Tyre substitution

[peter-h]

I have seen it claimed that on Part 23 aircraft only the specific tyres listed in the IPC may be fitted.

Allegedly, the only way to fit different ones (even of the same size etc) is via a 337 field approval (or an STC if there is one).

Reportedly, the FAA has enforced this at a particular dealer, forcing him to change a load of tyres on turboprops.

Any views?

 

[Geico266]

Tyres = tires

 

[SCCutler]

I use Desser retreads. Great tires.

Don't know the full installation basis, but my A&P installed them.

 

[Graueradler]

I would think that if you deviate from the Type Certificate, it would be legit to expect you to be able to show why that was OK. On a retract, you might find a tire that would fit the rim but cause problems with fitting or not in the wheel well. As speed and weight go up, other tire characteristics than just fitting on the rim become important. If it was important enough for an engineer to determine what to put on in the first place, some one needs to have identified the critical characteristics and evaluated an intended replacement to determine that the replacement meets or exceeds those requirements. Usually, no body but a nitpicker is going to be concerned if you put a same size 6 ply on a fixed gear piston single that originally had 4 ply tires. If you went to a 2 ply instead of a 4 ply, you would raise more of a question. In either case, the paperwork requirement should be the same.

P.S. Have vacationed not far from you (Bournemouth) but many years ago. At least I didn't need a thesaurus to understand "tyre"

 

[poadeleted20]

That's true in terms of the tire specifications (ply, size, etc.) but not by manufacturer other than the tire having to be an FAA approved aircraft part. So, if you want to replace your book-specified 4-ply tires with 6-ply, you'd need an STC or field approval on a 337, but to replace your Goodyear Flight Special 6-ply 6x6.00 tires with Michelin Aviator 6-ply 6x6.00's, no further approval is required.

 

[Tom-D]

I have seen it claimed that on Part 23 aircraft only the specific tyres listed in the IPC may be fitted.

Allegedly, the only way to fit different ones (even of the same size etc) is via a 337 field approval (or an STC if there is one).

This is true for the CAR produced aircraft also.

The parts that make up the aircraft on the production certificate for the make and model, are what the FAA views as the standard, any change to that standards requires approval.

now let the discussion begin as to, "is it a minor alteration or a major."

 

[Tom-D]

That's true in terms of the tire specifications (ply, size, etc.) but not by manufacturer other than the tire having to be an FAA approved aircraft part. So, if you want to replace your book-specified 4-ply tires with 6-ply, you'd need an STC or field approval on a 337, but to replace your Goodyear Flight Special 6-ply 6x6.00 tires with Michelin Aviator 6-ply 6x6.00's, no further approval is required.

True so far, Why is that?

 

[poadeleted20]

now let the discussion begin as to, "is it a minor alteration or a major."

Given what it says in Part 43 Appendix A:

(a) Major alterations--
(1) Airframe major alterations. Alterations of the following parts and alterations of the following types, when not listed in the aircraft specifications issued by the FAA, are airframe major alterations:
(vi) Landing gear

...unless you are arguing that the tires aren't part of the landing gear (an argument I don't think the FAA would accept), then using different spec tires would be a major alteration, which requires either an STC or field approval, but a 337 either way. OTOH, using a different brand with the same specs would not even be an alteration, since the aircraft remains in conformance with the specifications in the type certificate.

And that should answer both your questions.

 

[Tom-D]

Given what it says in Part 43 Appendix A:
...unless you are arguing that the tires aren't part of the landing gear (an argument I don't think the FAA would accept), then using different spec tires would be a major alteration, which requires either an STC or field approval, but a 337 either way. OTOH, using a different brand with the same specs would not even be an alteration, since the aircraft remains in conformance with the specifications in the type certificate.

And that should answer both your questions.

It's a lot easier than that,, the production certificate is not allowed to state manufacturer, other wise Cessna could require you to use their bolts and nuts.

plus by federal law the manufacturer can not create a monopoly on parts.

 

[Geico266]

I use Desser retreads. Great tyres.

Don't know the full installation basis, but my A&P installed them.

FIFY.

 

[Tom-D]

Quote:
(a) Major alterations--
(1) Airframe major alterations. Alterations of the following parts and alterations of the following types, when not listed in the aircraft specifications issued by the FAA, are airframe major alterations:
(vi) Landing gear

It doesn't say type certificate.

"aircraft specifications" includes the production certificate that is where the list of parts to make up the complete aircraft is located, and where the size and specifications for the appliances is located, not the type certificate.

 

[peter-h]

I can't post the actual text because it was posted on a type specific members-only site (whose owner owns copyright to all posts anyway) but it was reported that a dealer for a certain turboprop (in current production) got busted by the FAA for installing identical-spec tires but of a brand not specified in the IPC, and the FAA forced them to change them.

