Severe weather?
When researching the causes of container losses at sea that do not occur as a result of collisions, it is noticeable that severe weather conditions are often given as the reason. In fact, however, at least some of the losses occurred in weather conditions that do not actually fall into the category of severe weather. A recent case exemplifies the aforementioned proposition: wind speed 6 bft, wave height 5 m-6 m. Such wind speeds and wave heights usually encountered at sea are not to be classified as “severe weather conditions” for a 400m long and 60m wide container vessel.
In this respect, other causes seem to contribute to the losses, and the following questions arise:
- Are the previous assumptions, calculation models and methods of securing the containers sufficient?
- Do situations occur in practice that are not covered by theory?
- Are the small crews too often left alone with the issues in the face of high economic and organisational pressure?
- How much of the responsibility lies with the shipping companies, who urge their employed captains to maintain the schedules, sometimes contrary to sound nautical judgement?
This article aims to present the facts as clearly as possible.
1
Why are there no international regulations
for securing containers on board container ships that are based on state-of-the-art technology?
As can be seen, for example, from the investigation report (publicly available) into the MSC Zoe case, the cargo-securing measures must comply with the IMO Code of Safe Practice for Cargo Stowage and Securing (CSS Code), edition 2011.
The chapters of the CSS Code describing the fundamentals state that a vessel must be equipped in such a way that the cargo can be safely stowed and secured in order to weather all conditions which may be encountered during the voyage (Chapter 3 - Standardised Stowage and Securing System). (The author refers back to this point in Question 6).
In the further chapters in the CSS Code, it is stated that the Captain is responsible for the proper securing of the cargo. The methods in Annex 13 are provided as tools to perform the necessary calculations.
Annex 13 clearly states that these methods are based on a vessel of 100m in length. Corrective methods are provided for vessels of other sizes. However, it is also stated that a correction formula can be applied only to vessels of up to 300m in length.
The fact that there are no adequate regulations presented in the 2011 CSS Code (the most up-to-date edition) is incomprehensible, especially when one considers that, for example, a large Danish shipping line had the first 400m container vessel constructed as early as 2006, accompanied by considerable media attention.
2
Are cargo securing manuals or calculation programmes
of the classification societies based on data that is not in line with current practice?
Using the example of the MSC Zoe, the published accident investigation report states that the calculations of the cargo securing calculator, based on the vessel’s cargo securing manual, assume a GM ≤ 2.08m.
When requesting the vessel’s command during loading operations to advise the vessel’s GM at the port of departure or the GM to be expected on long voyages (the long overseas routes), figures of between 6m and 10m will often be given. In some cases, the figures will be even higher. In the case of the MSC Zoe, the GM was 10.23 m; in the case of loading operations on other large container ships, the author has been provided with GM values of up to 18.5 m.
Such discrepancies are extremely problematic! This is because the acceleration values to be expected are markedly increased by high GM values.
Only in the case of heavy-lift loading operations with qualified personnel, for example a supercargo or a heavy-lift surveyor, is there any possibility at all that such circumstances will be noticed and the cargo-securing measures adapted, if necessary, or the loading operations even aborted.
It could be argued that the vessel’s command, or rather the ship planners, could plan the cargo in such a way as to take the GM of the ship into account. This objection may be justified in theory, but it does not correspond to common practice. Ultimately, in order to increase the weight towards the top with ballast water, the vessel would need “wing tanks”. However, in most cases, modern ships are not equipped with these tanks. It would also be possible to increase the weight of the cargo towards the top. It should be noted here that one increasingly receives the impression that some planners do not understand their ships well enough! But it is also impractical to assume that the planners are able to position the cargo anywhere on the vessel. In some ports, this would also mean additional containers which would have to be restowed, which the ports generally try to avoid in an effort to be cost-effective.
Issues that exacerbate such problems are slot charter models and, of course, container bays that are stowed according to the port of destination and generally according to the principle of “last in - first out”.
Thus, it seems easier to adapt the structure, manner of loading and cargo securing to the changing circumstances than vice versa.
3
Why is there such a large discrepancy between
regulatory requirements?
Looking at the CSS Code and the CTU Code, there are a number of differences when considering the same issues. A simple example of this is the different assessment of friction coefficients. Further aspects of this issue will be discussed in Section 4.3.
It is important to consider that the classification societies calculate the acceleration parameters on a different basis than the other parties in the international transportation industry.
It is to be noted that classification societies are neither fully
commercially-independent nor non- partisan bodies. They are ultimately service-providing market participants. In order to win a contract, they have to offer both their service itself and their requirements for compliance with regulatory requirements within an attractive cost framework.
The Report • June 2021 • Issue 96 | 55
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