No STC paperwork on an old modification - Deal breaker?

kujo806

Pre-takeoff checklist
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kujo806
I have been testing the waters of aircraft ownership for a little while and recently came across a nice plane that seemed to have a lot going for it. The owner said he has owned it for about 5 years, and it had a third window mod and extended baggage compartment mod. He said that is how he bought it, and he has looked through the books extensively and can't find the documentation on it. He was not sure when it had been done, but he didn't do the mod since he had owned it. He volunteered all this information and wasn't trying to avoid the issue at all. I was wondering how big of a deal something like that is. Is it something that a ramp check or annual could flag and create an issue, or is it a water under the bridge scenario where it has been like that so long, no one cares?
 
I'm guessin it's a Beech Bonanza from the 50s. He either went with the factory later model window, or he got one of the STCs. Frankly, I would have the work inspected carefully, and if it seems ok it wouldn't break the deal.

You have little to no fear from the ramp check perspective, but from the annual perspective, this could be a real big deal. The IA that needs to inspect the plane has to account for a non-standard window and baggage panel. Most of them are not well versed enough in the model designation to know when the larger bag bay and third window were put in place. This is why the plane has been going through annual after annual without it being squawked. Technically, a smart IA would catch this, and without the STC paperwork it would have to be all undone, or you could try to source the STC from the vendor if they are still in business and have it inspected against the STC docs. If you are lucky, when you get the CD from the FAA, it'll be on there, and you can just recreated the STC. If it's not in the logs, it won't have the STC, and someone just fudged it from a later model plane. The bulkheads are all there, and the window frame and stuff is pretty easy to do as well.

Is the short triangle third window, or the long tapered one?
 
This particular example is an early 60's Debonair with the tapered third window. I am curious about situations like this in general. I have a feeling I may run into it again on different planes that I look at. Maybe it won't be the same mods, but similar circumstances.
 
Could also easily be a Cessna 180, in which case we're talking about a real airplane.;)
I'm guessin it's a Beech Bonanza from the 50s. He either went with the factory later model window, or he got one of the STCs. Frankly, I would have the work inspected carefully, and if it seems ok it wouldn't break the deal.

You have little to no fear from the ramp check perspective, but from the annual perspective, this could be a real big deal. The IA that needs to inspect the plane has to account for a non-standard window and baggage panel. Most of them are not well versed enough in the model designation to know when the larger bag bay and third window were put in place. This is why the plane has been going through annual after annual without it being squawked. Technically, a smart IA would catch this, and without the STC paperwork it would have to be all undone, or you could try to source the STC from the vendor if they are still in business and have it inspected against the STC docs. If you are lucky, when you get the CD from the FAA, it'll be on there, and you can just recreated the STC. If it's not in the logs, it won't have the STC, and someone just fudged it from a later model plane. The bulkheads are all there, and the window frame and stuff is pretty easy to do as well.

Is the short triangle third window, or the long tapered one?
 
Could also easily be a Cessna 180, in which case we're talking about a real airplane.;)

And once again you show just how wrong you can be. ;):wink2::sad::):rolleyes:
 
I wouldn't let it be a deal breaker, it is too easy to cure the problem of missing paper work.

The FAA may have the 337s documenting this or not, if not, submit the 337s and up date the history files.
 
This particular example is an early 60's Debonair with the tapered third window. I am curious about situations like this in general. I have a feeling I may run into it again on different planes that I look at. Maybe it won't be the same mods, but similar circumstances.

The Bo/Deb are prolly the most highly modified GA plane in the fleet, although I'm sure the 172 would be a contender. It's quite likely that if you shop the Bo/Deb family you will run into this again. What has been done in your case, is that many years ago, some enterprising owner found a dead Bo in the bone yard with the bigger bag bay, and long third window intact. They scavenged all the bits from the airframe, and walked them over to your Deb and installed it all without a lick of paperwork. It looks factory, so therefore it must be factory. I would go looking back in the logs for a new W&B calculation which would give you an idea of maybe when the work was done. Or, it's entirely possible they guy could have just bagged the new W&B calcs in the book and flew on into the sunset with the mods, guessing that the weights wouldn't be significant enough to matter.

