The Gibraltar Maritime Administration (GMA) released an investigation report regarding the collision of the bulk carrier OS 35 and the LNG carrier ADAM LNG and the subsequent grounding of OS 35.
Summary of the incident
OS 35, loaded with a cargo of steel rebar, weighed anchor in Gibraltar Bay on completion of bunkering. OS 35 then manoeuvred with astern propulsion, with the bow swinging to starboard and the speed astern increasing to 3 knots. The master, concerned that OS 35 was drifting — due to the effects of tidal flow and wind — towards the anchored ADAM LNG, then set the engine to full ahead and the rudder hard to port.
The starboard swing and speed of OS 35 reduced, and the vessel then set towards ADAM LNG. The starboard side hull of OS 35 collided with the bulbous bow of ADAM LNG.
The hull of OS 35 was breached in holds 2 and 3, with water quickly flooding into the two holds and then hold 1. ADAM LNG sustained minor steel damage to its bulbous bow. The Port of Gibraltar Vessel Traffic Services (VTS) directed OS 35 to proceed to the east of Gibraltar and to ground the vessel close to shore in order to prevent it from sinking in deeper water and remain in British Gibraltar Territorial Waters.
OS 35 grounded with the anchor lowered and was then assisted with salvage support, which was available in the port.
The investigation found that the master and bridge team did not monitor the manoeuvre effectively and made an error in their understanding of the effects of the tidal flow and wind.
The Gibraltar Port Authority (GPA) Vessel Traffic Services (VTS) monitored the manoeuvre; however, their interventions did not alter the actions of the master or prevent the collision.
Conclusions
- The master of OS 35 made an error of judgement, which was not detected by the bridge team, departing from the Western Anchorage. As OS 35 was manoeuvring astern, the ECDIS track showed that, as the heading continued to swing to starboard, OS 35 would have passed well clear ahead of ADAM LNG in light wind and negligible tidal flow. However, the master’s perception was that OS 35 was drifting towards ADAM LNG and that the vessels would collide. This error led to the master of OS 35 setting the engine to full power ahead, and the rudder hard to port. Rather than avoiding the collision, this action led to the collision of OS 35 with ADAM LNG at a speed of 3 knots, with the stern of OS 35 swinging towards the bow of ADAM LNG.
- Pilotage is not compulsory for departure from the Gibraltar Western Anchorage, and the master did not choose to take a pilot. The pilotage information provided does not recommend or provide guidance for requesting a pilot for departing the anchorage. Had a pilot been embarked, it is considered very likely that an alternative manoeuvre would have been used to depart the anchorage, which would not have included the prolonged astern manoeuvre.
- The frequency of collisions on departure from the anchorage is low. However, the potential impact of vessel collisions is high, with the associated risk of serious oil pollution. No significant collisions, with a pilot on board — with around 8,700 pilotage acts carried out each year — have been formally investigated during the same 15-year period.
- Had a pilot been onboard, it is considered very likely that the collision would have been prevented. The option of compulsory pilotage would provide an effective barrier to similar future accidents occurring. The VTSO did not advise, as was usual practice, that OS 35 should manoeuvre to the west from the Western Anchorage prior to heading south into the Gibraltar Strait. VTS was not aware of the change of OS 35’s intended manoeuvre until it was too late to prevent the collision, and their intervention was ineffective. When VTS warned OS 35 that a risk of collision existed, the collision had already occurred. Had VTS been aware of the intended manoeuvre of OS 35 prior to permission being given to depart the anchorage, then they would have been better prepared to verify whether the manoeuvre was being carried out effectively. ADAM LNG was, in the time available, unable to take any action that would have prevented the collision from occurring once the risk of a collision became apparent.
- The response by VTS following the collision was effective. VTS correctly predicted, despite the information provided by the master of OS 35, that a collision had occurred. The incident was quickly escalated to the highest levels of the Gibraltar Administration, and the decision to ground the vessel to the east of Gibraltar to prevent sinking in deeper water, or outside of BGTW, was quickly made and effectively communicated to the master of OS 35.
- Had the VDR been fully functional on board OS 35 and ADAM LNG, the investigation would have been provided with a better understanding of the actions taken on the bridge of OS 35, and more frequent positions of the anchored ADAM LNG would have been provided.
