If the Inmarsat-C terminal is inoperative but the vessel remains within NAVTEX coverage, which message categories should not be disabled?

The correct answer includes meteorological warnings, search and rescue information, and navigational warnings as categories that should not be disabled when the Inmarsat-C terminal is inoperative but the vessel remains within NAVTEX coverage.

These message types are vital for the safety of the vessel and its crew. Navigational warnings provide information about hazards to navigation, which is crucial for avoiding accidents and ensuring safe passage. Meteorological warnings deliver important alerts about severe weather conditions that could impact the vessel's operation, allowing for informed decision-making to ensure safety at sea. Search and rescue information is vital in emergencies, as it includes updates on distressed vessels and essential procedures that may be needed in case of an accident, enabling a quick response or re-routing if necessary.

The importance of keeping these message categories active lies in their role in ensuring safety and facilitating effective operations at sea, especially when the primary communication system (Inmarsat-C in this case) is compromised. Disabling these messages could lead to a significant safety risk by depriving the crew of essential information necessary for safe navigation and emergency preparedness.