Cessna 172 panel gut job
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SkyDog58
Ejection Handle Pulled
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Canis Non Grata
I would have thought one would have approved data before tearing into it. Maybe that’s just me.
Yes that's what I'm looking for. To do this to a panel where do I start? Do I have to go straight to a DER to get approved data? Will Cessna give the blessing on such work? For those that have done a major panel gut job like the one in the pic by what means are you getting it approved?
Albany Tom
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Well, continuing along in the spirit at which you seem to be heading, I'd say the next step would be to get a big flat piece of aluminum to stick in there, with some holes in it, so that you can ask "hey is this ok?" to whomever the hell you would ask that question to. I think I'd paint it grey.
I think the AP mechanic doing the work is responsible for that, not you.
The 1st place to start, unless you have an A&P certificate, is to find a mechanic who is willing to complete the work and sign it off as needed.
And if they had such a certificate they probably (hopefully) wouldn't be asking.
I'd hazard a guess this is a project someone started, found out they didn't have the skills or certificate to complete, and are looking to sell. Now a perspective buyer wants to know how many amu's it's gonna take.
My guess is the installer either died or had to move on. There are certain things in the pic that indicate the skill set was there to finish it. Of all the projects to pick up on these are the worst. I've done two and shouldn't have done the 2nd one but I was a slow learner back then.
It will take all of them.
Lol, I appreciate all the comments but I think I need to rephrase my question... I'm just trying to learn from those that have done the type of work being done in the pic what process was used to make it legal. I don't believe that an A&P can simply sign this off because it is technically a structural part of the airframe and thus requires a 337. A 337 requires approved data. If this was a repair of the structure we could use 43.13 but this particular pic is far from a repair it is very much in the realm of alteration. At least that's the way I see it, and I could certainly be wrong. That being said, if this falls into a major alteration how do you go about doing it legally? What course should be taken to acquire the approved data required by the 337? Is there only a single course of action? How are the avionics shops getting away with this type of work, STC, field approval?
So to rephrase my question. I'm not asking how to fix this particular aircraft in the pic. I'm asking for help learning the correct process for doing this type of sub-panel restructuring legally and correctly.
Thank you
So to rephrase my question. I'm not asking how to fix this particular aircraft in the pic. I'm asking for help learning the correct process for doing this type of sub-panel restructuring legally and correctly.
Thank you
From a learning standpoint, its no different than any other aircraft alteration. But prior to “gutting” the panel one should determine and obtain any approvals, if needed, before you start work. Not all instrument panel alterations are considered major alterations based on the guidance in Part 1 and Part 43. However, there could be other sub-tasks which are part of the panel modifications that are considered a major alteration.
For example, if you altered the basic design of the electrical system or how a flight control was mounted/supported that would require approved data and a 337. But if the instrument panel itself was not primary structure then that portion would be considered a minor alteration requiring just a logbook entry. So from the Part 43 alteration side, the correct and legal process to alter this panel can range from 100% minor alteration to 50-50% minor/major to 100% major alteration depending on the specific aircraft and installed equipment. But without more info on your posted pic, can’t really offer more specific answers to your example.
Depends on a number of things. But most avionics shops are also a CRS which operate on a different level than an independent APIA with the APIA having more flexibility in his work process than the CRS. As to STCs vs field approvals each has their own requirements. In general, depending on the type of STC, STCs are used for two purposes: to document/approve an aircraft alteration that is beyond the scope of the field approval process per Part 43; or, an STC is used by a vendor to approve their parts/install per Part 21. So depending on the complexity/extent of the alteration, whether an avionics pursues a STC or field approval will be dictated by the specifics of alteration and/or CRS infrastructure.
FYI: Repairs and alterations are 2 separate functions with separate rules/definitions. However, I’ve seen repairs transform into an alteration due to various reasons.
NordicDave
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There is something squirrelly here. Why is the windscreen professionally masked off and the connectors bagged?
Almost no one would tear-out all the avionics and come to a site like this for "what to do next".
5 will get you 10 this is just a picture off the web of a pro shop midway through a complete aircraft rebuild project. New windows, paint, interior, avionics, etc.
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Thank you for taking the time for this response!!
