337 form

Per FAR 21.117:

(b) A supplemental type certificate consists of—

(1) The approval by the FAA of a change in the type design of the product; and

(2) The type certificate previously issued for the product.

If it has an STC it is changing (amending) the original type certificate and needs a 337 filed.



-VanDy
 
Exactley do you think a company would spend all the money on getting an STC approved if their product could be installed as a minor mod without an STC?
Click to expand...

Yes, because the STC is great for marketing.

It means you can sell the product to installers who do not want, or cannot, read, and/or cannot (or don't want to) take any risk in determining whether the alternation is minor or major.

With an STC, there is no comeback on the installer or the IA, provided the STC has been complied with.
 
Please read my post above and explain how you can change the type design and type certificate of an aircraft and it still be a 'minor alteration?'



peter-h said:
Yes, because the STC is great for marketing.

It means you can sell the product to installers who do not want, or cannot, read, and/or cannot (or don't want to) take any risk in determining whether the alternation is minor or major.

With an STC, there is no comeback on the installer or the IA, provided the STC has been complied with.
Click to expand...




-VanDy
 
peter-h said:
Yes, because the STC is great for marketing.

It means you can sell the product to installers who do not want, or cannot, read, and/or cannot (or don't want to) take any risk in determining whether the alternation is minor or major.

With an STC, there is no comeback on the installer or the IA, provided the STC has been complied with.
Click to expand...

And references to the FAR, Advisory Circular, whatever would be great as well.


-VanDy
 
VanDy said:
And references to the FAR, Advisory Circular, whatever would be great as well.
-VanDy
Click to expand...

Well, the FAR is 43- A, and the AC is 43-18.
I can install a circuit to power a new instrument. and call it a minor alteration.
I can repair up to 2 bays in a fabric wing and call it a minor repair.
I can strip all the paint off the aircraft and polish it with only a log book entry.

Any change to the aircraft that is not called out in FAR 43-A as a major, can be construed as a minor.

Who by FAR is the person who decides if the maintenance is a major or a minor?
 
Who by FAR is the person who decides if the maintenance is a major or a minor?
Click to expand...

An IA, or a Part 145 Repair Station, AFAIK.

Or the FAA ;)
 
Tom-D said:
Well, the FAR is 43- A, and the AC is 43-18.
I can install a circuit to power a new instrument. and call it a minor alteration.
I can repair up to 2 bays in a fabric wing and call it a minor repair.
I can strip all the paint off the aircraft and polish it with only a log book entry.

Any change to the aircraft that is not called out in FAR 43-A as a major, can be construed as a minor.

Who by FAR is the person who decides if the maintenance is a major or a minor?
Click to expand...
Ok so the original question was does adding an STC to the TC require you to have a 337 filled out and sent in. The answer is yes!
Tom, 43-18 is manufacturing parts and does not cover STC installs. I see you have provided examples of minor repairs that don't need a 337, great but that has nothing to do with the original question. YOu yourself said earlier in this thread that an STC is a change in TC and requires a 337, are you going back on that now or did you forget what we were talking about in this thread?
 
flyingmoose said:
Ok so the original question was does adding an STC to the TC require you to have a 337 filled out and sent in. The answer is yes!
Tom, 43-18 is manufacturing parts and does not cover STC installs. I see you have provided examples of minor repairs that don't need a 337, great but that has nothing to do with the original question. YOu yourself said earlier in this thread that an STC is a change in TC and requires a 337, are you going back on that now or did you forget what we were talking about in this thread?
Click to expand...
I answered the thread creep question, I don't see that as contradictory to the answer to the OPs question.

An STC is by nature a major alteration, and does require a 337 to enter that into the history records of the aircraft/engine or appliance.

FAR 43-A defines the other requirements of a major alteration.

The decision (Major/Minor) is not required to be made by the IA, many owners and A&Ps bring me the 337s to return to service. That decision is made by the person doing the work.
 
VanDy said:
Please read my post above and explain how you can change the type design and type certificate of an aircraft and it still be a 'minor alteration?'
-VanDy
Click to expand...

If it truly changes the type design and type certificate, it needs an STC but the FAA in the past has approved STCs for just about anything that people submitted even though they didn't change the TC.
 
When you take a 337 to the IA to return your aircraft to service after the installation, what other paper work needs to accompany it?
 
the FAA in the past has approved STCs for just about anything that people submitted even though they didn't change the TC.
Click to expand...
Exactly; you can get an STC for a different type of self adhesive plastic for the tail number :)

This is the big problem. Lots of US manufacturers have been getting STCs as a marketing exercise.

So, just because Product X comes with an STC does not mean it is a Major Alteration.

With a product like that, the preferred installation route (for a dumb installer) is probably going to be to fill in the 337 and send it off to AFS-750. But such a "bogus" STC can just be ignored.
 
peter-h said:
Exactly; you can get an STC for a different type of self adhesive plastic for the tail number :)

This is the big problem. Lots of US manufacturers have been getting STCs as a marketing exercise.

So, just because Product X comes with an STC does not mean it is a Major Alteration.

With a product like that, the preferred installation route (for a dumb installer) is probably going to be to fill in the 337 and send it off to AFS-750. But such a "bogus" STC can just be ignored.
Click to expand...

See this post:

VanDy said:
Per FAR 21.117:

(b) A supplemental type certificate consists of—

(1) The approval by the FAA of a change in the type design of the product; and

(2) The type certificate previously issued for the product.

If it has an STC it is changing (amending) the original type certificate and needs a 337 filed.



