Parts Manufacturer Approval (PMA) is a Federal Aviation Administration (FAA) approval that allows a manufacturer to produce replacement parts for aircraft and related products. It is an alternative to the traditional design and production approval process, which typically involves the original equipment manufacturer (OEM).

To obtain a PMA, a manufacturer must demonstrate that their part is identical to the OEM part in terms of form, fit, and function, and that it meets all applicable regulatory requirements, including airworthiness standards and safety protocols. The manufacturer must also provide documentation and testing data to support their claim of equivalence.

PMA parts are often less expensive than OEM parts, which can provide cost savings for aircraft operators and maintenance organizations. However, PMA parts must still meet the same safety and quality standards as OEM parts, and are subject to ongoing surveillance and inspection by the FAA to ensure continued airworthiness.

The PMA process involves several steps, including:

1. Design and development of the replacement part
2. Testing and validation of the part
3. Submission of documentation and data to the FAA
4. Review and approval by the FAA
5. Ongoing quality control and surveillance to ensure continued compliance with regulatory requirements.

Overall, PMA provides a framework for manufacturers to produce high-quality, safe, and compliant replacement parts for aircraft and related products, while also promoting competition and innovation in the industry.