Log Books and removed STCs

[thito01]

Along with my normal logs, I have a folder of all the 337's and STCs ever installed on my aircraft. Some have since been removed, but the 337's and STC paperwork still exists in the folder.
Is there any point in keeping those STC documents as some of them are bulky?
(IIMorrow Loran, DME, Stand-by Vac, MAC radio)
Tony T.

 

[Domenick]

Personally, I would keep them. It shows a complete history of the plane, instilling confidence in a potential buyer that the owners were truthful and conscientious.

It may also explain any remnants they find during pre-buy inspection and after sale.

 

[Bell206]

Is there any point in keeping those STC documents

Part 91.417 directs you to what documentation you need to retain, transfer at sale, or discard. 337s and STC docs of those major alterations still installed need to be retained and transferred at the time of aircraft sale.

Some have since been removed, but the 337's and STC paperwork still exists in the folder.

There’s no one answer to this. There is guidance on how to legally remove/document the previously installed major alteration. If you still have the documentation for a previous major alteration that was not removed per that guidance you may want to hold onto those documents until you can correct that issue. Whether that correction will require a new 337 depends on several factors. Best to discuss with your APIA and get his input as it can create conformity issues with his annual sign-off that he is not aware of.

 

[Salty]

Is there a legitimate scenario where an Stc could be removed without a 337? I wouldn’t worry if there was one in the past, but I’m curious if, done correctly, that could ever be the case.

 

[Bell206]

Is there a legitimate scenario where an Stc could be removed without a 337?

Yes. If the STC has removal/restoration instructions included in the data package no 337 is required. Same for a field approval 337 as well if those removal instructions are included in the FA ICAs.