What is a PMA?
A Parts Manufacturer Approval (PMA) is an FAA approved alternate replacement part for use in the maintenance of type-certificated aircraft, engines, accessories and propellers. The approval confers combined design, production, and installation authority in one document (the supplement).
History of PMA
PMA usage goes back approximately 60 years to World War II. With a large number of surplus military aircraft available after the war, several operators emerged to take advantage of these underutilized resources. Unfortunately most of the Original Equipment Manufacturers (OEMs) who manufactured aircraft parts during the war reverted back to their normal business operations - automobiles and appliances - making spare aircraft parts very difficult to find. To support this flourishing new market, the Federal Aviation Administration introduced PMA regulations to make aircraft replacement parts more readily available.
Three PMA Certification Processes (using FAA established processes and procedures)
- Identicality with a license agreement: The OEM licenses a supplier to make the part and allows that supplier to sell directly to the aftermarket. The supplement is directly approved by the MIDO and the part becomes available for sale using the same part number as the OEM part.
- Identicality without a license agreement: In this method, a PMA company has access to the critical information (drawings, tooling etc.) to prove to the certifying regulatory authority that the company can manufacture an identical part to the OEM part, but this occurs without an agreement with the OEM.
- Test and Computation (most common method): A PMA Specialist uses required analysis and test data to prove the part is equivalent to or better than the approved original OEM part.
Remember two things: 1) Both OEM and PMA suppliers adhere to the same rules, and 2) PMA parts are considered equivalent and interchangeable by the FAA and other certifying regulatory authorities.
Benefits of Using PMA
- Significant savings over the equivalent OEM product
- Extensive availability typically in stock with 24-hour shipping (even on older aircraft platforms)
- Improved aircraft part reliability