You mention other alterations such as the basic design of electrical system. I've heard much debate over what is major and what is minor in this area too. Perhaps this is the same answer for the panel as well... that there isn't one. at least not one that is cut and dried. I guess to me I have looked at changing hole size etc to be minor and cutting out radio rack etc to be major. But I guess I don't really have any data to back that idea up either. I've had some avionics guys say "we just cut the whole thing out" and then I've had others tell me I can't look at it crossed eyed without calling it a major alteration.
Thank you again for your response it gave me some more to think about. I've been reading over the ACs like 8300. I'm sure all the answers are in an AC someplace
You mention other alterations such as the basic design of electrical system. I've heard much debate over what is major and what is minor in this area too. Perhaps this is the same answer for the panel as well... that there isn't one. at least not one that is cut and dried. I guess to me I have looked at changing hole size etc to be minor and cutting out radio rack etc to be major. But I guess I don't really have any data to back that idea up either. I've had some avionics guys say "we just cut the whole thing out" and then I've had others tell me I can't look at it crossed eyed without calling it a major alteration.
Thank you again for your response it gave me some more to think about. I've been reading over the ACs like 8300. I'm sure all the answers are in an AC someplace
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GeorgeC
The photo is from AOPA.
Salty
Touchdown! Greaser!
This thread is thick with irony. People that didn't bother to read carefully, complaining to someone else (that actually is doing the research first) that they should have done their research first.
Its back... the whole topic was removed yesterday for some reason.
Here's another one. The same question still stands. If you have any input to the actual question it is greatly appreciated. How do I go about making this instrument panel restructuring legal, on paper that is?
What I have learned so far is that some consider this to be primary structure and it can't be touched with a ten foot pole while others consider this to be secondary structure which means it can be treated as a minor alteration.
The primary structure wording doesn't come up in the definition of major alteration but it does come up in the AC for field approvals, I would have to look again at which one as I've been reading through a bunch and they're all blending together. One thing that would sure make it easier is if the manufacturing would declare it secondary structure and maybe this is the answer? Its being done all the time and airplanes aren't falling out of the sky so hopefully they're not all just getting pencil whipped and there is some definitive means of making it legal on paper.
Thank you
Here's another one. The same question still stands. If you have any input to the actual question it is greatly appreciated. How do I go about making this instrument panel restructuring legal, on paper that is?
What I have learned so far is that some consider this to be primary structure and it can't be touched with a ten foot pole while others consider this to be secondary structure which means it can be treated as a minor alteration.
The primary structure wording doesn't come up in the definition of major alteration but it does come up in the AC for field approvals, I would have to look again at which one as I've been reading through a bunch and they're all blending together. One thing that would sure make it easier is if the manufacturing would declare it secondary structure and maybe this is the answer? Its being done all the time and airplanes aren't falling out of the sky so hopefully they're not all just getting pencil whipped and there is some definitive means of making it legal on paper.
Thank you
Why don’t you find an aircraft with the mods you’d like to do and order the FAA document CD and see what method was used to return it to service?
I think part of your confusion may be due to the different methods by which the work can be approved and legal, which ultimately boils down to the decision of the person doing the work and returning it to service.
BTW, I hope the guy who started another thread and was being told that a Cherokee panel couldn’t be rearranged sees that picture.
That's a good idea actually, hadn't thought about a document CD. If it was a log book sign off it wouldn't show up but if it was an STC or field approval then it would.
I do struggle with this a bit. I have had avionics guys tell me that they do this (see pic) to Cherokees all the time. However, I've also had guys tell me that to do this (see pic) would require a 337 and DER data. Just because an A&P signs for it doesn't necessarily mean that it is legal. Or does it?
I hope so too. I didn't see that thread but I'll take a look and see if I can find it. I may not get to a cut and dried answer on all this but I am learning a lot from those who have provided input.
Thank you
WDD
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Interesting. Good for you for asking the question and double checking the requirements. But my approach would be to use a reputable shop and have the AP show me how everything being done was legal and logged, reweighed, etc. I would be assuming that I'm paying for that along with the work.
Found this today, not sure how I missed it before.
https://www.pilotsofamerica.com/community/threads/panel-cutout-as-minor-modification.121431/
https://www.pilotsofamerica.com/community/threads/panel-cutout-as-minor-modification.121431/