Entry & progression
Governing: SOLAS chapter IV (as amended by MSC.496(105)); MSN 1864 (M) Amendment 1; REG Yacht Code Part A chapter 16. See also: GMDSS Short Range Certificate (SRC).
Why the GMDSS exists
Before the GMDSS, a ship in trouble relied on being heard by another ship with a radio operator on watch. The GMDSS, phased in by SOLAS from 1992 and complete in 1999, turned that round: the system is designed so that rescue authorities ashore are alerted first, quickly and automatically, and can then coordinate ships and aircraft. It combines terrestrial radio (VHF, MF, HF) with satellite systems and beacons.
In the UK, SOLAS chapter IV is implemented through the Merchant Shipping (Radio Installations) Regulations 1998, as MSN 1864 A1 explains. Commercial yachts meet equivalent requirements through the REG Yacht Code.
The functions
The REG Yacht Code (16.1) lists what the radio installation must be able to do throughout the intended voyage:
- Ship-to-shore distress alerts by at least two separate and independent means, each using a different radio communication service.
- Receiving shore-to-ship distress alerts.
- Transmitting and receiving ship-to-ship distress alerts.
- SAR coordinating communications.
- On-scene communications.
- Signals for locating by radar (SARTs).
- Maritime safety information.
- Bridge-to-bridge communications.
Every item on a GMDSS console maps to one or more of these.
The operator
MSN 1864 A1 (section 2.2) requires radio operators on UK ships to meet STCW Section A-IV/2 and hold a suitably endorsed certificate:
- ROC: for sea area A1;
- GOC: for any sea area, A1 to A4.
The STCW competences are to transmit and receive information using GMDSS subsystems and equipment, and to provide radio services in emergencies.
The 2024 modernisation
Revised SOLAS chapter IV (resolution MSC.496(105)) entered into force on 1 January 2024. For an A1 operator the changes that matter are:
- VHF radiotelephone and SARTs moved into chapter IV;
- the separate NAVTEX, EGC and HF receivers were replaced by a general requirement for a receiver capable of receiving MSI and SAR-related information (IV/7.1.1.4);
- a VHF-EPIRB is no longer accepted in place of a satellite EPIRB for ships in sea area A1;
- satellite services are now "recognised mobile satellite services" (Inmarsat and Iridium), which redefines sea area A3.
The master's authority
MSC.1/Circ.1657 is explicit: distress alerts, distress acknowledgements and distress relays are transmitted only with the permission of the master. An ROC holder operates the equipment; the master decides.
CAUTION — Code and convention The REG Yacht Code edition consulted (2019 with corrigenda) predates the 2024 SOLAS IV revision and still lists Inmarsat C by name. Check your yacht's Radio Survey and flag instructions for what applies to her.
TIP — Learn the console Draw your yacht's GMDSS console from memory: each unit, its function, its power supply. It is the fastest way to learn it and the first thing an examiner or surveyor will test.