| Bilgi Giriş Tarihi | 26.10.2017 |
VERY SERIOUS MARINE VASUALTY: ABLE SEAMAN STRUCK BY DEBRIS FROM EXPLODINGWINDLASS MOTOR
What happened?
While waiting for its berth to load a cargo of coal, a 39,000 GT bulk carrier anchored in a designated anchoring position as provided by the port authority. The next day the port authority instructed the vessel to shift its anchor position further south, and the vessel then re-anchored and brought up to seven shackles on deck on its port anchor.
The nature of the sea-bed at a depth of 53 metres was a mixture of fine sand and shells. Two days later, while still at anchor the wind speed increased to Force 6. Sea swell was about 2-3 metres.
The chief mate was sent to check on the anchor cable. The officer reported dust coming out of the windlass, there was excessive weight on the anchor cable and the bow securing pin was bent.
The bow securing pin from the starboard anchor was used to replace the one on the port anchor cable, which also got bent shortly afterwards. A stainless steel rod was then fabricated on board to replace the newly bent pin.
At night time the duty officer, who was asked to check on the condition of the cable, reported that the distance from the nearest ship was reducing and confirmed that own vessel was dragging anchor. Stations were called and main engines were prepared. The hydraulic power pack for the windlass was switched on.
The chief officer, along with six crew at the forecastle, prepared to heave the anchor. As the cable was up and down, the master used the engines (half ahead) to keep the vessel away from dragging onto the nearby ship.
The anchor cable lay astern as the vessel moved ahead and dredged on its anchor. Subsequently, moderate weight came on the cable and the cable came back to up and down. Heaving of the anchor resumed.
The master then notified the port authority of his intention to shift the anchor position. Subsequently, the lay of the anchor cable changed from up and down to ahead medium stay to abeam short stay to astern.
At some point when the cable was leading astern the anchor could not be heaved up any further. As the attempt to heave the anchor continued, the crew saw sparks flying out of the port windlass. The windlass operator, an able seaman, applied the brake on the anchor cable.
Soon after, the windlass motor exploded and flying debris from the explosion hit the windlass operator on his neck and jaw. The power to the windlass was stopped by the other crew and the brake was re-applied. On-site first aid and pressure to the wound of the injured operator were applied by the crew.
The master requested medical assistance. An hour later the injured operator stopped responding and was declared deceased by paramedics an hour thereafter.
The port anchor was subsequently heaved up using the motor from the starboard windlass. The anchor was noted to be fouled with an abandoned anchor chain on the sea-bed.
Why did it happen?
Operation of the port windlass hydraulic motor in the reverse direction would have resulted in severe rise of hydraulic pressure inside the motor due to the positive displacement pumping action, causing the motor to explode.
The loading capacity of the windlass was exceeded due to dragging anchor, shock loading due to heavy rolling and pitching of the vessel in severe conditions, frictional force due to chain rubbing against the hull and fouling of the anchor by an abandoned anchor chain.
The master had not fully assessed the future weather conditions at the anchorage to prepare for heaving the anchor before the weather worsened.
The windlass manufacturer had not provided any safety guards around the windlass on existing vessels to protect the crew. These however had been provided on new vessels.
What can we learn?
Appropriate training and familiarization on board is necessary to ensure the correct handling procedure for the anchor windlass and vessel, with special emphasis on circumstances such as anchor dragging, adverse weather conditions, anchor fouling, etc. which may place excessive load on the windlass equipment.
Severe weather conditions can place excessive loads on the windlass motor and ship’s crew should take appropriate precautions in a timely manner to avoid such loads.
Physical guards may protect crew from potential explosion of a windlass hydraulic motor.