The GMDSS system is made up of five sub-systems as follows: DSC (digital selective calling) terrestrial communications system. Dedicated frequencies are made available for maritime communications operating in the VHF, HF and MF radio bands. This provides long, medium and short-range communications. Use is made of DSC technology which provides a means of calling a…
Radio watchkeeping is automatic with GMDSS. When receiving equipment is activated an operator is alerted. After this, further distress and safety communications are carried out on radio telephone or radio telegraphy (Narrow Band Direct Printing). It should be noted that the previous (specialist) telecommunications officer is now only carried aboard passenger vessels. On all other…
World-wide coverage is achieved by a combination of satellite and terrestrial systems. The areas are defined according to the coverage of VHF, MF and HF coast stations and Inmarsat services. The area of operations of a vessel determines the type of communications equipment it shall carry.
The areas are defined as follows: Sea area A1. The sea area within radio telephone coverage of at least one coastal VHF station in which continuous digital selective calling (DSC) alerting is available. Basically this area extends up to 50 nautical miles from the coastal station. Sea area A2. This is the sea area, excluding…
In the past distress and safety relied primarily on the ship in distress alerting another ship for assistance. Now, emphasis is placed on the ability of a vessel to alert SAR authorities ashore as well as shipping in the vicinity to ensure a coordinated response. Shore based authorities now have the primary role of coordinating…
Old system. In grade 11 you learnt about the previous maritime distress and safety system which applied to all vessels upon the high seas. According to the system: all passenger vessels and cargo vessels of 1600 gross tons and above had to maintain a continuous radio telegraphy (morse) watch on 500 kHz; and all passenger…
The Meteorology syllabus was covered in Grades 10 and 11 so won’t be dealt with here. Please refer to those sections on this website for revision.
The following certificates must be carried by merchant ships: Certificate of Registration. International Tonnage Certificate (this gives the gross and net tonnage). Passenger and Safety Certificate (if a ship carries more than 12 passengers). This gives the number of passengers the ship is registered to carry and also covers the safety aspects such as life…
All ships are required to keep a deck and engine room log in order to keep a record of activities during a voyage. The Deck log is kept by the officers of the watch and usually includes the following information: Courses steered. Compass errors. Engine movements. Daily distances covered. Time of passing important headlands. Positions…
The maximum depth to which vessels are allowed to load at different seasons and in different parts of the world are laid down in Schedule 2 of the Loadline Rules (1968). An official chart has been drawn up, showing the sea areas of the world divided up into zones and areas in such a way…
