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October 12, 2005

AIS data problems

Many vessels are transmitting AIS (Automatic Identification System) messages with incomplete or incorrect data.

The situation has been discovered in monitoring of AIS messages by the International Association of Marine Aids to Navigation and Lighthouse Authorities (IALA AISM).

According to a Marine Circular issued yesterday by the Maritime and Port Authority of Singapore the causes seem to be mostly:

(a) Incorrect setting of static data, such as the MMSI number and the vessels' dimensions, during the initial installation of the AIS on board;

(b) Omission of updating the voyage related data, such as the destination, estimated time of arrival (ETA) and changes in navigational status, by the crew;

(c) Incorrect input or processing of dynamic data, such as the position, course, speed and heading, from the vessels' sensors; and

(d) Inconsistent naming of some data, such as the vessels' name and destination.

The circular advises shipmasters and navigating officers to check that their vessels' AIS are transmitting complete and correct data.