Introduction

The Vasa was built as a warship in Sweden between 1626 and 1628. The ship was ordered by the King of Sweden who demanded the strongest warship ever built. Even during the construction phase the King ordered additional ornaments and cannons. The extra demands required the ship to be lengthened and even an extra deck was constructed to make her the most powerful armed vessel at that time. At August 10, 1628, the ship started her maiden voyage but due to the added weight caused by the demands of the King, the Vasa was highly unstable. When the breeze filled the sails she capsized, 1400 meters from the quay where the spectators looked in horror how she sank. Multiple causes played a role. The original construction started with a Dutch builder who died during the process. Those who were given the task to finish the project could not withstand the extra demands of the King. Knowledge on stability was poor. The stricken ship was lifted in the 60’s of last century and is displayed at the Vasa Museet in Stockholm. An impressive sight, recommendable to read more about her story and see it in Stockholm when you have the opportunity.

Almost 400 years later. Our knowledge of ships, stability, forces, and strengths have grown over the years. People learned that even an unsinkable ship like the Titanic could sink. To make sure all this knowledge is used in a proper way the International Maritime Organization (IMO), was established following agreement at a UN conference held in Geneva in 1948. This United Nations specialized agency with responsibility for the safety and security of shipping and the prevention of marine and atmospheric pollution by ships first task was to adopt a new version of the International Convention for the Safety of Life at Sea (SOLAS). It is the most important of all treaties dealing with maritime safety. It came into force in 1960 and has been amended and changed over the years.

In 1970 MSC was founded. MSC stands for Mediterranean Shipping Company, and is a global business engaged in the shipping and logistics sector. It is headquartered in Geneva. MSC is a privately-owned organisation driven by the Aponte family. It started as a one ship company and has grown to a fleet of 520 vessels and more than 70,000 staff. It is an example of a company being able to grow and adapt to changes caused by for example economic headwinds, natural disasters, or operational demands. In the last decade they had ordered the then latest generation of containerships, bigger and larger than ever, capable to bring more loads from the East to the West, more efficient with less costs and lesser environmental impact. In 2007 MSC had lost one of her older generation vessels, the container vessel MSC Napoli due to structural failure during a storm in the English Channel. It took almost three years to salvage the cargo and break up the vessel.

The MSC Zoe incident investigation

In the night of January 1, 2019 one of these latest generation MSC vessels, the ultra large container carrier MSC Zoe lost over 3200 ton of her cargo at sea, carried in 342 containers. It became an environmental disaster and classified as a very serious marine casualty. A very serious marine casualty means loss of a ship, or a death or severe damage to the environment as defined in the Casualty Investigation Code of the International Maritime Organization (IMO) and European Union Directive 2009/18/EC.

It triggered an investigation by the flag state authority Panama (the country where the ship is registered) and the authorities of affected coastal states Germany and The Netherlands. The incident investigation is aimed at finding the causal factors and is conducted with the objective to prevent marine casualties in the future. Marine safety investigations should therefore be seen as a means of identifying not only immediate causal factors but also failures that may present in the whole chain of responsibility.
Investigation is based on fact finding, interviewing and analyses of all available material. For analyzing incidents many tools are available which support an investigator to structure findings. It is up to the investigation body and the team which analyzing tool they select. As an example, a simple way of conducting the analyses is asking the WHY. Like a small child can endlessly ask why, the investigator should apply this at least several times when he is digging deeper in search of causal factors. After the initial what happened, the WHY questions come up. Below figure is the five step approach, displayed in the investigation manual (p.127) available at the Maritime Accident Investigators International Forum website.


The investigator(s) start at the casualty event and work there way to the chain of events and link these to possible failure mechanisms, human actions, operational and organizational factors. In the case of MSC Zoe, the Casualty Event, the WHAT is described as the loss of containers overboard. Working their way up they come to the questions of WHY. The report is clear about the WHY’s. Due to the high stability of the vessel it was rolling within 15 seconds from starboard to port and vice versa heeling around 15 degrees which caused stresses to the lashings. See the investigation reports for all the details (reports available at: https://www.onderzoeksraad.nl/en/page/13223/safe-container-transport-north-of-the-wadden-islands.-lessons-learned).

WHY such a high stability?

