Goals, Operators, Methods, Selection (rules) A family of tools and techniques based on theory of the human information processor. The acronym refers to the basic components of the analysis: Goals, Operators, Methods and Selection rules. GOMS techniques are particularly useful in cases where the sequence of events is known.
Gross Navigational Error A gross navigational error is defined as a deviation from cleared track of 25 nautical miles or more, and these errors are normally detected by means of long range radars as aircraft leave oceanic airspace.
Ground Data Circuit Terminating Equipment A ground specific data circuit-terminating equipment associated with a ground data link processor (GDLP). It operates a protocol unique to Mode S data link for data transfer between air and ground
Ground Data Link Processor A ground-resident processor that is specific to a particular air-ground data link (e.g. Mode S), and which provides channel management, and segments and/or reassembles messages for transfer. It is connected on one side (by means of its DCE) to ground elements common to all data link systems, and on the other side to the air-ground link itself.
Ground Earth Station The GES is a fixed radio station capable of communicating with aircraft via satellite. They consist of a dish antenna, and access, control, and signalling equipment. A GES is the ground link or interface between the satellite system and the international telecommunications network. Thirteen GESs are now in operation serving suitably equipped aircraft world-wide. Both voice and data services are available from all GESs. These GESs provide at lust dual redundant coverage in all ocean regions. Other countries may elect to install aeronautical GESs in the future.
Ground Initiated Comm-B Protocol (Mode S) A procedure initiated by a Mode S interrogator for eliciting a single Comm-B segment from a Mode S aircraft installation, incorporating the contents of one of the 255 Comm-B registers within the Mode S transponder.