FAA PMA Parts Explained
Parts Manufacturer Approval (PMA) is an FAA approval, issued under 14 CFR Part 21, Subpart K, that authorizes a company other than the original type certificate holder to produce a part and to sell that part as airworthy for installation on a type-certificated aircraft.
PMA has existed since 1965. On most certificated GA aircraft today you will find a mix of original-equipment (OEM) parts and PMA parts coexisting without issue. A PMA part is not a knock-off; it is an FAA-approved part, and it is legally installable wherever the corresponding OEM part is called for.
How a PMA approval is earned
There are three approval routes under Subpart K:
- Identicality with a licensing agreement — the PMA holder has a written license from the type certificate holder and produces to the same drawings.
- Identicality without a licensing agreement — the applicant reverse-engineers the part and shows, through test and analysis, that their part is identical to the approved design.
- Test and computation — the applicant shows their design is equivalent or superior by test data rather than matching the original.
All three routes require FAA engineering approval of the design (Design Approval) and FAA approval of the production quality system (Production Approval). Only then can the holder stamp FAA-PMA on the part and attach an 8130-3 airworthiness tag.
PMA vs OEM: practical differences
- Price — PMA typically runs 30–60% below OEM for the same function.
- Availability — PMA keeps legacy parts in production after the original manufacturer has moved on. This is why PMA is so common on out-of-production Cessna, Piper, and Beechcraft models.
- Traceability — both OEM and PMA ship with an 8130-3 tag. Your logbook entry cites the part number and tag regardless of source.
- Form, fit, function — by regulatory definition, a PMA part must perform identically to the OEM part it replaces. Dimensionally and materially the two are interchangeable.
When PMA may not be what you want
- Leaseback, flight school, or Part 135 operators may have written maintenance agreements that specify OEM-only to simplify SMS documentation.
- Newly certified airframes still inside the OEM warranty window — using a PMA part in an out-of-scope way can void coverage. Read your warranty.
- Insurance — most aviation insurance does not treat PMA parts differently from OEM, but some specialty policies do. Confirm with your underwriter.
Major PMA holders you will see on AAP
Tempest (magnetos, spark plugs, filters), Superior Air Parts (cylinders, engine internals), Concorde (batteries), Champion Aerospace (ignition), Bogert (cowling hardware, avionics brackets), Rapco (vacuum pumps, brake linings), AeroPerformance (engine hardware). This is a short list — thousands of PMA holders are active.
Next step
Read the companion page on FAA-Approved Parts Categories to see how PMA fits alongside Type Design, TSO, and Standard Parts. Or search the catalog for a specific part and compare OEM and PMA pricing side by side.
