【正文】 ut would exclude any A1 designated areas. In practice, satisfactory coverage may often be achieved out to around 250 nautical miles offshore. 2022 April GMDSS Services – Lecture 1 56/93 2022 April GMDSS Services – Lecture 1 57/93 Sea Area A3 ? An area, excluding sea areas A1 and A2, within the coverage of an Inmarsat geostationary satellite in which continuous alerting is available. This area lies between about latitudes 70186。 ? If, for example, a ship sends a distress signal via an EPIRB or InmarsatC satellite terminal, any ships which might be in the vicinity will not bee aware of the distress until the shore authorities relay the distress details by directing a DSC call and/or a satellite call to all ships within a defined area. 2022 April GMDSS Services – Lecture 1 67/93 transmission and reception of shiptoship distress alerts。 ? Locating and homing signals in the GMDSS are provided by radar beacons and EPIRBs. SART beacons are intended for use onboard survival craft and enable ships and aircraft engaged in a search and rescue operation to locate survivors using 9 GHz (3cm) radar. Most EPIRBs in current manufacture also incorporate some form of locating function – a SART can be included in InmarsatE EPIRB, and the COSPASSARSAT 406 MHz EPIRBs now provide for an additional transmission on MHz, which suitably equipped ships and aircraft can use as a homing signal. 2022 April GMDSS Services – Lecture 1 76/93 s SART A SART will transmit an alert that will create a series of dots on the radar display of a Search amp。 ? This refers to the SOLAS requirement that access to VHF munication equipment must be available from the position at which the ship is normally navigated and, furthermore, that this must include operation on , the frequency reserved for intership munications relating to the Safety of Navigation. 2022 April GMDSS Services – Lecture 1 83/93 Radio Personnel Requirements operator’s certificates The provisions of the Radio Regulations define four classes of operator certificate in Article S47, namely, ? First Class RadioElectronic Certificate (includes full onboard maintenance), ? Second Class Radio Electronic Certificate (includes limited onboard maintenance), ? General Operator’s Certificate (worldwide operation, but not including maintenance), ? Restricted Operator’s Certificate (for A1 ships) 2022 April GMDSS Services – Lecture 1 84/93 operator’s requirements ? Regarding the numbers and qualifications of radio personnel required on board a ship, the following rules apply: 2022 April GMDSS Services – Lecture 1 85/93 Regulation IV/16 of the SOLAS Convention requires that: ? Every ship shall carry personnel qualified for distress and safety radiomunication purposes to the satisfaction of the administration. The personnel shall be holders of certificates specified in the Radio Regulations as appropriate, any one of whom shall be designated to have primary responsibility for radiomunications during distress incidents. 2022 April GMDSS Services – Lecture 1 86/93 Article S47 of the Radio Regulations requires that GMDSS ship radio stations: ? “ shall be controlled by an operator holding a certificate issued or recognized by the government to which the station is subject”. 2022 April GMDSS Services – Lecture 1 87/93 Article S48 of the Radio Regulations ? requires that the personnel of ship stations and ship earth stations for which a radio installation is pulsory under international agreements(1) and which use the frequencies and techniques of the GMDSS shall include at least: ? a) for stations on board ships which sail beyond the range of VHF coast stations, taking into account the provisions of SOLAS: a holder of a firstor second – class radio electronic certificate or a general operator’s certificate (GOC)。 ? ? Shorebased maintenance (