Here's another issue. Now that you know, and the owner knows, technically there is a requirement for him to now 'come clean' and have the work investigated at annual. One could even argue that the plane is 'not airworthy' based on the fact it does not meet it's Beech type designation without the requisite STC in the logs. I'm no stickler for this kind of stuff, but sure as heck I would have the work inspected very carefully and get an IA to acknowledge that the work is non-standard. Whether they would sign it off as AW is a big challenge. Doubt you'll find the STC for it anywhere, and I'm pretty sure that although it was all factory Beech in a later model, the SN from your airframe in question is not suitable to upgrade in the field. However, in early Bo's the factory did go so far as to make a larger engine option avail through the factory TC allowing early planes to use a more powerful engine with just a logbook entry, and no other testing or STC req.

Sorry.
 
I wouldn't let it be a deal breaker, it is too easy to cure the problem of missing paper work.

The FAA may have the 337s documenting this or not, if not, submit the 337s and up date the history files.

I thought of this, but my opinion is it would fall afoul of this: "Form 377 cannot be used for any changes to the airplane structure, gross weight, balance or landing gear."

Surely cutting holes in the fuselage, putting in window brackets, moving the aft bulkhead, and exposing more area to baggage loading would affect structure and balance. I hope I'm wrong, and it can be done on 337, but my review of some old Bo 337s doesn't indicate that. If it's been done once, it could prolly be done again.

<edit: I found a 337 to add a ski tube to the aft bulkhead in the early models, but that's not the same. No change in W&B, no increase in load.>
 
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Not a "deal breaker," but you will need to have it addressed and it could take some time to get it done. Like Doc said....
 
Not a "deal breaker," but you will need to have it addressed and it could take some time to get it done. Like Doc said....

Yes it will take time,,,, like 30 minutes.
 
Yes it will take time,,,, like 30 minutes.

And it seems to me like it has passed at least 5 annuals with the current owner and lord knows how many with prior owners. Why are we getting our panties in a wad over a ages-only mod that doesn't show up in the CURRENT logs. A '50s airplane should have something on the order of 3 or 4 logbooks, and looking at the current one tells you nothing.

Like Tom said, about half an hour's paperwork at most, nothing to wrinkle your whities over.

.
 
No deal breaker if the price is right,and aircraft was well maintained. Check with your mechanic and do the paperwork. Good luck
 
Yes it will take time,,,, like 30 minutes.
Maybe, maybe not. If you are going to be submitting the paperwork saying its been done, then you should at least know its done per whatever instructions that given with it originally. Maybe its quick, maybe its hard... could go either way.

And it seems to me like it has passed at least 5 annuals with the current owner and lord knows how many with prior owners. .
Well we all know that means that everything is the way it should be :rolleyes2:
Why are we getting our panties in a wad over a ages-only mod that doesn't show up in the CURRENT logs. A '50s airplane should have something on the order of 3 or 4 logbooks, and looking at the current one tells you nothing..
Op said they looked through the books extensively. Not just the current one.


No deal breaker if the price is right,and aircraft was well maintained. Check with your mechanic and do the paperwork. Good luck
:thumbsup:
 
And it seems to me like it has passed at least 5 annuals with the current owner and lord knows how many with prior owners. Why are we getting our panties in a wad over a ages-only mod that doesn't show up in the CURRENT logs. A '50s airplane should have something on the order of 3 or 4 logbooks, and looking at the current one tells you nothing.

Like Tom said, about half an hour's paperwork at most, nothing to wrinkle your whities over.

.

Because no one of the prev inspectors knew WTF they were looking for. This is a model and year specific design.

