Murphy’s Law is more consistent than the Law of Gravity: If something can go wrong it will, and at the most critical moment. An unresolved engine problem, a contined waterway and an overtaking maneouvre bought together the 12,878 dwt Antigua and Barbuda-flagged CMV Conmar Avenue with the 88,669 dwt Netherlands-flagged Maersk Kalmar on the Outer Weser between fairway buoys 29 and 31 in the Fedderwarder Fairway, Germany.
The joint accident report from Germany’s BSU and Antigua and Barbuda’s Inspection nd Investigation Division, emerges a few weeks after video of what appears to be a somewhat similar siuation in the Suez Canal circulated on the internet. That partiular incident remains under investigation.
Earlier in the day CMV Conmar Avenue had problems with the supply of lubricating oil to the main engine. Despite appropriat efforts the problems were not resolved by the time the vessel attempted to over take Maersk Kalmar. During the overtaking maneouvre CMV Conmar Avenue’s engines shut down, a safety measure intended protect the engine from damage.
As CMV Conmar Avenue lost speed hydrodynamic interaction, often freferred to as Bnk Effect, pulled her into the much larger Maersk Kalmar. Her forecastle rammed into the starboard side of the larger vessel’s aft section at an angle of about 60 degrees. The force of the collision caused 15 containers on the CMV Conmar Avenue to fall overboard.
Both ships sustained material damage above the waterline. The accident did not result in any injuries and there was no pollution of any significance. The fairway had to be temporarily closed to transiting shipping.
Due to the ebb current and her loss of manoeuvrability, the CMV Conmar Avenue ran aground outside the fairway level with buoy 30 after the collision. She anchored there and was pulled back into the fairway with the help of five tugs.
In other similar cases investigated says the BSU: “While the suction effect could not be contained effectively by the smaller vessels despite the availability of rudder and engine and as such it was the passing distance
that warranted questioning in the aforementioned accidents, the CMV Conmar Avenue had initially chosen an adequate passing distance. The CMV Conmar Avenue‘s involuntary and uncontrollable approach to the Maersk Kalmar due to the suction effect, which ultimately led to the accident, was caused by nothing other than the loss of propulsion and ensuing loss of the ability to steer.”
While the phenomenon of hydrodynamic interaction is well known, given the present state of knowledge it remains impossible to compute or predict n a way that is usable onboard.
Unfortunately, the VDR data on the CMV Conmar Avenue was not backed up, either because the backup button had not been pressed for long enough or it was pressed too long. This means that important data concerning decisions made on the bridge, whether the prolems with the lubricating oil were fully know or appreciated on the bridge is not availble.
That uncertainly means the BSU is dispensing with the publication of specific safety recommendations. Nevertheless, the publication of this summary investigation report aims to raise the awareness of officers in charge of the navigational watch and officers in charge of the engineering watch, as well as shore-based inspectorates of the urgent need to investigate technical faults immediately when they occur. If fault finding is inconclusive, then it is necessary to take precautionary measures for the event that the fault recurs.