Be careful when you buy used STC'd parts.

stratobee

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stratobee
It's a steep learning curve in aviation at times.

I've just encountered a problem that was news to me. When you buy an STC'd part, say from someone parting a plane out, even though you have all the STC paperwork and installation manuals and parts list, you still need a written authorisation letter from the STC holder to be legal as part of FAR 21.120. And the STC holder can charge you whatever he wants for that, or deny you that letter of authorisation and then you're not legal to put the part on.

I just bough an updated STC brake system for my plane. The STC holder wants 10% of what the new part would have cost from him to issue the paperwork. This I have no problem with. But he also wants to inspect it and overhaul it before he issues that letter of authorisation. You can see that there is a slight conflict of interest here - there is no real incentive on his behalf to make this economically viable now as he's out of a sale. Might not be the case in this scenario and I believe most people are good and fair, but just wanted to give people in the same position a heads up.

Thread lightly and do your research and contact STC holder before you buy a used part.
 
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Or as with S-TEC, the outright won't sell you an STC for their used equipment, nope, gotta buy a new one. I had a 60-2 found at a good price in a corroded out 310 but it's completely useless.
 
It's his intellectual property so he's within his rights to require a fee to use it.

Not sure about the overhaul part. If he commits to a specific fee for that it may be worthwhile.
 
Would it be possible for you to use a field approval of some kind in lieu of an STC?
 
Or as with S-TEC, the outright won't sell you an STC for their used equipment, nope, gotta buy a new one. I had a 60-2 found at a good price in a corroded out 310 but it's completely useless.
On a certified aircraft.
It should still be usable on EAB or E-LSA, right?

Jim
 
It's his intellectual property so he's within his rights to require a fee to use it.
I don't know that I agree. Sure, there may be a patent that would prohibit someone from copying their design. But that's not what we have here. We have a product that they put into the stream of comerce, and a subsequent purchaser for value. The only reason they have any say is the regulations require the OEM to issue some paper work. So, the government has granted them some additional bargaining power over and above possessory rights, and the intellectual rights protected through patent law.

Just my thoughts.
 
Or as with S-TEC, the outright won't sell you an STC for their used equipment, nope, gotta buy a new one. I had a 60-2 found at a good price in a corroded out 310 but it's completely useless.

when did this change?
Cobham S-TEC offers STC paperwork for their used equipment.
 
He had to jump through hoops at the FAA to get the STC. That cost him time and money. Would you expect him to get no return on his investment?
 
He had to jump through hoops at the FAA to get the STC. That cost him time and money. Would you expect him to get no return on his investment?

Well, there was compensation when the product was sold initially. Assuming we are only talking about time for the paperwork to install the used item in a second or subsequent aircraft, I think it fair that he receive additional reasonable compensation for this additional time. But, given that this isn't a free market, and the government has essentially granted a sort of monopoly, it strikes me as a bit unfair if he can unilaterally set any price, or unreasonably deny it altogether. And, if he is going to get some more, it would seem that that should reset the clock on any statute of repose defense to a product liability claim. Of course, issuing the paperwork alone might be enough to re-set the clock on the statute of repose (depending on the state). So that would also warrant some additional compensation.
 
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Lotta generalizations going on in here but pretty much how it works.
 
I don't know that I agree. Sure, there may be a patent that would prohibit someone from copying their design. But that's not what we have here. We have a product that they put into the stream of comerce, and a subsequent purchaser for value. The only reason they have any say is the regulations require the OEM to issue some paper work. So, the government has granted them some additional bargaining power over and above possessory rights, and the intellectual rights protected through patent law.

Just my thoughts.

You are entitled to the product you bought used. You now own it and can use it as you see fit, within the scope of whatever regulations govern that activity.

If some future use of it requires paperwork for the way you intend to use it, then you have to pursue the paperwork as well. It's not a monopoly, as any company (or even you yourself) could go through the same process they did and acquire the STC. Once you did so at considerable expense you are probably not going to be willing to give it away...

It's the nature of the beast when dealing with certified aircraft.
 
. It's not a monopoly, as any company (or even you yourself) could go through the same process they did and acquire the STC.

Interesting. I thought the manufacture would have to do this.
 
Or as with S-TEC, the outright won't sell you an STC for their used equipment, nope, gotta buy a new one. I had a 60-2 found at a good price in a corroded out 310 but it's completely useless.

