Where can I find more information about an aircraft’s history? For example, past repairs, modifications, any Form 337 records, past owners, etc.?
Anyone purchasing an aircraft should make sure that the aircraft’s actual “configuration” really is “legal”, particularly when it is obviously “non-stock”. This should be a part of the pre-purchase inspection. A comparison to the Type Certificate (A1CE, available here on the BAC site) can be made for the major items. It has actually happened that someone bought a plane with a non-original engine or propeller (for example), only to later discover that the change was never officially approved. Just because there is a 337 form with the aircraft’s records, and entries in the log book, does not mean that the form was properly approved by, and filed with, the FAA.
Many changes may be approved by the A&P-IA who signs and submits the form, in which case it is just a matter of time (possibly years, believe it or not), before it finally shows up in the FAA records database. But unless it is an STC’d change, something major like an engine or prop change usually requires an advance FAA “field approval”. The A&P-IA is supposed to document the intended work, along with the “approved data” that substantiates the changes, on the Form 337. The form (usually with attached data) then goes to the FAA. With some luck, and usually following a lot of “give and take”, some day the FAA will return it as an approved change (usually a “one-time” change applicable to only that specific serial number airframe). At that point it is “safe” to ground the airplane and make the change. Then the A&P-IA signs the 337 to return the plane to service, and (again) sends the completed package to the FAA for file. This process can take a very long time, even when the work itself seems pretty simple. Note that changes that are based on existing Type Certificate data for the involved airframe, which will use factory parts, usually do not require an advance field approval. They may not even require a Form 337 if they are “minor changes”; a log book entry may be sufficient. Like so many other FAA regulations, interpretations often
Until the finished forms make it into the aircraft’s records in the FAA, the aircraft’s official status is up in the air. It is critical that a signed copy of both kinds of 337s (those that did and did not require the FAA Field Approval) remains with the aircraft’s “local records”. That is the only defense against submitted records being lost by the FAA (which happened during some past FSDO closures), and having the local records is what makes the plane legal to fly (provided they are completed and approved as required for the type of change).
There are several sources for the official FAA records. You can now obtain them directly from the FAA on a CD for only $5. While the official wait is something like three to four weeks, in my experience it has taken less than half that long. Getting certified paper copies from the FAA costs much more and takes much longer. the FAA site is:
www.faa.gov, more directly at http://162.58.35.241/e.gov/ND/airrecordsND.asp
You can order records copies from AOPA for $99, and receive the results within 24 hours, if you are in a big hurry. There are some other records retrieval services as well, but I have not tried them out. Here is the AOPA link:
http://www.aopa.org/info/certified/tne/TitleSearch.htm