Stolt Tern Grounding


To read the original illustrated pdf article click on Back Issues: October 2005

I have decided to make the MAIB report into the grounding of the Stolt Tern the feature subject this quarter because the report covers many of the issues currently high on the UKMPA agenda. The grounding occurred in daylight and near perfect conditions and the pilotage was undertaken by an experienced pilot who had piloted this vessel and her sister ships many times to the same berth. The incident thus confirms that no matter how many times a pilot has undertaken a particular passage, pilotage is never “routine” and pilots have to be permanently vigilant and be prepared for the unexpected. Only high quality training can help to prepare a pilot to cope with the unexpected.

The pilot and master both exchanged information in accordance with current “best practice” but the pilot’s passage plan is criticised in the report for not being sufficiently detailed in providing clearances from the breakwater and tracks to the

berth. I must admit that I disagree with this criticism because one of the primary roles

of a pilot is to be able to have flexibility during a passage rather than running on fixed tracks and if he has been trained professionally his detailed knowledge of the district permits him to know where the ship can and cannot be positioned depending on the vessel’s draft with respect to the height of tide. Pilots have to deviate from the “track” to facilitate overtaking or collision avoidance and in my experience the presence of a fixed track on a passage plan can cause more problems than it can potentially resolve in that deviation from a rigid track will cause the OOW to be constantly questioning the pilot and introduce doubt, confusion and distraction within the “bridge team”. Those who pilot warships will be only too aware of this! I feel that “best practice” would be that if the pilot is to depart from a “normal” track then he should inform the master of the reason and provide details of the height of tide in relation to the draft and provide the minimum UKC to be anticipated during the deviation. In this way the “bridge team” (as much as it exists in reality!) will be reassured and the OOW can, if he wishes, double check the calculations. Many vessels now shade-in shallow areas on the chart where the vessel should not navigate and this is considered good practice by

inspectors. Unfortunately, such shading is usually based on chart datum and takes no account of tidal height. For many tidal restricted vessels the whole piloted passage

can be undertaken through these shaded “no go” areas! Practically, it would be impossible to produce a passage plan shading in the actual no go areas unless the

vessel was fitted with an advanced ECDIS incorporating “real time” tidal data corrected for any tidal surges or cuts in tidal level. To the best of my knowledge such real time tide (and in Australia swell) corrected ECDIS is limited to a few specialist, port specific portable pilotage laptop units. Once things start to go wrong the Master pilot relationship is critical and unless both the Master and the pilot realise that the plan is unravelling and, more importantly, are in agreement as to how the situation can best be resolved then an incident is almost inevitable. One common factor in all pilotage related incidents is the rapidity with which a routine passage or manoeuvre transforms into a disaster. In this case it appears that the approach went from normal into a grounding scenario within 2-3 minutes. The reason on this occasion appears to be that the Master over ruled the pilot by reducing speed to less than that ordered by the pilot and used the bow thruster without being instructed. I believe that in this case, even if a “safe” track had been placed on the chart, the grounding would still have occurred

because the master (being unfamiliar with the port) was obviously concerned that the

vessel was going too fast and not swinging to starboard fast enough and thus reduced

the pitch more than requested and then whacked the thruster to starboard. His actions were therefore entirely successful in achieving what he thought was required rather than what the pilot had requested!! This incident happened whilst the vessel was under pilotage and therefore the grounding will automatically be put down to “pilot error” by the insurers! (see p.14). The report highlights the need for pilots to be fully trained and recommends that ports fully support pilots by providing on-going professional development. Further to this, the report acknowledges the importance of pilots being subjected to National Occupational Standards. This is what the UKMPA have been trying to implement since the NOS document was produced in 2001 and hopefully the

recommendations of the MAIB will accelerate the conclusion of this work. Finally the MAIB measures Holyhead port’s compliance with the requirements of the Port Marine Safety Code and also for the first time refers to the “best practice” detailed in IMO resolution A960. This report therefore reinforces the arguments made by the UKMPA of the need to draw up a new Pilotage Act to incorporate the PMSC and pilots’ NOS.

The following is an edited version of the full MAIB report.


