Breaking of mooring lines whilst mooring m.v. Edisongracht between ...

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Spindle of the anchor chainstand roller fairleadFigure 6: Crew member positions and cover of the mooring lines just before the accidentAs a result, the mooring line immediately broke in half. The break occurred just behind the splice ofthe mooring line’s eye. One of the AB’s was fatally injured by parts that flew off the mooring line.The parts also hit the second officer, who fractured his upper leg and sustained a head injury fromfalling on the deck.After this, the vessel was only secured by the mooring line from the port winch. The tension on thismooring line became too high and, ultimately, the line broke as a result of overloading. The end ofthe broken starboard mooring line showed a nearly straight sharp break (see figure 7). The portmooring line, on the other hand, showed a frayed break pattern (see figure 8).Figure 7: Photo of the starboard mooringline fracture surfaceFigure 8: Photo of the port mooring linefracture surfaceAfter both mooring lines had broken, the Captain manoeuvred the vessel to the north of themooring buoys to ensure the vessel would not drift away and hit the quay that was being built. Thevessel was finally moored at another quay at 10:05 a.m.- 11 -
4 ANALYSIS4.1 Before the accidentWork is being performed in Kwanda Base to build a new LNG terminal. The most recent sea chartfor this area (BA 658), which was also available on board of the m.v. Edisongracht, specifies thatdue to these continuous adjustments to the port there is no general up-to-date and reliableinformation (i.e. water depths, buoyage systems, current profiles, port facilities, etc.) about thelocal situation. Up-to-date information needs to be obtained from the local port authorities. Awarning specifically for this area is provided in the Admiralty Sailing Directions (Africa Pilot Vol. II),which was available on board the m.v. Edisongracht, that vessels may be very difficult tomanoeuvre or not be manoeuvrable at all as a result of the large differences between surfacecurrents and undercurrents.The Captain could only find reliable information about the time of high and low water with the fallin the tide tables. The Captain was therefore aware that it would be spring tide 9 that morning. Forthe required voyage planning the Captain also received information from the local representative ofthe offshore company. Also, information issued by the shipping company was used. Thisinformation was based on earlier experiences gained in Kwanda Base during the previous voyagesthat were performed for this project. It was the third time that the Captain performed thismanoeuvre. As such, he as well as the other crew had experience with the mooring manoeuvre tobe performed between the mooring buoys. The Captain also knew that using the anchor during themooring manoeuvre was not allowed in the port.The Captain had been informed by the shipping agent that the offshore company with permissionfrom the port authorities, had arranged that the pilot would come on board in the Pululu channel at6:00 a.m. This would mean that the vessel could execute the mooring manoeuvres atapproximately 6:00 a.m., at which time it would be nearly slack tide. During slack tide there is noappreciable tidal current. The Captain had tried to contact the port authorities almost every hourthat morning as from 4:00 a.m. He was told by the port authorities that the pilot would not boardthe vessel at the agreed time. A reason was not given. After the Captain was assured by theauthorities that the pilot would board soon, he was given permission to already sail into the PululuChannel. He started to haul in the anchor at approximately 06:50 a.m. At that moment the Captainknew that he could not execute the mooring manoeuvres on slack tide. Next, at around 07:30 a.m.he set course to the entrance of the channel. The vessel reached the entrance of the channel at07:50 a.m. The Captain, still waiting for the pilot, kept the vessel running and tried to contact thepilot station several times. The pilot station assured the Captain each time that the pilot wouldboard soon.The pilot eventually arrived on board that morning at around 8:30 a.m. when the vessel wasalready sailing near the mooring buoys. Due to the late arrival of the pilot, the mooring manoeuvrewas initiated 2.5 hours later than planned. As a result, the mooring manoeuvre was executed whenthe tidal current was nearly at its peak: the moment at which the current is at its strongest.Moreover, the current was also more stronger than usual because of the spring tide(outgoing/ingoing tide approximately 1-3 knots on average and, with spring tide, 2-4 knots 10 ). Thisspring tide also caused the current flow not to run in the North-South direction of the channel, as910Spring tide: When the Sun, Moon and Earth form a straight line (which occurs twice a month), theycombine their forces and attract more water. The level of the water is then higher with high tide andlower with low tide. More flow is created between the tides than with the normal tide due to thisdifference in fall.Source: Admiralty Sailing Directions (Africa Pilot Vol. II, 2007 edition).- 12 -
Page 1 and 2: Breaking of mooring lines whilst mo
Page 3 and 4: Investigation of very serious marin
Page 5 and 6: 1 SUMMARYDuring a mooring manoeuvre
Page 7 and 8: High tide time/water level 4 : 05:3
Page 9 and 10: Figure 2: Local map of Pululu appro
Page 11: position. Both tugs on the vessel's
Page 16 and 17: The shape of a guide roller determi
Page 18 and 19: 5 CONCLUSIONS• The moment at whic
Page 20 and 21: Official vessel number.National reg
Page 22 and 23: ANNEX 3: HEALTH AND SAFETY SHEET MO
Page 24 and 25: - 23 -
Page 26 and 27: - 25 -
Page 28 and 29: - 27 -
Page 30: The Dutch Safety Boardtelephone +31

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