The FAA recently stopped short of chiding OEMs for threatening to invalidate warranties if FAA-approved PMA (parts manufacturing approval) parts are used in place of OEM parts, but the agency did underscore the legality and interchangeability of such parts.
The August 8 Special Airworthiness Information Bulletin (SAIB) NE-08-40 titled “Powerplant–Original Type and Production Certificate Holder Parts and Aftermarket Modification and Replacement Parts” states, “In today’s competitive market, owners and operators are continuously searching for ways to reduce costs while maintaining safety. One way is to reduce maintenance expenses by finding alternative sources of replacement parts.”
The SAIB goes on to say, “PMA and STC (supplemental type certificate) parts are thoroughly evaluated for compliance with respect to any changes they introduce and their effect on the original type design. The need for supplemental ICAs (instructions for continued airworthiness), new airworthiness limitations and other conditions is established by the FAA to ensure the safe integration of the PMA and STC parts into the product.”
While some OEMs attempt to monopolize the parts market by edict of warranty, the SAIB clearly states that an approved PMA part is functionally as good as the original. However, since an SAIB is a recommendation rather than a requirement, the disagreement between OEMs and PMA providers is likely not over.