Welding

Tom-D

Tom-D

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Tom-D
Is an A&P within his legal authority to weld a engine cylinder.
 
charlie said:
No! Even an FAA certified repair station cannot do it unless they have an appropriate approved process specification. It's a big deal to get that approval.
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That may be true for a repair station.

Where is that stipulation made for A&Ps working in the field?
 
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Tarheelpilot said:
I can’t answer your legal question but I can tell you it sure falls in the category of things I would never do.
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This is true for me too,
IAW 43-A
(2) Powerplant major repairs. Repairs of the following parts of an engine and repairs of the following types, are powerplant major repairs:

(i) Separation or disassembly of a crankcase or crankshaft of a reciprocating engine equipped with an integral supercharger.

(ii) Separation or disassembly of a crankcase or crankshaft of a reciprocating engine equipped with other than spur-type propeller reduction gearing.

(iii) Special repairs to structural engine parts by welding, plating, metalizing, or other methods.

Does it even constitute a major repair? Is a cylinder a structural engine part?
 
brien23 said:
If it is not put in the log it did not happen.
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A&P brings you a cylinder that's been welded what are you going to tell them that makes it illegal?
IF it is not a major repair they can return it to service themselves
65.87 Powerplant rating; additional privileges.
(a) Except as provided in paragraph (b) of this section, a certificated mechanic with a powerplant rating may approve and return to service a powerplant or propeller or any related part or appliance, after he has performed, supervised, or inspected its maintenance or alteration (excluding major repairs and major alterations). In addition, he may perform the 100-hour inspection required by part 91 of this chapter on a powerplant or propeller, or any part thereof, and approve and return it to service.
 
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Tom-D said:
Does it even constitute a major repair?
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Yes on major. But not sure if a plain A&P can perform it. There's specific guidance that includes crankcases also. I think it's in the FSIMS.
 
Bell206 said:
Yes on major. But not sure if a plain A&P can perform it. There's specific guidance that includes crankcases also. I think it's in the FSIMS.
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Then you believe a cylinder is a structural engine part ?
where / how do we determine that?
 
Tom-D said:
Then you believe a cylinder is a structural engine part ?
where / how do we determine that?
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I don't know whether a cylinder is structural or not. I just remember there is/was something written stating it was a major for weld repairs to crankcases and cylinders. I'll have to look for it.
 
Bell206 said:
I don't know whether a cylinder is structural or not. I just remember there is/was something written stating it was a major for weld repairs to crankcases and cylinders. I'll have to look for it.
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Here is what I found in the 8900-
B. Reciprocating Engines. Major and minor repairs to structural parts of reciprocating engines are classified as follows:
1) Major repairs include the following:
· Welding of crankcases,

· Machining operations necessitated by a weld repair,

· Crankshaft grinding,

· Camshaft recontouring and similar complex precision machining,

· Boring of crankshaft and camshaft bosses, and

· Machining of oil pump housings and accessory drive pads following weld repairs.

2) Minor repairs include simple machine operations, such as spot facing, lapping and grinding valves, and reaming valve guides in accordance with the manufacturer’s overhaul and service instructions.

Says nothing about cylinders. --- welding
I get the feeling, that the FAA does not place the importance on the welding as much as the machining after.
 
Tom-D said:
where / how do we determine that?
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AC 33-6: (This advisory circular defines as major repair, any weld repair done on a crankcase or cylinder).
This is the only doc I could find. I seem to recall another doc but it may be buried somewhere or have been removed. The way the AC is written it looks like only a repair station can do the welding but if a plain A&P was set up properly they might be able to get a one-off repair approved by the FSDO.

http://www.faa.gov/documentLibrary/media/Advisory_Circular/AC_33-6_chg_1.pdf
 
Bell206 said:
AC 33-6: (This advisory circular defines as major repair, any weld repair done on a crankcase or cylinder).
This is the only doc I could find. I seem to recall another doc but it may be buried somewhere or have been removed. The way the AC is written it looks like only a repair station can do the welding but if a plain A&P was set up properly they might be able to get a one-off repair approved by the FSDO.

http://www.faa.gov/documentLibrary/media/Advisory_Circular/AC_33-6_chg_1.pdf
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Did I miss it? No where in these ACs do I see where the Cylinder is defined as a structural part.
This AC only discusses the development of the repair. And says that the manufacturer must produce ICAs and manuals.
The only real FAR rule on this is 43-A and it does not include cylinders.

Here's where I am with this, If an A&P brought a welded cylinder to me for approval, They would have to believe it was a major repair, otherwise my bother with me?
So my first question for them would be, "Why do you believe this is a major"?
my second question would be "why should I get in this Liability loop".

The reason for the thread, Antique radial engine cylinders, and the cooling fins get broken, Putting them back is technically a weld repair.
 
