Iridium installations for GMDSS configurations
Resolution MSC.436(99) which is effective from January 1, 2020, introduces the definition of 'recognized mobile satellite service'. In the associated requirements of this chapter, the term 'Inmarsat ship earth station' has therefore been replaced by 'recognized mobile satellite service'.
With regard to the reception of maritime safety information as defined in SOLAS IV/2.1.9, SOLAS regulation IV/7 (Radio equipment – General), sub 1.5 requires the following:
“Every ship shall be provided with a radio facility for reception of maritime safety information by a recognized mobile satellite service enhanced group calling system if the ship is engaged in voyages in sea area A1, or A2 or A3 but in which an international NAVTEX service is not provided…”.
Every vessel must be able to receive Maritime Safety Information (MSI). This is possible (along the coast) by NAVTEX and outside NAVTEX range the reception of MSI is secured by a recognized mobile satellite service enhanced group calling system (EGC).
For the reception of EGC messages via a recognized mobile satellite service, the world is divided into 21 areas. The NAVAREA (Navigational Area) section is available to receive navigational warnings, including Search and Rescue (SAR) messages and for the reception of weather reports the METAREA (Meteorological Area) section is available. These areas are practically the same, but the information comes to the coordinator through different channels.
Inmarsat has the 'SafetyNET' system for EGC and this information comes on board via the Inmarsat-C installation and has the full coverage for the GMDSS A3 sea area.
Iridium has set up the 'SafetyCAST' system for the reception of Maritime Safety Information (MSI). However, the “SafetyCAST” system does not yet have worldwide coverage. On Iridium SafetyCast Implementation Status | IHO the current status of the different NAVAREAS and METAREAS can be verified.
An Iridium GMDSS system which has obtained an MED/wheelmark certificate indicating that it complies with MSC.434(98) – “Performance standards for a ship earth station for use in the GMDSS,” may, in principle be placed on board ships under the Dutch Flag.
However, as mentioned above, the functional requirement “transmitting and receiving maritime safety information” is not yet fully met.
Conclusion:
Since for not mechanically propelled sail passenger ships (COS) only one Inmarsat-C ship-earth station is required below information applies.
As far as the receipt of MSI is concerned, according to the IHO website, there are blind spots worldwide due to the implementation of the SafetyCAST system. This means that, depending on the sailing area (and outside the scope of NAVTEX), the requirements of SOLAS regulation IV/7, sub 1.5, cannot always be met for ships equipped with an Iridium GMDSS system as the recognized mobile satellite service.
Currently, the Inmarsat-C terminal, via the SafetyNET system, is the only device which meets the functional requirement “transmitting and receiving maritime safety information” for the whole GMDSS sea area A3.
In the event of installation of a type-approved Iridium terminal as the recognized mobile satellite service, the NSI can agree with this subject to the following condition being stated on the relevant certificates:
“In the event that the vessel sails in an area in which the receipt of maritime safety information, as required by SOLAS regulation IV/7.1.5, is covered by neither the Iridium installation nor an international NAVTEX service, the shipowner shall ensure that an additional type-approved Inmarsat-C device is temporarily installed on board. Subject temporary Inmarsat-C device shall be inspected / tested by a radio service company approved by the Netherlands Shipping Inspectorate prior to commencing the voyage.”
When the ship owner intends to replace the Inmarsat-C terminal by an Iridium installation under the above mentioned conditions, the ships RO shall be contacted for further instructions.
For ship types, other than ‘not mechanically propelled sail passengerships (COS)’, the RO shall be contacted when the ship owner intends to replace the Inmarsat-C terminal by an Iridium installation. The RO shall then contact the NSI for further guidance in case this is deemed necessary.