Bourbon Dolphin Investigation Results

[tengineer]

This may be of interest to some of the anchor boat folks on the forum. It brings up some interesting points.

"Key conclusions are:

• The vessel was built and equipped as an all-round vessel AHSV (Anchor Handling Supply Vessel). Uniting these functions poses special challenges.
In addition to bollard pull, anchor-handling demands thruster capacity, powerful winches, big drums and equipment for handling chain. Supply and cargo operations demand the biggest possible, and also flexible, cargo capacities both on deck and in tanks. The “Bourbon Dolphin” was a relatively small and compact vessel, in which all these requirements were to be united.

• The company had no previous experience with the A 102 design and ought therefore to have undertaken more critical assessments of the vessel’s
characteristics, equipment and not least operational limitations, both during her construction and during her subsequent operations under various conditions. The company did not pick up on the fact that the vessel had experienced an unexpected stability-critical incident about two months after delivery.

• The vessel’s stability-related challenges were not clearly communicated from shipyard to company and onwards to those who were to operate the vessel.

• Under given load conditions the vessel did not have sufficient stability to handle lateral forces. The winch’s pulling-power was over-dimensioned in
relation to what the vessel could in reality withstand as regards stability.

• The anchor-handling conditions prepared by the shipyard were not realistic. Nor did the Norwegian Maritime Directorate’s regulatory system make any requirement that these be approved.

• The ISM Code demands procedures for the key operations that the vessel is to perform, Despite the fact that anchor-handling was the vessel’s main function, there was no vessel-specific anchor-handling procedure for the “Bourbon Dolphin”.

• The company did not follow the ISM code’s requirement that all risk be identified.

• The company did not make sufficient requirements for the crew’s qualifications for demanding operations. The crew’s lack of experience was not compensated for by the addition of experienced personnel.

• The master was given 1½ hours to familiarise himself with the crew and vessel and the ongoing operation. In its safety management system the company has a requirement that new crews shall be familiarised with (inducted into) the vessel before they can take up their duties on board. In practice the master familiarises himself by overlapping with another master who knows the vessel, before he himself is given the command.

• Neither the company nor the operator ensured that sufficient time was made available for hand-over in the crew change.

• The vessel was marketed with continuous bollard pull of 180 tonnes. During an anchor-handling operation, in practice thrusters are always used for manoeuvring and dynamic positioning. The real bollard pull is then materially reduced. The company did not itself investigate whether the vessel was suited to the operation, but left this to the master.

• The company did not see to the acquisition of information about the content and scope of the assignment the “Bourbon Dolphin” was set to carry out. The company did not itself do any review of the Rig Move Procedure (RMP) with a view to risk exposure for crew and vessel. The company was thus not in a position to offer guidance.

• The Norwegian classification society Det norske Veritas (DNV) and the Norwegian Maritime Directorate were unable to detect the failures in the company’s systems though their audits.

• In specifying the vessel, the operator did not take account of the fact that the real bollard pull would be materially reduced through use of thrusters. In practice the “Bourbon Dolphin” was unsuited to dealing with the great forces to which she was exposed.

• The mooring system and the deployment method chosen were demanding to handle and vulnerable in relation to environmental forces.

• Planning of the RMP was incomplete. The procedure lacked fundamental and concrete risk assessments. Weather criteria were not defined and the forces were calculated for better weather conditions than they chose to operate in. Defined safety barriers were lacking. It was left to the discretion of the rig and the vessels whether operations should start or be suspended.

• In advance of the operation no start-up meeting with all involved parties was held. The vessels did not receive sufficient information about what could be expected of them, and the master misunderstood the vessel’s role.

• The procedure demanded the use of two vessels that had to operate at close quarters in different phases during the recovery and deployment of anchors.

• The increased risk exposure of the vessels was not reflected in the procedure. The procedure lacked provisions for alternative measures (contingency planning), for example in uncontrollable drifting from the run-out line. Nor were there guidelines for when and in what way such alternative measures should be implemented and what if any risk these would involve.

• The deployment of anchor no. 2 was commenced without the considerable drifting during the deployment of the diagonal anchor no. 6 had been evaluated.

• Human error on the part of the rig and the vessels during the performance of the operation.

• Communication and coordination between the rig and the vessel was defective during the last phase of the operation.

• Lack of involvement on the part of the rig when the “Bourbon Dolphin” drifted.

• The roll reduction tank was most probably in use at the time of the accident.

• The inner starboard towing pin had been depressed and the chain was lying against the outer starboard towing pin. The chain thereby acquired a changed
angle of attack."

[john]

Great find! I've added it to our blog:

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