In addition it was stated that if you have a Cessna Mustang you have to buy the tires from Cessna, due to this issue.

 

[Tom-D]

I can't post the actual text because it was posted on a type specific members-only site (whose owner owns copyright to all posts anyway) but it was reported that a dealer for a certain turboprop (in current production) got busted by the FAA for installing identical-spec tires but of a brand not specified in the IPC, and the FAA forced them to change them.

In addition it was stated that if you have a Cessna Mustang you have to buy the tires from Cessna, due to this issue.

There must be more to that story than we know here.

Remember there are ADs that effect parts replacement. Plus the fact we do not know if the tires installed were aviation tires, that would not be of the type listed as replacements.

 

[peter-h]

It concerns the equivalence of these tires

Michelin 6 ply Aviators
Air Hawk 500-5 6 ply
Goodyear 5.00-5 6 ply Special II, p/n 06-07100
Goodyear Flight Custom III

For "Mustang" in my earlier post, read "Citation".

The aircraft IPC specifies only these (for the main landing gear)

Goodyear:
15x6.00x6 6PR Flight Special II P/N 156E61-3

Michelin:
15x6.00x6 6PR Aviator P/N 061-501-0

I think the main question was whether the Goodyear Flight Custom III is illegal.

 

[peter-h]

The AC quoted is AC 20-41A.

 

[weilke]

The AC quoted is AC 20-41A.

1. PURPOSE: This circular sets forth an acceptable means for complying with the rules governing aircraft equipment installation in cases involving the substitution of technical standard order (TSO) equipment for functionally similar TSO approved equipment.
.
.
.
6. EXCLUDED EQUIPMENT. The substitution procedures provided by this circular should not be used in connection with auto pilots, flight directors, inertial navigation systems, stability augmentation systems, stall prevention systems, tires, wheel-brake systemes, or any other equipment directly affecting flight controls or flight characteristics. Substitutions which affect equipment in the cockpit should be aevaluated by appropriate flight test personnel.

-------------------


The preamble states that it is AN acceptable means to show compliance, I dont believe it is the only acceptable means. The way I understand the works of US regulatory agencies, the final decision what to accept is up to the maintenance inspector. In the case at hand of a part145 repair station, that inspector can indeed use the AC to require the repair station to only use the tires specified in the IPC. The maintenance inspector of YOUR FSDO who walks down a row of parked aircraft and issues maintenance notices may find that the TSOed tire on your aircraft that conforms to size and number of plies is acceptable. It is guidance, not regulation carved in stone.

 

[peter-h]

The preamble states that it is AN acceptable means to show compliance, I dont believe it is the only acceptable means. The way I understand the works of US regulatory agencies, the final decision what to accept is up to the maintenance inspector. In the case at hand of a part145 repair station, that inspector can indeed use the AC to require the repair station to only use the tires specified in the IPC. The maintenance inspector of YOUR FSDO who walks down a row of parked aircraft and issues maintenance notices may find that the TSOed tire on your aircraft that conforms to size and number of plies is acceptable. It is guidance, not regulation carved in stone.

Why don't you post that on socata.org?



From the PM you sent me, you were more than happy about my fate there in 2008, for disagreeing with some people.

 

[weilke]

Why don't you post that on socata.org?

Because I dont get in the middle if my kids, married people or drunks fight either.

From the PM you sent me, you were more than happy about my fate there in 2008, for disagreeing with some people.

That's a long time to hold a grudge. I went back to my PM from '08 and I dont see how you could get the idea that I was happy about your fate there, on the contrary, you were one of the most knowledgeable people on the site when it comes to the aircraft and dealing with the FAA/CAA/EASA interface. I just thought your style of dealing with other forumites was unneccessarily abrasive and detracted from the issues being discussed. It is a loss for the site that you dont post anymore.

Anyway, I emailed an acquaintance who runs a part145 repair station and has been director of mainteance for some charter outfits. He and the PMI supervising his facility do not agree with that binding interpretation of AC 20-41A. From prior discussions with him, his FAA counterpart seems to be a real stickler when it comes to the documentation of 'authority' and 'approved data' for alterations, but when it comes to TSOed consumables, short of the manufacturer saying 'dont use tire X because it is too fat and breaks off switch actuator Z', there is little restriction on what you can use as long as it conforms to the specs.

Fwiw, the airlines mostly fly retreads. I doubt that every retread is on the manufacturers list, but whoever approved their maintenance manual must have accepted whatever data they had and signed off on it.

 

[peter-h]

From what I hear elsewhere, I agree.

