experimental parts line.

By the way I see your avatar as some sort of dune buggy. Mind sharing what your aviation credentials are? Just curious.

Jim
 
You are incorrect that there are few certain manufacturers have a certificated and an experimental parts line.

By the way I see your avatar as some sort of dune buggy. Mind sharing what your aviation credentials are? Just curious.

Jim

I did not say there was certain manufactures with separate lines. To my knowledge, GRT only sells experimental parts. It seems reasonable to me that they might be interested in offering a path to sell their product to the certified market with out the expense of certifying their parts. Maybe its not worth the can of worms it might open. Or maybe they do plan to certify some stuff one day. Thats just an example.

i got my A&P in 2009. I work for a regional airline. Im quite good at my job there, however; it offers no exposure to stuff like this. I purchased my own Cessna last year and earned my PPL last month. Im trying to learn.
 
I did not say there was certain manufactures with separate lines. To my knowledge, GRT only sells experimental parts. It seems reasonable to me that they might be interested in offering a path to sell their product to the certified market with out the expense of certifying their parts. Maybe its not worth the can of worms it might open. Or maybe they do plan to certify some stuff one day. Thats just an example.

i got my A&P in 2009. I work for a regional airline. Im quite good at my job there, however; it offers no exposure to stuff like this. I purchased my own Cessna last year and earned my PPL last month. Im trying to learn.

I think the thread here is that GRT (for example) does NOT have to "certify" (whatever that means) their stuff to let you put it (for example) into your Cessna. Your A&P allows you to do that, which is where this whole thread took a turn about two pages ago.

Congrats on the A&P. I cherished my 5 years with the airlines and wouldn't have traded it for anything. With one rather disastrous day. Our airline (PSA) was an airline during the day and a training organization at night. College was my day job, PSA my night and weekend gig. I had to come home and tell the wife that I had been transferred from the radio shop to the traning group for two months. Training the most beautiful women I've ever seen in my life ... DOZENS of them ... in "stew school". At 2 am. Every night for two months. That did NOT go over too well at home.

JIm
 
Congrats on the A&P. I cherished my 5 years with the airlines and wouldn't have traded it for anything. With one rather disastrous day. Our airline (PSA) was an airline during the day and a training organization at night. College was my day job, PSA my night and weekend gig. I had to come home and tell the wife that I had been transferred from the radio shop to the traning group for two months. Training the most beautiful women I've ever seen in my life ... DOZENS of them ... in "stew school". At 2 am. Every night for two months. That did NOT go over too well at home.

JIm

Was that when the "stews" wore the go-go boots and mini skirts?
 
You mean like these students of mine (but I cannot remember their names from that long ago). I think the one on the bottom stair was Margie, but that was almost 60 years ago. Each of them averaged between 3 and 5 serious marriage proposals a week from young businessmen traveling the West Coast flyway.PSA.jpg
 
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Mike Busch confirmed what weirdjim said on Sat., with a bit more detail in this EAA webinar. https://www.eaa.org/videos/5464397691001
One point that stood out for me was that it is a simple log book entery to "replace" a wing, but a "major alteration" requiring a 337 for "repair" a wing.
Here's another relevant one: https://www.eaa.org/videos/4461567987001

My A&P/IA required that we file a 337 for replacing the windshield in our C182A - but since it just gets scanned and filed, why not?
 
Just because I'm nosy, did you leave the center vertical support strap in, or replace it with a one-piece windshield?

Jim
 
FWIW: I believe the gist of the latter portion of the thread was to install an item as a minor alteration vs obtaining approved data. Considering you completed a 337 for your windshield "replacement", you either had approved data or obtained it.
 
Just because I'm nosy, did you leave the center vertical support strap in, or replace it with a one-piece windshield?

Jim
I don't think it's nosy - just comparing notes. I kept the center strap because it doesn't bother me, and was far less work. You need the thicker windshield to remove the strap, and that requires replacing the support at the top to allow for the thicker windshield. What I did do was spring for the UV/IR blocking gray tinted one, and am glad we did.
 
FWIW: I believe the gist of the latter portion of the thread was to install an item as a minor alteration vs obtaining approved data. Considering you completed a 337 for your windshield "replacement", you either had approved data or obtained it.
And I don't think we are getting through, Bell. You can install the item on a logbook entry as a minor alteration or do 337 for a "major" alteration for which you need "approved" data.

What a circus.

