A radio service in which common carriers are authorized to offer and provide radio telecommunications service for hire to subscribers in aircraft. [47CFR]

A worldwide military network of ground stations that (a) provides two-way communications links between aircraft and ground stations for navigation and control, including air route traffic control and (b) may also provide support for special functions, such as for civil aircraft providing assistance to military missions and for meeting communications requirements for aircraft flying distinguished visitors.

A coaxial cable in which air is the primary dielectric (insulator) between the inner and outer conductors.
Note: Proper separation between the inner and outer conductors is maintained by a continuous helical insulator or a series of insulating washers spaced at regular intervals.

1. Airborne equipment used to relay radio transmission from selected originating transmitters. [JP1]
2. A technique employing aircraft fitted with radio relay stations for the purpose of increasing the range, flexibility, or physical security of communications systems.

A mobile Earth station in the aeronautical mobile-satellite service located on board an aircraft. [NTIA] [RR]

An international aeronautical emergency frequency, such as
12
1. 5 MHz (civil) and
24
3. 0 MHz (military), for aircraft stations and stations concerned with safety and regulation of flight along national or international civil air routes and maritime mobile service stations authorized to communicate for safety purposes.

A mobile station in the aeronautical mobile service, other than a survival craft station, located on board an aircraft. [RR]

An aeronautical station providing communication between an airdrome control tower and aircraft. [NTIA] Synonym airport control station.

Synonym airdrome control station.

Abbreviation for: 1)alarm indication signals, 2) automated information system.