At 0915 on 1 December 2004, Stolt Tern approached the pilot embarkation position off Holyhead with a cargo of 4000t of gas oil. On arrival on the bridge, information was exchanged between the master and the pilot. The pilot was given the ship’s pilot information card and supplementary information regarding her Becker rudder that reductions in speed should be made gradually and not when changing heading. The pilot gave the Master the port passage plan to the intended berth. The pilot advised the master to alter course to put the breakwater fine on the starboard bow and manual steering was selected.

The master controlled the pitch control lever, and the third officer was on the helm, except when relieved by the master to allow him to plot fixes on the paper chart.

The speed was reduced to slow ahead when about 5 cables from the breakwater. Soon after, the pilot advised a 10° alteration to starboard to aim towards a prominent chimney. The third officer applied 5° of starboard helm. The master also gave a short burst of the bow thruster to starboard, and reduced to dead slow ahead, in accordance with advice he thought the pilot had given.

The ship started to swing quickly to starboard. The pilot commented that the stern was being influenced by the tidal stream and ordered ‘midships’ followed by ‘steady’. As the third officer applied 20° of port helm, the pilot advised ‘hard to port’. Although 35° of port helm was applied, and the bow thruster was thrust to port, the ship continued to swing quickly to starboard.

Realising that the ship was swinging towards the breakwater, the pilot advised the master to ‘stop’ followed by ‘full astern’. The third officer responded by stating in Filipino that this action would accelerate the swing towards the breakwater end. Accordingly, the master increased to half ahead and increased the port helm to 65°. Moments later, at 0940, the ship grounded on a patch of shoal water to the south of the eastern end of the breakwater. Estimates of the speed of grounding range from 2 to 6 knots.


The vessel was re-floated with the assistance of the tug Afon Braint at 1120, and was secured alongside Terminal 4 at 1215. There was no pollution.

Following a temporary repair, the vessel sailed to Rotterdam for permanent repairs.


The wind was south-east force 1-2, and the sea was calm. The predicted mean rate of the tidal stream in the position of tidal diamond ‘B’ was 102° at 0.5 knot.


The course recorder was found to be reading 10 minutes slow, and 10° low. The ship was fitted with a propeller pitch recorder, but this was not working. The port’s radar was operating but did not have a recording capability.


The chart in use for entry into the port was BA 2011, the largest scale chart available and generally corrected up to date The port passage plan did not show the intended routes to the port’s berths.


The pilot was 65 years old and was raised in Holyhead. He had served on board deep-sea ships, and had been qualified as a master since 1966. From 1970, he worked onboard ferries operating out of Holyhead, where he held a PEC. He was promoted to Master in 1980 and served continuously in that role until 1993. After ceasing to be a ferry master, he remained employed in the port overseeing dredging operations, and as a standby pilot. He became the port’s principal pilot in 1999. He conducted between 150 and 200 pilotage acts each year. The pilot had not experienced any accidents or near accidents during his time in Holyhead, and the Port Authority had not received any adverse comments from third parties regarding his performance. He was well respected for his knowledge and shiphandling ability by the port’s senior management, and maintained a keen interest in the operations of the port and in 2002 had also suggested that a permanent navigation mark be placed to mark the shoal water to the south of the breakwater end. In addition to his pilotage duties, the pilot had also voluntarily assisted the harbourmaster in the oral examination of over one hundred PEC candidates. He was well rested when he arrived on board Stolt Tern.


The pilot expected the ship to be set to the east by the tidal stream as she proceeded towards the harbour entrance. He estimated that the rate would be a maximum of between 2 and 3 knots, and anticipated this would cause the ship to pass between 1.5 and 2 cables off the breakwater end. The pilot was aware the ship might experience a turning moment to starboard when for a brief period, the stern would continue to be influenced by the tidal stream, whereas the bow would not, and had identified a need to ensure that the ship was on a steady course during this period.


The pilot stated that he never advised ‘dead slow ahead’, or for the bow thruster to be used when initially altering course to starboard. After port helm was applied to steady the ship, the pilot remembers the ship being steady on course for about 2 minutes, and that it was not until the breakwater head was on the starboard beam, at a distance of between 1.5 and 2 cables – that the sheer to starboard developed. From where the pilot was standing, he could not see the CPP control lever, or ship speed indications, but could see rudder angle and propeller pitch repeaters. He was conscious of the master making adjustments to controls on the console.