In the report it is described how the stability is calculated. For that purpose, the vessel is equipped with a loading and lashing computer. At least two, one in the deck office and one on the bridge. The investigators were only shown the one in the deck office. As the investigators came on board a few days after the incident it was not sure if the settings were the same as they were a few days before during the incident. But the loading computer has the possibility for simulations. The investigators found that you can switch from Unrestricted Area to Asia-Europe and that this led to different calculations. They also found some red boxes in the Asia-Europe setting, indications meaning that loads exceeded limits. It is not further elaborated in the investigation report what this selection of area really means. WHY would you select from one area to the other?
To answer that question, we must go back as early as the years 2009/2010. We had faced an economic downturn and the world was just showing positive figures on economic growth. Demand of goods started to rise again and so did the demand on the logistic chain. It led to a demand from operators to look at the maximum capacity of containers on their ships. They turned to the classification authority Germanischer Lloyd (GL). This organizations classifies ships based on SOLAS and own regulations. With an inspection regime they check the vessels on a regular basis for their compliance to safety & environmental regulations. Classification authorities can work on behalf of flag states, most flag states have delegated the inspection regime to the classification authorities.
Based on the container operators’ requests, and after research based on vessel voyages, a new class notation was introduced by the classification authority. The LC/RSCS, meaning the Loading Computer/Route Specific Container Stowage. With this class notation, operators can increase the container height on deck, also on the outer rows, and have additional weight in the individual containers. The loading computer will calculate the lashing arrangement needed to apply to the stacked containers. See below picture to identify what the new rule means. The picture displays as an example Bay 46, with on the left side the application of the old rules and on the right side the application of the new rules. The difference in weights and heights add to an increase of 19% of stackload when selecting the Asia-Europe trade, compared with unrestricted trade.

 

Stackload Asia-Europe trade

As we can see in the picture (source; DNV GL Container ship Update 1/2014), the center of gravity has moved upwards as additional weight is accepted. In 2013 Germanischer Lloyd (GL) merged with Det Norske Veritas (DNV). The class society now named DNV GL, describes this notation as follows.

“By introducing LC/RSCS, the safety margin related to the load assumptions has been lowered a little, but this has been compensated by increasing the safety level at another point – we introduced the mandatory requirement that the ships had to be fitted with an approved lashing computer system.” (DNVGL – Container Ship Update 1/2014).

In other words, it is less safe, but that is compensated with the loading/lashing computer. However, in the report we find a statement by the investigating authority that the calculations used in the software are not transparent. The report also mentioned that most calculations as found in the cargo securing manual are not applicable to this size of ship. The LC/RSCS code is developed by industry in the period before the new class of container vessels was designed and built. Without any further research the RSCS code is applied to the new generation of vessels to accommodate the market requirements for increased transport of large volumes of cargo with lower environmental impact and less costs.

Consequences

It can be expected that the Asia-Europe mode was used as it is the route the vessel sailed, and it gives the opportunity to have more weight (19% more) in the stacks. An overview of loaded containers and weights at departure from Sines, Portugal will have the answer which mode was used and what indications of red boxes there really were. As far as I understand from the report this could not be investigated as MSC suggests that data shown was not correct and cannot be retrieved.
Nevertheless, you can conclude that with the class notation LC/RSCS additional weight is allowed in the outer stacks. Increase of weight will increase the load on the lashing material. MSC states that they allow incidental 120% stress loads on lashing material, meaning they allow to pass the official Safe Working Load with 20%. With lowering the individual margins, the overall margin is considerable less then can be expected. The crew and captain on board would not have a clue on the exact forces at the lashing arrangements. The red box indicators displayed at the loading computer may have been an indicator, although those stacks were not lost overboard as concluded in the report.

Conclusion

Learning from incidents is the objective to prevent marine casualties in the future. Being it lost ships, death, or environmental damages. What did we learn in 400 years? There will be no official museum for MSC Zoe lost containers, like we have a museum for the vessel Vasa. Both shipping incidents were watched when they unfolded and both find their origin in stability, although the Vasa had almost none, the MSC Zoe had too much of it. Is it safe to say that the King’s demand to have a bigger ship than the enemy can be translated to nowadays transport? The container lines are in a continuous demand to sail as economic as possible. The answer is growing bigger and be more efficient then the competitor. Losing containers (and sometimes whole ships like the MSC Napoli) is not wanted, but part of the ‘game’.
No museum for MSC Zoe, but for years to come you can find traces of the incident at the beaches and dunes in the World Heritage Site ‘Waddenzee’ and the German Bight up to Denmark. Especially the estimated 24 million polystyrene beads are not easily detected and will be taken up by the environment and eaten by birds and fish. In a press release statement MSC noted;

“Safety at sea and the protection of the marine environment are top priorities for MSC. We note that the MSC ZOE response operation has uncovered an enormous amount of debris underwater from many different shipping activities and accidents dating back to long before container shipping began.”

author: Thom Koning

Sources:

• IMO Resolution MSC.255 (84) Casualty Investigation Code
• IMO Resolution A.1075 (28) Guidelines to assist investigators in the implementation of the casualty investigation code
• Marine Accident International Investigators Forum – Investigation Manual 2014.
• Investigation report – Loss of containers overboard MSC Zoe, Panama Maritime Authority, Dutch Safety Board, Bundesstelle für       Seeunfalluntersuchung
• Container Ship Update 1-2014, DNVGL
• Container losses and Route Specific Container Stowage, Matthias Galle, Vice President DNV GL, presentation at International Union of Marine Insurance conference Berlin September 2015.
• Website www.MSC.com
• Website vasamuseet.se/en
• Website: https://www.hellenicshippingnews.com/loss-trends-larger-vessels-bring-bigger-losses/