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United States Department of Transportation United States Department of Transportation

Advisory Circulars (ACs)

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Number, title, description, or office

Advisory Circulars (ACs) search results
Number Title Status Office Date
90-91K North American Route Program

Provides guidance to users of the National Air Space System for participation in the North American Route Program (NRP).

Active AJR-1 2008-12-11
90-80C Approval of Offshore Standard Approach Procedures, Airborne Radar Approaches, and Helicopter En Route Descent Areas with Change 1

This AC provides operational approval information for operators conducting operations under Title 14 of the Code of Federal Regulations (14 CFR) parts 91, 91 subpart K (part 91K), and 135 to support issuance of operations specifications (OpSpec) or letters of authorization (LOA).

Active AFS-400 2017-12-21
90-66C Non-Towered Airport Flight Operations

This AC is related to Title 14 of the Code of Federal Regulations (14 CFR) part 1, § 1.1 (traffic pattern), and part 91, § 91.13 (Careless or Reckless Operation), § 91.113 (Right-of-Way Rules: Except Water Operations), and § 91.126 (Operating On or In the Vicinity of an Airport in Class G Airspace).

Active AFS-800 2023-06-06
90-114C Automatic Dependent Surveillance-Broadcast Operations

The intent of this AC is to facilitate operations using Automatic Dependent Surveillance-Broadcast (ADS-B) technology in compliance with Title 14 of the Code of Federal Regulations (14 CFR) §§ 91.225 and 91.227. The appendices provide guidance on additional ADS-B Out and ADS-B In operations that may be authorized by the Administrator.

Active AFS-400 2025-01-14
90-120 Operational Use of Airborne Collision Avoidance Systems

This AC provides an acceptable means, but not the only means, to address operational use of Airborne Collision Avoidance Systems (ACAS) in compliance with Title 14 of the Code of Federal Regulations (14 CFR) part 91, 121, 125, 129, and 135 requirements. Title 14 CFR uses the term Collision Avoidance System (CAS) or Traffic Alert and Collision Avoidance System (TCAS) to describe what Title 49 of the Code of Federal Regulations (49 CFR) and the international community has named ACAS.

Active AFS-400 2024-11-20