Experience Feedback
Just after sunset on a calm evening, a large inbound container ship was approaching the pilot boarding position about a mile NE of the harbour’s breakwater entrance. As the pilot was to transfer from an outbound coastal tanker, he instructed the container ship to move to the starboard side (west) of the recommended track to avoid the tanker and maintain minimum speed, which, for this vessel was 7 knots.
As soon as the tanker had exited the breakwater, the pilot’s launch transferred him to the container ship. This operation lasted nearly eight minutes, by which time the vessel was very close to the breakwater and nearly parallel with it.
Immediately on reaching the bridge, the pilot realised the unfavourable situation but instead of consulting the master or aborting the approach, he ordered half ahead and hard-astarboard, with the intention of steering the ship around the breakwater head. The intended track now involved a very sharp starboard turn of almost 130º at minimum steerage way, keeping close to the breakwater head.
The bridge team did not appreciate that this manoeuvre was beyond the ship’s turning ability. The bridge team’s vision was blinded by the bright city lights to the south, which were virtually doubled in intensity by the reflection from the calm water. This affected their situational awareness and they failed to sight the red lightbuoy marking the southern limit of the approach channel into the basin.
The ship started picking up speed but the head responded very slowly. The pilot ordered the bow thruster full to starboard, but at the prevailing speed this had no effect. Realising that the ship had strayed well off the desired safe track and heading, he then ordered the two tugs (700 BHP forward and 1800 BHP aft), to push with maximum power from the port bow and port quarter respectively. This manoeuvre only served to cancel the rudder’s action, as the larger after tug’s force was enhanced due to the very long lever between the ship’s pivot point and tug’s push point. Under the circumstances, the smaller bow tug had no effect at all. Belatedly realising the dangerous position, the master rang emergency full astern, but this did not prevent the ship from overshooting the red buoy on the wrong side and she grounded on a charted underwater rock.
The ship almost rebounded with the impact. With the engine still going astern, she floated off on her own. Immediately, the bow thruster motor low insulation alarm was triggered and the breaker tripped. The officer on the forward mooring station was ordered to check the bow thruster space. He reported that it was flooding and the motor was already submerged.
Once back in the channel, the engine was stopped and the tugs came around and made fast their tow lines on the starboard bow and quarter. The ship was berthed port side to the container berth. A class surveyor with divers attended before midnight and after an underwater survey, issued a conditional certificate of class to sail to the nearest major port (16 hours’ sailing time at reduced speed) and carry out a docking survey.
Extent of damage
1. Bottom plating on port side of keel buckled extensively for a length of about 15 metres from stem and holed in fore
peak tank and bow thruster space;
2. Bow thruster motor windings and wiring damaged by sea water;
3. Forepeak tank vent heads burst and detached from base due to the shock pressure wave generated by the water inside the fully-ballasted forepeak tank.
Root cause/contributory factors
1. Unplanned deviation from planned track during the critical final stage of the passage;
2. Pilot wrongly gave navigational priority to smaller outbound vessel;
3. Bridge team lost situational awareness and continued to navigate along wrong track;
4. Pilot boarded too close to harbour entrance and failed to recover from a dangerous navigational situation, and compounded the error by ordering half ahead;
5. Failure to understand ship’s manoeuvring characteristics;
6. Poorly considered deployment of tugs, which ideally should have made fast on the starboard side before passing the breakwater;
7. Failure to let go anchors in good time;
8. Bright shore lights and reflection on the water affected the efficiency of lookout.
Source; Mars/Nautical Institute
