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INMARSAT have announced their  D+ network services will be retired by 30th December 2014.

It is estimated 40% of vessels above 500GRT installed with IMO, SOLAS X1.2.6 Ship Security Alert Systems operate on the D+ service as a standalone system and will be required to upgrade their SSAS transceivers by 2014. Skywave communications and Satamatics (now Honeywell) are the only manufacturers of the INMARSAT D+ transceivers.

There is an estimated 13,500 Skywave and Satamatics terminals in the field. Standalone SSAS supplied between 2002 to 2008 are most affected and owners should make provisions to upgrade. Standalone systems supplied after 2008 may be operating on the enhanced INMARSAT M2M network. Unfortunately the M2M transceivers are identical in appearance confusing owners provisioning assessment.

INMARSAT have not confirmed the longevity of the M2M network services but suggest it is aligned with the I3 constellation lifespan.

Major SSAS providers Polestar/ Purplefinder (DSAS), Transas (ShipGuard), Satamatics (Ocean Alert) and MarineTrack (SeaGuard) models incorporated a D+ transceiver and will require upgrading. Argos (CLS) – Shiploc operate on separate constellation and will not be affected. Vessel that comply with their Ship Security Alert requirements using their existing INMARSAT C terminals are not affected by this phase-out.

Owners are encouraged to check the purchase date of their standalone D+transceiver Ship Security Alert Systems and record the unique serial number of the transceivers. Both manufacturers have 12 hexidecimal serial numbers Skywave start with DCC00 and Satamatics DST00.

StratumFive intends to upgrade all existing MarineTrack clients with the new Skywave IsatDataPro (IDP) transceiver that will be included in the new SeaGuard V4 due for launch 2012.

For further advice on the terminal upgrades contact