Tire STC?

[reecewallace]

I just replaced the tires which came on my 1956 170b with the same ones, the Goodyear 8.50—6 tires Part # 856T61-1

When I dropped the plane and tires off at the shop, they called me saying they would install the new tires, but wouldn't write it in my tech logs because I did not have the STC.

What do I do here? Is there an STC for these tires, and how do I get one? Does it matter?

Figured I was safe just replacing my existing ones I purchased the plane with the same model, but sounds like it's more complicated than that.

[pdb]

This may be helpful.

https://fadodge.com/wp-content/uploads/ ... ations.pdf

[GAHorn]

This may be helpful.

https://fadodge.com/wp-content/uploads/ ... ations.pdf

x
The comments following are not to disparage the installtion of the 8:50 X 6 tires. They only remark on potential legality details of this discussion.

This has been discussed previously…the problem with the FADodge letter is it specifies “original” 170 wheels…which were Gooodyears…not the Clevelands likely installed.

The problem with the shop is that if they install the tires and don’t make the log (mx record) entry…they are in violation of FAR 43.9 (a).

[mit]

I gave up caring when it comes to 8:50's and if it was 8:00's on Cleveland's. Kind of like back seats.

[wabuchanan]

My shop signed off on them with the FA Dodge letter.

I now have a Field Approval for the Goodyear 26's

[reecewallace]

This may be helpful.

https://fadodge.com/wp-content/uploads/ ... ations.pdf

x
The comments following are not to disparage the installtion of the 8:50 X 6 tires. They only remark on potential legality details of this discussion.

This has been discussed previously…the problem with the FADodge letter is it specifies “original” 170 wheels…which were Gooodyears…not the Clevelands likely installed.

The problem with the shop is that if they install the tires and don’t make the log (mx record) entry…they are in violation of FAR 43.9 (a).

Ok, I’m still at a loss here. What do I do? Is there an STC?

[reecewallace]

I gave up caring when it comes to 8:50's and if it was 8:00's on Cleveland's. Kind of like back seats.

What do you mean?

[GAHorn]

Reece… I believe it could be summarized by saying that most of us feel that owners should be able to accomplish minor alterations without fear of federale vigilanteism. The intricacies of legalese language become stumbling blocks unnecessarily in many cases.
For example, if the phrase FAA included in the FADodge authorization letter “approved due to similarity of application’ were taken to include the use of replacement Cleveland Wheels as it is taken to include the use of different-size tires…. then surely we shouldn’t need special approval to do so.
Unfortunately, seemingly minor alterations sometimes involve hidden or less-than-obvious hazards.

Example: The “original” Goodyear wheels had provisions for brakes that were inside/within the wheel outer structure where the brake mechanism would not interfere with tire sidewalls and would not pose a hazard to wheel rotation from interference. That is not the case with Cleveland wheels where the different disc-braking system is external to the wheel and can contact the tire sidewall and prevent rotation upon landing…or can create drag on take-off due to an under-inflated tire on one side. (which might lead to a runway excursion.)

Subtle differences might make for large unforeseen problems in what might first appear to be a minor alteration.

FAA is unlikely to become involved unless there is an event or accident to attract their attention. However your certificated repairman (A&P or repair station) may not wish to risk their certificate by performing an alteration without clear and specific approval basis.
The most common “regulator” of these sort of things become the insurance underwriters and the risk or liability of owners to injured persons should such alterations come to light in an accident. If an oversized tire should deflate and cause a minor groundloop on taxying…. where your wingtip collided with a corporate jet or a SWA 737… you can bet your un-approved tire swap will become a focal point in the courtroom.

Do you believe the difference between an unapproved 8:50 versus an approved 8:00 tire is worth the risk?
That is the dilemma.

Most of us in that situation would seek a fully-approved method of compliance…. or would simply forgo the risk.

[Bruce Fenstermacher]

Reece, what George assumes you know is that 8:00 tires are approved on the TCDS. But of course the TCDS approval would have been on the original Goodyear wheels, not the Clevelands you likely have. So, if you are in the camp the wheel change doesn't make a difference, then try to persuade your I/A the FADodge letter is good.

There is no STC that comes to mind.

[GAHorn]

Bruce, my Cleveland conversion STC 13GL has an approval note #6 which states the approval data is based on 6:00 X 6 tires. No other size is indicated.

I seem to recall somewhere in these forums this has been a point also…and that discussion IIRC was that Cleveland limited the specific wheel to only the 6:00 tire.. (I do wish the phpBB search routine was more specific but I’ll try to find that discussion.)

I do recall that the STC applies to a number of other models of Cessnas that allow other tire sizes, and that the 6:00 x 6 note on STC 13GL might be in reference only to the braking action data in the STC. “Common sense” should apply one would think…. but maybe FAA is not authorized by GSA to any of that..??

viewtopic.php?f=26&t=13212&p=124948&hil ... ze#p124948 was a discussion in which Metal Master made some helpful comments regarding the FADodge STC also requiring double-puck brakes if the larger tire is installed.

