一艘满载26000GT的集装箱船正准备离港开往里约热内卢，船长完成了对所有机器设备和航海仪器的测试后，开始解缆使船舶单绑，引水登轮，同时有一艘拖轮被指派协助离港。拖轮连接并拉紧两根艉缆，很快拖轮和船舶推进器使船舶平移离开码头。
引水和船长准备使船舶右转进入航道。在船舶离开码头50米远的时候，拖缆突然从拖钩上松了下来，驾驶台并没有发出这一操作指令，也没有收到执行这一操作的通知。
在拖轮船长和引水用本国语言交谈几秒之后，拖轮船长命令拖轮离开，引水也立即确认了这一指令。在船尾接受这一指令的三副说，在指令下达之前，拖轮早已松开缆绳。那时，引擎和螺旋桨都没有工作。艉甲板的船员于是开始绞缆绳，使之离开水面和螺旋桨区域。同时，船长全速开动船艏推进器以确保船舶远离码头。
然后，拖轮移到了船的右舷，开始推动船舶。
拖轮扔到水里的缆绳被强烈的水流冲向船艉水面下。艉甲板的船员没能把拖绳拉出水面，最终两根缆绳被卡死。船长得知这一消息，并没有试图把车调为 “低速前进” ，引擎和螺旋桨始终没动。
在成功进入航道后，船长下令，关闭侧推器引擎，并转动船舵以使舵叶转动，希望这一操作能使卡死的缆绳松开。然而，在几次尝试之后，显然这不管用，需要专业的救助。船长不得不再次将船靠码头，30分钟后船上所有的缆绳收紧在码头上了。
水下作业公司被请来查明情况，发现这两根缆绳被绞死螺旋桨上。为了从螺旋桨解开这两根缆绳，船舶延误了4天。
协会希望通过该案例，使相关人员注意：
- 要对所在港口水流对缆绳的影响有充分的预估
- 艉甲板船员必须及时报告现场情况
- 熟悉相关离港操作指示
- 船长/引航员交换信息的时间和内容
- 拖轮船长的操作指令
- 如何监控引水与拖轮船长的交流（本国语言？）
- 离港前相关方通信设备的测试
通过分析该案例的事故原因，协会希望会员在船舶操作过程中，加强信息及时、有效的交流，同时提高操作技能，准确判断港区水流情况，确保船舶各项操作的安全。
详细信息请参阅附件。
Case study : Lines in the water
The Captain was apparently ready to leave port with his 26 000GT fully laden containership, bound for Rio de Janeiro. After the completion of all tests of machinery and navigational equipment, the vessel started to single up lines. The pilot boarded the vessel and one tug was assigned to assist with the departure. The tug fastened two ship lines on the aft of the ship, and soon after the tug and the ship’s bow thruster moved the ship in aparallel direction to the pier.
Both the pilot’s and the Master’s intention was to make a turn to starboard into a fairway channel. When the ship was about 50 metres away from the pier, the towing lines were suddenly released from the tug’s hook – without the bridge team instructing to do so nor having been notified of the intention to do so.
A few seconds later and after a conversation in the local language between the pilot and tug Master, the Master ordered to let go of the tug. This order was confirmed by the pilot immediately thereafter. In reply to the order the third officer, who was stationed at the aft station advised the bridge that the towing lines had already been released by the tug before the order was given. At that moment, the engines were stopped and the propeller idle. The aft station now started to heave lines in order to get the lines out of the water and away from the propeller area. In the meantime the Master used the bow thruster at full to port to keep the vessel away from the pier.
The tug had now shifted position to starboard side and started pushing as ordered.
The towing lines in the water, left by the tug, were caught by the strong current and went underneath the stern. The crew on the aft station were not able to pull the lines out and recover them from the water, the 2 lines were eventually blocked. When the Master heard this he did not attempt to set the engine telegraph to “Dead slow ahead” and the engines remained stopped and propeller idle.
After a successful turn into the channel, the Master ordered that the engines be shut down and to rotate the propeller shaft by means of turning the gear hoping that this maneuver would release the blocked lines. However, after several attempts it became clear this would not succeed and that professional help was required. The Master decided to put the ship alongside again and 30 minutes later the ship had all lines fastened to the pier again.
A diving company was hired to assess the situation and it was then discovered that the two lines were stuck in the propeller. The ship was delayed for 4 days while retrieving the line from the propeller shaft.
Keywords for discussion:
- Evaluate the effect of local current on the lines in the actual port
- Awareness of crew on aft station to report situations promptly
- Departure briefing with parties involved
- Time spent on and content of a Master/ Pilot exchange of information
- Involvement of tug master in briefing
- How to monitor the communication between the pilot and tug Master (local language?)
- Test of communication equipment between involved parties prior to departure
See attached file : Gard AS – Case study no 23 – Lines in the water.pdf
