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United States Department of Transportation United States Department of Transportation

AC 90-120 - Operational Use of Airborne Collision Avoidance Systems

Document Information

Number
90-120
Title
Operational Use of Airborne Collision Avoidance Systems
Status
Active
Date issued
2024-11-20
Office of Primary Responsibility
AFS-400
Description

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. Other traffic awareness systems, such as Automatic Dependent Surveillance-Broadcast (ADS-B) Traffic Advisory System (ATAS), are not covered in this AC. CAS for unmanned aircraft, including Remain Well Clear (RWC) and Detect and Avoid (DAA) systems, are not covered in this AC.

Content
Cancels
Cancels
Number Title Date
120-55C Air Carrier Operational Approval and Use of TCAS II

 This advisory circular (AC) provides an acceptable, but not the only, means to address Traffic Alert and Collision Avoidance System (TCAS) issues related to installation and use of TCAS II regarding compliance with Title 14 of the Code of Federal Regulations (14 CFR) parts 121, 125, and 129 requirements for air carriers.

 2011-02-23