Airworthiness shop or Repairman for Wing Tank Repair

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8296
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Name: George D
Aircraft Type: 1946 C-120
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Re: Airworthiness shop or Repairman for Wing Tank Repair

Post by 8296 »

Thanks Edd

It has been a long time since I have heard that name but remember them from the (my) past. I give it a try and see what they might add to this conversation.

George
8296
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Name: George D
Aircraft Type: 1946 C-120
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Re: Airworthiness shop or Repairman for Wing Tank Repair

Post by 8296 »

As they use to say "No Joy!" I called Yingling and as expected they are not a source for this repair effort. I am just thinking out loud here but to do some of the "leg work" required here for an AI who might have to approve the use of say a Wag Aero supplied filler neck assembly is the regional DAR the FAA agency that would be the final approval authority for this type of repair? I do not want to have to put the burden on the AI who has to make the final field approval decision for the use of a non certified part. Again, if push comes to shove I'll put salvaged tanks in the wings and be done with it but until fully discouraged (too remote a location for a repair, cost, or frustration) then I'll try to go new.
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6643
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Re: Airworthiness shop or Repairman for Wing Tank Repair

Post by 6643 »

I think you're running into "analysis paralysis". Let the person who's doing the repair decide. The rules have a lot of loop holes in them that you are allowed to exploit. There is an AC on choice of materials to repair older planes. I personally see no issue with using a pre-fabricated fuel filler neck of like construction and quality to repair a 75 yer old fuel tank. Also, since it doesn't have a part number, it is unrealistic to expect you can buy it from Cessna. Think of it more like a raw material than a part.
4004
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Re: Airworthiness shop or Repairman for Wing Tank Repair

Post by 4004 »

I agree completely with John Cs comment above. Another FAA justification comes into play - "owner produced part" to repair his own aircraft. One of the criteria listed for justification is "economic" consideration. I may have commented here recently about a Bonanza item that cost approx $4000 that we had fabricated by very qualified machinist for approx $100. From your profile, you are certainly qualified to make the decision that the "owner produced" part from WagAero is satisfactory. I listened to the late Bill O'Brien, FAA discuss this issue at an IA seminar. In the process, the owner has to be involved, and he said the "owner" becomes the final QC ( quality control) inspector to allow the item for his aircraft. FWIW
a64pilot
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Re: Airworthiness shop or Repairman for Wing Tank Repair

Post by a64pilot »

As an A&P I/A I would have no issue installing an owner produced part if it was airworthy.
IF and only IF you the owner made a logbook entry like what it suggested in the following article. That absolves me of facing the FAA one day as I’m accused of using an unapproved part.

https://www.aviationpros.com/home/artic ... aintenance

However it maybe tough to claim that buying something from Wag-Aero constitutes an owner produced part.
Quite a few vendors with other aircraft are selling parts that they claim to be owner produced, they send you a drawing or specifications etc and have you sign it and return to them.
That’s not really owner produced so I think eventually the FAA will come down on owner produced parts. Believe it or not but they are actually intended for the airlines and we sort of weren’t left out of the reg. If done IAW the reg your fine though,it’s these flaky vendors that I think may get some attention.

In this case were I the A&P or IA involved, I’d take the Wag -Aero neck and tank to a professional welder and have it welded, I’d make the log book entry as repaired fuel tank by welding in a replacement aluminum fuel tank filler neck, leak check OK.


The referenced article is a good article and I think will answer many if not most questions, just read the whole article, not just part of it.
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6643
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Re: Airworthiness shop or Repairman for Wing Tank Repair

Post by 6643 »

a64pilot wrote: Fri Jun 25, 2021 1:31 pmIn this case were I the A&P or IA involved, I’d take the Wag -Aero neck and tank to a professional welder and have it welded, I’d make the log book entry as repaired fuel tank by welding in a replacement aluminum fuel tank filler neck, leak check OK.
Exactly! The filler neck isn't the part, the tank is the part. The filler neck is the material you use to effect the repair.
n140f
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Re: Airworthiness shop or Repairman for Wing Tank Repair

Post by n140f »

Hello, I have a 1946 C140. The white sealant that was applied to the inside of the tank has begun to peel off. After getting many smaller pieces out of the sumps, we decided to remove the entire sump and clean the "O" ring. What we found was a huge amount of the while sealant was blocking the sump and potentially clog the screen. So much so that we decided the tanks have to come out and be cleaned.

Does anyone know where I might get that done, and almost more importantly, is there a 337 that would allow for a metal cover over the tank, similiar to a C150?

My wings are Ceconite, and we will have to cut that to remove the tanks.
I'd love to see if someone else has done this, so we could get guidance and field approval data.
any Ideas?

Thanks, Molly
2066
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Re: Airworthiness shop or Repairman for Wing Tank Repair

Post by 2066 »

n140f wrote: Mon Jul 26, 2021 5:02 pm Hello, I have a 1946 C140. The white sealant that was applied to the inside of the tank has begun to peel off. After getting many smaller pieces out of the sumps, we decided to remove the entire sump and clean the "O" ring. What we found was a huge amount of the while sealant was blocking the sump and potentially clog the screen. So much so that we decided the tanks have to come out and be cleaned.

Does anyone know where I might get that done, and almost more importantly, is there a 337 that would allow for a metal cover over the tank, similiar to a C150?

My wings are Ceconite, and we will have to cut that to remove the tanks.
I'd love to see if someone else has done this, so we could get guidance and field approval data.
any Ideas?

Thanks, Molly
Molly, you'll prob get a better answer than I can give...but, I believe there's a structural issue with replacing the fabric over tanks with aluminum sheet. There may be acceptable procedure, but I'm not aware of an STC or "field approval" -- not saying that there isn't one, however. I suggest you contact Lorraine or Ken Morris @ Taildragger Aviation (www.taildraggeraviation.com) as they have lots of experience/expertise in this area and are just super helpful folks. Feel free to PM me if you need additional contact info. other than their "contact us" on the website. Mac
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