Chaos and Consequences

Malcolm Latarche

Malcolm Latarche · 02 May 2017


Whether or not a butterfly flapping its wings can cause a tornado as the chaos theory suggests, it is certain that actions, or indeed inactions, often have unforeseen and undesirable consequences. The loss of the converted VLOC Stellar Daisy at the end of March was a tragic event. Any incident that leads to the death of seafarers cannot be called anything else especially when so many are involved. Merciful at least two survived to tell at least part of the tale that lead to the loss of their compatriots lives and their ship. For the ship to break into two as the survivors say, it is hardly likely that the cause of the ship’s loss was liquefaction of the cargo as some have hypothesised, although initial reports that the owners had received a communication from the vessel saying that it was taking water on board and listing to port could have suggested that happening. Stellar Daisy was originally built in 1993 and might be considered as a candidate for the type of fatigue damage not uncommon in ore carriers of a similar vintage were it not for the fact that the ship did not begin life as a bulk carrier. It was built as a tanker and by Mitsubishi Nagasaki in Japan but fell foul of the accelerated phase out of single hull tankers and was sold to its present owners Polaris Shipping for conversion to a VLOC at the end of 2006. Unlike some of the more rapid conversions of tankers into VLOCs that were carried at the time, that of Stellar Daisy took around two years. Ordinarily a conversion would add several years to the life of a vessel but there were a number of questions raised at the time about potential problems with such conversions. These centred on concerns over hull strength and the ability of the ship to handle the large loadings imposed on the bottom plating by ore cargoes. While the overall cargo weight would be much the same as when trading as a tanker, the much greater density of ore cargoes meant that this would be concentrated over a smaller area of the vessel. This issue was supposed to have been overcome by strengthening the tank tops both to accommodate the extra loading and as a precaution against grab damage. ShipInsight’s initial view that the conversion was a factor in the ship’s loss has been made firmer by later reports that another converted VLCC, Stellar Unicorn (converted 2012/13) of the same vintage and belonging to the same owner made an unscheduled stop in Cape Town while the search for Stellar Daisy survivors was continuing. The owner has since confirmed that a 15cm crack on the outer hull of no.1 starboard void tank was found and repaired. A large amount of criticism has been levelled at the owner in online blogs with regards to its safety policy and procedures. It is impossible for ShipInsight to comment on those criticisms but Polaris has been posting constant updates on the issue on its website. The last (as this issue went to press) detailing an immediate inspection system had been put in place. The statement says Polaris Shipping is fully committed to ensuring the safety of its VLOC converted fleet and their crews following the loss of the Stellar Daisy and have embarked on a systematic fleet structural survey program in consultation with Class KR and Lloyds Register as independent consultants. Class KR has drafted structural inspection guidelines for all of the vessels, which the managers and the crew have immediately implemented on board while at sea. All findings are reported to class. For those vessels which pass the initial on board inspection, as each vessel arrives at its earliest load or discharge port, she is being subjected to special survey by a team consisting of three dedicated senior superintendents from Polaris Shipping, three Korean Register Classification surveyors from the Dry Cargo Ship Technical Team and Survey Team and two engineers from Tae-Yang, a specialist steel strength gauging company. In addition, Polaris Shipping has engaged the services of Lloyds Register who have committed three Technical Advisers to inspect each vessel in turn and advise on structural strength and design issues. These initial condition surveys at the load and discharge ports will be followed by further in depth survey and analysis of each vessel, the results of which will be reported to Class for verification of hull strength in consultation with Lloyds Register. Any nonconformities, if discovered, will be rectified according to a hull strengthening plan approved by Class KR in consultation with Lloyds Register. Since the inspections are to take place at the first port of call for each vessel, there would seem to be little more that the owner and manager can do at the present time. What is of interest is how events in the now quite distant pass may have contributed to the loss of the ship and most of its crew. The cause of so many VLCC being converted to VLOC has its roots in the Exxon Valdez grounding and pollution in March 1989. As a consequence of that incident a whole raft of new measures were introduced in to bill that was eventually to be enacted as OPA 90. The bill itself was introduced in the same month as the Exxon Valdez incident. The amendments required a gradual phase out of single hull tankers beginning in 1995 and rolling through to 2010 depending upon the ship’s age. For its part the IMO was a little slower but in 1992 introduced amendments to MARPOL that came into effect the following year and which also set out a gradual phase out of single hull tankers which end in 2015. The timing of the IMO rules is significant because it came after the building contract for Stellar Daisy in its earlier incarnation as the VLCC Sunrise III would have been concluded. At the time the order was made and significant sums of money committed, the original owner would not have been aware that its investment was soon to be jeopardised. While an initial life of 25 years may have been envisaged that would have seen the ship due for retirement in 2018, its earlier disposal by around three years may not have been so disastrous. However, two more tanker incidents, Erika in 1999 and Prestige in 2002 were to have a major effect on the life of the ship that would have put the original owner in an even worse position and which might just be considered as the flapping of the butterfly’s wings that lead to the tornado of its eventual demise. Erika was a veteran tanker of almost 25 years when it suffered fatigue failure and went down in the Bay of Biscay. It was also a ship built at a time when fierce competition amongst classification societies was resulting in over-optimised designs. When the Prestige ran into trouble three years later in the same area it was 26 years old. The pollution that eventually occurred would probably never had happened but for the refusal of the Spanish and French authorities to allow the vessel to enter a port of refuge. The loss of the two ships caused the EU to press the IMO for an acceleration of the phase out of single hull tankers and that was quickly agreed upon by 2005 leaving owners of affected vessels facing a heavy financial hit and the loss of five years’ worth of earnings. For some the answer was to sell the vessels for conversion. Many were to become FPSOs, some converted into VLOCs and a smaller number even becoming semi-submersible heavy lift ships. At the time the wisdom of the phase out being accelerated was questioned. The Erika and Prestige were clearly elderly tankers with what some would say was a questionable maintenance record although at least one of the incidents could have been so easily avoided. Many of the ships affected by the phase out did not fall into this category and as was argued then, a more rigorous survey and inspection programme would have seen them safely through to a more normal retirement. Many will argue that as there has been no cases of major pollution incidents involving double hull tankers, the decision for the accelerated phase out of single hull ships was the right one. Others would say that the accident rate for tankers was on a steep downhill trend well before the phase out and while double hulls may be desirable, staying with the initial timetable would not have been so much riskier. It is of course an argument that cannot be proven although after Prestige, the only main pollution incident involving a single hull tanker was the Hebei Spirit in 2007. In that incident, the ship was at anchor and was hit by a barge that had broken free from its moorings in a storm. The damage cause could easily have caused a pollution if the ship had been a double-hulled vessel. Unless the world is very fortunate, there will eventually be a pollution incident involving a double-hull tanker and doubtless more knee jerk reaction. It would be ironic if the Stellar Daisy’s demise is officially attributed to fatigue or other reason connected to its conversion to a different ship type. If it is, then this will once again be a case of the consequences of hasty regulation not being fully thought through. Hopefully the action being taken by Polaris will prevent any further incidents with its fleet of converted vessels and similar action by the owners of other conversions should also be underway. What shouldn’t be forgotten is that not all conversions of single hulled tankers involved VLCCs, many smaller vessel types were also converted to bulkers. They too should be given some special attention just in case.
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