When the pilot was retained as the port’s principal pilot in 1999, there was no formal process for the authorisation of pilots in place. His PEC was transferred to a pilot authorisation without an examination being conducted. During the pilot’s time in post no formal checks had been made on his performance. The pilot was not employed on board ships over 10000grt using the Aluminium jetty. Mersey pilots were employed on these ships because of their need for tug assistance, The port’s pilotage committee was chaired by the harbourmaster and comprised the port’s major users, including the pilot, and other interested bodies. The committee’s agenda typically included all aspects of the safety of navigation, and pilotage within the port.


The PMSC was developed by the Department for Transport and was implemented in December 2001. The code introduced the principle of a national standard for every aspect of port marine safety, and although the code was not mandatory, the Department for Transport expected every CHA to comply with its requirements. These included the completion of formal risk assessments of marine operations.

National Occupational Standards

In its review of the PMSC, published in November 2004, the

Department for Transport concluded that:

MCA should continue to engage with the industry on occupational standards until it is generally established that these underpin the recruitment and statutory authorisation of those key positions – this needs to include the promotion of formal training in assessment.

National occupational standards for pilots have been agreed and accredited with the QCA. However, the assessment criteria for their implementation have yet to be agreed.


Resolution A.960(xxiii) contains recommendations on the training and authorisation of pilots, and recommends that harbour authorities should satisfy themselves that pilots continue to possess up to date knowledge (at intervals not exceeding 5 years) of local navigational issues, current regulations and any other specifically related local issues. It also states:

Every pilot should be trained in bridge resource management with an emphasis on the exchange of information that is essential to a safe transit. This training should include a requirement for the pilot to assess particular situations and to conduct an exchange of information with the master and/or officer in charge of the navigational watch. Maintaining an effective working relationship between the pilot and the bridge team in both routine and emergency conditions should be covered in training. Emergency conditions should include loss of steering, loss of propulsion, and failures of radar, vital systems and automation, in a narrow channel or fairway.

The harbourmaster of Holyhead was unaware of the content of Resolution A.960(xxiii).


After the pilot embarked in Stolt Tern, the initial passage towards the breakwater proceeded as planned. However, as a small alteration of course to starboard was made to the north of the breakwater, the turn could not be checked and the ship started to turn from a course of 139° at 0937, and grounded at 0940 on a heading of 232°. It is estimated that the ship’s mean ground speed during this period was between 3 and 4 knots. In the absence of any indication of a machinery malfunction or failure, the loss of control was probably due to one, or a combination, of several factors.

First, the time interval between the engine movements from half ahead to dead slow was short, and the resulting reduction in speed would have been quite rapid. Given that the ship was known to be extremely right-handed and that the pilot information card warned against reducing speed and changing heading at the same time, a sheer to starboard was a likely outcome.

Second, as Stolt Tern passed the end of the breakwater, her bow would have entered the still waters to the south, while her stern would have been set to the east by the tidal stream to the north of the breakwater. This would have exacerbated the ship’s turning moment, and her slow speed would have prolonged her exposure to this effect. Third, although the time the bow thruster was used at the start of the turn was stated by the master to have lasted only a few seconds, its use is likely to have had an influence given the ship’s slow speed. In conjunction with the 5° of starboard rudder, which according to the information in the pilot card equated to about 15° of conventional rudder, this could have induced a high rate of turn unless quickly checked.

It is impossible to determine if the grounding would have been avoided had the master followed the advice of the pilot and put the engines astern. The master’s decision to ignore this advice, and to increase speed and rudder, was based on his knowledge and experience of the ship’s manoeuvring characteristics. It is correctly the prerogative of the master to take such action, whenever he considers appropriate.


Before entering Holyhead, relevant information had been passed between the pilot and the master.

However during the execution of the passage plan the pilot was not integrated into the bridge team. The master’s rapid reduction of speed, and his use of the bow thruster, resulted from poor communication between the master and the pilot. The pilot was not aware of the action taken because the master did not inform him. He was concentrating on conning the ship and did not monitor the master’s actions.

The pilot estimated the ship’s position and movement by eye. He did not ask for any of the additional information available to the bridge team, such as ranges by radar or speed over the ground, nor was any of this information offered.

