SAFE SHIPPING ON THE BALTIC SEA 24-25 April 2009

Gdańsk, Poland

Organising Committee:

��Dr Jan Jankowski, Polish Register of Shipping � Chairman of the Committee

��Dr Andrzej Królikowski, Maritime Office in Gdynia � Member

��Mr Paweł Szynkaruk, Polish Shipowners� Association � Member

��Dr Adolf Wysocki, Polish Shipowners� Association � Member

Honorary Committee:

��Mr Johan Franson, Swedish Maritime Administration

��Mr Markku Mylly, Finnish Maritime Administration

��Mr Andreas Nordseth, Danish Maritime Authority

��Mr Evaldas Zacharevičius, Lithuanian Maritime Safety Administration

The Symposium is organized under the auspices of the Polish Ministry of Infrastructure with the attendance of Ms Anna Wypych-Namiotko, Undersecretary of State.

CONTENTS

Overview by Jan Jankowski, Polish Register of Shipping ................................................... 5 Foreword by Anna Wypych-Namiotko, Undersecretary of State,

Ministry of Infrastructure, Poland .......................... 7

Foreword by Paweł Szynkaruk, President of Polish Shipowners� Association .................... 9

Session I

Weather Conditions and Safe Navigation in the Baltic Sea Markku Mylly, Finnish Maritime Administration ..................................................................... 13

Safe Ship Operation Wojciech Sobkowiak, Polferries, Poland .............................................................................. 19

Session II

The New German Strategy to Deal with Maritime Emergencies at Sea and on the Coast Michael Akkermann, Central Command for Maritime Emergencies, Germany ..................... 23

Handling Risks to Maritime Oil Transportation in the Baltic Sea � a Danish Perspective Per Sønderstrup, Danish Maritime Authority ........................................................................ 27

Session III

The Need for Coordinating Shipping and Traffic Control in the Baltic Sea Area Johan Franson, Swedish Maritime Administration ................................................................ 33

Coordinating Shipping and Traffic Control on the Baltic Sea Hans-Heinrich Callsen-Bracker, Ministry of Transport, Building and Urban Affairs, Germany ................................................................................... 37

Session IV

A Technically Safe Ship: View from the Lithuanian Perspective Povilas Juozapavičius, Mindaugas Česnauskis, Lithuanian Maritime Safety Administration ........ 43

Survivability of Ro-Ro Ships in Damage Condition Maciej Pawłowski, Gdansk University of Technology; Jan Jankowski, Polish Register of Shipping; Andrzej Laskowski, Polish Register of Shipping ...................................................................... 51

Annex ................................................................................................................................... 63

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OVERVIEW

Shipping in the Baltic Sea Region is specific by nature. The Baltic Sea is a small and enclosed water basin featuring characteristic, dangerous weather conditions, hazardous particularly for some ship types. The specificity of shipping also include heavy traffic of people and goods between the well-developed countries around the Baltic.

Substantial catastrophes on the Baltic confirm this thesis. The risk of possible catastrophes generates the need for protection against oil spills, which may cause extensive damage to the marine environment and to coastal regions.

IMO Conventions do not always account for the specific nature of the Baltic Sea. This means that development of additional requirements is required. A good example of the above is the Stockholm Conference, which prepared more stringent requirements for ferries operating on the Baltic Sea than those stipulated by international conventions.

The purpose of the Symposium is to provide a discussion forum for maritime administrations and shipowners to identify and emphasize problems of Baltic shipping. Discussion will follow several introductory papers addressing:

�� Specific weather conditions on the Baltic Sea; �� A technically safe ship; �� Safe ship operation; �� Coordinating shipping and traffic control on the Baltic Sea; �� Oil spills protection.

Jan Jankowski

Polish Register of Shipping

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Ladies and Gentlemen,

As we all know maritime transport plays a special role in world economy, particularly in the economy of the European Union. It is not only a question of its share in international trade but also an ecological issue. Statistical data indicate that this form of transport has the least adverse impact on the environment and is a minor source of environmental pollution as compared to land-based activity.

The Baltic Sea is one of the most traffic congested water basins not only in Europe but also worldwide being at the same time a very sensitive area generally recognised as a special region. Baltic shipping is classified by the European Union as short sea shipping. It is listed on the priority list of European Union shipping policy as the alternative for land based transport.

The Baltic Sea is a relatively small water basin featuring dense vessel traffic, and exposure to risk due to the ship draught of tankers and ships carrying hazardous cargo. Minimising the risk of safe shipping on the Baltic may involve regulating ship traffic by defining safe traffic separation schemes (PSS), deep water routes (DW routes) and systems restricting traffic. A major factor in regulating traffic on the Baltic is the development of Vessel Traffic Monitoring and Information Systems (VTMIS) in particular countries around the Baltic followed by integration of the systems on the regional level.

Protection of the natural marine environment against pollution is another aspect of no lesser importance. The Baltic Sea can be described as a special area in these terms as the water exchange in the basin is exceptionally slow. Therefore, the only effective measure of protecting the natural environment is prevention by adopting pollution prevention measures that cover the entire spectrum from the air quality to microscopic life forms. Successful improvement in terms of safe shipping and protection of the Baltic Sea can only be achieved by effective implementation of internationally expressed commitments dealing initially with territorial waters of particular states.

I do hope that today�s Symposium becomes the first of a series of meetings of parties representing the Baltic maritime sector that established a forum for long-standing cooperation for discussing commitments on the regional and EU level.

Thanking Dr Jankowski for the invitation to participate in this initiative I wish you fruitful discussions on assurance of safety and the protection of the marine environments of our Baltic Sea.

Anna Wypych Namiotko

Undersecretary of State, Ministry of Infrastructure, Poland

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Dear Sirs,

It is a great honour and pleasure, that on behalf of Polish Shipowners� Association I have the opportunity to welcome all the participants of the Symposium on Safe Shipping on the Baltic Sea here, at the premises of Maritime Museum in Gdańsk.

The Baltic Sea is a very sensitive area from the ecological point of view, where exchange of water is very slow and lasts even 30 years. On the other hand the number of vessels that cross this sea is growing every year. At any given time 2000 vessels navigate there. Many of them are tankers, transporting crude oil from the ports of Russia to the westbound destinations. Any serious sea accident of just one of them would have unimaginably adverse consequences for the entire region persisting for many years.

The Baltic countries are aware of risks that the shipping activity may create and this is the main reason why they jointly work for the protection of the Baltic Sea. In 1974 the Baltic states signed the Helsinki Convention on the Protection of the Marine Environment of the Baltic Sea Area and Baltic Marine Environment Protection Commission, the governing body of this Convention, also known as HELCOM was created. HELCOM�s most ambitious project in recent years is the so-called Baltic Sea Action Plan. The program is a consequence of adopting an EU directive on the strategy concerning the marine environment.

At this point I have to recall the role of the International Maritime Organization that is responsible for the main activity towards the protection of the marine environment in the Baltic Sea, as well as towards other seas and oceans of our planet. One of the pillars of IMO�s legislature is MARPOL Convention.

Amendment VI of this act established the Baltic Sea as a Sulphur Oxide Emission Control Area and that means that since May 2006 all vessels entering the Baltic must use fuel with low content of sulphur.

Also other amendments of Marpol Convention have the substantial importance for the high quality of environment in the Baltic Sea, i.e. as Amendment IV on the Prevention of Pollution by Sewage from Ships and Amendment V on the Prevention of Pollution by Garbage from Ships. Through the regulations created by IMO, since 2005 runs the process of elimination of single-hull tankers from world-wide shipping. This process will be completed � with some exceptions � by next year.

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International Maritime Organisation gained European Union as a powerful ally in the joint activity for safe shipping and marine environment protection. More and more acts and regulations of IMO are being adopted by the EU agendas and these new regulations are made in close cooperation of these two organisations.

The necessity of this cooperation is also mentioned in the UE strategy on the maritime policy and transport to the year 2018. For example, European Commission proposes the common ground for creating cohesive legislature in the scope of the responsibilty for losses related to marine catastrophes and oil spills. The ambitious plan of Brussels � or rather just a wish - assumes that all UE countries will reach �the white list� of Paris Memorandum of Understanding by 2012. The other goal is the signing by all members of UE of the most important Conventions that regard maritime transport. In the field of steady supervision of shipping, the EC proposes to create an integrated system of managing information, using the systems; AIS, LRIT, SafeSeaNet, CleanSeaNet, Galileo or GMES.

A very important event of the last months was the adoption of Maritime Safety Package III, so-called �Erika III� by the European Parliament. This is the direct continuation of packages: �Erika I� and �Erika II�. The third package regulates, among others, the responsibility of the flag state and the range of inspections in UE ports, creates rigorous regulations concerning the reception of endangered ships in the ports of refuge, enforces the duty to insure ships� passengers, raises safety standards of the vessels, putting the worst of them on �the black list�.

There was not only applause during the compiling of the package �Erika III�. Some UE countries opposed the shifting of many competencies from the level of state administration to the European Union. Some shipowners protested against the full third party liability for ecological catastrophes. Anyway, after a fervent but also constructive discussion, the Third Maritime Safety Package was adopted by the European Parliament at the beginning of March this year.

It is satisfactory for the whole maritime society that these two organisations: IMO and Europaen Union look arm in arm for the best solutions in the sphere of safe shipping and protection of the marine environment.

This activity is fully supported by the European Community Shipowners� Associations (ECSA), of which Polish Shipowners� Association is also a member. The ECSA is very helpful in the process of making decisions by these organisations as a voice of shipowners and practicians who are aware of the effect of the new rules on the level of common life.

The ECSA took on an important role in elaborating Maritime Safety Package III and particularly welcomed the proposal of targeting sub-standard vessels and new inspection regime based on the concrete risks connected with these ships. We also supported the establishment of the rules relating to places of refuge for ships in distress.

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As far as the safety of shipping and protection of the marine environment are concerned ECSA closely cooperates with European Maritime Safety Agency (EMSA) for example in the creation of the project called European Long Range Identification and Tracking of Ships (LRIT).

Annex VI to MARPOL Convention and the new idea of even more stringent standards on the sulphur content in ships� fuel is the hot topic during the discussions within ECSA. We support lower sulphur and nitrogen emmisions, but as shipowners we also point out the negative conequences of using new kinds of fuels: additional costs, potential danger of shifting the transport routes from the sea to the land, periodic shortage of fuel supply, technical problems with the engines, etc.

Finally, ECSA and its members also discuss solutions for reduction of CO2 emission. While shipping is responsible for only 2-4 percent of carbon emission worldwide, shipowners committed themselves to make some improvements in the industry. We take into account various ideas, for example, reduction of ship speed, alternative fuels, increased efficiency of engines, optimisation of hull and propeller design, etc.

The activity for safety shipping and marine environment protection runs on various levels. The initiative to organize the Symposium on safe shipping on the Baltic Sea last year was the expression of the will to engage all the Baltic states in this action. In the 15th anniversary of the tragedy of �Jan Heweliusz� the participiants of the symposium discussed most of all passangers� safety on ferries and ro-ro vessels. The idea of the international symposium ended positively, and that�s why we meet again.

The main subject of today�s conference is safe shipping in the Baltic Sea. I�m sure that during the meeting we will have a chance to hear very interesting presentations that will help us in the fruitfull panel discussion.

I wish all the participants of our symposium much intellectual pleasure and I hope that the ideas and subjects we may work out today will serve maritime companies in their daily practice.

Paweł Szynkaruk

President of Polish Shipowners� Association

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Weather Conditions and Safe Navigation in the Baltic Sea Markku Mylly

Finnish Maritime Administration, Finland Markku.Mylly@fma.fi

The Baltic Sea and its environs The Baltic Sea is a small and shallow sea that is connected with the North Sea through the narrow and equally shallow Danish Sounds. The water exchange in the Baltic Sea is very slow; a complete exchange is estimated to take about thirty years. The mean depth of the Baltic is 55 metres, the deepest spot is 450 metres and the area of the Baltic is 415,000 km². The salinity in parts per thousand is less than 24.6; that means that the Baltic is not an actual sea but a brackish water basin. Each year the Baltic Sea is covered by sea ice, usually for about seven months of the year. On an average, half of the area of the Baltic Sea is covered by ice, in mild winters perhaps only about a quarter. The annual variations can be relatively large. Normally freezing starts in October-November. Ice break-up starts in April, and by early June the Baltic Sea is usually free of ice.

Baltic Sea area parameters If Norway, the northern parts of Germany and the western parts of Russia are included, the Baltic Sea area comprises

� 46% of the total area of the European Union � 23% of the population of the Union � 16% of the GDP of the Union.

� The population amounted to roughly 103 million, the combined GDP, excluding Russia, to 1,609 billion euros in 2004.

� Although integrating, the area is heterogeneous and characterized by polarities. � It is an area of intense economic growth, at least measured on a European scale. � In the years 1995-2004 the combined GDP of the area grew by 42.4% (average

annual growth about 4%). � In 9 countries of 10, the economic growth exceeds the EU average.

The HELCOM Convention and the Helsinki Commission

The Convention on the Protection of the Marine Environment of the Baltic Sea Area (HELCOM Convention) was signed by the Baltic Sea rim states as early as 1974. The Helsinki Commission has been active since 1980 in preventing pollution of the Baltic Sea. The Commission is an intergovernmental organisation comprising all signatories of the Helsinki Convention, including EU, and various intergovernmental organisations and voluntary civic organisations take part in the work of the Commission as observers.

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The HELCOM Convention entails responsibility to reduce the environmental load from all discharge and emission sources to protect the marine environment and preserve the diversity of species. The main task of the Helsinki Commission is to monitor compliance with the Convention. The parties to the Convention adopt recommendations by acclamation and reports on the degree of compliance with them are filed on a regular basis.

Transport in the Baltic Sea According to the Baltic Maritime Outlook 2006, the increase in maritime transports is expected to be notably higher in the Baltic Sea than in the rest of Europe. The transport performance is expected to grow by 45% over the period 2003 to 2010 as the average growth in Europe is a mere 32%. The corresponding growth figures from 2003 to 2020 are predicted to be 93% for the Baltic Sea and 66% for the whole of Europe. In 2003, maritime transports in the Baltic Sea totalled 730 million tonnes and they are predicted to grow by 470 million tonnes to a total of 1,200 million tonnes by 2020.

Winter and ice conditions in the Baltic Sea Every winter the northern part of the Baltic Sea freezes up, and during severe winters the Baltic may freeze over in its entirety. The significance of maritime transports and the difficult conditions prevailing in the Baltic Sea make specific demands on the functioning of the transport chain. For winter navigation to be safe and efficient there must be a good icebreaker fleet and high-quality, up-to-date weather forecasts and information on the ice conditions available. Ships requiring assistance must be suitable for navigation in ice. As traffic increases, the role of the ship�s crew is accentuated, whether the ship gets icebreaker assistance or not. Nowadays, many of the ships moving in the area are operated by crews which lack sufficient knowledge of navigation in ice. This increases the risk of accidents significantly.

