STCs, 337s, and logbooks newbie questions

[Joachim Gruber]

Hello everyone,
I'm completely new to airplane buying. Nevertheless, I'm fully aware that pre-purchase logbook and records review is of utmost importance. This brings up a few questions I have regarding the law as it relates to missing logbook entries, STCs and 337s:

1) Is an aircraft legally airworthy if the logbooks don't contain the description of the installation of an STC, but the FAA has the corresponding 337, with reference to the STC number, on file for that aircraft? For example, an airplane has a GTN650 installed, yet there's no logbook entry describing this installation. Upon reviewing the $10 CD from the FAA you see that a 337 was filed describing the installation of the GTN650 with reference to the correct STC number (i.e. "installed as per STC... instructions and sketches".

2) Does the original STC certificate have to be physically present in the aircraft's document folders? Can it be a photocopy? Is it sufficient to have a copy of the STC (with the aircraft's serial number, etc.) on file with the FAA (on the $10 CD)? What's the procedure if an original STC gets lost or destroyed?

3) What's the accepted procedure to have a shop retroactively make a logbook entry indicating that the work was done at a prior date. For example, I contact the shop that installed the GTN650, they confirm that they indeed installed the GTN650, based on their own records. They agree to make the logbook entry. How should this be documented in the logbook, specially if the work was done several years ago?

I'm looking forward to your enlightening responses.

[N3322G]

I suggest getting in touch with Kristin Winter and hiring her. She does pre-buys and is a practicing aviation attorney. See her contact info in PATHfinder on the home page of this website under members tab

[Joachim Gruber]

Pat,
Thanks for the tip. I'm already in touch with Kristin, and she's reviewing the logs for me as I write this. However, I thought that I'm probably not the only person who's not clear on this. So, I decided to post in order for others to be able to benefit and learn as well.