This braking issue may be more than what meets the eye, as the Cleveland STC braking notes are included in order to prove their wheel/brake assy meets the FAA braking-action requirements. There are other comments/opinions which have been made pooh-poohing the import of brakes in this regard…but if a wheel/tire/brake modification doesn’t meet the FAA requirements for aircraft certification then it won’t be approved. What we often overlook is that a Cleveland wheel conversion became popular NOT because people wanted different wheels…. but because they wanted better and cheaper braking. It’s actually a Cleveland BRAKE stc…..


(and while on this topic…. Everyone who has the Cleveland wheels: DO NOT USE the IPC part numbers to select wheel bearings for your Cleveland Wheels. There is a small dimensional difference between the bearings used in the original Goodyear wheels and the Cleveland wheels. Only use the specified bearings for Cleveland wheels.

[voorheesh]

It’s possible that the original poster’s question remains unanswered. The shop who installed the tires did him no favor. IMO, they returned his airplane to service with these tires by completing the installation and allowing him to depart with it. Knowingly performing this work and refusing to properly document it is wrong. So he is now left with an airplane that he knows has a questionable part(s) and no maintenance record. Unacceptable.

Assuming this airplane has been through prior annual inspections with identical tires, it would seem the owner should go back to his IA (as Bruce suggested) and get the new installation entered in the records. I believe the issue regarding different tire size is very minor and probably inconsequential. The attached Atlee Dodge letter might be considered approved data with the accompanying authorization from ACO concerning similar Cessna airplanes. He might ask his IA to seek a field approval. It is not uncommon for an IA to find an aircraft in an altered condition and to make a maintenance entry that the condition is satisfactory, despite the IA not being responsible for the actual work. Remember, however, that IAs have considerable responsibility in making these calls along with the liability.

I hope the OP can resolve without having to discard these tires which would be a shame. For me, the takeaway is to not allow a shop or a technician to work on my airplane unless they are willing to stand by it.

[reecewallace]

Reece… I believe it could be summarized by saying that most of us feel that owners should be able to accomplish minor alterations without fear of federale vigilanteism. The intricacies of legalese language become stumbling blocks unnecessarily in many cases.
For example, if the phrase FAA included in the FADodge authorization letter “approved due to similarity of application’ were taken to include the use of replacement Cleveland Wheels as it is taken to include the use of different-size tires…. then surely we shouldn’t need special approval to do so.
Unfortunately, seemingly minor alterations sometimes involve hidden or less-than-obvious hazards.

Example: The “original” Goodyear wheels had provisions for brakes that were inside/within the wheel outer structure where the brake mechanism would not interfere with tire sidewalls and would not pose a hazard to wheel rotation from interference. That is not the case with Cleveland wheels where the different disc-braking system is external to the wheel and can contact the tire sidewall and prevent rotation upon landing…or can create drag on take-off due to an under-inflated tire on one side. (which might lead to a runway excursion.)

Subtle differences might make for large unforeseen problems in what might first appear to be a minor alteration.

FAA is unlikely to become involved unless there is an event or accident to attract their attention. However your certificated repairman (A&P or repair station) may not wish to risk their certificate by performing an alteration without clear and specific approval basis.
The most common “regulator” of these sort of things become the insurance underwriters and the risk or liability of owners to injured persons should such alterations come to light in an accident. If an oversized tire should deflate and cause a minor groundloop on taxying…. where your wingtip collided with a corporate jet or a SWA 737… you can bet your un-approved tire swap will become a focal point in the courtroom.

Do you believe the difference between an unapproved 8:50 versus an approved 8:00 tire is worth the risk?
That is the dilemma.

Most of us in that situation would seek a fully-approved method of compliance…. or would simply forgo the risk.

Thanks. Like I said, the airplane came with 8.5x6 tires, and it went through annual about one month ago with them on. My AME (Canadian Mechanic) signed off on the aircraft, but told me to replace the tires in the very near future. He did not say anything about them not being certified or any issue—so I thought nothing of it.

So, I ordered the identical tires and had them changed one month later at a different maintenance facility as I recently moved.

Should I just bring the FADodge letter to the maintenance facility and see if they will sign off on it?

[reecewallace]

It’s possible that the original poster’s question remains unanswered. The shop who installed the tires did him no favor. IMO, they returned his airplane to service with these tires by completing the installation and allowing him to depart with it. Knowingly performing this work and refusing to properly document it is wrong. So he is now left with an airplane that he knows has a questionable part(s) and no maintenance record. Unacceptable.

Assuming this airplane has been through prior annual inspections with identical tires, it would seem the owner should go back to his IA (as Bruce suggested) and get the new installation entered in the records. I believe the issue regarding different tire size is very minor and probably inconsequential. The attached Atlee Dodge letter might be considered approved data with the accompanying authorization from ACO concerning similar Cessna airplanes. He might ask his IA to seek a field approval. It is not uncommon for an IA to find an aircraft in an altered condition and to make a maintenance entry that the condition is satisfactory, despite the IA not being responsible for the actual work. Remember, however, that IAs have considerable responsibility in making these calls along with the liability.

