FAA Advisory Circular 23-27

Timbeck2

Timbeck2

Final Approach
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Timbeck2
Since I'm relatively new here, this probably has been posted before. But if you get the chance I highly recommend reading it. It would seem that in a rare lucid moment, the FAA acknowledges that parts for pre-1980 aircraft are getting hard to come by and that our little purchases from the "aerospace" aisle in the local parts store in a lot of cases can be legal. ;)

What spawned this is the search for an alternator belt for my 1970 PA-28. I found that Piper took a silver sharpie, put their part number on a Gates 9335 belt (also fits a 1986 Honda Civic CRV if you need one) and sold it for 3 times the price.

Other interpretations are highly encouraged.
 
Timbeck2 said:
Since I'm relatively new here, this probably has been posted before. But if you get the chance I highly recommend reading it. It would seem that in a rare lucid moment, the FAA acknowledges that parts for pre-1980 aircraft are getting hard to come by and that our little purchases from the "aerospace" aisle in the local parts store in a lot of cases can be legal. ;)

What spawned this is the search for an alternator belt for my 1970 PA-28. I found that Piper took a silver sharpie, put their part number on a Gates 9335 belt (also fits a 1986 Honda Civic CRV if you need one) and sold it for 3 times the price.

Other interpretations are highly encouraged.
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I totally think that's great... But remember, when Piper sketched the part number on it, they also took the liability risk. So, it IS worth something.... Probably not 3X.
 
I get that...people are sue happy and people need to cover their ass BUT if I'm reading AC 23-27 right...and which is the reason I'm asking for other's opinions here, a log entry similar to this would be legal.

Piper alternator belt part number XXX_XXX replaced with Gates part 9335 as the Piper part is no longer being made.


There are guidelines listed that provide guidance for replacement parts listed in the AC.
 
There is another way and perhaps reads a bit better in the logbook. Since a silver sharpie part number is an intrinsic part of the fabrication of the belt, take a silver sharpie and put "Part # 123435678ABC rev:D" on the belt and now you are the manufacturer.

FAR 21.303 (b)(2) allows the owner of an aircraft to manufacture parts for their own aircraft. Now the logbook reads "Replaced alternator belt with p/n 12345678ABC Rev:D per FAR 21.303 (b)(2)".

Nobody is going to take the time to look all that crap up and you are just as legal either way.

(The green funnyface is what you get when you do "colon D" (i.e. :D))

Jim
 
Yep. Wheel bearings now can be bought at local bearing house and used legally stead of 4x price OEM...which came off same line.


Sent from my iPad using Tapatalk
 
I'm pretty sure you are going to crash into a school for the children of personal injury attorneys.
 
The airline I work for produces some parts for our own aircraft. Since we have no PMA, we would be in violation to use the word "manufacture." We fabricate. And, we fabricate using manufacturers engineering drawings that have specifications that my department ensures are met. Taking an automotive belt and identifying it as an aircraft part is not "producing," "fabricating," or "manufacturing." It is counterfeiting.
 
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GlennAB1 said:
The airline I work for produces some parts for our own aircraft. Since we have no PMA, we would be in violation to use the word "manufacture." We fabricate. And, we fabricate using manufacturers engineering drawings that have specifications that my department ensures are met. Taking an automotive belt and identifying it as an aircraft part is not "producing," "fabricating," or "manufacturing." It is counterfeiting.
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If you are manufacturing parts for resale, you must have a PMA.


If you are manufacturing parts (fabricating) to an approved drawing that are consumed in a repair, you don't need PMA.

Seat tracks and floor beams are machined everyday from blank extrusions which part numbers are found in the structural repair manuals. These are not for sale but cut specifically for the repair in work.
 
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If the part manufacturer's part number is identical to a part which has an aircraft builder's part number added to, in addition to the original part number, it can be substituted on an a/c certified prior to Jan 1, 1980 per AC 23-27. Just because the aviation manufacturer adds an additional part number, it doesn't change it.


This space intentional left blank.
 
N3368K said:
If the part manufacturer's part number is identical to a part which has an aircraft builder's part number added to, in addition to the original part number, it can be substituted on an a/c certified prior to Jan 1, 1980 per AC 23-27. Just because the aviation manufacturer adds an additional part number, it doesn't change it.
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The part approved for aircraft couldn't possibly go through extra quality inspections?
 
AC 20-62E

b. Acceptable Parts. The following parts may be found to be acceptable for installation on
a TC’d product:
(1) Standard parts (such as nuts and bolts) conforming to an established industry or
U.S. specification.

f. Standard Part. Is a part manufactured in complete compliance with an established
U.S. Government or industry-accepted specification, which includes design, manufacturing, and
uniform identification requirements. The specification must include all information necessary to
produce and conform to the part. The specification must be published so that any party may
manufacture the part. Examples include, but are not limited to, National Aerospace Standard
(NAS), Air Force/Navy (AN) Aeronautical Standard, Society of Automotive Engineers (SAE),
Aerospace Standard (AS), Military Standard (MS), etc.

OWT never cease to exist....
 
GlennAB1 said:
The part approved for aircraft couldn't possibly go through extra quality inspections?
Click to expand...


Apparently the FAA doesn't think so according to 23-27


Jim R
Collierville, TN

N7155H--1946 Piper J-3 Cub
N3368K--1946 Globe GC-1B Swift
N4WJ--1994 Van's RV-4
 
AC 23-27 "...if you use the means described in this AC, you must follow it in all respects." "This AC also provides guidance about the data required to gain Federal Aviation Administration (FAA) approval for making these substitutions."

If that isn't quality oversight, I don't know what is.
 
Scan of the AC regarding belts.

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Funny you should post that. The belt I replaced was a Goodyear Gatorback with no silver sharpie marking on it from Piper.

I guess the guy who owned it before me did the same thing but no log book entry.
 
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