Subelement F: Maritime Safety Information (M.S.I.)— Topic :
Question 42F4
Element 7R (GMDSS-RO)What system may be useful for messages, such as local storm warnings or a shore-to-ship Distress alert, for which it is inappropriate to alert all ships in the satellite coverage area?
Explanation
Enhanced Group Call (EGC) is an Inmarsat satellite service that allows messages to be sent to *selected* groups of ships or to ships within a *defined geographic area*. This capability is crucial for delivering localized information, such as specific storm warnings or a distress alert to a particular vessel, without alerting all ships throughout the vast satellite coverage area. This selective targeting prevents unnecessary alerts to vessels not relevant to the warning or incident.
NAVTEX is a terrestrial (MF/HF) broadcast system for navigational and meteorological warnings, not a satellite service. AMVER is a voluntary reporting system used to locate vessels for rescue coordination, not a messaging service. Digital Selective Calling (DSC) is used for direct digital calls between stations or general distress alerts, but EGC provides the specific *area-based* satellite broadcast capability described.
Related Questions
42F2 What is the purpose of the dedicated EGC receiver for A-1 area GMDSS Vessels?42F3 Which of the following provides a unique automated system capable of addressing messages to predetermined groups of ships or all vessels in both fixed and variable geographic areas?42F5 What services are available through Enhanced Group Calls?42F6 What messages originate from registered information providers anywhere in the world and are broadcast to the appropriate ocean region via a LES?43G1 Adjusting the volume control has the following results: