FAA Form 337 Validity

by Brian Larivee
(Hawker Beechcraft Services-Houston)

An aircraft had several STC's installed by US repair stations and 337 forms completed while it was foreign registered (in Mexico).


It was then imported into the US and given a Standard C of A in 2003. The 337 forms in the records for these STC's have the registered owner and the Mexican registration listed.

I am being told that the 337 forms are invalid with the Mexican registration number.

How do I correct this without doing a conformity inspection and issuing new 337's now 8 years later?


ANSWER: Even though the FAA Form 337’s were issued while the aircraft was under the Mexican registry, they are still valid records of the work performed, and form part of the historical records for the aircraft.

I am sure the serial number of the aircraft is also listed on the 337 and that ties the work to the specific aircraft regardless what the registration is.

The use of the form is only required for U.S. registered aircraft, but it is not uncommon for repair stations to use this document as a record of work performed on a foreign registered aircraft. It is just not sent to the FAA to be placed in their archives.

So, there is no action required other then to keep those records on file to document the alterations that were performed. You should also have a complete data package for each STC as outlined on the Master Drawling List (MDL) or other top document listed in the body of the STC, as well as a permission letter from the STC holder to use the STC.

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