The pilot was isolated from the decision-making process during the discussions between the master and third officer, in Filipino, immediately before the grounding. The integration of pilots into a bridge team is essential if passages in pilotage waters are to be conducted safely. On this occasion, it is not certain why the master reduced speed to dead slow. He was operating the CPP controls, and was aware of the ship’s handling characteristics. However, better teamwork and a more effective working relationship between the master and third officer, and the pilot, might have helped to recognise what was going wrong with the plan in sufficient time for corrective action to be taken.

It is understood that some of the larger ports arrange for their pilots to attend tailored bridge simulator courses as part of their ongoing professional development. Such training would probably be of benefit to all pilots.


The intended passing distance off the breakwater allowed insufficient sea room and time for corrective action to be taken. A similar accident could easily have occurred had the ship suffered a mechanical failure.

There was no reason why a greater clearance could not have been planned. However, the pilot had followed the intended route and passed the breakwater many times without incident, and it had become custom and practice.

Although the bridge team had produced a pilotage plan for entry into the port, the lack of tide tables indicates that the master was reliant on the services of the pilot for this information.


In keeping with the Port Marine Safety Code, the port of Holyhead was operated under a safety management system. Assessments had been made of all identified risks related to marine activities, and these had been periodically reviewed.

The simple and cost free precaution of allowing a larger safety margin when passing the breakwater end was not identified. This was particularly relevant to the ships on passage from the pilot station to Terminal 4, which needed to make a large turn around the breakwater end. The precaution was probably not identified due to the fact that the entry to the port is relatively straightforward, there was no experience of previous accidents in this area, and the port’s management, which was very experienced in ship and port operations in Holyhead, was highly respectful of the pilot’s ability and experience. Risk assessment is a very useful tool to quantify and reduce risk through the identification and implementation of suitable control measures. However, unless the control measures themselves are regularly reviewed to ensure that the risks are being kept as low as reasonably practical, the effectiveness of the risk assessment process is diluted. Liaison with the persons providing the control measures is essential to achieve this.


Since the pilot had been in post, the port had improved and formalised its procedures for the authorisation of pilots. This was demonstrated by the authorisation procedure followed for the standby pilot, and the pilots employed from the Mersey. The requirements for PECs were also clearly defined. The authorisation of the pilot on board Stolt Tern pre-dated these procedures, and he had never undergone any formal assessment in his role. However, the harbourmaster had monitored the pilot’s performance by accompanying him on the occasional act of pilotage, and by witnessing his shiphandling from ashore.

Local navigational knowledge and shiphandling are obviously pivotal to a pilot’s performance but there are other areas in which a pilot must also be proficient. It is difficult for harbour authorities to effectively monitor performance in all aspects of a pilot’s work, but a requirement for all pilots to have a qualification based on national occupational standards would at least provide a reliable base from which to start.


A number of departures from the company’s procedures and material deficiencies, with respect to navigation and bridge management, were evident on board Stolt Tern. These included: the lack of tide tables; the chart in use not being corrected up to date; the lack of a helmsman on the bridge; the lack of a bridge team brief prior to entering the port; the lack of assistance provided to the pilot in terms of his familiarisation with the bridge equipment and general support; the interchanging of the master and third officer on the helm; the use of Filipino rather than English just before the grounding; the misalignment of the course recorder; and the non-functioning of the propeller pitch recorder.


The BPA/UKMPG marine and pilotage group is recommended


Highlight to members of the BPA and UKMPG the importance of reducing the level of risk identified to as low as reasonably practical when conducting risk assessments, and the importance of ensuring that the effectiveness of any resulting control measures is reviewed regularly.

Reinforce to the members of the BPA and UKMPG the need to ensure a meaningful exchange of information between pilots and masters rather than merely the completion of a checklist. Such exchanges should cover all relevant areas such as the vessel characteristics, bridge team organisation and duties.

The MCA is recommended to:

Expedite and resource, through the national occupational standards working group of the PMSC steering committee, the requirement for national occupational standards for pilots to be a prerequisite for their recruitment and statutory authorisation.

Stolt-Nielsen Transportation B.V. is recommended to:

Review its safety management and auditing processes with a view to improving the safety culture among its ships’ crews, and encouraging a more open reporting regime.

Expedite its programme of bridge resource management training for its masters within its European coastal fleet, and ensure that pilot integration is included in the course syllabus.

Full report available on the MAIB website:


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