Future Air Navigation System

The Future Air Navigation System (FANS) is an avionics system which provides direct data link communication between the pilot and the air traffic controller. The communications include air traffic control clearances, pilot requests and position reporting. In the FANS-B equipped Airbus A320 family aircraft, an Air Traffic Services Unit (ATSU) and a VHF Data Link radio (VDR3) in the avionics rack and two data link control and display units (DCDUs) in the cockpit enable the flight crew to read and answer the controller–pilot data link communications (CPDLC) messages received from the ground.

The world's Air Traffic Control system still uses components defined in the 1940s following the 1944 meeting in Chicago which launched the creation of the International Civil Aviation Organisation (ICAO). This traditional ATC system uses analog radio systems for aircraft Communications, Navigation and Surveillance (CNS).

Air traffic control's ability to monitor aircraft was being rapidly outpaced by the growth of flight as a mode of travel. In an effort to improve aviation communication, navigation, surveillance, and air traffic management ICAO standards for a future system were created, this integrated system is known as the Future Air Navigation System (FANS) and allows controllers to play a more passive monitoring role through the use of increased automation and satellite based navigation.

In 1983, ICAO established the special committee on the Future Air Navigation System (FANS), charged with developing the operational concepts for the future of air traffic management (ATM). The FANS report was published in 1988 and laid the basis for the industry's future strategy for ATM through digital CNS using satellites and data links. Work then started on the development of the technical standards needed to realise the FANS Concept.

In the early 1990s, the Boeing company announced a first generation FANS product known as FANS-1. This was based on the early ICAO technical work for automatic dependent surveillance (ADS) and controller–pilot data link communications (CPDLC), and implemented as a software package on the flight management computer of the Boeing 747-400. It used existing satellite based ACARS communications (Inmarsat Data-2 service) and was targeted at operations in the South Pacific Oceanic region. The deployment of FANS-1 was originally justified by improving route choice and thereby reducing fuel burn.

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