FAR 21.307 — PMA Quality System

FAR 21.307 sets the quality system requirement for anyone applying for or already holding a Parts Manufacturer Approval (PMA). A PMA is FAA approval to produce replacement and modification parts for installation on type-certificated aircraft.

The rule itself is short: every PMA applicant or holder must establish a quality system that meets the requirements of § 21.137. In other words, FAR 21.307 doesn't spell out the quality system details on its own — it points you to § 21.137, which is the master quality system standard for production approval holders.

Why it matters operationally:

• It ensures PMA parts going onto certificated aircraft are built to a controlled, repeatable standard.
• As a pilot, when you see a PMA part in your logbook or on a component tag, you know the manufacturer was required to operate under an FAA-accepted quality system.
• It ties PMA production into the same quality framework used for TC and PC holders, giving the FAA consistent oversight of parts that end up in the airplane you fly.