Allision due to failure to account for tidal stream
The UK Marine Accident Investigation Branch (MAIB) released the summary of its preliminary examination into the allision of a bulk carrier with an anchored bulk carrier off Port Talbot on 13 August 2010. The vessel was departing the offshore anchorage in preparation for a port entry. While making a substantial turn, the tidal stream set the bulker down onto the anchored ship. Examination revealed that the strength of the tidal stream (three knots) had not been identified in the passage plan.
Source: MAIB