Modification and Replacement Parts Association

The Modification and Replacement Parts Association is the Washington, D.C.-based trade association that represents manufacturers of government-approved after market aircraft parts. These aircraft parts are often known as PMA parts, from the acronym for Parts Manufacturer Approval. The manufacture of PMA parts is regulated in the United States by the Federal Aviation Administration.

MARPA's primary focus is on representing the needs of the PMA parts community in the United States. These companies manufacture after market aircraft parts under strict FAA guidelines.

In order to obtain a PMA from the FAA, the manufacturer must demonstrate that it has

The manufacturers that meet these standards are issued Parts Manufacturer Approval (PMA) by the FAA.

Because the United States was the first nation to adopt rules permitting the manufacture of aircraft after market parts (and for many decades was the only nation with these rules), the PMA industry is primarily concentrated in the United States. Other countries have started to investigate and even adopt PMA rules. Some non-US manufacturers have started to investigate the benefits that MARPA can bring to them. In the future, MARPA's manufacturing membership may reflect a more international base.

MARPA's members include many air carriers from around the world.

MARPA has an air carrier committee that remains quite active. The committee was originally formed by MARPA Director Josh Abelson, and since then has been chaired by Cori Ferguson of Alaska Airlines (2006 - 2008), David Linebaugh of Delta Air Lines (2008 - 2011), Steve Jones of American Airlines (2011-2013), and William Barrett of American Airlines (2013–present). Air carriers engage in a complete engineering review of a PMA part before they choose to install it (despite the fact that the FAA has already approved the part). Despite this engineering review (or perhaps because of it), air carriers have been adopting PMA usage in their fleets and recognizing reliability improvements and cost savings.

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