IIRC(don't guarantee on this), the Deb never was offered with the long third window and ext baggage area. So - a good IA would have seen the straight tail, the long window and said "ruh-roh, modified". But, they got away with it, and no one was the wiser. Doesn't mean it'll pass muster with a 337, or 'home-brewed' mod. Maybe will, maybe not.
 
Yes it will take time,,,, like 30 minutes.



Your conformity inspection ammounts to:

#1 Sharpening a pencil
#2 Signing papers
#3 Collecting $
---------END--------
 
Your conformity inspection ammounts to:

#1 Sharpening a pencil
#2 Signing papers
#3 Collecting $

Actually, that's my IA. Case of Buds and he would sign off a Jabaru engine installed in a DHC Beaver. :lol:
 
Well we all know that means that everything is the way it should be :rolleyes2:

Yes, because I have never come across a plane with something as major as the wrong propeller having been passed by IAs longer than I had then been alive...
 
Yes, because I have never come across a plane with something as major as the wrong propeller having been passed by IAs longer than I had then been alive...

Or the other way around. I had an insp on a bonanza before I bought it and the A&P squawked the prop as needing a bladder diaphram every 2 years or 100 hours. Problem was, he got the hub wrong, and the plane had the small hub with no bladder. I could tell from the size of the spinner which it was, and he couldn't. DOH!
 
I wouldn't pay a premium for the plane but if it is clean and near exactly what I want for a fair price I would not let this paperwork issue slow me down. I believe even if you cannot get the paper work straightened out easily you can find plenty of IA's that won't notice or pretend not to notice.


Even a Cherokee can have a 3rd window STC installed.... I have seen people paint the 3rd window black so it appears to be a newer model a/c.
 
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Maybe, maybe not. If you are going to be submitting the paperwork saying its been done, then you should at least know its done per whatever instructions that given with it originally. Maybe its quick, maybe its hard... could go either way.

Retro fitting paper work on old modifications is the easiest thing about being an A&P-IA.

For the ones that know how anyway.
 
I'm guessin it's a Beech Bonanza from the 50s. He either went with the factory later model window, or he got one of the STCs. Frankly, I would have the work inspected carefully, and if it seems ok it wouldn't break the deal.

You have little to no fear from the ramp check perspective, but from the annual perspective, this could be a real big deal. The IA that needs to inspect the plane has to account for a non-standard window and baggage panel. Most of them are not well versed enough in the model designation to know when the larger bag bay and third window were put in place. This is why the plane has been going through annual after annual without it being squawked. Technically, a smart IA would catch this, and without the STC paperwork it would have to be all undone, or you could try to source the STC from the vendor if they are still in business and have it inspected against the STC docs. If you are lucky, when you get the CD from the FAA, it'll be on there, and you can just recreated the STC. If it's not in the logs, it won't have the STC, and someone just fudged it from a later model plane. The bulkheads are all there, and the window frame and stuff is pretty easy to do as well.
This covers the situation very well, and is why making it compliant at seller's expense would be a condition of purchase for me. Note that you won't know until someone digs into it what it's going to cost to do that, it would have to be done before the sale closes.
 
And it seems to me like it has passed at least 5 annuals with the current owner and lord knows how many with prior owners. Why are we getting our panties in a wad over a ages-only mod that doesn't show up in the CURRENT logs. A '50s airplane should have something on the order of 3 or 4 logbooks, and looking at the current one tells you nothing.

Like Tom said, about half an hour's paperwork at most, nothing to wrinkle your whities over.

.
You and Tom are assuming the only problem is lack of paperwork. There is nothing to support that assumption. Further, I suspect it will take more than 30 minutes of effort to track down and obtain the paperwork, not to mention having an IA complete and document the compliance inspection.
 
Do you charge by the word for those jobs?

Retro fitting paper work on old modifications is the easiest thing about being an A&P-IA.

For the ones that know how anyway.
 
