Future Air Navigation System - Overview of FANS

Overview of FANS

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.

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).

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.

A similar product (FANS-A) was later developed by Airbus for the A340 and A330. Boeing also extended the range of aircraft supported to include the Boeing 777 and 767. Together, the two products are collectively known as FANS-1/A. The main industry standards describing the operation of the FANS-1/A products are ARINC 622 and EUROCAE ED-100/RTCA DO-258. Both the new Airbus A380 and Boeing 787 have FANS-1/A capability.

ATC Services are now provided to FANS 1/A equipped aircraft in other Oceanic airspaces, such as the North Atlantic. However, although many of FANS-1/A's known deficiencies with respect to its use in high density airspace were addressed in later versions of the product (FANS-1/A+), it has never been fully adopted for use in continental airspace. The ICAO work continued after FANS-1 was announced, and continued to develop the CNS/ATM concepts. The ICAO standard for CPDLC using the Aeronautical Telecommunications Network (ATN) is preferred for continental airspace and is currently being deployed in the core European Airspace by the EUROCONTROL Agency under the LINK2000+ Programme. Mandatory carriage of the ICAO compliant system is now the subject of an Implementing Rule (for aircraft flying above FL280) issued by the European Commission. This rule accommodates the use of FANS-1/A by long haul aircraft. All other airspace users must be ICAO compliant.

Several vendors provide ICAO ATN/CPDLC compliant products. The Airbus ICAO compliant product for the A320 family is known as FANS-B. Both Rockwell Collins and Honeywell provide ICAO compliant products for Boeing aircraft, such as the Boeing 737 and 767, and the Boeing 787 will also support ICAO ATN/CPDLC compliant communications. The main standards describing the operation of ICAO compliant products are the ICAO Technical Manual, ICAO Docs 9705 and 9896, Eurocae ED-110B/RTCA DO-280B and Eurocae ED-120/RTCA DO-290.