The problem is that if you ask enough FSDO inspectors, you will eventually find one who tells you a 337 is needed to put avgas in your tank.

I had several inspectors in one FSDO (east coast) tell me absolutely, no question, that a Sandel SN3500 EHSI is an EFIS product and cannot be installed without an STC. That is completely wrong.

I also had several inspectors in another FSDO (west coast) tell me absolutely, no question, that a KLN94 is not IFR certified. That is completely wrong, too.

Now let's say you are a pilot living in the USA, and an FSDO like that happens to be your local one, what do you do?

FWIW, it goes without saying that EASA loves this sort of thing because it allows them to ridicule the FAA and justify their job creation schemes, feeding business to EASA Part 21 companies (the approximate equivalent of an FAA DER) which then ends up generating yet more work at EASA so it's great for all.

 

[Tom-D]

seeing as you are in the UK dealing with a French built/certified aircraft thru the NY FSDO, I can understand the problem.

 

[weilke]

From what I hear elsewhere, I agree.

The problem is that if you ask enough FSDO inspectors, you will eventually find one who tells you a 337 is needed to put avgas in your tank.

That was my thought when someone suggested that changing your tire is a major alteration involving the landing gear

Now let's say you are a pilot living in the USA, and an FSDO like that happens to be your local one, what do you do?

You move your plane to a friendlier place to have the work done. The shop answers to the fsdo responsible for his geographic location, given the differences in opinion on some stuff, flying the plane 12 miles across the state (and FSDO jurisdiction) line can get things done.

 

[Tom-D]

You move your plane to a friendlier place to have the work done. The shop answers to the fsdo responsible for his geographic location, given the differences in opinion on some stuff, flying the plane 12 miles across the state (and FSDO jurisdiction) line can get things done.

What you should really do is get your ducks in a row, call the FSDO supervisor, and arrange to have a meeting with them and the offending inspector.

I've had to do this twice over the years, but you had best be certain you are right and have the rule to back you up.

and remember that you will still go on that inspector's chit list

 

[weilke]

What you should really do is get your ducks in a row, call the FSDO supervisor, and arrange to have a meeting with them and the offending inspector.

I've had to do this twice over the years, but you had best be certain you are right and have the rule to back you up.

and remember that you will still go on that inspector's chit list

Yup, you can fight city hall, works every time .

 

[peter-h]

seeing as you are in the UK dealing with a French built/certified aircraft thru the NY FSDO, I can understand the problem.

Wasn't me. My tyres (tires) are the Goodyear ones.

And while the NY IFU is indeed the FAA FSDO in charge of Europe (and Africa and the Middle East AFAIK) everybody who can do so avoids dealing with them. It was them who said an EHSI is an EFIS, and anyway they have stopped doing 337s for avionics. They still do some stuff like PRNAV LOAs but are taking best part of a year to sign them.

What I can't help noticing is that I have personally dealt with 3 FSDOs and 2 of them told me complete and utter bull. That's a 33% success rate; not really good. I have also dealt with 2 other FSDOs via local people who helped me out and they were both OK but in both cases it was done face to face.

But it can work the other way.

One man I know of was told by his FSDO that he can install any other engine in his plane which shares a type certificate with the engine certified for the airframe. So off he went and installed a version of an IO540 which is similar (same HP) as the originally certified one. Everybody "knows" this is incorrect but he is OK because he has got it in writing, so they can't bust him. Anyway what he did was completely safe. It would have been quite funny if he replaced a 250HP one with a 350HP twin turbo one, which shares the same TC

And years ago I was told by an FAA inspector (non US based) that a European BRNAV approval includes full IFR approval (approaches etc), which is also definitely wrong. I asked him to put it in writing but that never happened.

It's a minefield...

 

[wabower]

Gulfstream's completion center in Dallas finally gave up and got ferry permits to fly them to LGB for "final completion" and delivery.

That was my thought when someone suggested that changing your tire is a major alteration involving the landing gear



You move your plane to a friendlier place to have the work done. The shop answers to the fsdo responsible for his geographic location, given the differences in opinion on some stuff, flying the plane 12 miles across the state (and FSDO jurisdiction) line can get things done.

 

[Graueradler]

Note to self: Peter H is knowledgeable. In the future, don't waste time posting simple answers to his simple questions.

 

[SCCutler]

Note to self: Peter H is knowledgeable. In the future, don't waste time posting simple answers to his simple questions.

When you said a little, you said a lot there.

If only Bendix King would listen to Peter, they could repair a whole line of servos...

 

[RotorAndWing]

It's a minefield...

As we use to say in the FAA "There are no standards in Flight Standards".