Bell206 said:
AC 33-6: (This advisory circular defines as major repair, any weld repair done on a crankcase or cylinder).
This is the only doc I could find. I seem to recall another doc but it may be buried somewhere or have been removed. The way the AC is written it looks like only a repair station can do the welding but if a plain A&P was set up properly they might be able to get a one-off repair approved by the FSDO.

http://www.faa.gov/documentLibrary/media/Advisory_Circular/AC_33-6_chg_1.pdf
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Quote from AC 33-6
1. PURPOSE.This advisory circular (AC) provides guidance to demonstrate compliance with the requirements of Title 14, Code of Federal Regulations (14 CFR) part 33, Airworthiness Standards: Aircraft Engines.

a. It addresses development of weld repairs which are not contained in the engine manufacturer's "Instructions for Continued Airworthiness" (Maintenance Manual). It provides guidance to clarify the areas which should be addressed by an applicant's repair procedure, and/or substantiating data when seeking an approval for weld repair of aluminum crankcases or cylinders of piston engines.

b. This advisory circular also includes information on critical areas of welding, qualifications of welder's, inspection techniques, the thermal processes, and technical data required. This advisory circular references industry and military specifications which are acceptable for use by repair stations as approved data.
 
I wouldn’t sign it off Tom. If he thinks it’s a minor repair then he can sign it off if not he needs to send it to someone authorized to make the repair
 
Tarheelpilot said:
I wouldn’t sign it off Tom. If he thinks it’s a minor repair then he can sign it off if not he needs to send it to someone authorized to make the repair
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What would you do when the cylinder is already back in service and the aircraft is being annulled? and there is no return to service entry for the weld repair. nor is there any 8030- paper work for the cylinder when it was reinstalled?
 
Tom-D said:
Did I miss it?
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Here is the AC part that defines the cylinder weld is a major repair. It references the old 8300.10 in the beginning but I believe the text from 8900 above is the same.

3. RELATED READING MATERIAL.

a. Directive. FAA Order 8300.10, Airworthiness Inspector's Handbook (11/88).

(1) Volume 2, Chapter 1 describes requirements for approved data; and

(2) Volume 4, Chapter 7 specifically addresses repairs on reciprocating engines and lists welding of crankcases as major repair. (This advisory circular defines as major repair, any weld repair done on a crankcase or cylinder).

Tom-D said:
If an A&P brought a welded cylinder to me for approval
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From this context I would think the question would be moot. For one, if Junior showed up at your shop with a weld repaired cylinder and his 337 didn't have Block 3 stamped and signed, or if he didn't have a signed 8110-3 approving the repair data there would be nothing for you to RTS. Secondly, Junior shouldn't even have gone to your shop. Based on all the circumstantial guidance I believe Junior would have to work at a 145 shop in order to have an approved Process Specification to weld repair the cylinders as it appears only repair stations with a specialized weld rating can do it. Either way nothing for you to sign.

Tom-D said:
What would you do when the cylinder is already back in service and the aircraft is being annulled? and there is no return to service entry for the weld repair. nor is there any 8030- paper work for the cylinder when it was reinstalled?
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Add the item to your List of Discrepancies for the owner.
 
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Tom-D said:
What would you do when the cylinder is already back in service and the aircraft is being annulled? and there is no return to service entry for the weld repair. nor is there any 8030- paper work for the cylinder when it was reinstalled?
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That’s a very personal decision I guess. I think if I believed the repair was done correctly i might be willing to not see the repair. Otherwise the cylinder would have to come off either for inspection by a repair facility or replacement which sounds difficult in your situation because it’s antiquated. If there were log entries by another guy returning it to service as a minor repair it would make life easier as an IA doing the annual later. It’s all about how much liability exposure you want. If the weld is at the base of the fins right up against the barrel I would be worried about how the weld was accomplished and the potential for cracking and failure if they embrittled the area by the weld. It really depends a lot on how good of a welder was doing the work and whether or not they knew enough to maintain the integrity of the cylinder. The easy answer is no. Anything else gets complicated.
Fun times.
 
Bell206 said:
Here is the AC part that defines the cylinder weld is a major repair. It references the old 8300.10 in the beginning but I believe the text from 8900 above is the same.
(This advisory circular defines as major repair, any weld repair done on a crankcase or cylinder).
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Les we forget, an AC can not supersede a FAR. the FAR does not say it is a major.

The whole question is contingent upon if the cylinder is a structural part of the engine.

When ECI was building cylinders they all came with a 337 applying ECI's STC, each had a S/N and were treated as if they were an accessory.
when an AD comes out on cylinders it is based upon cylinder make and model not the engine.
as far as I can see they are always treated as a separate entity.

So I'm not certain what's the correct interpretation.
I will say that if a weld repair is a major repair to an engine, it will get complicated when you swap cylinders from one engine to another.
 
Can the person who welded the cylinder show documentation that defines the process used as acceptable to the administer as required by the fars?

Did the person performing the repair document it as required by 43.9?

Bob
 
Tom-D said:
Les we forget, an AC can not supersede a FAR. the FAR does not say it is a major.

