

Top: Vasia, Bottom: Birthe Theresa
Hydrodynamic forces between ships traversing the Kiel Canal should be studied, says Germany’s Federal Bureau of Maritime Casualty Investigation. The report also highlights responsibility of pilots conducting vessels whose masters do not understand German and the role of Vessel Traffic System operators.
To cut to the chase, while the Cyprus-flagged tanker Vasi was overtaking the Singapore-flagged Birthe Theresa in the relatively narrow and shallow canal, the latter suddenly picked up speed, went to port and contacted Vasi. For around seven minutes the two vessels continued stuck together until Birthe Theresa went to starboard and ran aground on the canal embankment.
Says the BSU report: “…when the overtaking manoeuvre was almost complete, i.e. the Vasi’s stern was abreast with the bow of the Birthe Theresa, the overtaken vessel developed a strong, inward turning yaw-moment, which is typical in this phase. This led to the Birthe Theresa yawing to port and heading for the overtaking Vasi.