Oil transports in the Gulf of Finland are continuously increasing Oil from Siberia to Western Europe In 2006 some 140 million tonnes of oil were transported through the Gulf of Finland. This is seven times the volume transported ten years ago. The share of Russian ports is 90 million tonnes, the share of Estonian ports 30 million tonnes, and the share of Finnish ports 20 million tonnes. The oil comes from the Siberian oil fields in Russia. This year Russia exports almost 350 million tonnes of the oil that it produces. More than a third of this volume is shipped through the Russian and Estonian terminals in the Gulf of Finland. The oil exported by Russia through the Gulf of Finland is destined for Western Europe. According to HELCOM statistics an average of ten fully-loaded tankers leave the Gulf of Finland every day. Several projects for the enlargement of existing terminals are under way. If all investments are realized, the annual volume of oil transports in the Gulf of Finland increases to 250 million tonnes by the year 2015. Even a more moderate development increases the volume of oil transports to at least 200 million tonnes over the same period.

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Russian oil terminal projects Primorsk is the most significant oil terminal in the Gulf of Finland. The final phase of the BPS pipeline to Primorsk was completed in spring 2006, which increased the annual capacity of the oil terminal to 65 million tonnes. There are still other developments under way in Primorsk, for instance a terminal for the unloading of oil transported by rail, a new pipeline for oil products, oil refineries and a terminal for the export of liquefied natural gas. The other oil terminals are smaller. The terminal owned by Lukoil in Vysock, which is specialized in the export of oil products, reached an annual capacity of 12 million tonnes in the summer of 2006. There are several terminals in the port of St. Petersburg; one of them equally specializes in the export of oil products. Nowadays, its annual capacity also amounts to 12 million tonnes. In Ust-Luga, Russia is forcefully developing a large cargo port. Both in Ust-Luga itself and the area east of it, several oil terminals are planned.

Estonian and Finnish oil terminals More than 20% of the oil transported from Russia is shipped through the Baltic countries. These transports largely consist of oil products. The export of crude oil through Baltic ports has decreased by two thirds since the opening of the terminal in Primorsk. Thus no Russian crude oil is shipped through the port of Ventspils today. Still, the volume of oil products shipped through the ports of Tallinn and Muuga amounts to as much as 30 million tonnes a year, and, when new terminals are completed in the port of Sillamäe, the oil shipments through Estonia will increase even more. The Finnish share of oil transports in the Gulf of Finland amounts to slightly more than 20 million tonnes. The major part of it is transported via the Porvoo refinery.

A large part of Russian oil is exported through the Gulf of Finland Of the 470 million tonnes of oil produced in 2005, Russia exported 250 million tonnes as crude oil and almost 100 million tonnes as oil products. Almost 300 million tonnes of oil and oil products were shipped abroad through Russian, Ukrainian and Baltic ports. In the near future, Russia will develop new oil transport routes, such as the pipelines planned for the Pacific Ocean and the Barents Sea. It does, however, seem that oil shipments will both continue and increase in the Gulf of Finland.

Vessel traffic in the Gulf of Finland The number and size of tankers has increased � but not at the expense of quality The port calls of oil tankers in the Gulf of Finland have doubled during the last three years. The increase in number has not, however, taken place at the expense of quality, as more and more tankers are relatively new and of a good standard. Thus, it is noteworthy that a study made in May 2004 shows that no single-hull tanker called at the ports of Sköldvik, Primorsk and Muuga anymore. A similar study made in 2001 showed that for instance 35% of the vessels calling at Muuga were still single-hull tankers. The fact that new tankers have been put into service is also illustrated by the figures for the average age of tankers: between 2001 and 2004 the average age of oil tankers calling at Muuga was reduced by five years and in Sköldvik by three years.

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During the last few years, there has not only been a remarkable improvement in the overall condition of tankers but also a significant increase in their size. The number of larger 75,000 to 100,000 DWT vessels has grown rapidly at the expense of smaller vessels. Crude oil is shipped by handy max type vessels from Baltic ports to the European and U.S. markets as the use of vessels of 150,00 DWT and over is restricted by the shallowness of the Danish Sounds. However, new vessel concepts enable vessels of up to 250,000 DWT to sail in the Baltic Sea.

Ulf Ryder, President and CEO of Stena Bulk has said in an interview in the newspaper Dagens Industri that Stena Bulk and the state-owned Russian shipping company Sovcomflot have published a letter of intent concerning a new B-MAX type of tanker for traffic in the Baltic Sea. The projected breadth of the tanker is 60 metres and the projected length 270�290 metres.

Safety enhancing actions International organisations: IMO � EU/EMSA The International Maritime Organisation, which was founded in 1948, comprises 167 member states. Owing to the international nature of shipping, matters relating to maritime safety and pollution prevention are decided in IMO, which makes the application of the provisions mandatory for all member states. Maritime safety may be divided into technical safety and operational safety. Technical safety comprises the structural safety of ships and the safety of their equipment. Most accidents are caused by erroneous actions or neglect by the ship�s crew. Technical malfunction is the cause of a mere fifth of the accidents. In April 2003 the IMO adopted an accelerated phase-out scheme for single hull tankers which means that these tankers will be phased-out by 2015. In October 2003 the European Union adopted a regulation on an immediate ban on transport of the heaviest types of oil in single hull tankers to and from EU ports. The ban is also in force in new member states. Furthermore, actions to enhance maritime safety and improve oil combating preparedness have been taken in the Gulf of Finland and in the rest of the Baltic Sea as well. In Annexes I, II and V to the MARPOL Convention, IMO has classified the Baltic Sea as a particularly sensitive sea area in which mandatory special actions to prevent pollution of the marine environment must be taken because of the oceanographic and ecological state of the sea and the density of vessel traffic. This means that the Baltic Sea has been given a higher status of protection than other sea areas. The European Union will continue to take steps to safeguard maritime safety. The third maritime package introduced in late 2005 is still being processed within the EU. In the background there are the two first EU maritime safety packages, ERIKA I and ERIKA II. Through the latest maritime package, now under consideration, the EU is tightening its grip even more. The new package consists of seven legislative proposals by which the EU aims at greater efficiency in preventing maritime accidents and pollution of the marine environment.

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The first proposal, the flag state obligations directive, aims at intensifying the responsibility of the Member States in ensuring compliance with international rules and regulations of ships sailing under their flag. The purpose is also to tighten the rules according to which ships are registered under Member State flags and support the development towards the implementation of a single EU flag. The second proposal aims at a revision and clarification of the directive on port state control and ensuring unified inspections within EU. The aim is to ban sub-standard ships from European waters. Proposals to revise the directives on classification societies and vessel traffic monitoring have also been made. It is suggested that an independent quality system be set up to monitor the classification societies. The purpose of amending the directive on vessel traffic monitoring is to establish a clear and precise legal framework for places of refuge and to continue to develop the EU system for collection and exchange of data, SafeSeaNet, and make the Automatic Identification System mandatory also for fishing vessels over 15 metres long. Furthermore, the proposal takes into account the risks for shipping involved in the freezing of the sea, which is a significant point of view especially with respect to the Baltic Sea.

What should be done to reduce the risks involved in the transport of oil? The Gulf of Finland has so far � luckily � been spared huge oil disasters. But there is no room for complacency. The increase in traffic volumes has increased the probability of an oil disaster significantly. Nature in the area is particularly vulnerable and the prevailing conditions may be likened with Arctic conditions as a significant part of the sea area is covered by ice during long winter months. The Gulf of Finland is narrow and its coast is indented. This is why even a small oil spill in the sea would have serious direct implications for the people and nature of all three surrounding coastal states. Recent oil spill disasters in various parts of the world have launched international processes for the enhancement of maritime safety on a global scale. Thus, the Helsinki Commission has adopted several recommendations to improve maritime safety, for instance common winter navigation rules, which entered into force in 2004. Finland, Estonia and Russia launched a joint mandatory reporting system for ships, GOFREP, in the Gulf of Finland in July 2004. The need for such a system was assessed by the Technical Research Center of Finland. A risk analysis showed that up to 80% of the statistically conceivable collisions could be avoided by creating such a system in the international waters of the Gulf. However, the ship reporting system is only one of the risk management methods for the improvement of maritime safety. A comprehensive risk assessment analysis comprising the whole Baltic Sea area should be carried out. It should result in a number of proposals for further action. Such proposals could form the risk management methods that should be taken into use for the improvement of safety.

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In my view, the risk management methods should involve the following: 1. Traffic monitoring/VTS should comprise the whole Baltic Sea 2. Mandatory routeing plans / large tankers � mandatory reporting to VTS centre 3. Comprehensive routeing system 4. Increased cooperation between icebreaker managements 5. Exploitation of technological innovations in winter navigation 6. Securing of crew competence, especially in winter navigation 7. Intensified oil combating preparedness and environmental monitoring 8. Reduction of ship-generated discharges into the sea � technological solutions

� fee systems with incentive effects should be created 9. Comprehensive hydrographical surveys of the Baltic Sea 10. Better use of technological innovations in navigation 11. Better use of the deep-sea pilotage system

Maritime transport is on the increase and the Baltic Sea area is experiencing the most significant growth in this field in the whole world. The enhancement of maritime safety in our waters still requires continuous forceful action if we want to ensure safe sea routes for shipping and leave a cleaner Baltic Sea to future generations.

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Safe Ship Operation

Wojciech Sobkowiak Master of ferry �Scandinavia�, Poland

wojso2@wp.pl

Abstract The goal of the presentation is to answer the question: �Is the operation of the ship on the Baltic Sea safe?� The problem will be presented from a practical point of view.

Keywords: Safe ship operation at Baltic Sea from practical point of view

1. Assessment of certain aspects of sailing on the Baltic Sea Although The Baltic Sea is a much smaller area in comparison with The North Sea, The Mediterranean and the like, average weather conditions (i.e. periods and percentage of storms, sea state, restricted visibility etc.) are very similar to those of the above and well known to most users of the Baltic. However, it is important to emphasize one weather-related factor, namely very steep and short waves that ships can encounter here. Other major difficulties that we have to face include: 1. Fishing vessels and fishing nets.

During allowable periods, within the Polish Exclusive Economical Zone and north of it up to MOU Petrobaltic there is a great number of fishing vessels and large areas of fishing nets forcing us to change course and lengthen our route by up to 20 Nm.

2. Irregular traffic of coasters bound for and from the Baltic States in W-E direction (potentially also disturbed by large areas with fishing nets).

3. Question of disordered traffic flow in the southern part of Baltic Sea reported by Baltic pilots and masters of ships sailing to and from the ports in the Gulf of Gdańsk. There is no structured traffic scheme. The common incidence of head-on close encounters in the confined space of navigable waters could easily cause collisions and groundings. Vessels, with a considerable draft in relation to available depth of water, attempt to cross the shallow banks, often in rough sea conditions, clearly not taking into account all factors influencing safe keel clearance and thus risking grounding. High activity of fishing vessels and large areas of fishing nets create additional difficulties.

2. Actions taken by the governments of the Baltic coastal states The Master of a vessel that is ready to sail is well-equipped with different means of support, such as: �� International conventions (SOLAS, IMO) as well as flag & state and local rules &

regulations, �� The owner�s surveillance (ISM, DSS, SAR-Cooperation etc.), �� Obligatory systems provided by land i.e. SRS, VTS, AIS, which can provide

support in need,

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�� Voluntary system of Maritime Assistance Service (MAS), �� Areas of restricted traffic - DW Routes, TSSs and other special marks for safe

passage, �� Hydro-meteorogical support: current weather forecasts from VTS, coastal stations

as well as on the Internet (same with more details). Ships are therefore monitored along their whole route and can request and get immediate support if in need. The available support ranges from rescue of lives and environment protection measures to any kind of technical assistance.

3. Examples of the monitoring systems used in practice on land and on vessels

Ferry �Scandinavia� sailing between Gdańsk and Nynäshamn participates in the work of a monitoring system basing on ship and shore AIS stations and Vessel Traffic Services. I may present many examples of successful results of their activity. Some of them are mentioned below. 1. The south end of the Oland Island, Sweden. Stormy night, wind speed 26-30 m/s

from NW. Ferry �Scandinavia�, well sheltered, sailing at reduced speed, 4Nm from the land; Master's choice: changing the course by 180 deg with the intention to run up and down. Immediate call from Swedish Naval Control with the question: �Scandinavia�, why did you alter your course on reciprocal?� Explanation from the ship, attentive monitoring works.

2. Similar situation, M/F Scandinavia on her way to Nynäshamn, daytime, calm sea, heading north at full speed, must drop 15 minutes due to traffic in the harbour. With the Master's consent, the officer of watch slowly altered the ship�s course by 90 deg with the intension to return to the original course. Immediate call from Swedish Naval Control, the operator asking �Scandinavia, is there any serious reason for altering your course by 90 deg.?� Explanation from the ship - situation clear.

3. Ferry �Scandinavia� on her way to Nynäshamn, 0730 a.m. The ship receives the following message on the radar screen via AIS: �WRONG DATA: Your AIS course differs by 30 deg from your actual course� sent by ferry m/f Visby, heading for the same destination. Data correction performed.

4. August 2007, north of Gotland, ferry Scandinavia makes shelter and provides assistance to two Estonians who have been drifting for two days on a motor yacht with a broken engine, out of mobile phone coverage. The �Rescue Scarsende� lifeboat on her way for towing. Her AIS mark well seen on the ECDIS screen, the ferry's AIS mark showing the position on scene precisely. SAR action quick and effective.

5. The Swedish east coast, a VTS operator notices that a cargo vessel is heading directly towards rocks instead of using the TSS route. Together with the MRCC Goteborg�s operator on duty, after an emergency call and getting liaison with the ship in peril, directed the ship to safe waters at the very last moment by ordering a number of course changes (Fig. 1). In this case, the monitoring system works exactly according to Annex IV of the Directive 2002/59/EC of June 2002. I quote: �Where, following an incident... that authority may, inter alia: a) restrict the movement of the ship or direct it to follow a specific course�.

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6. Port of Gdańsk � examples of Harbour Master�s assistance: �� Ships in the harbour are always informed in advance about storm warnings, �� When the harbour is closed due to heavy, dense fog, the ferry on arrival is

ordered to drop anchor, �� Fire on board a ship next to the ferry berth � decision to leave the harbour

immediately.

Fig. 1. Track of cargo vessel heading directly towards rocks before and after course alterations done according to advice given by VTS and MRCC Goteborg�s operators.

4. Conclusions To sum up, the above examples of practical support with the use of the existing VTMIS system and its components show that that ship operation on the Baltic Sea is becoming more and more safe. To my knowledge, based on consultations with captains of ferries operating on the route between Świnoujście and Sweden and maritime bulletins, there are plans to put the traffic off the Polish coast and along it in the E � W direction in order. For years ships due to navigational difficulties generally avoided the area of �Słupska Bank�. Then, year by year more and more ships, among these even deep draft vessels, started using the route south of Bornholm. Nowadays, both the users and the Administration are convinced that establishing a TSS in the area is necessary. Another idea, which seems to be very useful, is to install an additional AIS station on MOU Petrobaltic (known among seamen as �The Polish Kuwait�).

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Some advantages of the above mentioned station is its offshore placing, the height of its antenna and the planned transmitter power of 25W. This will significantly extend the coverage of the AIS system and allow for monitoring traffic up to about 80 Nm norths off the Polish coast (see Table 1 and Fig. 2). As to other particular parts of the Baltic Sea I have not sufficient knowledge about the needs to establish new TSSs. The question of efficiency of radio communication in emergency and distress signals is still open. The incident involving two Estonians drifting for two days on a motor yacht with a broken engine and waiting for rescue proves that there is something more to do. It is insufficient to depend on mobile phones only. Introducing AIS class B and AIS SART may improve the situation and partly solve this problem.

Table 1. Usable coverage range of the AIS station installed on MOU Petrobalitic (information received from Maritime Office in Gdynia).

