Aeronautical mobile service

Aeronautical mobile service (short: AMS; also aeronautical mobile radiocommunication service) is a form of aviation communication conducted through radio. The ITU Radio Regulations divide AMS into communication used for civil air route flights (R) and off-route flights (OR). Aeronautical mobile (R) service is a so-called safety-of-life service, must be protected for interferences, and is an essential part of air traffic control. Communication occurs between radio stations onboard aircraft, termed aircraft stations, and terrestrial stations that are sometimes termed "aeronautical stations". Communication can also occur between aircraft.^[1] AMS is commonly used in air traffic control.

Aeronautical station of the Aeronautical mobile (R) service near Hannover, Germany

Aeronautical station of the Aeronautical mobile (OR) service in Afghanistan

Aeronautical mobile (R) service in the Washington ARTCC

US Airways Flight 1549 record (ATC) during the emergency landing in the Hudson River

Britische VOLMET-record on HF

Aeronautical mobile satellite service

Principle of aeronautical mobile satellite service

Aeronautical mobile satellite service (AMSS) is a form of AMS where an aircraft station is connected to a communications satellite. It is useful in situations where the aircraft is far away from any radio station on land.^[2]

Frequency allocation

The allocation of radio frequencies is provided according to Article 5 of the ITU Radio Regulations (edition 2012).^[3]

In order to improve harmonisation in spectrum utilisation, the majority of service-allocations stipulated in this document were incorporated in national Tables of Frequency Allocations and Utilisations which is within the responsibility of the appropriate national administration. The allocation might be primary, secondary, exclusive, and shared.

• primary allocation: is indicated by writing in capital letters (see example below)
• secondary allocation: is indicated by small letters
• exclusive or shared utilization: is within the responsibility of administrations

However, military usage, in bands where there is civil usage, will be in accordance with the ITU Radio Regulations. In NATO countries military utilizations will be in accordance with the NATO Joint Civil/Military Frequency Agreement (NJFA).

Example of frequency allocation

Allocation to services
Region 1	Region 2	Region 3
2 850–3 155 MHz AERONAUTICAL MOBILE (R)
3 025–3 025 AERONAUTICAL MOBILE (OR)

Frequency range (shortwave)

On-Route (R)				Off-Route (OR)
2850	–	3025 kHz		3025	–	3155 kHz
3400	–	3500 kHz		3500	–	3950 kHz
4650	–	4700 kHz		4700	–	4850 kHz
5450	–	5480 kHz		5450	–	5480 kHz
5480	–	5680 kHz		5480	–	5730 kHz
6525	–	6685 kHz		6685	–	6765 kHz
8815	–	8965 kHz		8965	–	9040 kHz
10005	–	10100 kHz		11175	–	11275 kHz
11275	–	11400 kHz		13200	–	13260 kHz
13260	–	13360 kHz		15010	–	15100 kHz
17900	–	17970 kHz		17970	–	18030 kHz
21924	–	22000 kHz		23200	–	23350 kHz

See also

• Radio station
• Radiocommunication service