Aircraft Maintenance

PMA parts are now accepted at the purchasing and quality assurance levels within air carriers because they have conducted investigations. “Air carriers had to investigate them to figure out whether or not they represented a good economic value,” says Dickstein. “When they did that investigation they found that, not only were they a good economic value, but they’re safe.”

Eligible components
According to a draft of FAA Order 8120.2F, “Manufacturing inspection procedures, materials, and/or special processes, such as hardening, plating, or shot-peening are not in and of themselves eligible for PMA.”

A PMA may be obtained for replacement parts for TSO articles that are approved as part of a product type design, provided that installation eligibility to that product can be shown. Approval of a part that would constitute a major design change to the TSO article cannot be done under a PMA and would require a new TSO authorization.

Even critical components can be PMAed in compliance with specific FAA guidance. “In fact, not only can you get a PMA on a critical part, but when you see a PMA on a critical part, chances are that critical part has gone through a level of FAA scrutiny that the OEM part didn’t go through,” says Dickstein.

Manufacturers usually have many designated engineering representatives (DERs) on staff to approve their data. “For critical components, the use of DERs is often times limited or potentially unavailable to the PMA house,” says Dickstein. “Since critical parts are, well, critical, and because of the press and public relations associated with critical parts, the FAA has decided that they’re going to keep a tighter rein on those parts. It can take a lot longer to work those through the FAA. DERs may be less available or unavailable to those applications because of the fact that the FAA is retaining more of the oversight.”

The FAA has to witness all trials of the most critical components. These will never be delegated to a DER. The FAA has to do its own analysis of all the data and make the individual regulatory compliance findings themselves.

The draft for FAA Order 8120.2F also states that once a PMA part has left a PMA holder’s quality system, the holder must establish a procedure to report any failure, malfunction, or defect of the part to the FAA.