Transmitter power [W] Ship�s antenna height [m] Usable range [Nm] 4 32.0

10 10 34.8

4 36.8 25

10 39.7

Fig. 2. Range of coverage of the AIS station installed on the MOU Petrobaltic for transmitter power 25 W and ship�s antenna height 10 m; green line � boundary of the Polish Exclusive Economical Zone (EEZ), red � boundary of the Polish SAR region (information received from Maritime Office in Gdynia).

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The New German Strategy to Deal with Maritime Emergencies at Sea and on the Coast

Michael Akkermann Central Command for Maritime Emergencies, Germany

MAkkermann@havariekommando.de

More than two decades before the Central Command for Maritime Emergencies (CCME) had taken up operation in January 2003 major maritime emergencies were to be managed by three different decision taking bodies. These bodies were based on three different administrative agreements between the Federal Government and the Federal Coastal States organising joint response to accidental marine pollution, to major shipping disasters and to fire fighting at sea, as required by the different powers and responsibilities designated to the Federal Government and the Federal Coastal States Governments by the German constitution. A National Reporting Centre (ZMK), two marine pollution response units and three different decision committees were responsible for counteracting all aspects of major maritime emergencies. The PALLAS Incident (1998) has initiated the revision of the German Maritime Emergency Response Organisation. Because of its federal constitution German law provides for allocating responsibilities to the Federal Government and the five Federal Coastal States Governments in the field of Maritime Emergency Response. Safety of shipping at German shipping lanes and in territorial waters is under supervision of the Federal Ministry of Transport, Building and Urban Affairs while civil protection matters, water quality and waste management control responsibilities are within the remits of Federal Coastal State Ministries and Agencies.

North Sea Baltic Sea

Fig. 1. Geographical Area of Responsibility.

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The CCME is a joint institution of the German Federal Government and the Federal Coastal States. It was established to set up and carry out mutual maritime emergency management in the North Sea and in the Baltic Sea. It is based in Cuxhaven (Northwest Germany). The Central Command for Maritime Emergencies is headed by a federal official. During daily work routine the CCME consists of about 40 employees, working in five different sections. The five sections are: �� Maritime Emergencies Reporting and Assessment Centre (MERAC) �� Marine Pollution Control / High Sea and Salvage Section �� Marine Pollution Control / Coastal Section �� Fire Fighting, Rescue and Medical Response Section �� Public Relations Section

During daily work routine the five sections form a "centre of competence", which deals with all questions related to maritime emergencies. In case of a Complex Emergency Situation, the staff is alerted and called for to co-ordinate immediate action of all necessary forces under the auspices of the Federal Government and the Coastal States. Personnel from the CCME form this "Central Casualty Command", which is organised in four units. The head of the CCME takes the captaincy of the staff. The section heads are supposed to take over most prominent tasks of the staff units.

Fig. 2. Organisation of CCME

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These arrangements under a centralised command structure allow rapid and comprehensive control of all necessary operations in major maritime emergencies. The CCME hereby utilises personal, equipment and know-how of all authorities and institutions of the federal government, the coastal states and private organisations responsible for the sea and the coastal area.

Fig. 3. Location of German Oil Spill Vessels and Gear

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Handling Risks to Maritime Oil Transportation in the Baltic Sea � a Danish Perspective

Per Sønderstrup Danish Maritime Authority, Denmark

ps@dma.dk

Abstract Maritime transportation of oil and oil products has showed a sustained increase within the Baltic Sea for the last decade. This has mainly been driven by oil exports from Russia, which has become a major oil exporting country especially for the European market. Furthermore, economic growth in the Baltic Sea region drives the need for maritime transportation in general, both regionally and for import and export purposes. Although the present financial crisis might change short-term factors also affecting the demand for maritime transportation, there is little doubt that in the long run economic growth will be an underlying factor that will increase maritime traffic within the Baltic Sea. Taking into account that oil exports from Russian oil terminals is estimated to increase by as much as 100 million tons per year, coastal States will have to manage the risks of increased maritime traffic in terms of accidental oil spills from ships� collisions and groundings, but also the fact that intended oil discharge from ships is still a prevailing polluting factor.

This paper presents developments in maritime traffic and ship accidents to show some of the challenges a coastal State faces to prevent oil spills and discusses how to handle the risks. As a coastal State, Denmark has two gateways to the Baltic Sea that are difficult to navigate and are characterized by dense traffic. These gateways are at the same time international straits that require international regulations. The Danish strategy is to minimize the risks by enforcing proper preventive measures in terms of safety of navigation, proper aids to navigation, genuine international regulations for the operation and construction of ships and competent crews assisted by Vessel Traffic Systems and pilots. Additional Danish strategies involve effective monitoring systems for ship traffic, detection of oil spills and identification of ships that violate the regulations.

Several efforts have already been made to minimize the risks of marine accidents many of those triggered by major ship accidents. These efforts have so far proved effective. Denmark has not experienced any major oil spillage since 2001 and the number of accidents is, if not decreasing, then maintained at a low level.

One key challenge is how to be one step ahead, i.e. how to prevent risks from increasing and how to react before a major accident calls for new preventive initiatives. There is no simple answer to this, but we are in a far better position today to estimate and handle the risks by risk models and systems like AIS, better knowledge of ships� movements by integrated information and monitoring systems and better communication tools.

1. The Danish gateways to the Baltic Sea The Danish Maritime Authority (DMA) is part of the Ministry of Economic and Business Affairs and it is the principal authority as to the coastal State responsibilities of Denmark. Some operational issues, such as handling ships� passage through the Baltic straits and Danish territorial waters, preventing or cleaning pollution, etc., are the responsibility of the Admiral Danish Fleet under the Ministry of Defence and the Ministry of the Environment, which handles legal issues and enforcement of legislation on protection of the marine environment.

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As a gateway to the Baltic Sea, Denmark has two main routes for ships navigating in and out of the Baltic Sea � one is the Sound and the other, the major route, is the Great Belt, which is also primarily used for larger tankers. The general pattern is that tankers in ballast come through the Sound in order to enter into the Baltic Sea, and when loaded they pass through the Great Belt on their way out of the Baltic Sea. The major part of tankers passing through the Great Belt is loaded tankers, although some of the passages are made by tankers in ballast. The entrances to the Baltic Sea are international straits that follow the principle of right to innocent passage. Furthermore, the Copenhagen Treaty from 1857 applies, which stipulates that using a pilot when passing through the Straits should be voluntary. A mandatory pilot scheme for the Great Belt and the Sound thus cannot be introduced without international acceptance. The Great Belt is an ancient riverbed providing just a narrow fairway for the ships to follow. However, this cannot be seen from the surface and, consequently, requires thorough route planning and a high awareness during the voyage. The Great Belt is characterized by strong sea currents that sometimes have different directions at different depths. For example, the direction of the surface current might be opposite to that of the currents at a depth of 6-8 meters. The best way to illustrate the difficulties navigating the Great Belt is to see the Belt from satellite (see below).

One of the �hot spots� is Hatter Barn, which requires timely maneuvres of up to 90 degrees with deep draught vessels. The difficulty of the Hatters Barn is immediately recognized when you see the riverbed, but the OOW (Officer of the Watch) must fully understand and prepare for this when looking at the charts. The Hatter Barn has experienced groundings for several years. One of the common causes for this can be illustrated by the grounding of the FOTINI LADY. The ship did not react timely to alter its course to starboard. Fewer groundings seem to take place now that new navigation marks have been introduced as well as thorough VTS monitoring of the area. However, proper knowledge of how to navigate the Great Belt is of major importance. The use of a pilot especially on deep draught vessels therefore is an important risk-reducing measure that Denmark has promoted internationally for several years.

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2 Development in ships� traffic The risk of collisions and groundings can be measured in terms of the number of ship passages and traffic, but also in terms of the size of the ships passing. Larger ships carry larger amounts of bunker oil and, in addition, tankers also carry oil and chemicals as cargo. The period 2001-2007 has witnessed significant changes in the traffic volume. For the Great Belt the increase was 10%, which is in fact not a very high growth rate, but when it comes to the size of the ships the increase in the average ship size was 63%. For tankers there was a major increase as the number of tankers increased by 33% and the average size almost doubled with an increase of 97%. In the Sound the statistics differ. In fact the number of ship passages has slightly decreased (6%) or is constant, but again the increase in average ship size is 18%. The same pattern applies to tankers with only small fluctuations in number but the average tanker size has increased by 76%. Especially for the Sound the draught limitations restrict the size of ships passing as the maximum depth of Drogden just south of Copenhagen is 8 meters. The Danish Ministry of Defence prepared a report in 2007 to evaluate the oil spill response capacity and to protect the marine environment. According to this report, future tanker traffic through the Great Belt will increase by 28% in 2015 and by 35% in 2020. If analysed further, the main increase will be seen in large tankers. In particular the amount of oil transported increased during the period. In 2001, 81 million tons were transported and by 2007 this figure had increased to 170 million tons. The prospective is that this figure will likely increase by 100 million tons in the future. If the size of tankers does not change, the increase in tanker traffic will be 1000 tankers per year or 2-3 tankers per day. This will not lead to congestion in the Great Belt and the number of tankers might even be less because it is expected that tankers will be optimized to carry more oil by increasing their length and breadth to overcome the draught restriction due to limited depth. However, larger tankers passing the narrow fairway, with more oil, should cause concern and call for further awareness.

3. Ship accidents � new trends and developments A few years ago the Danish Maritime Authority made a statistic study of the reasons for groundings in order to see what could be done in terms of safety of navigation and to identify major risk factors. In the Great Belt, which is one of the most difficult areas to navigate, there were 46 groundings in 8.5 years (between 1 January 1997 and 1 July 2005), especially in the Hatter Barn area, and the pattern revealed that the ships grounded did not have a pilot. In 2004 the estimation was that the cost of a grounding at Hatter Barn was about USD 3 million (in case no ecological damage occurred) and this should be compared to the cost of a pilot of just USD 7,500. Today it is our experience that approximately 98% of the passing ships take a pilot according to the internationally adopted recommendation for the usage of pilot in Route T and the Sound. In 2007 the Danish Maritime Authority published a report on marine accidents, including accidents in Danish waters. The geographical distribution of the accidents registered in the period 1998-2007 shows several �hot spots� in the main navigation routes. The hot spots are concentrated at Hatter Barn as previously mentioned and Agersoe Flak, which requires timely manoeuvres similar to the Hatter Barn. In the Sound a �hot spot� is positioned at the fairway Drogden just south of Copenhagen. Drogden is characterized by its narrowness and limited depth.

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Although more detailed analyses are necessary to thoroughly explain the root causes, a general pattern is that accidents happen due to navigation errors on ships that do not take a pilot. It is seldom that we see malfunctioning of ships� equipment. In the period 2001-2007, the number of ship accidents in the Great Belt and the Sound fluctuates and it is difficult to assess the development in accidents based on these figures. This is due to the fact that fortunately the number of accidents is rather limited. Many of the accidents cause no damage to the hull of the ships or require only minor repairs. In the same period, the size of the ships and the traffic density have increased significantly and, if we compare the number of ship accidents with the number of ship passages, there is a clear tendency towards fewer accidents measured in number of accidents per 10,000 ship passages. An important observation is that although ships size and the number of passages are increasing the frequency in ship accidents is declining and therefore there is no clear correlation between accidents and increase in traffic. In these terms, safety of navigation has improved over the period. One type of accident that has drawn public concern is groundings off the coast of Bornholm. On 24 February 2008, the WANI WILL grounded because the ship failed to alter its course to follow the route north of Bornholm. The Danish Division for Investigation of Maritime Accidents concluded that the reason was that the 2nd officer was incapacitated due to alcohol consumption and had left the bridge unmanned. At the same time, the master did not ensure that the 2nd officer was fit for duty. An almost similar accident happened when the MCL TRADER grounded on 17 May 2008 just south of the port of Roenne (on Bornholm) because it failed to alter its course to port to follow the route north of Bornholm. Although the Danish authorities tried to get in contact with the ship, it did not succeed in avoiding the grounding. The conclusion of the Danish Maritime Authority�s Division for Investigation of Maritime Accidents was that the causes were insufficient watch-keeping, fatigue and that the master was under the influence of alcohol. Again in March 2009 we experienced a grounding in Drogden due to the intake of alcohol. This time the ship KARIN SCHEPERS grounded after taking a dangerous path down south thorough the Sound. Although the Danish Admiral used every means to get in contact with the ship, the ship continued and ended up grounding. Both the Master and the chief mate were imprisoned by the police due to the intake of alcohol. Since the Danish Maritime Authority has experienced accidents, groundings or near-misses several times caused by either one of the above or a combination of the above three reasons, it has proposed the introduction of an international mandatory requirement for a mandatory bridge navigational watch alarm system which is to be adopted at MSC 86 later this year, as agreed at MSC 85 December 2008. Furthermore, Denmark is actively supporting the proposal for international mandatory limits for alcohol consumption into the STCW Convention. Unfortunately, as the above examples clearly illustrates, this issue cannot be left to be regulated by the industry itself, and clear rules are needed. Although the problem is not normally seen on tankers because they have a high quality standard including non-alcohol policies, they interact with normal traffic and therefore the risk of a collision will increase if other ships do not enforce the same strict policies.

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4. Oil spills and risk assessments The Admiral Danish Fleet has the responsibility for monitoring oil spills in Danish waters. The surveillance is carried out by different means ranging from satellite pictures (in 2008 397 pictures were received from Kongsberg Satellite Services and from EMSA (European Maritime Safety Agency)) and 500 flight hours with military airplanes to reports from pleasure craft � more than 8400 pleasure craft have volunteered to participate in this reporting scheme. The annual report for 2008 concluded that the number of registered oil spills is almost constant, but there have not been registered any serious pollution accidents in 2008 in spite of the traffic increase. In 2008, 3.3 million tons of oil were transferred in ship-to-ship operations (STS) in Danish waters. Due to the draught restrictions in some Danish waters, STS operations are carried out primarily at the two Danish ports of Frederikshavn and Kalundborg where very large crude carriers (VLCCs) are fully loaded to their marks. Denmark has implemented a regulatory regime for STS operations in Danish waters that includes a formal approval scheme for STS operators. The scheme has proven effective as accidental oil spills from STS operations are very seldom. When dealing with oil spills, two risk scenarios should be taken into account � namely intended or accidental oil spills and oil spills from ship accidents. In Danish waters, the prevailing cause for oil spills is �intended oil spills�, of which 419 reports were received and 108 oil spills were identified in 2008. This should be compared to oil spills from ship accidents, where only one oil spill occurred. This could lead to the conclusion that the main risk emanates from intended oil spills from ships that, for whatever reason, discharge residues into the sea. However, if we take into account the damage to the marine environment in terms of the amount of oil spilled, ship accidents still represent a major risk factor. Based on known data on oil spills from ship accidents, the amount of oil spilled in a risk model made by COWI was 1900 tons compared to 350 tons from intended oil spills. Consequently, the frequency of oil spills must be held up against the impact on the environment. In October 2007, the Danish Ministry of Defence published a risk analysis of oil and chemical pollution in Danish waters. The report mapped the present risk of oil pollution and the future projection of the risks. The conclusion is that the main risks of marine pollution from oil and chemicals are closely related to the main Route T through the Great Belt and are also closely related to the �hot spots� identified as particularly difficult to navigate. When it comes to how to reduce the risk of oil and chemical pollution, the strong correlation indicates that preventive initiatives should focus on means of improving safety of navigation. This might not be a surprise, but what really draws attention is the estimate that the future risk in the �hot spots� is likely to increase. Therefore, there is a need to closely monitor developments in ship traffic and ship accidents and to foresee these development in order to implement appropriate preventive measures.

