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Advisory Circulars (ACs)

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Advisory Circulars (ACs) search results
Number Title Status Office Date
21-40A Guide for Obtaining a Supplemental Type Certificate

Intended as a certification guide and checklist for obtaining a Supplemental Type Certificate (STC).

Active AIR-600 2007-09-27
21-29D Detecting and Reporting Suspected Unapproved Parts

This advisory circular (AC) provides guidance to the aviation community for detecting suspected unapproved parts (SUP) and reporting them to the Federal Aviation Administration (FAA).

Active AIR-600 2016-07-12