I will say that if a weld repair is a major repair to an engine, it will get complicated when you swap cylinders from one engine to another.
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And lest we forget no FAR can supersede a Title 14 CFR. All FAA guidance is hierarchical and far from inclusive. Otherwise they would not need LOIs, Orders, Notices, Handbooks, ACs, etc. to further guide the user whether that be an ASI or an A&P. All Federal regulations work this way.

Since the FAR does not specifically address the cylinder structural question but the AC defines it as major repair, the AC becomes the reference in force. This is how the performance rules in 43.13 get their foundation: OEM manuals/ICAs… or methods acceptable to the Administrator. And an AC is acceptable.

Its situations when zero FAA written guidance can be found that are troublesome. Those instances require direct talk with a FSDO, MIDO, or ACO. But in this case since the AC declares it a major repair it would take an LOI or other administrative act to disavow it. The Feds always have the legal burden of proof to show something an A&P uses is not acceptable.

As for swapping cylinders with major repairs/337s between engines, it is not complicated. I know more on turbine engines so I’ll use this example. Some turbines are modular and the individual modules (e.g., compressor, gearbox, power turbine) are often separately repaired --as with our cylinder--and are sent out for installation on different engine assys.

The module arrives with the 337 Block 6&7 signed (2 copies) but Blocks 1, 2, and 5 are blank. After the module is installed Blocks 1, 2, and 5 are completed and the 337 disposed of as needed. If that same module is removed in the field and installed on another engine assy, the original 337s will be pulled and sent with the module. A separate 337 will be used to record the new Block 1, 2, and 5 data and forwarded with a copy of the original 337. And yes there is acceptable FAA guidance on this—but no FAR.

This is how I’ve used and seen the system work for my entire career. But it was definitely easier 30 years ago.
 
cylinders are not modules. modules have maintenance records that travel with them. no so cylinders. I built T-56 modules for 12 years and made the entries in these records every day.
If a cylinder weld repair is recorded on a 337, it would be required to be done as an appliance (see block 6) If it is an Appliance, how can it be a structural part of the engine?

I believe that is why the FAR does not say "Crankcase and Cylinder" all other reference given deal with how to comply with FAR 33. and do not defining what the cylinders are.
When a cylinder is repaired by a CRS, it will have a 8030-3 when repaired by any one else it is simply an entry to return to service.

good conversation thanks.
 
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If I ever saw an entry stating "#4 cylinder repaired", I would want to know what was done to repair it.
If | ever saw an entry stating "#4 cylinder head welded", certified by Joe Blow, that would be a show stopper for me. That is a very speciallized repair that can have some very serious consequences and I would not be comfortable certifying an annual with something like that installed. I don't care if it is an appliance or not.
 
JAWS said:
If I ever saw an entry stating "#4 cylinder repaired", I would want to know what was done to repair it.
If | ever saw an entry stating "#4 cylinder head welded", certified by Joe Blow, that would be a show stopper for me. That is a very speciallized repair that can have some very serious consequences and I would not be comfortable certifying an annual with something like that installed. I don't care if it is an appliance or not.
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What would you do/think, If you saw a cylinder on a Old Warner 125, that had some fins replaced? not all the fin just the tips about the size of a quarter?
 
Tom-D said:
not all the fin just the tips about the size of a quarter?
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Curious. Did a Warner have missing fin area limits and allow blending of the area? Or would would a repair like that be done for strictly aesthetics?
 
Tom-D said:
What would you do/think, If you saw a cylinder on a Old Warner 125, that had some fins replaced? not all the fin just the tips about the size of a quarter?
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is it a safety of flight issue?
 
I would have to research that to be sure. Lots of questions. When was it done? Who did the work? What does the original manufacturer allow? Etc, etc, etc.

Off the top of my head, I believe Lycoming and TCM allow for a certain number of fins to be missing, depending on location. The typical repair is to trim a damaged fin and dress it much like a prop - no stress risers. What a true antique engine allowed or not, who knows. It still needs to be airworthy to fly.
 
Bell206 said:
Curious. Did a Warner have missing fin area limits and allow blending of the area? Or would would a repair like that be done for strictly aesthetics?
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No, Warner says nothing.
 
JAWS said:
I would have to research that to be sure. Lots of questions. When was it done? Who did the work? What does the original manufacturer allow? Etc, etc, etc.
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If there is nothing in the log about it how would you tell?
 
Tom-D said:
If there is nothing in the log about it how would you tell?
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Tom, you keep changing the scenario.
If I found welding done on an engine cylinder and it wasn't documented, that would be an issue worthy of more investigation. What else am I not being told?

Maybe this airplane should be in a museum?
 
JAWS said:
That is a very speciallized repair that can have some very serious consequences and I would not be comfortable certifying an annual with something like that installed. I don't care if it is an appliance or not.
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Putting a fin back on a cylinder with a TIG is about as simple as it gets.
 
JAWS said:
Tom, you keep changing the scenario.
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I simply answer questions as the thread creep allows.

read the thread carefully, there is enough in evidence to answer the question.
 
Hey....I can help wit dat if you like. :D

I have a big phone book....:D
 
1-800 who-cares
 
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