5. Conclusions Several efforts to reduce the risk of marine pollution have been made both at the national, EU and international level. So far, these initiatives have proven effective, as the number of accidents has decreased in a period with increasing traffic. The international recommendation to use a pilot when navigating through the Great Belt and the Sound is now followed by 96-98% of the ships. Still a few ships draw

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attention and concern. The challenge for the coastal state is to identify these ships by all means so proper preventive actions can be taken. This relative small share of ships represents an unknown risk factor. Here the use of pilot has proven effective and from a Danish point of view our objective is to achieve 100 %. Higher structural standards have been implemented and better means for navigation are now available (for example the use of electronic chart display and information systems (ECDIS)). At the same time, improved surveillance in the form of AIS and Vessel Traffic Systems has proven to be supportive for the safe handling of ship traffic. Strict enforcement of maritime regulations through flag State and port State control is an important contributing factor. Due to the expected increase in traffic, it is necessary to assess the preventive measures already introduced. The risk models presented suggest a future increase in the risk of oil spills. This risk must be minimized and a main contributory factor is to maintain quality shipping at all levels. Competent crews on ships of a high technical standard are of major importance to the prevention of accidents and oil spills. If such ships are assisted by coastal States that provide effective aids to navigation, competent pilot services and Vessel Traffic Systems, it is the opinion of the Danish Maritime Authority that the risks can be handled at a satisfactory level.

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The Need for Coordinating Shipping and Traffic Control in the Baltic Sea Area � Gdańsk 24 April 2009

Johan Franson Swedish Maritime Administration, Sweden

johan.franson@sjofartsverket.se

I am very pleased to be able to address the participants in this symposium. The symposium is a good example of � in a way � co-operation among the Baltic littoral states when it comes to shipping and maritime safety matters. When I looked at the programme I noticed that our present session has two presentations with titles which are almost the same. Let me say that I am glad I am the first of the two speakers, which means that I will not � in the worst case � be standing here and repeating what somebody else has already said. Let me secondly say that the title of my presentation should really be �The Need for co-Ordinating Shipping and Traffic Control in the Baltic Sea Area?�. There should be a question mark after the title. The reason for the question mark is that we sometimes hear from different quarters the call for surveillance and control of maritime traffic in the Baltic Sea Area. By surveillance and control I mean that somebody in a centre is keeping check on the ships and their movements and possibly giving them advice. The background to these calls for surveillance is, in a sense, political and sometimes refers to the positive experience from the Gulf of Finland Mandatory Reporting System � GOFREP. In Sweden there have been people who have said that the dense maritime traffic in the Baltic merits a surveillance of the traffic, at least in the Baltic Sea proper. Even representatives from the Swedish Shipowners� Association have publicly called for this. The calls for surveillance have in Sweden often been coupled with the proposal to put a surveillance centre on the island of Gotland. If this has anything to do with regional policy in Sweden remains unclear but I harbour a suspicion that it does. Now, let us look at the maritime traffic in the Baltic Sea Area. What is it like? What do some people want to arrange surveillance of? I have not recently had an analysis of the available Automatic identification System (AIS) data made but when we made our submission to the IMO some years ago for Additional Protective Measures in connection with the designation of the Baltic Sea Area as a Particularly Sensitive Sea Area (PSSA) we said that in this area there were some 2 000 ships sailing every day, excluding ferries and fishing vessels. There is no reason to believe that there are fewer today, albeit the present economic recession may have dampened things a bit. Looking back in time and looking forward in time I do not think there is any doubt, however, that in the long term perspective we will have a substantial increase in maritime traffic, making the Baltic Sea Area, and especially the Baltic Sea proper, an area with a dense maritime traffic. We have an economic recession today, as I have said, but that will hopefully pass and economic growth will resume and with that trade and maritime traffic will come back.

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What is most remarkable with the development of maritime traffic in the Baltic Sea Area is not really the growth of the number of ships trading but rather the growth of ships� sizes. This is mainly due to the growth of shipments of oil from the Russian Federation, requiring large tankers. One rather curious detail is that when we submitted our proposal for Additional Protective Measures in the Baltic Sea in conjunction with the designation of the Area as a PSSA, one of these measures was to limit the allowed draught of vessels passing through the Traffic Separation Scheme (TSS) Off Gotland, i.e. the TSS just south of the island of Gotland, to 12 metres. There was a rock at a depth of 16 metres, which was too close for safety to the southbound lane. This rock had up to that time not been a problem because maximum Baltic draught, i.e. 15 metres, was in the old days the case only for ships inbound. With the exportation of Russian oil we suddenly had a rather large number of deep-draught tankers sailing outbound. This leads to the limitation of permissible draught and the creation of the DW-route. The large oil tankers are a new feature in the traffic pattern in the Baltic Sea proper. Some of the ships are truly large and only partly laden when leaving the Baltic; their tanks are topped up when they have sailed through the Great Belt. So we have, over time, an increase in traffic density, in all probability an increase of all categories of cargoes, including dangerous bulk cargoes and IMDG goods, and very definitely an increase of the amount of oil transported. Considering the fact that the Baltic Sea Area is an ecologically very sensitive sea area � remember the PSSA designation � is there then not reason to try to co-ordinate and control the movements of ships in the Baltic? My answer to that question is No! It is �no� as far as the overall coordination and control, meaning there is a centre coordinating and controlling, of ships� traffic in the Baltic Sea Area are concerned. Why is this the answer? There are several reasons. And the reasons are interlinked with each other. But before we go into the reasons more in detail, let us have a look at the Baltic Sea Area. It consists of the Baltic Sea proper, the Gulf of Finland, the Bothnian Sea and Gulf and the Kattegat and Skagerrak south of the latitude parallel through the Skaw. In the area there are also, naturally, the entrances to the Baltic Sea through the Belts and the Sound between Denmark and Sweden. In this connection I think we can disregard the Sea and Gulf of Bothnia. The traffic is not dense there; it is rather sparse, as a matter of fact. There is no reason to coordinate or control the traffic in those areas. The traffic in the Gulf of Finland is dense with big tankers, cargo ships and ferries, some of which are crossing the main shipping routes. The traffic through the part of Skagerrak, which belongs to the Baltic Sea Area, and the Kattegat is certainly dense because the majority of ships entering or leaving the Baltic pass through those waters; a minority of ships uses the Kiel canal. The Baltic Sea proper has a dense maritime traffic. I am certainly not an expert on GOFREP but we all know that it is ship reporting systems (SRSs) which are run by Estonia, Finland and the Russian Federation. The reporting systems are there for the very simple reason that accidents in the area, especially if they involve large tankers, may directly affect the three countries.

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Other Baltic countries may also be affected as well by an accident depending on prevailing winds and waves. There are good reasons for all littoral states of the Baltic Sea to support GOFREP. Maritime traffic through the part of Skagerrak, which is part of the Baltic Sea Area, and Kattegat is mainly something for Denmark and Sweden. I have said that the maritime traffic is dense but everything is relative � it is open sea. We have, historically, had the odd grounding and collision but I do not think anybody would call the accident rate alarming. As far as the two international straits, the Great Belt and the Sound, being the main entrances and exits to and from the Baltic Sea, are concerned, these are problematic areas from a maritime safety point of view. The navigable waters are narrow and traffic congested and sometimes very dense. There are SRSs working in both areas and vessel traffic service VTSs to handle the ships� reports. The Sound SRS, which is still voluntary, covers only part of the Sound but this will hopefully change in the future. The problem for Denmark and Sweden with the Great Belt and the Sound is that they are international straits and, furthermore, international straits with a historical regime, i.e. the treaty from the 1850s dealing with the rights of shipping through them. This limits what the two states can do as far as safety of shipping is concerned. Amongst other things, the treaty prohibits compulsory pilotage in the two straits. The Baltic Sea proper has � as I have said � dense traffic. There are two main areas which should be noted; firstly, the areas adjacent to Bornholmsgat and Bornholmsgat itself, and secondly the areas off the southern parts of the islands of Öland and Gotland. The stream of ships is compressed in these areas. There are other areas, which cause concern as well, like the area south of the island of Bornholm and north of the coasts of Poland and Germany. In connection with the designation of the Baltic Sea Area IMO decided a number of APMs. One of these was the TSS in the Bornholmsgat and another the DW-route leading from the Bornholmsgat to the Gulf of Finland. If one compares the traffic pattern before the establishment of the TSS to the pattern after the establishment, the difference is like day and night. The traffic flow today is ordered and a look at the ships using the TSS off Gotland shows that very few ships with a draught exceeding 12 metres use it but sail in the DW-route instead as they should do. In my opinion the TSS in the Bornholmsgat is the most important improvement of maritime safety in the Baltic Sea area for a long time. More routeing measures are on the way. Sweden and Finland have proposed a system of TSSs and a DW-route in Ålands hav, which will be accepted by IMO. Sweden will furthermore submit proposals for four new ones to IMO�s sub-Committee on Safety of Navigation, which meets this summer. Poland and Germany are submitting proposals for routeing measures south of the island of Bornholm. Denmark and Sweden have begun to look at the routes in the Kattegat but that work has not yet advanced to the stage where a submission to IMO is imminent. There may be other measures, which I do not know about. Apart from these routeing measures a few words should also be said about the improvements in the ships themselves and I will limit myself to the improvements concerning safety of navigation. Recent years have brought improvements in radars and we have a carriage requirement concerning the Electronic Chart Display and Information System (ECDIS). We also have a carriage requirement concerning AIS.

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Recent years� development has improved the possibility of the navigating officer of a ship to decide the ship�s position vis-à-vis land and areas with a shallow depth. The possibility to position a ship vis-à-vis other ships has also been improved. We should not forget that the AIS, at the inception of the system, was meant mainly to be a piece of equipment for communication ship-to-ship, i.e. an anti collision equipment. I feel that we, who are shore based, tend to overemphasize the use of AIS to follow-up maritime traffic; it is primarily anti collision equipment. I think that the routeing measures, which have been established and which are planned, will taken together significantly raise the level of navigational safety in the Baltic Sea Area and taken with the improvement in the ships themselves, they will raise the safety of navigation to a probably acceptable level. I have previously said that the maritime traffic in the Skagerrak, Kattegat and the Baltic Sea proper is dense. But that is dense in comparison to traffic in other sea areas. It is still open sea. If we were to have � as it were � a VTS for instance for the whole of the Baltic Sea proper, what would it do? I cannot at this stage see any meaningful tasks for it. The operators could not very well begin to interfere with the navigation of individual ships. The costs of such a VTS would be enormous since it would require several operators on a 24/365 basis. A cost/benefit analysis would probably result in the costs not being in relation to the gains in safety. Apart from this we would run into a legal problem. SOLAS Convention Chapter V-12.3 says that the use of VTS may only be made mandatory in sea areas within the territorial seas of a coastal state. The greater part of the Baltic Sea is outside territorial waters as are the greater part of the routeing measures. That would mean that participation of ships in a VTS would have to be voluntary. The fact that VTSs cannot be mandatory in waters outside territorial waters has sometimes been circumvented by having a mandatory SRS according to SOLAS V-11; these can be established outside territorial waters and be handled by a VTS. In reality you then get a VTS being, in a sense, mandatory in waters outside territorial waters. But it is difficult to see the establishment of a SRS for the whole of the Baltic Sea � at least for the foreseeable future. Would the majority of ships see a benefit of such a system? I doubt it and their participation would naturally be crucial for the system to work. I think we would have a hard time in IMO to convince the international shipping community that such a system would enhance safety. We should remember that there is some resistance within IMO against creating more and more SRSs. What I am suggesting as far as maritime traffic in the Baltic Sea is concerned is that we should follow the traditional way, i.e. establish SRSs and VTSs according to the requirements of SOLAS where they are needed. Establish routeing measures where such measures would enhance safety. The accident rate is today not alarming. But � we have reason to believe that once times turn better we will have a continued increase in traffic volumes. I am fairly convinced that traditional routeing measures will handle this situation but in order to acquire more knowledge and certainty I think an FSA study or some other analysis of the risks inherent in maritime traffic in the Baltic Sea Area, given the routeing matters we have and will have, should be performed. Then we can make a more informed decision and plan whatever action we would have to propose to IMO.

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Coordinating Shipping and Traffic Control on the Baltic Sea

Hans-Heinrich Callsen-Bracker Ministry of Transport, Building and Urban Affairs, Germany

Abstract This paper considers the possibilities and prerequisites of traffic control measures in the Baltic Sea. Furthermore, it indicates the necessity of working together not only within the relevant international organisations such as IMO or HELCOM, but also in the field of sharing traffic data, survey and study results in order to be able to conduct reliable analyses to provide a sound basis for the development of safety-enhancing measures in the Baltic Sea which could be accepted by the International Maritime Organisation IMO.

Keywords IMO, Baltic Sea, HELCOM, traffic control measures,

1. Background On the occasion of the Extraordinary Ministerial Meeting of the Helsinki Commission, in Copenhagen on 10 September 2001, the Contracting Governments declared their willingness to work together on ship safety matters within the framework of HELCOM. As a result of the meeting, the Ministers signed a �Declaration on the Safety of Navigation and Emergency Capacity in the Baltic Sea Area� (HELCOM Copenhagen Declaration) and agreed upon a number of initiatives to enhance the safety of navigation and the prevention of pollution in the Baltic Sea. However, the International Maritime Organisation IMO is the only international organisation responsible for establishing routeing measures in international waters.

2. Introduction The overall aim of any proposal on shipping and traffic control is to achieve risk reduction measures, which encompass the risk of pollution and damage caused by collisions and groundings as well as the improvement of traffic efficiency. The International Maritime Organisation IMO is recognized as the only international body for developing guidelines, criteria and regulations on an international level for ships' routeing systems. According to the International Convention for the Safety of Life at Sea (SOLAS), the Contracting Governments shall refer proposals for the adoption of ships' routeing systems to IMO. The SOLAS Convention requires that where two or more Governments have a common interest in a particular sea area, they should formulate joint proposals for the delineation and use of a routeing system therein on the basis of an agreement between them. This procedure has been applied very successfully in the past several times by all Baltic States on a very open and cooperative basis. For this purpose HELCOM Expert Working Groups have also been used as a platform for discussing such questions of common interest.

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I would like to mention in this context the joint submissions by the Baltic States, which were developed by different states and then discussed jointly on several occasions. The result of such joint endeavours was, among others, the recently successfully introduced new ships` routeing systems, namely the TSS Bornholmsgat and North of Rügen.

