Comparative Study of the Accuracy of AIS and ARPA Indications. Part 1. Accuracy of the CPA Indications

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