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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
21-32C Control of Prepositioned Products and Articles Shipped Prior to Design Approval

This advisory circular (AC) provides the applicant with a means to control products and articles prepositioned prior to the issuance of a design approval (e.g., type certificate (TC), or supplemental type certificate (STC).

 Active AIR-600 2025-09-25
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