3. Shipping and Traffic Control All measures considered have to be in compliance with the guidelines and criteria developed by IMO. This is the framework, together with the principles of the International Law of the Sea Convention, UNCLOS 1984. Therefore, co-operation among Governments having a common interest in the Baltic Sea area is required in the field of hydrographic surveying, collecting data for traffic analysis and for tailoring and finetuning measures, taking due account of the special national requirements for environmentally friendly, secure and reliable shipping over sea. For some of these points supportive platforms were established on the basis of the HELCOM Copenhagen Declaration. I would like to mention in this context some of the agreed Terms of Reference:

�� To improve existing routeing measures in the Baltic Sea Area �� To enhance the use of pilotage in Route T and the Sound �� To adopt additional measures to ensure improved hydrographic services and to

promote the use of Electronic Navigational Charts (ENC) �� To enhance the use of Automatic Identification Systems (AIS) �� To provide systematic and updated guidance and information related to safe

navigation to relevant stakeholders trading in and out of the Baltic Sea Area I am referring to the HELCOM Expert Working Groups for AIS, for Ships� Routeing, for Pilotage and Hydrographic Surveying. But these groups are established only for a certain period of time and the topics addressed by these groups are, in my view, not directly linked to HELCOM but guided by IMO instruments and the IHO. Therefore, there is a clear need to have, besides HELCOM groups, a platform for discussing and preparing proposals of ships� routeing measures in the Baltic Sea which at the end should be presented to the IMO for adoption. If measures are carefully developed and discussed by all parties involved, which is always an iterative process, there is a very high probability that the implementation of the proposed routeing measures will provide a demonstrable decrease in the traffic characteristics that are of relevance to potential conflicts and other risks such as groundings. But what are the prerequisites for effective measures and a successful application and submission to IMO? Due to the availability of real traffic data we are to date able to analyse the actual traffic situation on the basis of recorded AIS information in the area concerned. With these real traffic data we are simulating the effect of different possible routeing measures and evaluate the effect to the traffic pattern in the sea area. We applied the method of a statistical study concerning tool for traffic simulation and analysis based on real AIS traffic data for the first time in 2004. Our aim was to demonstrate and justify to the IMO the proposal for a new traffic separation scheme North of Rügen. Now, after having introduced this TSS in 2006, it can be concluded that the anticipated safety enhancing effect as assumed in the findings of the study is confirmed.

39

In the future there may be a need to address possible routing measures in crossing areas where east and westbound transit traffic lines are meeting north and southbound shipping routes such as ferry lines, and in junctions of TSS or deep-water routes. And this may also include the consideration of joint VTS Centres as well as Ship Reporting Systems to cover international waters.

4. Further measures and obligations After having collected and compiled all necessary hydrographical data, traffic and shipping service information, this information should be kept up to date and disseminated within the shipping industry. To assist this process, the HELCOM EWG on transit routing developed the Mariners� Routeing Guide Baltic Sea. This nautical information should be available and directly accessible on board of every ship sailing in the Baltic Sea. This nautical chart provides essential information for safe navigation in the region. The Guide supplements the nautical chart portfolio for the Baltic Sea. It includes information on reporting systems, ice conditions, maritime assistance services, special regulations, as well as water levels and land rise. Furthermore, there are not only obligations for SOLAS Contracting Governments, but also for shipping companies. Because the companies have to ensure that the Safety Management System is maintained to provide for safe practices in ship operation and should establish safeguards against all identified risks; that means that relevant procedures are introduced under the ISM Code. The required procedures must include guidelines for the determination of underkeel clearance, for using pilot service according to international recommendations and for following recommended transit routes in the Baltic Sea. I would like to stress the fact that this is a clear requirement of the ISM Code. We should especially look at these points during the ISM audit process and also during the office audits before.

5. Technical background for the proposal of a TSS Adler Grund The initiative to discuss new traffic measures in the sea area was launched some years ago by Poland and I would like to use this opportunity to express my appreciation to Mr. Bogdan Rojek from the Maritime Office in Gdynia. He was the driving force and prepared the main part of our joint sub-mission. The goal of the simulation project conceived by the Federal Ministry of Transport Building and Urban Affairs was the investigation of traffic regulation measurements covering the sea area South of Bornholm. The investigation is based on the comprehensive AIS � data pool covering a time frame of about 5 months. The influences of possible traffic regulations were simulated and statistically evaluated as regards the collision conflict potential of approaching vessels. The current vessel traffic situation was compared and evaluated with the three developed possible traffic regulation measurements. The estimated results were presented to the ad hoc work of the Expert Working Group of the HELCOM �Transit Routeing�.

40

The results of the study conducted by the HSW Warnemünde1 are described briefly as follows:

�� A representative traffic profile of the traffic situation South of Bornholm resulted from the investigation. The shoals Adlergrund / Roennebank and Slupska Bank cause diverting and crossing courses and the risk of groundings in this area (see Figure 1). The mean traffic density amounts to about 30 vessels per day.

�� The flow of transit vessel traffic is mixed and its directions overlap. The number of west-going vessels is approximately equal to the number of east-going vessels.

�� The developed routing measures should separate the vessel traffic with respect to the travel direction and reduce the navigational space. The goal is to harmonize the traffic flow and enhance navigational safety.

�� The operating results found during the project were used for the scientific and technical associated work of the national experts as well as by the expert working group �Transit routeing�.

By finetuning a final proposal, also on the basis of the scientific findings provided by this study Germany, Denmark and Poland submit a common proposal on new TSS (see Figure 2) for enhancing the traffic situation South of Bornholm for consideration at the forthcoming session of the IMO Sub-Committee on Safety of Navigation.

6. Conclusions As a result of the basic study mentioned above, the following is quite evident: The implementation of the proposed routeing measures will provide a demonstrable decrease in the traffic characteristics that are of relevance to potential conflicts and the risk of groundings. The current conflict potential as well as the risk of groundings may be enormously reduced by the separation and organisation of traffic through the implementation of a traffic separation scheme with separate traffic lanes according to the direction of traffic flow. Such conflict potential reduction is particularly evident as regards encountering situations. The statistical data outlined in the study go to prove this point.

1 Leader of the Project: Prof. Dr.-Ing. Reinhard Müller; Dipl.-Math. Michaela Demuth, Dipl.-Ing. Frank Hartmann;

In co-operation with Maritime Office Gdynia and Lotsenbruederschaft Wismar, Rostock, Stralsund and BSH Rostock

41

Figure 1

Figure 1

Figure 2

42

43

A Technically Safe Ship: View from the Lithuanian Perspective

Povilas Juozapavičius, Mindaugas Česnauskis Lithuanian Maritime Safety Administration, Lithuania

e-mail: INSPECTORATE@MSA.LT; INFO@MSA.LT

Abstract Paper describes actions, taken by Lithuania during 1990-2008, which were directed to improve the overall technical safety level of seagoing ships registered in national seagoing ships� register. The paper examines the problem of technical safety of ship in the context of relevant administrative measures, without analysis of technical aspects of the matter. This approach allowed us to review the history of development of maritime safety policy in Lithuania, beginning from the date when Lithuania restored it�s independence in 1990 till nowadays.

Keywords: ships� technical safety, accident rate, port state control, maritime conventions

1. Introduction One of the primary goals of flag state administration is to ensure safety of ships flagged by its state flag and that these ships do not pose a threat to the marine environment. Usually this goal is achieved by implementing international requirements and by taking relevant administrative actions. The aim to ensure maritime safety and prevent pollution from ships can be achieved by implementing two sets of measures: one of them includes measures which ensure that the ship is properly designed and built (that the ship is technically safe), and the other set includes measures which ensure that ship is properly maintained and operated (ship maintained and operated by properly trained crew) Fig. 1.

Fig. 1. Fundamental factors influencing maritime safety

In other words, a technically safe ship is a fundamental condition which is necessary in order to achieve one of the primary aims of maritime administration � ensure maritime safety. Therefore, all imposed measures which are intended to ensure the technical safety of ships, are appropriate for the overall improvement of maritime safety and prevention of pollution from ships as well.

Safe and environment-

friendly shipping

Properly designed and built ship

(technically safe ship)

Properly maintained and operated ship

(ship manned by competent and qualified crew)

44

The achievement of the objective to have only technically safe ships in a state�s ships� register, in the Lithuanian case, as well as in the case of other post-soviet bloc states, is an interesting issue. After Lithuania became an independent state in 1990, it had to be re-oriented immediately - to start execution of functions of maritime administration all alone, to form and implement a policy, ensuring that internationally agreed technical standards are dully implemented in ships flying the Lithuanian flag. It can be stated that this was a great challenge � after becoming independent, Lithuania had no national requirements and it was not a party to any nternational agreements, while the Lithuanian flag was already run up.

2. Changes of ships� technical safety level in Lithuania during 1991-2009 There is no single criterium allowing us to state that ships registered in a certain register of ships may be regarded as �Technically Safe Ships� or �Seaworthy�. However, there are certain criteria allowing us to perform a preliminary assessment of a flag state performance, in particular:

�� rating (performance) of flag state according to statistics of certain regional MoU on Port State Control (e.g. Paris MoU, Tokyo MoU, USCG);

�� accident rate; �� number/percentage of lost ships; �� number of accidents; �� number of accidents resulting in death or serious injuries to persons. Therefore, all actions by shipowners, operators, maritime authorities and other key players (recognized organizations, insurers etc.), resulting in reducing these parameters (PSC detentions, accident rate, loss of ship and deaths/serious injuries of persons onboard ship) should be considered as actions intended to decrease/minimize the risk of ships flying a certain flag with respect to potential danger to maritime safery and marine enviroment and therefore increasing general safety of individual ships as well. The number of ships registered at the Lithuanian Registry of Seagoing Ships. From 1995 to 2009 the total number of ships showed a falling trend (Fig. 2).

247

293 291 280 274 279 272

220 209 201 198175 169 159 149

0

50

100

150

200

250

300

1995 1997 1999 2001 2003 2005 2007 2009

Fishing vessels

Total number of registered ships

Fig.2. Number of seagoing ships, registered in Lithuanian seagoing ships� register

in 1995-2009

45

Until the year 2000 performance of Lithuania as a Flag State may be considered as poor and Lithuania was on the �black� list according to statistics of the Paris Memorandum of Understanding. Detention rate (percentage) of Lithuanian flagged vessels following Port State control was similar to average detention rate in this PSC region (Fig. 3), [2], [3].

16

1210 10

8

2

6

2

9

53

2,6

2,94 3,45

6,4

6,25

7,418,3

9,8

7,037,77

0

2

4

6

8

10

12

14

16

18

1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008

Det

entio

n ra

te, %

; Num

ber o

f det

entio

ns o

f LTU

fla

gged

shi

ps

Number of detentions of LTU flagged ships (Paris MoU)

Lithuanian flag detention rate, % (Paris MoU)

Paris MoU average detention rate, %

Fig. 3. Statistics of detentions of Lithuanian flagged ships

in Paris MoU region for 1998-2008

Detainable deficiencies of Lithuanian flagged ships for 1997 � 2003 are displayed below (Fig.4)

21%

19%

10%10%10%10%

40%

16%

Fire fighting

Lifesaving appliances

Charts, nautical publications

MARPOL

Crew

Emergency preparedness

ISM code

Other

Fig. 4 Detainable deficiencies of Lithuanian flagged ships for 1997 - 2003

Although in January 2003 Lithuania adopted a complementary action plan in order to further reduce the detention rate of Lithuanian flagged ships, satisfactory results indicating improvement in general quality of Lithuanian fleet were clearly visible only in year 2004 when the detention rate (percentage) of Lithuanian flagged vessels fell strongly below the average detention rate in Paris MOU region.

46

Analysis of the accident rate of Lithuanian flagged ships indicated that one of the reasons causing accidents was lack of relevant legislative measures that resulted in poor technical maintenance of ships; ship-owners were reluctant to invest in order to ensure ships� seaworthiness since there were no sanctions for non-compliance with applicable technical standards. Ships frequently sailed beyond limits of sea area in which they could operate, in 1994-1995 2 ships broke in two and sank in the North Sea. The main reason for these accidents was breach of limits of sea area in which they could operate. After relevant changes in the national legal system and enforcement of more rigorous flag state control procedures a lowering trend in the number of very serious casualties and serious casualties may be observed. Loss of one ship in 2000 should not be associated with the technical state of a ship but was caused by severe weather conditions (the ship got into epicentre of tropical typhoon and sank with its crew onboard) [1]. There was no single ship loss from the year 2002, although in previous years (1994-2002) 5 ships were lost (Fig. 5.). Moreover, as of 1995 there was no single ship loss caused by poor technical state of a ship. From 2002 to 2009 the death of 9 persons was related to cargo handling operations and there was only one case recorded when two seafarers were killed in an accident while performing abandon ship drills.

1

18

23

21 2 1

2

119

2

54

02

64

6

02

01

12 3

9

02468

101214161820

lost shipslives lostNumber of accidentsLinear (Number of accidents)

losses due to unsatisfactory technical condition of the ship

Fig.5. Number of serious and very serious accidents of Lithuanian

flagged ships during 1991-2008

3. Actions during 1991-2008 which were devoted to achieve a higher level of ships� technical safety

It was difficult to ensure technical safety of ships flying the state flag of Lithuania without a national maritime safety institution and lacking legal acts on maritime safety. Right after Lithuania gained its independence all necessary steps were undertaken to enhance technical safety of seagoing ships registered in Lithuania. In 1991, after one year since the independence was gained, Lithuania acceded to a number of main international maritime conventions - SOLAS, MARPOL, STCW, LL, Tonnage, Colreg, etc. After Lithuania became an independent subject of international maritime law the lack of human resources to carry out prescribed commitments and to put in practice requirements of the international conventions was perceived.

47

It became obvious that a special national institution for implementation of international requirements and enhancement of ships� technical safety was necessary. The high rate of serious and very serious ship accidents, treatment of Lithuanian ships as high-risk by various port State control regions were indicators showing poor technical condition of ships flying the Lithuanian flag. In 2000, the Parliament of the Republic of Lithuania adopted the Law on Maritime Safety that, inter alia, provided measures to improve the technical condition of Lithuanian ships. Another prerequite in the drive to seek the goal was preparation to become a European Union member and to gain membership of Paris MoU. Lithuania had not only to make ships flying its flag to comply with EU legal requirements but also to make every effort to reduce the detention rate of Lithuanian flagged ships in Paris MoU region. Implementation of the latter measure gave a great effect in enhancing ships� technical safety: national maritime safety policy forced shipowners either to ensure their ships met the applicable requirements or to withdraw the ships from the Register of seagoing ships of the Republic of Lithuania. State shipping companies started to change old ships of age 27-30 years old, to new ones. By 2007 all timeworn bulkers were sold. Implementing requirements of the Law on Maritime Safety, Minister of Transport and Communications adopted an order, which assigned procedures for authorization of classification societies and evaluation of their activity. After the Register of seagoing ships of the Republic of Lithuania was established in 1991, only one classification society, Russian Maritime Register of Shipping, was technically supervising all ships and issuing documents required by international conventions. Later agreements with Lloyd�s Register, Bureau Veritas, Polski Rejestr Statkow were concluded, although many ships were still technically supervised by classification societies according to authorisation, granted on case by case basis. In 2005, old agreements with recognized organizations were revised and new ones signed with authorized classification societies Germanischer Lloyd, American Bureau of Shipping, Polski Rejestr Statkow. Pursuant to the requirements of the Directive 94/57/EC authorized classification societies are monitored at least on a biannual basis. This activity also gave positive results, improving ships� technical safety. On July 1st 2006 amendments to the Code of administrative violations of law were made, introducing fines to ship owners and masters for not complying with the requirements of international conventions on board a ship. Although these fines were criticized a lot by ship owners and masters, that was to make them more committed and contributed to enhancement of safety of ships. In 1996 when Lithuania started to apply ISM Code, since Lithuania had no appropriate administrative capacities/duly trained ISM auditors, all activities relating to verification and issuance of relevant documents were fully delegated to classification societies. At a later stage, when in close cooperation with Swedish Maritime Administration we were able to train our own ISM auditors, dependency on the work performed by classification societies in this area became less significant. At present, almost all Lithuanian flagged ships and shipping companies operating them are being certified under the provisions of the ISM Code by auditors employed in Lithuanian Maritime Safety Administration. Recognized organizations are authorised to perform verifications and issue relevant documents required by the ISM Code only on case-by-case basis. As regards the certification of Lithuanian ships under the provisions of the ISPS Code, all certification activities are performed exclusively by our own surveyors. The summary of measures, which contributed to improvement of the overall ships� technical safety level are presented in the table below.