I don't think that's any longer the case. IIRC, the stc is like $3.5k, plus they require that the oh the equipment before issue. Each servo is $1.7, Have no clue what they would charge for the gyro and computer.
 
Well, there was compensation when the product was sold initially. Assuming we are only talking about time for the paperwork to install the used item in a second or subsequent aircraft, I think it fair that he receive additional reasonable compensation for this additional time. But, given that this isn't a free market, and the government has essentially granted a sort of monopoly, it strikes me as a bit unfair if he can unilaterally set any price, or unreasonably deny it altogether. And, if he is going to get some more, it would seem that that should reset the clock on any statute of repose defense to a product liability claim.

If you want to pay for the engineering data to get any mod FAA approved you don't have to buy HIS/HER STC.

For instance:

Joe Blow holds the STC to install SATCOM SYSTEM 1 but you don't like where the boxes and antennas are mounted in his STC data. You are free to pay for the engineering to get your own STC approved or pay for engineering for "STC deviations" (you still have to buy his STC for the deviation route)
 
The FAA is a little sticky on autopilot installations in normally certificated aircraft. S-TEC has you over a barrel and they know it.
 
Would it be possible for you to use a field approval of some kind in lieu of an STC?

Absolutely not, the FAA has no right to give away what does not belong to them, and will not do it.
 
I don't know that I agree. Sure, there may be a patent that would prohibit someone from copying their design. But that's not what we have here. We have a product that they put into the stream of comerce, and a subsequent purchaser for value. The only reason they have any say is the regulations require the OEM to issue some paper work. So, the government has granted them some additional bargaining power over and above possessory rights, and the intellectual rights protected through patent law.

Just my thoughts.

To apply that STC to your aircraft requires a 337 to enter it into the aircraft's history records at OKC, The STC number must be in block 8 of the 337, and proof that you own the rite to use it must be kept by the aircraft owner, the STC paper work will show the aircraft "N"umber on its title page.

Using the STC with out permission of the STC owner can cause the issue to be contested in civil court.
 
OTOH, DAC publishes it's stc paperwork on the web, and all you need to do is download and fill it out to install a used dac 31. Not all stc owners have their hands out.
 
To apply that STC to your aircraft requires a 337 to enter it into the aircraft's history records at OKC, The STC number must be in block 8 of the 337, and proof that you own the rite to use it must be kept by the aircraft owner, the STC paper work will show the aircraft "N"umber on its title page.

Using the STC with out permission of the STC owner can cause the issue to be contested in civil court.

And lack of proper authorization to use the STC will make your aircraft legally UN-airworthy. Major repairs and modifications require that a 337 be filed. No 337, you're not legal. No STC authorization, no valid 337 can be filed. It could also get you in trouble withe the feds for flying an un-airworthy plane.
 
Ultimately this procedure is detrimental to everyone. Because it means if you part out a plane, your most valuable parts might not be worth a single dime in case the STC holder has gone out of business, is deceased or not playing ball. Imagine the due diligence we're all saddled with all of a sudden.

I know for sure I will have to look long and hard at buying used STC'd parts from now on. Even at 50 cents on the dollar, that part might end up costing you a lot more than a new part. Or be completely unusable.
 
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Ultimately this procedure is detrimental to everyone. Because it means if you part out a plane for parts, your most valuable parts might not be worth a single dime in case the STC holder has gone out of business, is deceased or not playing ball. Imagine the due diligence we're all saddled with all of a sudden.

I know for sure I will have to look long and hard at buying used STC'd parts from now on. Even at 50 cents on the dollar, that part might end up costing you a lot more than a new part.

I don't see how it's detrimental. If you have the STC, then the parts are what you need. If you don't have the STC, then you really don't have a way of knowing (without STC documentation) that you truly have the right parts.
 
And lack of proper authorization to use the STC will make your aircraft legally UN-airworthy. Major repairs and modifications require that a 337 be filed. No 337, you're not legal. No STC authorization, no valid 337 can be filed. It could also get you in trouble withe the feds for flying an un-airworthy plane.

Show me the regulation on who is responsible for insuring who bought what?

and

how that determines/ relates to airworthiness.

show me the regulation.
 
I don't see how it's detrimental. If you have the STC, then the parts are what you need. If you don't have the STC, then you really don't have a way of knowing (without STC documentation) that you truly have the right parts.

