When I came on watch on my general cargo vessel at 04:00, we were just out of the Dardanelles. At that time a bulk carrier was behind us.. The hours thereafter went uneventful. The bulk carrier was sailing on our starboard side running at 12 knots over ground and we were running at 11 knots over ground. We were at about the same course, 207 deg. Suddenly I noticed on my radar that the bulk carrier was closing fast to us. I saw that she had altered course towards us while we were still at her port side. Her new COG was 178 deg. According to the AIS data on our ECDIS the CPA was 0,18 nm with a TCPA of less then 12 minutes. There were only 2 ships around us several miles away.
I called him on channel 16, then switched to a working channel. I asked him his intention. He answered “I will keep my course and speed”. He was clearly overtaking us and thus had to act according to Rule 13. My reply was that she had to go to starboard. The answer was “OK”.
However, he took no action. When the distance was 0,5 nm, I altered my course to starboard to pass her behind her stern. The bulk carrier kept her course and didn’t react.
As I see it, this is a clear case of an officer who alters course on the waypoint without thinking about the consequences.
We sent a disidentified copy of the report to the manager of the bulk carrier. The manager followed it up with the Master, who had not been on the bridge at the time. The officer who was on watch at the time did not consider that there had been a risk of collision but was sorry if his actions were not considered safe by the vessel being overtaken. The Master has advised the officer of the importance of avoiding misunderstanding between vessels in an overtaking situation.
We note that the report gave the CPA data from AIS. We point out that data for collision avoidance obtained from ARPA radar is considered to be more reliable than that from AIS.