48

Table. Measures contributing to improvement of the overall ships� technical safety level

No. Measure Date of application Result achieved

1. Accession to main IMO conventions 1991 Better regulation of maritime safety, which resulted in

improvement of overall ships� technical safety level.

2. Membership in IMO 1995 Possibility to participate in formation of maritime safety policy. Possibility to benefit from technical co-operation.

3. Adoption of Maritime Safety law 2000

A legal basis for adoption of more detailed national requirements relating to maritime safety and prevention of pollution by ships was created

4. Establishment of Lithuanian Maritime Safety Administration

2002

Establishment of Lithuanian Maritime Safety Administration enabled Lithuania to perform Port State Control in ports of Lithuania more effectively. Due actions were taken in order to become EU and Paris MoU member.

5.

Alignment of national maritime safety legislation with EU Legislation

continuous General improvement of maritime safety

6.

Establishment of agreements with RO�s in accordance with EU requirements

2005-2008

All Class agreements governing inspection, survey and statutory certification services for vessels registered in the register of sea-going ships� of the Republic of Lithuania with respective classification societies (Recognized Organizations) were renegotiated. Two new recognized organizations were authorized to act on behalf of Lithuania (RINA and ABS)

7. Supervision of RO�s, authorised by LMSA from 2004 Activities of RO�s are being closely monitored. Activities

of all RO�s are being assessed on biannual basis.

8. Performance of ISM audits by LMSA inspectors

from 2006 Enables LMSA to control the technical condition of each Lithuanian seagoing ship and RO performance as well.

Projects financed (co-financed) by the EU

1.

PHARE Project LT0005-01 �Maritime Safety and Development of a Port Information System� (Finnish and Swedish maritime administrations).

2001-2003

Finnish and Swedish maritime administrations have been involved in this Twinning project, with the aim of enhancing administrative capacities of Lithuania to meet EU requirements. This 2 year Project was aimed to establish Port information system (PIS), in order to facilitate collection, storage and exchange of information available in order to minimise dangers for human life at sea and for marine environment, and to facilitate Search and Rescue, as well as through port State inspection, eliminate substandard shipping.

2.

Project �Strengthening Maritime Safety in Lithuania� in cooperation with European Institute (Denmark) and Ministry of Transport and Communications of the Republic

2003

The overall objective of the project was to assist the Lithuanian authorities in transposing and enforcing the EU acquis related to maritime safety in particular to: �� the remaining areas as highlighted in the

Commission Regular Report on Lithuania's Progress Towards Accession from October 2002 and

49

No. Measure Date of application Result achieved

of Lithuania implemented the project

�� the new proposals from the Commission as a consequence of the conclusion in the European Council in Copenhagen on December 2002 � due to, among others, the accident of the oil tanker Prestige.

The project included the following components: �� Strengthening administrative capacity for drafting

legislation; �� The EU maritime negotiations and co-operation

process; �� Port State Control (PSC) and Flag State Control

(FSC); �� Safety of navigation in Lithuanian waters; �� Fishing vessels.

3.

Twinning Light project �Further strengthening of administrative capacity of the Lithuanian Maritime Safety Administration� (in co-operation with Swedish Maritime Administration)

2007

The project delivered the following results: LMSA personnel (3 PSC officers) are trained on specific PSC duties -inspection of specific types of ships Efficiency of inspection of foreign ships (especially tankers) in Lithuanian ports enhanced. LMSA personnel (approx. 12 persons) were trained on specific issues as regards implementation of EU maritime safety legislation.

4. Conclusions 1. Although there is certain lack of exhaustive list of criteria or ultimate methodology

enabling us to determine the safety level of certain flags over a period of time, some indicators such as the decreasing accident rate, decreasing number of very serious casualties, decreasing number of detentions of Lithuanian flagged ships after Port State Control in foreign ports due to non-compliance with applicable international standards clearly indicates improvement of general safety level of Lithuanian flagged ships over the period from 1990 when Lithuania regained its independence.

2. National authorities took a number of actions in order to ensure effective implementation and enforcement of international maritime safety and pollution prevention requirements on ships flying the flag of Lithuania. Amongst these actions one could name membership in the International Maritime Organization, ratification/accession to most IMO conventions, establishment of national maritime administration, rigorous supervision of recognized organizations, implementation of relevant EU standards and requirements, membership in Paris MoU. The entirety of these activities had a positive effect on technical condition and general safety level of the Lithuanian fleet.

3. Although many of the actions performed by national authorities were not targeting technical safety of ships as such, positive effect caused by these actions on general ship safety level of Lithuanian fleet can hardly be denied.

50

4. Actions taken by national authorities� cover a period of 16 years: from accession to major IMO conventions to full membership in Paris MoU. Other post-Soviet countries were facing similar challenges as well. Lithuania coped with these challenges quite well, therefore, we believe that on the basis of our experience or example of �good practice� a comprehensive set of actions could be developed allowing other countries, facing similar challenges to develop their own national policy aiming to effectively implement and enforce relevant international standards so that the general safety level of their fleet would be enhanced.

References 1. Česnauskis M., Tarasevičius R., Analysis of statistics and investigations of

marine casualties, registered in Lithuanian competent authorities during the period of 1999-2003m. (Jūrų laivų avarijų, įregistruotų 1999-2003m. Lietuvos kompetentingose institucijose, statistikos ir tyrimų analizė). Sea & Environment, Vol 2, Klaipėda, 2004, p. 33-40 (in Lithuanian).

2. Annual Reports (2000-2006). Paris Memorandum of Undesrstanding on Port State Control, 2006.

3. Web page of Lithuanian Maritime Safety Administration, www.msa.lt.

51

Survivability of Ro-Ro Ships in Damage Condition

Maciej Pawłowski Gdansk University of Technology, Poland

mpawlow@pg.gda.pl

Jan Jankowski Polish Register of Shipping, Gdańsk, Poland

Jan.Jankowski@prs.pl

Andrzej Laskowski Polish Register of Shipping, Gdansk, Poland

A.Laskowski@prs.pl

Abstract The paper discusses new ideas of improving ro-ro passenger ship�s safety in the damage condition, presented in [1]. Numerical motion simulations of damaged passenger ro-ro vessel in irregular waves for different positions of its mass centre and for different side casing give grounds for discussion.

1. Introduction Roll-on/roll-off (ro�ro) ships are considered by maritime experts and those involved in transport as the most unsafe ships in operation. This is not surprising considering their very low subdivision indices, usually far below the required values. This stems from the fact that these ships were most often designed according to rules obsolete today but at the time binding rules based on the factorial system, which shows little concern for damage stability. The large open vehicle decks of ro�ro vessels make them particularly susceptible to the presence of water on deck, which may appear due to collision related damage or other incidental operations, such as fire-fighting, intake of water in result of bow door being left open or its loss. Water on the vehicle deck can also appear with the damage of the ship�s side resulting from a collision. This clearly illustrates the potentially devastating influence of an open deck on the damage stability of a ro�ro vessel. In the absence of transverse subdivision, even a very small amount of water on such a deck can lead to rapid heeling and loss of stability, usually associated with a large loss of life. A question here arises as to whether we are then faced with the necessity of abandoning such an operationally efficient concept of sea transport in the pursuit of higher safety standards. Fortunately, there are alternative design configurations that may provide the necessary improvements in safety standards without causing the obvious operational consequences imposed by subdivision of the open deck, which are discussed thoroughly in reference [1]. This paper aims to show how the application of double sides (side casings) on the vehicle deck of an existing Polish ferry affects her safety in the damage condition [2].

52

2. Current subdivision arrangement of ro�ro ships Operation of cargo ships and passenger ferries with no transverse watertight bulkheads within cargo space, intended primarily for the carriage of roll-on/roll-off cargo, can be noted for some fifty years. They usually have the following watertight compartments: double bottom, forepeak, afterpeak, engine room and wing tanks. The fore and aft collision bulkheads, wing tanks and other transverse bulkheads are terminated as a rule at the bulkhead deck�the first deck above the deepest load line, also called the vehicle deck. Before 1 February 1992 there were no subdivision requirements for cargo ro�ro ships. That is why wing tanks on such ships were applied as ballasting means, frequently more for psychological reasons rather than subdivision considerations. They could save the ship only in cases of shallow damage in one of those tanks. There are cases of car-passenger ferries (of ro�ro type) which are subject to subdivision and damage stability requirements stipulated in the 1974 SOLAS Convention. Transverse bulkheads, extending from side to side usually densely subdivide space below the bulkhead deck on such ferries. In such a case, wing tanks are not applied and many of the compartments below the bulkhead deck are neither used for the carriage of cargo nor for other purposes, they are simply empty. This is a typical subdivision arrangement for most existing ro�ro ferries, such as the Polish ferry, whose subdivision arrangement is shown in Fig 1.

Fig 1. A typical but ineffective subdivision found on large ro�ro ships,

following SOLAS Convention

On the remaining ro�ro passenger ships, compartments of breadth B/5 are designed below the bulkhead deck, which are relatively short and cross-connected to avoid asymmetrical flooding. This type of subdivision arrangement is shown in Fig. 2.

Fig. 2. A typical but extremely dangerous subdivision found

on large ro�ro ships, following Resolution A.265

53

The above solutions do not provide sufficient safety for passengers of ro�ro ships in case of collision. On the contrary, these solutions appear to be extremely dangerous, as they do not protect a ferry against rapid capsizing in the case of seawater accidentally entering the bulkhead (vehicle) deck. Good evidence of the above was the tragic capsizing of the European Gateway in 1982, the Herald of Free Enterprise in 1987, and the Estonia in 1995. The three ships had the same type of subdivision, following the SOLAS Convention and shown in Fig. 1, where the ship, due to low freeboard, is densely subdivided with transverse bulkheads below the bulkhead deck in order to get one compartment standard, with no reserve of buoyancy above it. As the compartments are then very short, the probability of flooding more than one compartment is high, resulting in very low survivability of such ships and thus objectively confirming their poor performance in case of collision. In addition, the dense subdivision causes the machinery space to be divided into smaller watertight compartments and this in turn opens up an area for human error. A good example of this illusory subdivision was demonstrated by the sinking of the European Gateway [3]. The ship suffered minor damage below the bulkhead deck between the bulkheads of the machinery part of the ship. Instead of surviving this potentially typical low risk damage, she sank very quickly (within some twenty minutes) as all watertight doors within that part of the ship were left open, leading to the flooding of four compartments instead of one. The crew undertook desperate action to close the doors but tragically failed to do so. The new probabilistic rules [4], which entered into force in February 1992, require the same level of safety for all dry cargo ships irrespective of their type. Thus, new ro�ro ships will have to be equally safe (have the same indices of subdivisions) as the remaining dry cargo ships. However, the subdivision indices for existing ro�ro ships are very low, if not marginal, frequently not exceeding even 0.1, whilst for other dry cargo ships this index value is above 0.5.

3. Provisions of safety There is no possibility whatsoever of increasing the indices of subdivision so markedly under the previously applied concept of ro�ro ship subdivision following the SOLAS convention. Therefore new ideas are needed, which are discussed in detail in reference [1]. They comprise such measures as double sides, extending from the double bottom to a deck above the bulkhead deck, a "perforated" vehicle deck, transparent for floodwater and air, eliminating multi free-surfaces and air cushions, a buoyant (double) vehicle deck, and a sheer of the vehicle deck, to keep it dry in the majority of damage cases. With these measures on newly built ships it is possible to easily achieve high indices of subdivision, well exceeding 0.90. On existing ferries the possibility of improving damage safety are very limited. The indices of subdivision could be increased through a considerable increase in freeboard or by the application of removable (retractable) transverse bulkheads in holds intended for ro�ro cargo. Such solutions are clearly contradictory to the basic operational features of ro�ro ships and should be applied only as the last resort. The most frequent measures applied on existing ferries are sponsons and side casings. The sponsons are very expensive and not particularly effective, whereas the effectiveness of the side casings is examined in the next chapter.

54

To see how double sides (side casings) on the vehicle deck improve ship stability in the damage condition, a Polish ferry of the length Lpp = 159 m, breadth B = 28 m and design draught T = 5.9 m was examined. Fig. 3 presents the positions and shape of damage openings (at midships and bow, considered separately).

7.750

7 5 °7 5 ° 14.1

50

1.85

0

8.65

0

54.400

87.10013

.750

15.1

50

159.000

hold

Fig. 3. Positions and shape of damage openings

Two types of spaces above the vehicle deck were considered, with single side and double sides. The width of the double sides equals B/10, where B is the ship breadth.

4. Simulation of Damaged Passenger Ferry in Radom Waves

4.1 Computational model and its verification To examine ferry stability in the damage condition, the ferry motions in irregular waves were simulated using a computer program developed in Polish Register of Shipping. This program is based on non-linear equations of ship motions in waves [5]. The hydrodynamic forces and moments are determined at each time step. It is assumed that the hydrodynamic forces acting on the vessel can be split into Froude-Krylov forces, diffraction and radiation forces as well as other forces, such as those induced by water on deck, the rudder and non-linear damping.

The volume of water getting on the vehicle deck through the damage opening varies in time and depends on the height between the wave surface and the level of water on deck. The volume of floodwater on deck was computed according to the method presented in [6].

Forces and moments caused by water-on-deck are obtained by integrating the hydrostatic pressure, vessel�s acceleration and by changing heights of the horizontal plane above the deck [2].

Fig.4 shows the comparison of forces due to water on deck computed using the present simplified method and a more accurate model, accounting for motion of water particles in relation to the deck, based on shallow water flow [2].

55

50 100 150 200 250 300time [s]

-100000-60000-200002000060000

100000

Mx[kNm] shallow water modelpresent model

Fig. 4. Comparison of heeling moment generated by water moving on the vehicle deck using the present method and shallow water model

Volume of water accumulated on the vehicle deck and the run of the roll angle obtained from model tests [7] and simulations with the help of the mathematical model presented here is shown in Fig.5 and 6 for the ship with single sides and midships damage.

0 100 200 300 400 500

t [s]0

2000

4000

6000

8000V [m^3] computed

measured

Fig. 5. Volume of water on the vehicle deck for the ship with single sides and midships damage

56

-20

-10

0

10

20

30

40

50

60

70

80 �

0 100 200 300 400 500

t [s]

-4 -2 0 2 4 �

[deg]

measured

computed

[m]

Fig. 6. Measured and simulated roll angle for the ship with single side damaged at midship for a given wave ζ

4.2 Evaluations of the critical stability Numerical investigations of the behaviour of the damaged ship in waves were carried out for various positions of ship�s mass centres KG, where KG is the height of mass centre above the keel, for various sea states described by significant wave height Hs and the average wave period Tz. The time of simulation was 3600 s. The forward speed of the ferry v = 0. An example of the simulation is presented in Fig.7. The draught of damaged ship in still water T = 7.15 m and corresponding freeboard Fb = 1.5 m. It results from flooding the hold through the hole in the side until the ferry reaches equilibrium. Water volume in the hold fluctuates during the ship�s motion in waves. Irregular waves were generated using the JONSWAP spectrum.