What would you do when you bought a set of fabric wings, and they are covered with ceconite, completed on an STC applied to another aircraft that was scrapped and de-regestered?

The answer is very easy.
 
What would you do when you bought a set of fabric wings, and they are covered with ceconite, completed on an STC applied to another aircraft that was scrapped and de-regestered?

The answer is very easy.

Fabric wings? Ceconite?

400pancake_bunny.jpg


:)
 
Fabric wings? Ceconite?

old fabric aircraft wings came from the factory with cotton and dope, when you recover with ceconite it requires a STC for the system you used.

when you replace old wings with ones re-covered with Ceconite that had the STC recorded on another aircraft you must move that STC to your aircraft.

How do you do that ? it is the same method that would be used, to use STCed parts recorded on another aircraft.
 
Ultimately this procedure is detrimental to everyone. Because it means if you part out a plane, your most valuable parts might not be worth a single dime in case the STC holder has gone out of business, is deceased or not playing ball.

If that is the case the STC is in public domain, and any one can use the intellectual property.


Imagine the due diligence we're all saddled with all of a sudden.

Not a problem, when you know the STC number you can get a copy of the paper work.


I know for sure I will have to look long and hard at buying used STC'd parts from now on. Even at 50 cents on the dollar, that part might end up costing you a lot more than a new part. Or be completely unusable.

Not in all cases, when the STCed replacement parts were bought from a legal source you can ask the STC holder to move their records for these parts to your N Number. some will, some won't, or charge a fee to do this.
 
Ultimately this procedure is detrimental to everyone. Because it means if you part out a plane, your most valuable parts might not be worth a single dime in case the STC holder has gone out of business, is deceased or not playing ball. Imagine the due diligence we're all saddled with all of a sudden.

I know for sure I will have to look long and hard at buying used STC'd parts from now on. Even at 50 cents on the dollar, that part might end up costing you a lot more than a new part. Or be completely unusable.


You make it sound like a huge issue and its really not, but you must know what you are doing. It goes both directions too. Some STC holders have an LOA on their website that says "if you own the equipment you have permission to use the data". Others want big bucks for any papers.
 
Maybe not, but I'm sure there must be more than me that didn't know this. I've been an aircraft owner for 4 years now, and this was all news to me.
 
There is two SEPERATE things being discussed here and they are not the same things.

An STC is a specific approval to modify an aircraft in the manner spelled out in the installation drawings. This IS NOT approval for making and selling parts which would require a PMA.

A PMA'ed part may or may not require a SEPERATE approval for installation such as an STC. PMA = parts manufacturing approval, often says which parts they are a direct replacement for.


Just because one guy STC'ed the installation of an "off the walmart shelf" Keurig coffee maker doesn't mean you can't install it your own chosen way with a different approval.

More often than not, it's doesn't make economic sense to pursue said approval.
 
There is two SEPERATE things being discussed here and they are not the same things.

An STC is a specific approval to modify an aircraft in the manner spelled out in the installation drawings. This IS NOT approval for making and selling parts which would require a PMA.

A PMA'ed part may or may not require a SEPERATE approval for installation such as an STC. PMA = parts manufacturing approval, often says which parts they are a direct replacement for.


Just because one guy STC'ed the installation of an "off the walmart shelf" Keurig coffee maker doesn't mean you can't install it your own chosen way with a different approval.

More often than not, it's doesn't make economic sense to pursue said approval.

I do not see this as two issues, when the parts involved are listed in the STC they are authorized to be used. no matter if they are PMAed or not.

STCs are 1 method of placing an aircraft in its properly altered condition as required by the term " airworthy "
 
The STC holder being "apparently" out of business does not "put the STC in the public domain." There are always successors. We've got a few Navion STCs that the society has been trying to pick up but there's no real economic viability for us to pay any significant amount for them.
 
Maybe not, but I'm sure there must be more than me that didn't know this. I've been an aircraft owner for 4 years now, and this was all news to me.

It actually makes sense when you think about it. Otherwise, all you've got is a bunch of parts.

Similarly, I don't think the STC holder is being too unreasonable in saying he'll give you the paperwork, but needs to see/overhaul the parts first. If I had an STC, I would probably do similarly.
 
Personally, I think the stc shouldbe closer to a patent, whereas it protects the property for a set period of time then expires. There are a lot of orphan stc's that cause grief.
 
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