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United States Department of Transportation United States Department of Transportation

AC 90-117 - Data Link Communications

Document Information

Data Link Communications
Date issued
Office of Primary Responsibility

This advisory circular (AC) applies to all pilots, certificate holders, operators, and/or program managers conducting data link communication operations and to those providing data communication services on behalf of operators to meet Federal Aviation Administration (FAA) and International Civil Aviation Organization (ICAO) requirements. The AC provides guidance for data link communications eligibility and compliance using Future Air Navigation Systems (FANS) 1/A(+) and Aeronautical Telecommunications Network (ATN). It defines performance concepts, data link systems, and data link services available within the National Airspace System (NAS) and international operations. This AC addresses Automatic Dependent Surveillance – Contract (ADS-C) and Controller-Pilot Data Link Communication (CPDLC). ADS-C provides a direct connection between the aircraft automation and ground automation, to exchange status information concerning the flight including automated pilot position reports. CPDLC provides efficient digital communication without frequency congestion or misunderstandings and misinterpretations common to voice communication. CPDLC – Departure Clearance (CPDLC-DCL) service provides automated DCLs with the capability to amend clearances prior to departure. Pre-Departure Clearances (PDC) and Aircraft Communications Addressing and Reporting System (ACARS) are discussed as part of the overall data link services. Guidance is also provided for performance monitoring and problem reporting.