57

0 100 200 300 400

t [s]

-3

-2

-1

0

1

2

3

0 100 200 300 400

-9-8-7-6-5-4-3-2-1012345 Z [m]

0 100 200 300 400

-6-5-4-3-2-101234 �

0 100 200 300 400-20

0

20

40

60

80

�

[deg]

[deg]

[m]

Fig. 7. Motions of the ship damaged at midships: Hs = 6 m, KG = 10.15 m, ζ � wave elevation, Z � heave, Θ � pitch, Ф � roll

The outcome of simulations for the ship with single sides and midships damage is compiled in Fig. 8 for various KG values.

58

2 3 4 5 6 7significant wave height [m]

0

2

4

6

8

10

not capsized

capsized

KG = 9.15 m

2 3 4 5 6 7significant wave height [m]

0

2

4

6

8

10KG = 10.15 m

2 3 4 5 6 7significant wave height [m]

0

2

4

6

8

10KG = 11.15 m

Fig. 8. Number of capsizes for the ship with single sides and the midships damage for various KG values versus the sea severity; damage freeboard Fb = 1.5 m

The ferry with side casings on the vehicle deck did not capsize at all for the same number of simulations and the same parameters as for the ferry with single sides. Simulated roll motion and volume of water accumulated on the vehicle deck for the ferry with single and double sides is shown in Fig. 9 and 10.

t [s]

-20

0

20

40

60

80 � [deg]single side

double side

0 400 800 1200

t [s]

-3.00

-2.00

-1.00

0.00

1.00

2.00

3.00 � [m]

Fig. 9. Simulate roll motion for the ship with single and double sides, midships damage: Hs = 6 m, KG = 10.15 m, Fb = 1.5m

59

0 100 200 300 400 500 600 700 800 900 1000 1100 1200

t [s]0

1000

2000

3000

4000

5000

6000

7000 V [m^3] single side

double side

Fig. 10. Volume of water accumulated on the vehicle deck for the wave as in Fig. 9

The next cases investigated were the single and double sides above the vehicle deck and the ferry damaged at bow (the underwater part of the vessel was not damaged � Fig. 3). The simulations were carried out for a bow wave (heading angle 150o) and the results are presented in Fig. 11.

t [s]

-20

0

20

40

60

80�

single side

double side

[deg]

0 200 400 600 800 1000 1200

t [s]

-4

-2

0

2

4� [m]

Fig. 11. Roll for the ferry with single and double sides above the vehicle deck heading

angle 150û, Hs = 7 m, KG = 10.15 m, Fb = 2.75 m, v = 6 m/s

Such a wave generated the biggest relative bow motions. The ferry with double sides above the vehicle deck did not capsize in the simulation period equal to 7200s.

5. Conclusions The simplified model of water flow on the vehicle deck was applied to simulate water motion on deck in order to reduce simulation time. The comparison of this model with a more sophisticated one shows that the forces generated by water on deck differ in the models (Fig. 4 and Fig. 5), however, the character of changes is similar.

60

Based on the results and arguments presented in this paper the following conclusions can be drawn:

�� Amplitudes of oscillations in damage condition are bigger in the simulations than in the experiment. This is due to the use of a simplefied model to calculate the forces generated by water on deck. In the next step the shallow water flow on deck should be applied.

�� The simulated time to capsize is similar to that in the tests (Fig. 6). Therefore, the frequency of capsizes at simulations and experiments [7] for the damaged ferry are comparable.

The JONSWAP spectrum used in the simulations was developed for the North Sea. Therefore, there is a need to develop wave spectrum and scatter diagram (representing probabilities of occurrence of different sea states) for the Baltic Sea to enable a better prediction of ship motions in Baltic sea states. The discussion presented in chapter 1, 2 and in [1], and the comparison of simulation results for damaged ferry for the four cases considered (ferry with single and double sides in way of vehicle deck and with two different positions of damage opening) presented in chapter 4 shows that:

�� The double side in way of vehicle deck significantly improves damage stability of the ferry due to the decreasing deck breadth. The heeling moment generated by water on the vehicle deck depends approximately on the third power of the breadth of the free surface.

�� The double skin extending from the inner bottom to the second deck above the waterline (Fig. 12) increases the safety of damaged ferry as it ensures both stability and sufficient reserve buoyancy.

Fig. 12. Subdivision of a ro/ro ship based on the extended double shell concept.

61

�� Fitting the ship additionally with a buoyant deck or decks (Fig. 12) and making the double bottom height as low as possible increases damage stability.

�� Water accumulated on the vehicle deck is crucial for safety of the ferry. Therefore, the deck should be designed to allow water to pass freely down (perforated vehicle deck) to the lower holds (without access to machinery or other critical spaces).

The discussion in [1] shows that some sheer of the vehicle deck can additionally add to the improvement of damaged stability.

References 1. Pawłowski, M.: Subdivision of RO/RO ships for enhanced safety in the damaged

condition, Marine Technology, Vol. 36, No. 4, Winter 1999, pp. 194�202. 2. Jankowski, J., Warmowska, M.: Simulation of motions of damaged passenger ro-

ro ship in random waves, Technical Report No.56, Polish Register of Shipping, March 2009.

3. Spouge, J. R.: The technical investigation of the sinking of the ro�ro ferry European Gateway, RINA Transactions, vol.128, 1986, pp 49�72; also in: The Naval Architect, March 1986, ibid.

4. Resolution MSC 19(58) on the adoption of amendments to the 1974 SOLAS Convention regarding subdivision and damage stability of dry cargo ships, London, 1990, pp 13.

5. Jankowski, J.: Ship facing the waves, Technical Report No. 52, Polish Register of Shipping, 2007 (in Polish).

6. Pawłowski, M.: Subdivision and damage stability of ships, 2004, Euro-MTEC book series, Foundation for the Promotion of Maritime Industry, Gdansk, ISBN 83-919488-6-2, pp 311.

7. Dudziak, I., Pawłowski, M., Błocki, W., Grzybowski, P., The stability criteria for passenger ro-ro ship in damage condition with water on vehicle deck, Technical Report No. RH-99/T-134, Ship Research and Design Centre, 1999 (in Polish).

Acknowledgment Originally published in Marine Technology, Vol. 36. No 4, Fall 1999, pp. 194-202 Reprinted with the permission of the Society of Naval Architects and Marine Engineers (SNAME)

Marine Technology, Vol. 36, No. 4, Fall 1999, pp. 194�202.

194 FALL 1999 0025-3316/99/3604-0194$00.43/0 MARINE TECHNOLOGY

*

Maciej Pawłowski1

The paper shows that RO/RO ships can be as safe in the damaged condition as other ship types without restricting their design features, i.e., with no transverse and/or horizontal subdivision within the cargo space liable to damage, if there are provisions for reserve buoyancy above the vehicle deck � the first deck above the deepest waterline. For this purpose, these ships should embody a double hull over the entire length of the cargo part of the ship, terminated at the second deck above the waterline and, in addition, double decks at least the first deck above the waterline, preferably inclined upwards in the longitudinal direction. The double hull and double decks should be sufficiently densely subdivided by watertight bulkheads into water-tight compartments, the former preferably cross-connected and of a breadth less than B/5. Cargo spaces below the double decks should be provided with efficient air escapes for removing air cushions from the undersides of the decks. A deck (or decks) if any, below the first deck above the waterline, along with this deck should be designed as opened to the passage of flooding water, incorporating efficient down-flooding arrangements.

Introduction Roll-on/roll-off (RO/RO) ships are considered by the mari-

time profession and travelling public as the most unsafe ships in operation. This is not surprising when one considers their very low indices of subdivision, usually far below the required values. This comes from the fact that these ships were often poorly designed with little or no concern for damaged stabil-ity. The large open vehicle decks of RO/RO vessels make them particularly sensitive to the presence of water on such decks which may appear there due to collision damage or other accidental operational reasons, such as fire-fighting, in-take of water due to the bow door being left open (as in the case of the Herald of Free Enterprise), or leakage of water through the aft door deprived of weathertightness, as was most likely in the case of the Jan Heweliusz, a Polish ferry which capsized in January 1993 during extremely heavy weather, causing the death of 55 passengers and crew members, with only nine persons rescued.

These two disasters clearly illustrate the potentially devastat-ing influence of an open deck on the damaged stability of a RO/RO vessel. In the absence of transverse subdivision, even a very small amount of water on such a deck can lead to rapid heeling and loss of stability, usually associated with a large loss of life.

Here arises the question as to whether we are faced then with the necessity of abandoning such an operationally efficient concept of sea transport in the pursuit of higher safety stan-dards. Fortunately, there are alternative design configurations that may provide the necessary improvements in safety stan-

dards without incurring the obvious operational penalties that subdivision of the open deck would impose, but there have been few studies in this area to provide any firm guidance.

This paper aims to show how significant improvements could be achieved in the survivability of existing and future RO/RO vessels, without impairing their present successful operational features. There are feasible solutions to the associ-ated design problems, the principles of which may be applied to car and cargo RO/RO ferries and vessels of every shape, size and description. These solutions are considerably more tangible than warning lights or video cameras focused on bow and stern doors in a bid to ensure that they are firmly closed! They are entirely based on new design configurations, provid-ing RO/RO ships with a high level of passive (built-in) safety, easily meeting the new requirements concerning ship surviv-ability, based on the probabilistic concept.

Current subdivision arrangement of RO/RO ships

For some forty years there have been cargo ships and pas-senger ferries having no transverse watertight bulkheads within cargo space, intended primarily for the carriage of roll-on/roll-off cargo. They have usually the following watertight compartments: double bottom, forepeak, afterpeak, engine room and wing tanks. The fore and aft collision bulkheads, wing tanks and other transverse bulkheads are terminated as a rule at the bulkhead deck � the first deck above the deepest load line, called also the vehicle (car) deck.

Until 1 February 1992 there were no subdivision require-ments for cargo RO/RO ships. That is why wing tanks on such ships were applied with ballasting in view and frequently due to psychological reasons rather than due to subdivision con-siderations. They could save the ship only in cases of shallow damage in one of those tanks.

There are known car-passenger ferries (of RO/RO type), they are subject to subdivision and damage stability require-ments contained in the 1974 SOLAS Convention. Transverse bulkheads, extending from side to side usually densely subdi-vide space below the bulkhead deck on such ferries. In such a case, wing tanks are not applied and many of the compart-

����������������� * The paper has been edited at The Ship Design and Research Center in

Gdańsk as Technical Bulletin (Zeszyty Problemowe), No. B�066, September1995. Progress papers were presented at: Proceedings, 12th InternationalConference and Exhibition on Marine Transport using Roll-on/Roll-offMethods � RO/RO '94, Göteborg, April 1994, Vol.2, 13 pp.; Polish MaritimeResearch, No 1, September 1994, Vol. 1, p.7�12; Proceedings, 5th Interna-tional Conference on Stability of Ships and Ocean Vehicles � STAB '94,Florida Institute of Technology, November 1994, Melbourne, Florida, Vol.6(Discussions); The Naval Architect, April 1995, p. E198, and E201�203.

1 Technical University of Gdańsk, Poland.

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FALL 1999 MARINE TECHNOLOGY 195

ments below the bulkhead deck are neither used for the car-riage of cargo nor for other purposes. On the remaining RO/RO passenger ships, compartments of breadth B/5 are ap-plied below the bulkhead deck, which are relatively short and cross-connected to avoid asymmetrical flooding. This type of subdivision arrangement is shown in Figure 1.

The above solutions do not provide sufficient safety for pas-senger RO/RO ships in case of collision. On the contrary, these solutions appear to be extremely dangerous as they do not secure a ferry against a rapid capsize in the case of sea water accidentally entering the bulkhead deck. A good evi-dence for this was the tragic capsizing of the European Gate-way in 1982, the Herald of Free Enterprise in 1987, and the Estonia in 1995, to mention only three renowned recent disas-ters.

The three ships had the same type of subdivision, derived from the SOLAS Convention, where the ship due to low free-board, is densely subdivided with transverse bulkheads below the bulkhead deck in order to get one compartment standard and with no reserve of buoyancy above it. As the compart-ments are then very short, probability of flooding more than one compartment is therefore high, resulting in very low prob-abilities of surviving for such ships and thus objectively con-firming their bad performance in case of collision. In addition, the dense subdivision causes the machinery space to be di-vided into smaller watertight compartments and this in turn opens up an area for human error.

A good example of this illusory subdivision was demon-strated by the sinking of the European Gateway [1]. The ship received a small damage below the bulkhead deck but between the bulkheads of the machinery part of the ship. Instead of surviving this potentially safe standard case of damage, she sank very quickly (within some twenty minutes) as all water-tight doors within that part of the ship were left open, leading to the flooding of four compartments instead of one. The crew undertook desperate action to close the doors but tragically failed to do so.

The new probabilistic rules [2], which entered into force in February 1992, require the same level of safety for all dry cargo ships irrespective of their type. Thus new RO/RO ships will have to be equally safe (have the same indices of subdivi-sions) as the remaining dry cargo ships. The indices of subdi-vision for existing RO/RO ships are very low, if not marginal, frequently not exceeding a value of 0.1 whilst for other dry cargo ships this index value is above 0.5. There is no possibil-ity whatsoever of increasing the indices of subdivision so markedly within the currently applied concept of RO/RO ship

subdivision, except through a considerable increase in free-board or by the application of removable transverse bulkheads in holds intended for RO/RO cargo. Such solutions are clearly contradictory to the basic operational features of RO/RO ships and should be applied only in the last resort.

Provision of double hull and deep sinkage after flooding

A feasible and efficient remedy for the poor safety of RO/RO ships is application of the idea of deep sinkage after flooding, presented in detail in [3], and briefly summarized here. It stems simply from the fact that the damaged stability of a RO/RO ship with its bulkhead deck immersed, which is a typical case, increases the deeper the ship sinks. This startling observation is not difficult to explain. An increase in damaged draught for any constant damaged displacement allows the center of buoyancy to move closer to the center of gravity, thereby improving stability. Moreover, experiments have shown that in ships with the much deeper draught associated with the final stage of flooding, any roll motion in waves al-most completely disappears so that only heave motion re-mains. It is therefore very unlikely that such a vessel would be capsized by wave action when it is floating deeply immersed in a near upright position.

In the light of the above remarks an increase in the number of bulkheads below the vehicle deck is found to reduce dam-aged stability dramatically. This situation is opposite to that for conventional ships and is confirmed by model tests [4]. It is evident from the foregoing that the primary safety feature for a RO/RO vessel should be a mandatory double skin ex-tending from the inner bottom to the second deck above the waterline (the upper deck). The wing compartments so formed should be transversely subdivided throughout and incorporate modest flare, if possible.

Apart from this the number of transverse bulkheads should be limited to the forward and aft peak bulkheads and those required to adequately subdivide the non-vehicular spaces such as the machinery spaces. The strength of these bulkheads should, of course, be adequate for the pressure loads imposed by the deep draught in a damaged condition. No further trans-verse bulkheads should be provided, as the wing compart-ments replace their function.

This type of subdivision arrangement is shown in Figure 2. The breadth of the wing tanks equals preferably B/10, half as large as in the previous case. As such RO/RO vessels are ca-pable, as a rule, of surviving a major flooding, at least in a partial loading condition. In such a case, there is no need to

Figure 1. A typical but extremely dangerous subdivision found on

large RO/RO ships, influenced by the SOLAS Convention.

