Parts Manufacturer Approval

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Parts Manufacturer Approval (PMA) is an approval granted by the United States Federal Aviation Administration (FAA) to a manufacturer of aircraft parts. [1]

Contents

[edit] Approval

It is generally illegal in the United States to manufacturer replacement or modification aircraft parts without a PMA (although there are a number of exceptions to this general rule, including parts manufactured to government or industry standards, parts manufactured under technical standard order authorization [TSOA], etc.). [2]

Thus, PMA-holding manufacturers are permitted to make replacement parts for aircraft, even though they may not have been the original manufacturer of the aircraft.

Application for a PMA is usually a two step process. First, the manufacturer-applicant must demonstrate to the FAA that it has a safe design for a part. The design must meet the requirements of the FAA's safety regulations and standards. This can be demonstrated in a number of ways. The applicant may rely on a licensing agreement with another approved manufacturer who has already obtained approval of the design in question. The applicant may use copmarative analysis to show that the parts it makes are the same (in all relevant airworthiness characteristics) as other parts that are already approved. The manufacturer may rely on qualitative analysis to show through test andf computation that the part directly meets the FAA's safety standards. The modern trend is to use a variety of techniques in combination in order to obtain approval of complicated parts - relying on the techniques that are most accurate and best able to provide the proof of airworthiness desired.

The second step in the application process is to seek FAA approval of the manufacturing quality assurance system (known as production approval). Production approval will be granted when the FAA is satisfied that the system will not permit parts to leave the system until the parts have been verified to meet the requirements of the approved design.

[edit] History

The aircraft parts aftermarket expanded greatly in the 1980s as airlines sought to reduce the costs of spares by finding alternative sources of parts. During this time period, though, many manufacturers failed to obtain PMA approvals from the FAA.

In the 1990s, the FAA engaged in an "Enhanced Enforcement" program that educated the industry about the importance of approval and as a consequence a huge number of parts were approved through formal FAA mechanisms.[3] Under this program, companies that had previously manufactured aircraft parts without PMAs could apply for PMAs in order to bring their manufacturing operations into full compliance with the regulations. This movement brought an explosion of PMA parts to the marketplace.

[edit] Industry reaction

Some large manufacturers of engines and airframes have seen the PMA movement as a threat. PMA manufacturers represent competition and that competition has at times undercut efforts by some manufacturers to engage in monopolistic pricing schemes. The political landscape has been changing in recent years, though, as PMA parts have become more and more accepted, and as their safety record has continued to be seen as excellent. The economic advantages of PMA parts have caused some large manufacturers to rethink their positions and to begin forming strategic partnerships and alliances with PMA manufacturers. At least one large engine manufacturer (Pratt & Whitney) has begin to seek its own PMAs on a a competitor's engine (the CFM56-3 engine from CFMI).[4] [5]

[edit] The future

The FAA is currently working on a significant revision to the manufacturing regulations. The proposed rule has been released to the public for comment and a final rule is expected in Late 2008 or 2009. This new rule is expected to eliminate some fo the legal distinctions between forms of production approval issued by the FAA, which should have the effect of further demonstrating the FAA's support of the quality systems implemented by PMA manufacturers.

[edit] Relationship to repair

The FAA is also working on new policies concerning parts fabricated in the course of repair. This practice has historically been confused with PMA manufacturing, although the two are actually quite different practices supported by different FAA regulations. Today, FAA Advisory Circular 43.18 provides guidance for the fabrication of parts to be consumed purely during a maintenance operation, and additional guidance is expected to be released in the near future. One of the key features of AFC 43.18 is that it recommends implementation of a quality assurance system quite similar to the fabrication inspection systems that PMA manufacturers are required to have.

[edit] Industry association

The trade association representing the PMA industry is the Modification and Replacement Parts Association (MARPA). MARPA works closely with the FAA[6] [7] and other agencies to promote PMA safety. MARPA maintains a website at http://www.pmamarpa.com.

[edit] External LInks

[edit] Notes

  1. ^ 14 C.F.R. 21.303 PMA
  2. ^ 14 CFR 21.303(b) 14 CFR 21.303(b)
  3. ^ 60 Fed. Reg. 10480 (February 27, 1995)
  4. ^ See Pratt & Whitney Press Release Dated March 18, 2008 concerning initial STC design approval for for CFM56-3 parts destined to be produced under PMA
  5. ^ See Pratt & Whitney Press Release Dated May 14, 2008 concerning subsequent STC design approval for CFM56-3 parts destined to be produced under PMA
  6. ^ Agenda for the 2008 FAA-EASA International Safety Conference, in which MARPA's President (Jason Dickstein) is speaking on collaborative efforts to improve supplier control
  7. ^ 70 Fed. Reg. 65713 (November 9, 2006)(FAA acknowledges the assistance of Jack Buster, MARPA Airworthiness Directive Committee)