FAR 21.301 — PMA Applicability
FAR 21.301 sets the scope of Subpart K, covering procedural requirements for issuing Parts Manufacturer Approvals (PMAs) and rules for PMA holders.
FAR 21.301 is the opening section of Subpart K of Part 21, which deals with Parts Manufacturer Approvals (PMAs). A PMA is the FAA approval that allows a company to manufacture and sell replacement and modification parts for installation on type-certificated aircraft.
This section simply tells you what the rest of the subpart will cover. Specifically, Subpart K prescribes:
- Procedural requirements for issuing PMAs (how a manufacturer applies for and obtains approval), and
- Rules governing holders of PMAs (the ongoing responsibilities once a company has been granted a PMA).
Why it matters operationally: As a pilot, you generally won't apply for a PMA, but you should understand that any non-original-equipment part installed on your aircraft must be FAA-approved, often via a PMA. When reviewing maintenance logbooks or 8130-3 tags, you'll see PMA references — knowing where these approvals come from helps you verify your aircraft is airworthy and legal to fly.