The aeronautical fixed service (AFS) is a telecommunication service between specified fixed points provided primarily for the safety of air navigation and for the regular, efficient and economical operation of air services.[1] ("Air service" means any scheduled air service performed by aircraft for the public transport of passengers, mail or cargo.[2]) The AFS is provided by voice and data networks, including AFTN, AMHS and CIDIN.[3]
However, any aeronautical radiocommunication between specified fixed points belongs – in accordance with article 1.20 of the International Telecommunication Union's (ITU) Radio Regulations (RR) – to the Fixed service.[4]
With advancements in technology, the Aeronautical Fixed Service has evolved to incorporate modern communication systems that enhance data exchange between air traffic control units. The integration of the Aeronautical Telecommunication Network (ATN) allows for more efficient handling of flight plans, meteorological data, and other critical messages. This system supports both voice and data communications, facilitating seamless coordination among various air traffic service providers globally[5] . Furthermore, the implementation of digital data links has improved the accuracy and reliability of aeronautical communications, which is vital for maintaining safety in increasingly congested airspace.