Study Reliability of the Information About the CPA and TCPA Indicated by the Ship's AIS

According to the International Maritime Organization (IMO) recommendation when the target data from automatic identification system (AIS) and radar tracking are both available and the association criteria are fulfilled such that the AIS and radar information are considered as for one physical target, then as a default condition in radar equipment, the AIS target symbol and the alphanumerical AIS target data should be automatically selected and displayed only. The article presents research conducted in real conditions on the reliability of information presented by the ship's AIS about the passing distance with the other vessel equipped with AIS and time to pass it by comparing data from the AIS with that presented by ARPA.