92001 Near Miss Overtaking, Nav by Radar

Visual lookout versus Radar watch - Night time, good visibility. Overtaking vessel in Traffic Separation Scheme. - Report No. 92001.

---

This was an observed near miss from the reporters own vessel. Vessel A was being overtaken by vessel B in a traffic separation zone, close to the alter course position. Vessel A was making 11 knots, vessel B 14 knots. Vessel A reached its alter course position slightly before vessel B had reached its alter course position.

Vessel A then altered its course from 0000 to 0410. Almost immediately afterwards vessel B altered in a similar manner. The time lag in the alteration of course by both vessels reduced the distance between them.

Vessel A then called up vessel B on the VHF, and asked B to keep clear as the overtaking vessel. Vessel B replied that there was no risk, as vessel B was on 0410, and from his radar he could see that vessel A was on 0000 .

Vessel A replied that he was not on 0000 but on 0410 and required vessel B to keep out of the way as the overtaking vessel. Vessel B then reluctantly altered more to starboard to increase the distance between the two vessels.

The conclusions from this are that vessel B was using radar, possibly ARPA, and not keeping a visual watch. The officer was placing all his trust in the radar information when he could have looked out of the window and seen the situation easily. There should have been no reason for vessel A to resort to VHF contact to avoid collision.