The International Cessna^® 170 Association

uh12b wrote:Richard
Thank you for the reply.

I thought you could only get a Yellow Tag from a Certified Repair Station. The reason I am asking is because an associate had his gear straightened and all he got back with it was an NDT report.

uh12b

Wou'r right...Are you going to hang the gears.....or am I?.....I need a yellow tag......What do you need?....Brad

A little news as I am finally getting around to pulling my gear...
As of 3/31/09:
-PPOnk doens't do gear OH's and doesn't sell gear.
-XP Mods doesn't exist anymore, (800) 819-9270 is disconnected. They have morphed into T&D Aerospace (509) 881-8919 and want $1500 for gear OH.
-North Sound Aviation has had their most recent number (360) 826-3962 disconnected. Does anyone have any other means of contact for these folks?

I will have a gear-off meltdown if I have to pony up that kind of scratch for a few degrees and the magnaflux warm-fuzzies.

Todd
N1409D

What exactly is a gear overhaul? Where do you find the specifications and criteria for that procedure? Exactly what is entailed with a simple leaf spring?
An NDT report is a good thing if it confirms no cracks. Plastic media paint-strip, NDT test for cracks, Shot peen according to the prescribed process (The shot peen specification is to be Almen intensity of 0.012 to 0.016 with 330 steel shot.), paint and reinstall. Exactly what part of that process produces a "yellow tag"? Nada. It's an NDT test, shot-peen, and refurbish. Ordinary A&P sign off. If NDT was done by a cert. repair sta., then their documentation would be good for me.

archerw wrote: -North Sound Aviation has had their most recent number (360) 826-3962 disconnected.

Todd
N1409D

No real loss, no one ever answered it anyhow.

I don't think there is a need to shot peen unless there's been removal of material in the shot peen area. So the maintenance is really clean, check for cracks and restore the protective coating (paint).

gahorn wrote:What exactly is a gear overhaul? Where do you find the specifications and criteria for that procedure? Exactly what is entailed with a simple leaf spring?
An NDT report is a good thing if it confirms no cracks. Plastic media paint-strip, NDT test for cracks, Shot peen according to the prescribed process (The shot peen specification is to be Almen intensity of 0.012 to 0.016 with 330 steel shot.), paint and reinstall. Exactly what part of that process produces a "yellow tag"? Nada. It's an NDT test, shot-peen, and refurbish. Ordinary A&P sign off. If NDT was done by a cert. repair sta., then their documentation would be good for me.

That does not address a gear leg that is "bent" as mine was

I will look to see if North Sound included a yellow tag when mine were returned.

c170b53 wrote:I don't think there is a need to shot peen unless there's been removal of material in the shot peen area. So the maintenance is really clean, check for cracks and restore the protective coating (paint).

Correct. I didn't mean to imply that it needs to be done if ordinary inspection is all that is performed. I was attempting to point out that there is no prescribed "overhaul" procedure for this landing gear and therefore a "yellow tag" is superfluous.

(I should split this topic because it's gone beyond the original topic, having morphed into "yellow tags".)

YELLOW TAGS are wildly misunderstood, in my opinion. They rarely provide the information actually required for determining airworthiness or traceablity as required for a mx release. (see Part 43, Appdx B) Most "yellow tags" only give you the name of the shop or CRS and a reference to a W.O....none of which provides any true basis of approval for return to service. (What process was used in the "repair"?, what parts were replaced?, what service bulletins were satisfied? etc etc. ??) Most "yellow tags" don't even provide the part's total-time in service, or cycles. So what good is it other than to tell you who to call next time you need one?

What we are really wanting when we ask for a "yellow tag" is EITHER a FAA Form 337 or a MAINTENANCE-RELEASE. And the only folks that can provide a Maintenance-Release in lieu of an FAA Form 337 is a Certified Repair Station (CRS). They've come to be known as "yellow tags" (although I always thought they should be GREEN....which actually only means the object is a candidate for possible repair. RED tags mean the object is condemned. I'd prefer that RED tagged items be defaced or cut in half. That way there'd be fewer of them on fleabay posing as "as removed" aircraft parts.)

If you have your landing gear "overhauled" by anyone, then have them provide a FAA Form 337 describing the actual work performed, indicating the data they used to perform it, and stating that the component is approved for return to service. (You'll never get a time-in-service or cycle-count on these things, but that is what we're supposed to keep track of. If you can get the total time on the original airframe that is generally considered to also be a good estimate of the number of cycles on gen. aviation light airplanes unless they were in student training service.)

As for the original topic of this thread, if anyone has difficulty obtaining the above information from a repair station, then simply notify the FSDO in the region and ask for their "assistance."

If a gear was "bent"... then depending upon how far it was bent... if more than a few degrees it'd need to be straightened and probably annealed/re-hardened and shotpeened, etc. and tested for cracks (NDT). If that work were performed then it should be documented with either a 337 or a mx release describing all those processes and releasing it for service. (Doubtful if all that were done, as it'd be less expensive to replace with another used gear.)