The International Cessna^® 170 Association

While perusing AD notes at FAA.GOV I came across an AD which I'm wondering why it wouldn't also apply to our aircraft which have undergone aileron replacements/repairs:

http://rgl.faa.gov/Regulatory_and_Guida ... &Count=100#

I don't recall mine having cotter pin holes. I think the ends of my hinges are staked to keep the pins in place. (it's a bit inconvenient to go check...) Since all of the airplanes to which this would apply are "later" models, might have Cessna changed the way it secures the pins?

I would certainly include that AD in my inspection process. Note the way the cotter pin is bent to prevent vibration and loosening.

My hinges have cotter pins exactly as the AD describes.

I bought N3415D in July 1983. Aileron hinges were, and still are, staked. When controls were removed for painting in Mena, AR, followed by balance check, in 2006 they were reinstalled using the staking procedure. So, does the AD apply and everyone has missed it? What say you Wingnut?

jlwild wrote:I bought N3415D in July 1983. Aileron hinges were, and still are, staked. When controls were removed for painting in Mena, AR, followed by balance check, in 2006 they were reinstalled using the staking procedure. So, does the AD apply and everyone has missed it? What say you Wingnut?

Well I have a lot of things to say
If your aircraft was painted in July of 83, the AD had not become effective yet (the -22 is the 22nd by-weekly period of the year) But even if it had, just from my reading of the text of the AD it was not applicable to the 170 series.
I will look in to this further, but here is what I do know. The paint shop does not and would not have to remove the hinge pins from the hinge halves to remove the aileron for balance. In fact, the hinges (hinge assemblies, pin and all) must be installed on the aileron for the balance check. To remove the aileron, you just remove the 4 screws in each hinge half that attaches it to the wing.
I recall reading, but don't remember where, that the hinge assemblies where originally crimped (staked), but sometimes the pin slowly "creeps" to the stake and then gets captured and then only rotates on one hinge half. This causes one aluminum hinge half to wear. Then there were the hinge assemblies that were not staked enough, allowing the pin to migrate out. Then the pins that were/are staked to tight causing resistance of movement. We have a 170 in the hangar now with crimped/staked hinges, and they are very hard to move (so much resistance I think it would be noticeable to the pilot) I won't mention the owner's name, but his initials are PAUL I have no idea why the 170 was left out of this AD (there are many other aircraft make/model/SN#'s aircraft that have been left out of AD's that should be included)
I do know if you order a replacement hinge assembly for your 170, from Cessna or McFarlane you will receive hinge assemblies that take a cotter pin, not staked.

oh and I'll edit to add, it wasn't me, in 1983 I was just grunt. I pushed a lot of dust around the hangar with a broom. I felt privileged to air up a tire or hold a bucking bar

I'll add something else. I suspect that a lot of mistakes can be made "in the field". The hinge half that attaches to the wing is fastened with screws. The half that attaches to the aileron is riveted. In "the old" days when a mechanic decided the hinge was sloppy, I'll bet most of them were not rivet drillers/installers, and therefore just attempted a "fix" by replacing the pin and the screwed on half. Of course they would have to re-crimp/stake the pin during this process. Who knows what type tools or processes were used. The imagination conjures all manner of methods. My favorite so far is smashing it in a vise My guess is uniformity of the re-crimping/staking process was less than uniform, and resulted in the problems mentioned in my previous post above. I think Cessna's solution (prompted or not) was to make the pin replacement idiot proof, and subsequent hinges match

I was wrong about the McFarlane hinges. This is what you get

wingnut wrote:I was wrong about the McFarlane hinges. This is what you get

image.jpg

image.jpg

I like them!!

Back to George's original post, and observation, I can't find any info as to why the 170 models (and other models) were omitted from the AD. They were also omitted by the referenced Cessna service letter, although the hinge assy PN listed in same is exactly the same PN shown in 170 IPC
George, you may be on to something. I could not find the preamble quickly so I gave up. To many irons in the fire.

jlwild wrote:I bought N3415D in July 1983. Aileron hinges were, and still are, staked. When controls were removed for painting in Mena, AR, followed by balance check, in 2006 they were reinstalled using the staking procedure. So, does the AD apply and everyone has missed it? What say you Wingnut?

After re-reading the thread, I see I misunderstood when you had the plane painted; in 2006, not 1983. And then I felt real stupid cause I remember your plane and meeting you. Dennis sublet the surface balance to me. My name should be in your logs. I hope it is anyway
If your aileron hinge assemblies are staked (my memory is not that good) they were that way previous to the paint and balance. We do not remove the hinge pin. I will call Cessna tech tomorrow and get an answer. It seems the AD should apply to the models listed "and other models that may have PN# 0523107*** installed". Don't quote me on the PN, that just popped in my head. I will look it up shortly and correct it
***Edit- the part number is 0523807
More shortly.......

The part number call out in the Cessna 170B IPC for the hinge assy is 0523807. This is also the same PN# mentioned in the AD. I'm missing something, is this a trick question George?
A little digging thru the 172 and 182 IPC's show those models also had the same PN 0523807 installed up until (during) the 1985 production year for both models. The 172 series SN# 76256 and up had 0523816-1 hinge assy's, as did post 182 SN#'s 68446 (both during the 1985 production year). SO, because the AD came out in 1983, this doesn't explain anything.
If you try to order a 0523807 from Cessna you will get a 0523816-1.

Jim, the short answer to your question is; Yes, everybody missed it including me. More to follow when I talk to Cessna tech

Thanks Del for all the research! Sorry I got you side tracked from your day job.

This discussion got me to wondering what I have on my '56 172 (Should be identical to B model 170's).
I took a look this morning and each end of all 6 hinge pins have the cotter key's (pins) in them as depicted in the drawing of the AD. Also the firm that painted my plane for me in 2000 had done as Del mentioned by removing the aileron hinges from the wing and upon reattachment they used new hardware.
I recall that one time when I was doing a pre-flight check on my C-140A that one of the hinge pins had worked its way out about a inch. I tapped it back in place and never experienced that again. Those must have been smooth pins with no retainers.

I have been looking at these on all the cessna's I work on since the AD came out. I have yet to see a hinge in distress.