I hope the OP can resolve without having to discard these tires which would be a shame. For me, the takeaway is to not allow a shop or a technician to work on my airplane unless they are willing to stand by it.

Thanks for this, helpful information.

As a new aircraft owner, every step in maintenance is a learning process. I know little about STC's, field approvals, and conditional maintenance entries.

If I can get the maintenance facility who installed the tires to sign off with the FADodge letter, or have my AME who did my annual sign off on a conditional approval, am I covered in case of an incident? Anyone willing to chime in on this?

I suppose this is my only course of action?

I had no idea the 8.5x6 were in a grey area of approval, otherwise I would have ordered 8.0s.

[voorheesh]

I can tell you that you need to have this installation entered in the maintenance records by a repair station or certificated technician with a signature indicating return to service. Had you installed them yourself, you could have made the record entry perPart 43 Appendix A (c)(1). But you didn’t do that so I would advise against trying that route ( others may chime in here). In any case, you (owner) are responsible for airworthiness and I would recommend you resolve whether or not these tires are authorized for your airplane.

The issue for a certificated entity is they must insure that the installed part is eligible for your airplane. Usually, that involves documentation such as a PMA or an STC that specifically identifies your airframe. In this case, the documentation (Atlee Dodge letter) specifies Cessna 170, however does not specify the wheel assembly you are probably using. Assuming that the function of the wheel is equivalent between Goodyear and Cleveland (meaning that tire fits and is equally functional on both types), I believe it is reasonable for an IA to approve this installation with reference to the Atlee document because it is based on a finding by the Aircraft Certification Office (ACO). I would recommend the IA also document the airplane has been equipped with these tires before needing replacement and with no prior difficulty noted. The IA could enter this on a 337, sign, cc FAA, and place in airplane records. Another option is to go to your local FSDO and apply for a field approval which would be a good idea if your IA has doubts.

Regarding any worries you might have over liability, I can assure you that, based on your inquiry, you are a conscientious aircraft owner and I seriously doubt anyone will be pointing fingers at you over this. In fact you get credit for being smart enough to ask. I used to investigate aviation accidents for a living and I can tell you it’s highly unlikely that your selection of tires would be identified as a factor in an incident unless they (tires) were clearly defective or were the reason for what happened. It’s possible that an investigator would recognize they are non standard, but unless they were a direct factor it would probably not be an issue. Regarding the FAA role, they have to observe and follow the rules concerning correct parts, but more often than not, they are willing to evaluate and approve alterations such as yours if properly applied for and containing appropriate substantiation. What I’m trying to say is approval in this case seems obvious. The best advice is for you to follow up and get your tires documented. I hope this helps. You are doing the right thing.

[reecewallace]

I can tell you that you need to have this installation entered in the maintenance records by a repair station or certificated technician with a signature indicating return to service. Had you installed them yourself, you could have made the record entry perPart 43 Appendix A (c)(1). But you didn’t do that so I would advise against trying that route ( others may chime in here). In any case, you (owner) are responsible for airworthiness and I would recommend you resolve whether or not these tires are authorized for your airplane.

The issue for a certificated entity is they must insure that the installed part is eligible for your airplane. Usually, that involves documentation such as a PMA or an STC that specifically identifies your airframe. In this case, the documentation (Atlee Dodge letter) specifies Cessna 170, however does not specify the wheel assembly you are probably using. Assuming that the function of the wheel is equivalent between Goodyear and Cleveland (meaning that tire fits and is equally functional on both types), I believe it is reasonable for an IA to approve this installation with reference to the Atlee document because it is based on a finding by the Aircraft Certification Office (ACO). I would recommend the IA also document the airplane has been equipped with these tires before needing replacement and with no prior difficulty noted. The IA could enter this on a 337, sign, cc FAA, and place in airplane records. Another option is to go to your local FSDO and apply for a field approval which would be a good idea if your IA has doubts.

Regarding any worries you might have over liability, I can assure you that, based on your inquiry, you are a conscientious aircraft owner and I seriously doubt anyone will be pointing fingers at you over this. In fact you get credit for being smart enough to ask. I used to investigate aviation accidents for a living and I can tell you it’s highly unlikely that your selection of tires would be identified as a factor in an incident unless they (tires) were clearly defective or were the reason for what happened. It’s possible that an investigator would recognize they are non standard, but unless they were a direct factor it would probably not be an issue. Regarding the FAA role, they have to observe and follow the rules concerning correct parts, but more often than not, they are willing to evaluate and approve alterations such as yours if properly applied for and containing appropriate substantiation. What I’m trying to say is approval in this case seems obvious. The best advice is for you to follow up and get your tires documented. I hope this helps. You are doing the right thing.

Thanks a lot for this detailed explanation. It definitely clarifies a lot of my concerns. When I put so much time, money, and effort into meticulously maintaining and documenting my aircraft, I'm going to have this resolved before I fly it with the new tires.

You're correct—I have Cleveland wheels, so this is where the discrepancy lay.

As I said, I live in Canada, so I'll have to do some research about our equivalents to 337's, field approvals etc. However, I believe there are likely the same processes here.

Cheers