Comaparative study of the accuracy of AIS and ARPA indications. Part 2. Accuracy of the opposite vessel true course and true speed indication

The article presents analysis of the automatic radar plotting aid (ARPA) and automatic identification system (AIS) indications reliability performed on the base of the results of measurements conducted on merchant vessels at sea. In the first part of the article titled “Comparative study of the accuracy of AIS and ARPA indications. Part 1. Accuracy of the CPA indications” are described: vessels on which the tests were carried out, AIS and radar equipment installed on them, observed meeting situations and accuracy of the CPA indication. In this article are discussed, for the same meeting situations, accuracy of the information on true course and true speed of the opposite vessel presented by ARPA and AIS and correlation between this accuracies and errors of the CPA indication.