Between 2019 and 2020 Inmarsat I-3 satellites will reach their end-of-life. All I-3 satellite services must be migrated onto the I-4 satellites in order to produce their continuity.
The migration will take place in 4 stages, as shown below: (pic.1-4).
(pic.1) Move of AORW from the 3F5 satellite (54o W) to the 4F3 satellite (98o W).
(pic.2) Move of POR from the 3F3 satellite (178o E,) to the 4F1 satellite (143.5o E).
(pic.3) Move of AORE from the 3F2 satellite (15.5o W) to the 3F5 satellite (54o W).
(pic.4) Move of IOR from the 3F1 satellite (64 o E) the AF1 satellite (25 o E).
As a result, the network configuration will include such satellites as 4F1 (APAC), 4F3 (AMER), AF1 (EMEA) and I-3 satellite 3F5 (AORE).
The Ocean Region naming will stay the same for the Inmarsat-C network. The coverage or footprint of the AORW, AORE, IOR, and POR will move to the west.
Note: the coverage area of the IOR will change, due to the non-standard footprint of the AF1 (AlphaSat) satellite.
Timetable: At least 6-weeks in advance before the dates for the changing steps, users will be confirmed and notified by Inmarsat.
(pic.5) Migration timetable (For Inmarsat C (to include Aero-C and Mini-C) services is scheduled to be executed on 16 April 2018 at 10:00 UTC.)
When moving into the coverage of another Ocean Region, terminals may switch to this region automatically. GMDSS-approved terminals will provide an alarm when this occurs and require manual intervention to switch Ocean Regions (Log in). Mobile users that reside in the area that will not be covered by the new footprint Ocean Region after migration are encouraged to switch the terminal to another region before the migration occurs.
The pictures below (pic.6-9) provide a graphical overview of the areas that will no longer be covered by the “migrating Ocean Region”.
(pic.6) The area out of AORW coverage after migration.
(pic.7) The area out of POR coverage after migration.
(pic.8) The area out of AORE coverage after migration.
(pic.9) The area out of IOR coverage after migration.
The migration will not affect seafarers receiving MSI as the Inmarsat-C and Mini-C terminals will not be affected provided the terminal is logged in to an Ocean Region. Seafarers can continue to select the NAVAREA and METAREA regions from which they want to receive MSI. Under the strict supervision of International Mobile Satellite Organization (IMSO), Inmarsat Safety Team will closely monitor the migration, ensuring the 99.9% service availability level is maintained.
(pic.10) Ocean Region footprints after the complete migration.
(pic.11) Ocean Region footprints after the complete migration (with Navareas).