-VanDy
Click to expand...


And remind me how an faa approved change to a type certificate by definition of FAR 21.117 can be a minor alteration.


-VanDy
 
Tom-D said:
I answered the thread creep question, I don't see that as contradictory to the answer to the OPs question.
Click to expand...

My question regarding references was to Peter-h's reference to STC's being able to be a minor alteration...


-VanDy
 
peter-h said:
So, just because Product X comes with an STC does not mean it is a Major Alteration.

With a product like that, the preferred installation route (for a dumb installer) is probably going to be to fill in the 337 and send it off to AFS-750. But such a "bogus" STC can just be ignored.
Click to expand...

I don't think I agree. If the product has an STC, a 337 must be filed, period. That's the rules with an STC.
It doesn't matter if the product would otherwise meet the definition of a minor modification.

I could come up with adhesive lettering for N-numbers, and they could be applied with a log entry. But once I get an STC, then the 337 must be filed.
I could sell two versions of the product, one with the STC and one without. If you buy the STCd version, then a 337 is required.

At least that's my reading.
 
I strip the paint from an aircraft that was painted at the factory, then polish the aircraft.

major or minor.

why?
 
Tom-D said:
I strip the paint from an aircraft that was painted at the factory, then polish the aircraft.

major or minor.

why?
Click to expand...

What does that have to do with 'installing' an STC?


-VanDy
 
murphey said:
I've been reading thru Part 43 and am baffled. When is a 337 required to be submitted? Installed an STC'd strobe (Whelen) and there's an argument among some of the folks around the airport. With the STC, isn't it merely a logbook entry by the A&P?

Another ongoing battle - someone (not me) is claiming that a 2 pound weight difference requires the 337. This is completely illogical.
Click to expand...

To bring the original question back up...


-VanDy
 
VanDy said:
What does that have to do with 'installing' an STC?


-VanDy
Click to expand...

When you figure out the answer to my question you will have figured out the answer to the OPS question.

It is in FAR 43- A

AS far as the STC argument, they are automatic 337 filing, there is no argument, it is how the alteration is entered into the history records.

It matters not, how the the aircraft was changed how little the difference, it does by FAR rule change the aircraft. ANY change to the TCDS is a Major alteration.

See FAR 21.117
 
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I could come up with adhesive lettering for N-numbers, and they could be applied with a log entry. But once I get an STC, then the 337 must be filed.
I could sell two versions of the product, one with the STC and one without. If you buy the STCd version, then a 337 is required.
Click to expand...

[my emphasis]

I find it hard to believe, because nothing (except a lot of time wasted) stops me from getting an AML STC for the adhesive, and if I get that then everybody sticking those numbers on will have to file a 337 because the STC exists?

I absolutely do not believe that the FAA's granting of an STC means something is a Major alteration. They grant it because somebody has applied for it and fulfilled the requirements.
 
peter-h said:
[my emphasis]

I find it hard to believe, because nothing (except a lot of time wasted) stops me from getting an AML STC for the adhesive, and if I get that then everybody sticking those numbers on will have to file a 337 because the STC exists?

I absolutely do not believe that the FAA's granting of an STC means something is a Major alteration. They grant it because somebody has applied for it and fulfilled the requirements.
Click to expand...
Well,, first things first, I do not believe the FAA would give you an STC for a chemical.

But with that said, once you have completed the engineering, done the testing to develop the intellectual property, you are entitled to the STC to protect that property.
 
Tom-D said:
When you figure out the answer to my question you will have figured out the answer to the OPS question.

It is in FAR 43- A

AS far as the STC argument, they are automatic 337 filing, there is no argument, it is how the alteration is entered into the history records.

It matters not, how the the aircraft was changed how little the difference, it does by FAR rule change the aircraft. ANY change to the TCDS is a Major alteration.

See FAR 21.117
Click to expand...

VanDy said:
Per FAR 21.117:

(b) A supplemental type certificate consists of—

(1) The approval by the FAA of a change in the type design of the product; and

(2) The type certificate previously issued for the product.

If it has an STC it is changing (amending) the original type certificate and needs a 337 filed.



-VanDy
Click to expand...



-VanDy
 
But with that said, once you have completed the engineering, done the testing to develop the intellectual property, you are entitled to the STC to protect that property.
Click to expand...
OK.

Let me go off on another tangent.

Let's say there is plenty of prior use of this adhesive (or whatever) either as a minor alternation or as a field approval.

Then I get an STC for it.

The intellectual property aspect of that STC is not just a little dubious, wouldn't you say? ;)

And the intellectual property aspect of that STC is now enforced by the FAA which nowadays require a letter of authorisation from the STC holder if an STC is used as Approved Data.

I am no expert on this. I just know these bits which is why I am asking here, so I learn more.

But take 1 example: Garmin AML STCs. The last one I saw had a note on the cover saying the STC is authorised to be used only by Garmin Authorised Dealers.

Yet, the products are being installed all over the place, by freelance installers, in situations where it is a Minor alteration (as most GPS installs are where there is no autopilot interface, etc). So the STC is being disregarded, and IMHO correctly because it isn't needed; an STC is no more than a high grade of Approved Data for supporting a 337 and if no Major alteration is taking place then ipso facto no STC is needed.

Another point is that here in Europe there are loads of EASA STCs being generated which are little more than a compilation of the back pages (the wiring diagrams) from FAA approved installation manuals. To suggest such an STC represents IP is a bit distasteful IMHO.

Yet anybody can get an STC for anything that meets the FAA requirements.
 
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