Jim
 
FWIW: I believe the gist of the latter portion of the thread was to install an item as a minor alteration vs obtaining approved data. Considering you completed a 337 for your windshield "replacement", you either had approved data or obtained it.
No - we submitted the 337 because the IA doesn't understand the difference between a replacement with an approved part and a major repair. I didn't either at the time ...
 
the difference between a replacement with an approved part and a major repair.
??? Don't quite follow your posts. These are completely separate topics. A part replacement has zero to do with a repair and in a number of cases same with an alteration. 337s are only needed with major alterations or repairs. Plenty of approved windshields are installed under a simple logbook entry. Perhaps a few more details with your replacement may clear your point up?
 
??? Don't quite follow your posts. These are completely separate topics. A part replacement has zero to do with a repair and in a number of cases same with an alteration. 337s are only needed with major alterations or repairs. Plenty of approved windshields are installed under a simple logbook entry. Perhaps a few more details with your replacement may clear your point up?
Although it was a simple replacement, the IA insisted on a 337 - which is clearly inappropriate in this case. Regardless, he wanted it before he'd sign off the replacement, so we filed one. My point is that there is a LOT of misunderstanding of the rules out there (here). He has been an IA for at lest 30 years if not longer. He attends the IA refresher classes at OKC frequently (and invited me along a couple of times), byt still errors way over on the side of regulatory caution most of the time.
 
I wish one of us would start an IA refresher course with OUR point of view. Going to the FAA for an IA refresher course is like asking an attorney if you need advice.

How about it, Bell. Ready to start an online refresher course? Of course, the refresher has to be "approved" by the FAA. Fat chance that is going to happen.

JIm
 
My point is that there is a LOT of misunderstanding of the rules out there
Quite true. Especially when you get into the alteration side. Any chance your replacement window had an STC associated with it? A lot of people will swear that every STC requires a 337--old, young, IAs, and owners. It's how they were taught so it follows it must be true. Same goes for the TSO vs non-TSO issue. Regardless, it boils down to what the installer, your IA, wants in order to sign his name to it which as a mechanic I perfectly understand. There have been things I wanted done before I signed that tweaked a few people, but usually I have a justified reason in writing to back me up. Did your IA give you a legit reason for the 337 other than he simply wanted it? What approved data did he use?
 
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How about it, Bell. Ready to start an online refresher course?
Ha. Why worry about getting it approved. If you get your little internet based T/shooting thing going why not just add-on a "maintenance reality" portal. I'm sure with Dan T's 2 cents thrown in we might even get a few people edumacated on those taboo subjects like electrical parasitic drains or installing non-TSO equipment. Who knows, maybe we will even give the infamous MB a run for his money.:eek:
 
Quite true. Especially when you get into the alteration side. Any chance your replacement window had an STC associated with it? A lot of people will swear that every STC requires a 337--old, young, IAs, and owners. It's how they were taught so it follows it must be true. Same goes for the TSO vs non-TSO issue. Regardless, it boils down to what the installer, your IA, wants in order to sign his name to it which as a mechanic I perfectly understand. There have been things I wanted done before I signed that tweaked a few people, but usually I have a justified reason in writing to back me up. Did your IA give you a legit reason for the 337 other than he simply wanted it? What approved data did he use?
It came with a PMA certificate, I didn't know enough to question him at the time, but it did seem strange, though that big hole in front did look "major" enough, as well as those hundreds of little machine screws with nylock nuts.
 
It came with a PMA certificate
That sounds about right. So, no STC? Curious, look on the back of your windshield 337 (Box/Section 8) and, if you can, post the approved references listed. FYI: I respect every mechanic's reasoning to complete a 337 or whatever. Period. I'm just interested in the details.;)
 
The entirety of section 8:

"Removed old crazed and hazy windshield and replace with new LP Aero Plastics windshield , part number LP #315 UV-SG. PMA number 0713000-24. Installed per Cessna maintenance manual and FAR Part 43.13-1B, section 3-24."

That's it.
 
That's it.
Old school. Back when PMA parts were going mainstream the OEMs revolted on several levels decrying PMA parts were "junk" because they were cutting into their, OEM, lucrative market. This pushed the FAA to counter. While there are other guidance docs the one below is the one I use. It basically states PMA parts "interchangeable" with the original OEM parts for which they are PMA approved. Some people still CYA even though a 337 is not required by the rules. Perhaps forward the doc below to your IA for his review.
https://rgl.faa.gov/Regulatory_and_...V=1&SearchFuzzy=0&Start=1&Count=1000&vs=Curr#
 
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