AS9120B, ISO 9001:2015, and FAA AC 0056B ACCREDITED

What Is a Parts Manufacturer Approval (PMA) ?

Parts Manufacturer Approval (PMA) is defined as the approval granted by the United States Federal Aviation Administration (FAA) to an aircraft parts manufacturer. In fact, it is illegal in the US to install replacement or modification parts on certified aircraft that lack an airworthiness release like PMA or a Supplemental Type Certificate (STC). To better understand the importance of PMA, this blog will provide a brief overview of its conditions, stipulations, and more.

Before diving into the technicalities of PMA, there are other ways of meeting compliance standards, including parts manufactured to government or industry standards, Technical Standard Order Authorization (TSO) parts, and various others. However, none of these standards are quite as unique as PMA. In fact, PMA-holding manufacturers are allowed to make replacement parts for aircraft though they are not the original manufacturer of the aircraft. This process can be compared to “after-market” parts for automobiles with the exception that aircraft part production is tightly regulated by the FAA.

When an applicant for a PMA applies for approval from the FAA, the FAA prioritizes a new application based on an internal process called Project Prioritization. Covered under Order 8110.42 revision D, this document serves as instructions for the FAA reviewing personnel. Meanwhile, an accompanying Advisory Circular (AC) 21.303-4 addresses the applicant and an 8110.42C addresses both the applicant and the reviewer.

As per the order, applications for a PMA can be made in a number of ways. First, identicality is the way in which an applicant tries to convince the FAA that a PMA part is identical to the Original Approval Holder (OAH) part. Furthermore, identicality by licensure is achieved by providing evidence to the FAA that the applicant has licensed the part data from the OAH. Typically, evidence comes in the form of an assist letter provided to the applicant by the OAH. In some cases, PMA may be granted upon prior approval of an STC.

The last way to acquire a PMA is through Test & Computation. This approach consists of one or a combination of the following methods: general analysis and comparative analysis. While general analysis compares the proposed part to the functional requirements of that part when installed, comparative analysis compares the function of the proposed part to the OAH part. Today, a combination of these two is used to obtain approval of complicated parts. Nonetheless, the cognizant regional FAA Aircraft Certification Office (ACO) determines if the applicant has proved compliance with all relevant airworthiness regulations and is entitled to design approval.

The second part of the application process consists of applying to the FAA Manufacturing Inspection Divisional Office (MIDO) for production approval. Production approval can only be granted when the FAA is satisfied with the proposed parts and meets the requirements of approved design. Additionally, a Production Approval Holder (PAH) should already have met this requirement before a PMA application is filed. More than that, PMA applications based on licensure or STC do not necessitate ACO approval and can be sent directly to the MIDO.

Electronics 3Sixty is a leading distributor of all types of PMA parts. With over 2 billion ready-to-purchase products in our inventory, customers can fulfill their operational needs with ease. Initiate the purchasing process by requesting a quote on any item that sparks your interest. You can access a quote request form via our Instant RFQ service or by clicking on any available item. When completing a form, we ask that you include expected shipping time frames, desired quantities, target prices, and more as applicable. The more information you include, the better we can tailor a solution that meets your operational requirements. You can trust in the integrity of our offerings as we operate with AS9120B, ISO 9001:2015, and FAA AC 00-56B accreditation, and adhere to a strict NO CHINA SOURCING pledge, ensuring the caliber of our stock. Get started today, and see why customers rely on Electronics 3Sixty!



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