You and Tom are assuming the only problem is lack of paperwork. There is nothing to support that assumption. Further, I suspect it will take more than 30 minutes of effort to track down and obtain the paperwork, not to mention having an IA complete and document the compliance inspection.

I am a A&P-IA so there won't be any time waisted there, and the FAA 337 form is on line in PDF format and can be filled out quickly, and when it is a simple retro fit of an STC you can have that paper in minutes, FAX machine and electronic money is your friend.

I said retro fitting the paper work is easy, I did not mention anything about the aircraft. Material condition of the aircraft is simply that, and a big issue when buying any aircraft, the missing paper work isn't.

This aircraft has flown this long with no problems?

Knowing the flight testing on the modification has been done, plus it is the duplicate of a later model of the same type certificate the 337 approval will be easy, even if it does not conform to a STC.

Simply because the FAA has already certified the structure as a later model.
 
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Maybe, maybe not. If you are going to be submitting the paperwork saying its been done, then you should at least know its done per whatever instructions that given with it originally. Maybe its quick, maybe its hard... could go either way.

If your issue is material condition, that should be known long before chasing the paper.

If it ain't worth buying, it surly isn't worth chasing the paper.
 
You need to know a) that all the required parts are on the airframe, b) that any required paperwork for the STC is there or can be recreated and c) the number of hours needed to do it all it well known.

The aircraft is not airworthy without the paperwork entry - so that needs to happen.

Adjust the price accordingly.
 
You need to know a) that all the required parts are on the airframe, b) that any required paperwork for the STC is there or can be recreated and c) the number of hours needed to do it all it well known.

The aircraft is not airworthy without the paperwork entry - so that needs to happen.

Adjust the price accordingly.

This is not an STC. It's a homologation of parts from a different newer model that was never offered on this SN airframe. Albeit, the aiframes are nearly identical, and prolly came off the same assembly line, the long window and big bag bay were never offered on the Deb, or any year model that the Deb was offered.
 
This is not an STC. It's a homologation of parts from a different newer model that was never offered on this SN airframe. Albeit, the aiframes are nearly identical, and prolly came off the same assembly line, the long window and big bag bay were never offered on the Deb, or any year model that the Deb was offered.

This will require a field approval, to get one you must have a cover letter telling the FAA inspector what you are doing.

In that letter you will explain that this has been approved on the same structure on a later model, and that you used the parts from ________, and this modification was installed by people or persons unknown and has flown XXXX number of hours / years with no problems loaded IAW the later version data.

Then in block 8 of the 337 you describe the work that was done. (Installed this IAW the SRM. Installed that part etc.)

Submit it, and this may take more than 30 minutes :)
 
This will require a field approval, to get one you must have a cover letter telling the FAA inspector what you are doing.

In that letter you will explain that this has been approved on the same structure on a later model, and that you used the parts from ________, and this modification was installed by people or persons unknown and has flown XXXX number of hours / years with no problems loaded IAW the later version data.

Then in block 8 of the 337 you describe the work that was done. (Installed this IAW the SRM. Installed that part etc.)

Submit it, and this may take more than 30 minutes :)

I hope you're right. I've never done it but I've seen early planes with later features, so I know it's been done before, but I don't know how. I think I would put something in the 337 to the effect that orig W&B from the ops manual has not been modified. I'd also do a fresh W&B and submit that with the form. The empty CG is going to move back a few inches from the typical.
 
I hope you're right. I've never done it but I've seen early planes with later features, so I know it's been done before, but I don't know how. I think I would put something in the 337 to the effect that orig W&B from the ops manual has not been modified. I'd also do a fresh W&B and submit that with the form. The empty CG is going to move back a few inches from the typical.

I was pretty brief, but yes W&B is part of the block 8 description.

and you may be required to up grade the loading data to the later version, in the AFM.

see AC43-210.
 
What paperwork? :dunno:
 
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