Loss of a vessel

The company involved was contracted to conduct a seabed survey for a proposed pipeline and the vessel involved was tasked with carrying out the work scope.

On arrival at location the survey operations commenced by deployment of an acoustic transceiver pole through the vessel’s hull via a gland, support stool and gate valve. The system is located in the ship’s engine room.

The transceiver pole weighing approximately 500 kg and 5m in length was lowered by a chain block assembly. At some point during the lowering and for reasons unknown, the pole fell freely some four to five metres. The retaining collar and supporting steelwork were destroyed by the inertial energy of the pole thus the pole was lost to sea.

Thereafter there was ingress of water into the engine room from the open gland. The control wheel to the gate valve, which was situated at the base of the support stool was almost immediately submerged preventing access by staff to close it.

The watertight doors to the port and starboard shaft tunnels were closed and the engine room evacuated. Distress calls were initiated, the company’s office advised and a nearby support vessel closed in to render assistance and to receive all non-essential personnel off the vessel. Assistance was also obtained from a nearby coalition force vessel with helicopter support. Once it was quickly established there was no risk to personnel efforts were focussed on saving the ship.

Regrettably only one of three pumps landed onboard the vessel was operable. Given this situation all remaining personnel were removed, thereafter the vessel remained afloat a further three hours, sinking in 3,000 metres of water.

Both the Master and his team, supported by the various vessels, agencies and the company emergency response team, managed the whole nine hour incident in a controlled manner. The entire crew of 29 were transferred by vessel’s rescue craft without injuries or incident of any kind.