A tanker loaded with gas oil (diesel) was on passage from Rotterdam. It was approaching the South Falls Buoy about 4.5 cables from the eastern edge of the SW lane with a small vessel about 1 mile ahead on its stbd bow. A faster vessel was coming up astern and I expected him to overtake on the stbd side. However I noticed he altered course to port. The tanker called him up on the VHF suggesting he overtake on the stbd side as there was much more room, but he insisted on passing to port. He passed less than 1/2 mile off and probably entered the separation zone. The tanker actually altered course to stbd to give him more room and advised the overtaking vessel of what he was doing. The overtaking vessel did not give any real reason for overtaking on the port side and I was very surprised at his actions, needlessly passing so close to a loaded tanker. The weather was fine; wind force 4 SW. Clear vis.
This report was sent to the overtaking vessel’s operator for assessment. The Maritime Advisory Board are grateful to the operator and the officers onboard for looking into the incident and providing the following response:
“Having reviewed the reports from our vessel and the tanker there does not appear to be a conflict in the facts of the manoeuvre. Our vessel’s plan was to avoid the separation lane to the North, pass 0.5 miles off the tankers and be back on track for the Dover transit. The main issue appears to be that the tanker believes 0.5 miles was too close, yet clearly the Master and OOW both believed it was an acceptable passing distance. This view is supported by the company in the light of the second vessel ahead, the speed and manoeuvrability of own ship, the sea area they were operating in, where close passing is a fact of life, and that a plan had been prepared, explained and executed correctly.”
The Maritime Advisory Board agreed with the Company’s assessment of this incident, which provides a good example of the situational assessment recommended in the previous report resulting in a variation of accepted practice; in this case the practice of overtaking on the starboard side, under controlled conditions.