Figure 2. A typical subdivision arrangement for RO/RO ships

based on the concept of deep-sinkage-after-flooding.

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FALL 1999 MARINE TECHNOLOGY 196

increase the height of the double bottom. On the contrary, from the standpoint of damage stability, the minimum height is preferable.

To limit the effects of flooding, the wing compartments should be relatively short, identically subdivided on both sides and cross-connected to prevent asymmetric flooding, which is always detrimental to a ship in a damaged condition. In the case of passenger RO/RO vessels, the current SOLAS regula-tions require that lower wing compartments should have a breadth of not less than B/5 and no wing tanks above the bulk-head deck, as shown Figure 1.

If one assumes that major flooding of inboard spaces repre-sents the loss of a RO/RO ship then it would be necessary to require, for ship safety, the wing compartments below the car deck to be as wide as possible to minimize the risk of such a possibility. However, that is not the case and, therefore, there is no need to impose such broad wing compartments in this position.

To withstand major flooding, it is most important for a RO/RO ship to ensure positive stability at the final stage of the event when the bulkhead deck is immersed. It has been shown that this is quite practicable and requires only that narrow wing compartments be fitted below and above the vehicle deck, as shown in Figure 2, to ensure both stability and suffi-cient reserve of buoyancy. Such is the purpose of providing these wing compartments.

Merit of a double skin

Wing compartments on RO/RO ships can fulfil many other important functions: � They greatly enhance the ability of the ship's sides to absorb

the energy of a collision, thereby decreasing the extent of damage, while also increasing the resistance to breaching during minor collisions.

� They provide a positive contribution to the vessel's overall strength.

� They provide essential trimming ballast capacity in the lower hull.

� They contribute directly to improved damaged stability. � Their smooth sides make cargo handling easier in the holds. � They effectively protect the ship against the effects of leak-age due to cracks or small breaches of the shell.

Intermediate stages of flooding

Thus far stability during the intermediate stages of flooding has not attracted the attention it deserves. Work done to date supports the intuitive notion that the intermediate conditions are not usually a problem if the final condition is acceptable, provided that the angle of heel is not so large as to cause cargo shift and the flooded water can freely spread over the entire compartment. The deck edge then remains above the water all the time during transient flooding [5].

The same applies also for RO/RO vessels with double skin arrangement provided that the decks are made opened to the flooded water, which is crucial for the safety of these ships.

Thus if there are efficient down- or cross-flooding arrange-ments, it is entirely sufficient as far as damaged stability is concerned to check only the maximum angle of equilibrium during flooding, and focus attention on the safety of the ship in the final stage of flooding. Hence, the above theoretical devel-opment has a considerable impact on the simplification in damaged stability assessments.

Owing to physical reasons, stability during the intermediate stages of flooding should be analyzed for the freely floating ship longitudinally balanced at each angle of heel, using the added mass method. There are usually marked differences between the GZ-curves calculated for the free trim condition and for fixed trim, particularly if the deck edge becomes im-mersed and the ship has large longitudinal asymmetry. How-ever, in the case of horizontal subdivision without efficient down-flooding arrangements, it should be assumed that after the immersion of the edge of the watertight deck, the level of water above such a deck coincides with the level of water out-side. This covers the case of a small hole below and a very large one above the horizontal subdivision, a typical damage when the striking ship has a bulbous bow associated with a large flare � see the case of the European Gateway [1].

The current regulations [2] overlook totally this problem. This is one reason why naval architects consider horizontal subdivision, especially on RO/RO ships, as beneficial to their safety. Unfortunately, this is not the case and it is now high time to tell this loudly and clearly in an attempt to divert the way things are developing.

Perforated vehicle decks

An important point on all RO/RO vessels concerns the wa-tertight integrity of the main and other vehicle deck, that is, the presence of horizontal subdivision. From the previous dis-cussion, it should be clear that any deck, including the vehicle deck, which may suffer flooding from whatever source, should be non-watertight. Furthermore, such decks should be de-signed to allow both water and air to pass freely through them.

How this should be accomplished in practice is an interesting challenge for the designer. The drainage systems must be ca-pable of allowing very large quantities of water to drain di-rectly into the lower cargo spaces without access to machinery or other critical spaces, which must be effectively sealed from the cargo spaces at all times. This has the effect of maximizing the damaged metacentric height by both eliminating isolated free water surfaces and lowering the center of gravity.

Watertight vehicle or tweendecks cannot be recommended for the following reasons: � Decks below the vehicle deck are not usually designed to

withstand the pressure forces that would be imposed by se-rious flooding either above or below them.

� When flooding occurs above such a deck, a large free water surface is formed which immediately reduces the vessel�s metacentric height, usually causing a large angle of heel or capsizing.

� These decks can trap large quantities of air beneath them during sinkage, maintaining an additional free surface ef-fect, which would be eliminated if the compartment were free to fill completely. In addition, these air cushions con-tribute to the creation of an additional heeling moment of significant value as they are formed usually at the outmost areas beneath the decks close to the side opposite to dam-age. As a result, these air cushions are extremely dangerous and lead to the capsizing of the ship, otherwise safe, before reaching the final stage of flooding.

� Watertight ramps and decks are more expensive than their non-watertight counterparts.

In view of these points, there seems no good reason to retain the concepts of either horizontal or vertical watertight subdivi-sion applied to internal vehicle spaces. In particular, retaining the vehicle deck as a bulkhead deck is particularly dangerous and should be abandoned as a design objective.

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There are two further reasons why the bulkhead deck within the cargo space should be made transparent to the flooded water. Such a deck virtually eliminates the accumulation of the flooded water above this deck due to the action of waves which is found to be dangerous and it leads eventually to cap-size [6�8]. Due to a very similar reason, the watertight deck is also detrimental to stability during the intermediate stages of flooding which is rarely analyzed during designing and over-looked by the current regulations.

The idea of deep sinkage was implemented at Gdańsk Ship-yard, Poland, by designing a passenger-freight RO/RO vessel of 12 000 DWT, with the overall length of 183 m, based on the double hull arrangement, as shown in Figure 2. The bulkhead deck was designed, however, as watertight thus only partly fulfilling the necessary requirements for a really safe RO/RO vessel. To make this deck open to the passage of water ap-peared to be too challenging for the designers.

Provision of buoyant decks It is difficult to achieve deep sinkage after flooding on real

RO/RO ships due to the large longitudinal unbalance between the aft part containing the machinery room and the forepeak. As a result, the ship assumes after flooding an extremely large trim by the bow that is not as beneficial to damaged ship safety as deep sinkage on an even keel. It is worth considering, therefore, fitting the ship additionally with a buoyant deck or decks, at least the bulkhead deck, transversely and longitudi-nally subdivided by watertight bulkheads � see Figure 3.

As previously, cargo spaces should be provided with effi-cient air-escapes (vents) placed at the sides, close to the top of cargo spaces, to eliminate detrimental air cushions that may occur during flooding. The breadth of the double sides is defi-nitely less than B/5; they should be subdivided into wing tanks by transverse bulkheads and be preferably cross-connected. The height of the double decks is preferably not greater than the depth of deck girders for relevant single decks. The double bottom should be preferably of the minimum height required by classification rules [9].

The bulkhead deck and a deck below, if any, should be de-signed as permeable (transparent) for the flooded water to en-sure free flooding, i.e., uniform spread of water over the whole compartment during transient flooding. With the provision of buoyant decks, sinkage after flooding is obviously reduced and, in the extreme, can be as small as to keep the bulkhead deck emerged.

RO/RO ships, in general, have deep deck girders because of the large unsupported deck spans. In view of the problem of cargo handling, stowage is usually restricted to spaces below the flanges of these girders. There is opportunity, therefore, to seal off the space upwards from the flanges of the deck girders to the deck plating to form a chamber (pontoon) that can pro-vide additional buoyancy and depending on its location, height and extent, be of some advantage in terms of damage surviv-ability.

The problem of locating this buoyant deck is a fairly in-volved exercise. However, it can be shown that for such a buoyant deck with a displacement of v the stability coefficient will be increased, if the buoyant deck is located at a height Hdeck satisfying the relation

Vi

VJTH damdeck

�

��

�

���

where Tdam is draught in the damaged condition without the buoyant deck, whereas �J and �i are change in the moments of inertia of the undamaged waterplane and the free surface of the water due to change in displacement of �V = v caused by fitting the buoyant deck.

Because �i � 0 if the vehicle deck remains submerged and �J /�V is positive then it is practically impossible to satisfy the above inequality unless there is a large reduction in the free surface moment of inertia due to partial emergence of the buoyant deck. Unless this inequality can be satisfied, a buoy-ant vehicle deck will have a nearly neutral effect on initial stability in the flooded condition and consequently on the ship safety. Even though effective increase in freeboard, due to the provision of the buoyant deck, increases stability at large an-gles of heel, it is rather unlikely that this will be of much prac-tical benefit in ship survival except in situations when the an-gles of flooding are very small.

However, it is not difficult to design for significant reduc-tions in the free surface moment of inertia. This is because in the majority of damage cases there will be a trim by the bow due to the comparatively large machinery space. In appropriate combinations of buoyant vehicle deck and wing spaces, a situation may be reached that for a large number of damage cases the next higher deck comes into contact with the flooded water.

If this higher deck is also made buoyant in the forward part of the ship, a significant gain in the index A value may be ob-tained and an advantage from utilization of spaces that are usually non-productive anyway from the cargo carriage point of view. Another possibility is to use a buoyant vehicle deck that is slightly inclined upwards in the longitudinal direction so that after damage the entire deck continues to remain above water in spite of the bow trim. Moreover, active consideration might be given to designing the forward upper part of a RO/RO cargo ship as a rectangular box, like in an aircraft car-rier [10], to improve matters further in cases of deep sinkage after flooding.

The effect of a buoyant bulkhead deck is relatively modest in the cases where the deck is chosen with no concern regarding the reduction of free surface. It can be of the order of a 5% increase in index A values [11]. The improvement, obviously, may be considerably greater, if multiple buoyant decks are used, as may be feasible in some RO/RO vessels, or �particularly � when the vehicle deck is inclined and remains above water in the majority of damage scenarios.

Figure 3. Subdivision of a RO/RO ship based on the extended double shell concept.

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FALL 1999 MARINE TECHNOLOGY 198

Benefits of novel subdivision

The benefits of a subdivision arrangement based on the ex-tended double shell concept are twofold: From the design and operation standpoints: � It is possible to obtain high indices of subdivision for

RO/RO ships required by the new subdivision regulations, without impairing their successful operational features, based on non-subdivided horizontal cargo spaces;

From the technical standpoint: � The cargo space is not reduced. The double decks make use

of the space on the underside of single decks, contained be-tween the huge deck girders, useless for cargo anyway. Con-finement of this space by relatively thin watertight shell plating, replacing the thick flanges of deck girders, converts this inefficient space into a double buoyant deck of consid-erable volume, reducing bow trim after flooding;

� The weight of the ship is only marginally increased thus nearly the same dead-weight is maintained;

� Overall ship and deck strength is improved; � Smooth sides make cargo handling and insulation works easier.

It can be expected, therefore, that overall building time and thus the cost of ship production may be eventually somewhat reduced for such ships.

Numerical examples

To see how this concept works, a RO/RO ship designed at the Gdańsk Shipyard was examined, whose main particulars were as follows:

Subdivision/overall length .............................. 177,50/183.00 m Length between perpendiculars .................................. 171.30 m Breadth, molded ........................................................... 28.70 m Depth, to main/upper deck.................................... 8.90/15.23 m Depth, to weather deck ....................................... 21.20/23.10 m Draught T, design/scantling ................................... 6.80/7.40 m Supply/water ballast tanks ................................... 1880/9500 m3 Dead-weight at scantling draught .................................. 12400 t Breadth of wing tanks..................................................... 2.80 m KG for full load condition at T = 7.40 m ...................... 13.65 m KG for partial load condition at T = 6.11 m ................. 13.67 m Permeability � ......................................................................0.80 Required subdivision index R value ..................................0.545

Example 1: The ship with a subdivision arrangement as in Figure 2, with no cross-flooding, deck No 3 (upper deck) wa-tertight which is not realistic in this case. For such a ship the attained subdivision index is much below the required one and equals A = 0.5132.

Example 2: The ship as above but with cross-flooding. The index is then A = 0.581. As can be seen, cross-flooding caused a significant increase in the index value here. It should be as-sumed as a rule that cross-flooding is always beneficial for ship safety and, therefore, it should be applied whenever pos-sible.

Example 3: The ship as in Example 2 but with Deck 3 treated as non-watertight which is in compliance with the ac-tual design. The attained index value is now much lower and equals A = 0.512, which should obviously be expected. It is then quite sensible to make the upper deck watertight, if pos-

2 The indices of subdivision were calculated according to [2].

sible. Moreover, as the ship has typically a large bow trim after flooding and thus small angles of flooding, active consid-eration might be given to a deck or decks made buoyant at the forward end, to increase the height of openings above the damage waterline, thereby improving stability.

Example 4: The ship as in Example 3 but with Deck 2 as a pontoon, creating a buoyant double deck of 1600 mm depth as shown in Figure 3. The attained index value is now A = 0.519, which is only marginally higher than in the previous case. This is because the buoyant deck as it is, due to the bow trim, in the majority of damage scenarios, still remains under water over the majority of its length, thus insignificantly contributing to the reduction of the free surface effect.

This example provides a good lesson: not every buoyant deck can be expected to contribute significantly to ship safety. To do so, the whole subdivision arrangement must be carefully chosen so that the buoyant deck could remain above the water in prevailing cases of flooding.

It is not difficult to do so. Keeping the remaining subdivision unchanged, there are two immediate possibilities: a slight in-crease of the height of Deck 2 maintaining the underside struc-ture of the deck with the original depth which is equivalent to an increase of the pontoon depth by the same value; and/or a slight inclination upwards in the longitudinal direction of the topside of the deck. The application of medium-speed engines for ship propulsion provides another possibility if such engines are located in the wing compartments, then the lower cargo hold can be significantly extended aft thus largely reducing bow trim after flooding.

Example 5: The ship as in Example 4 but with the ship's depth to Deck 2 increased by 0.2 m from 8.9 to 9.1 m. The depth of the pontoon is simultaneously increased from 1600 to 1800 mm, keeping the underside structure of the deck at the previous height. The attained index is now A = 0.556, which is higher than the required value R = 0.545.

It is worth noting the incredible increase of the index due to the increase of the depth to Deck 2 by only 0.2 m. This exam-ple shows how sensitive ship safety is to some parameters of subdivision arrangement containing a buoyant deck and that is why it is so easy to be disappointed with it, if it is not properly chosen. Most important of all is to keep, as far as practicable, the buoyant deck dry (to remain above water) in the majority of damage cases.

Example 6: The ship as in Example 5 but with Deck 2 in-clined upwards in the longitudinal direction by 1 meter in the foremost end of this deck, as shown in Figure 5. The attained index value is now A = 0.621 and it is thus drastically higher than in the previous case. Such a result should obviously be expected in the light of the previous remarks.

From the examination of some of the most representative cases of flooding for the previous case study, it followed that the depth of the flooded water at the forward end of Deck 2 did not exceed a value of 1 m. This is why in the case of the 1 m sheer of Deck 2 the free-surface effect could be reduced to nearly nothing in most cases of damage, thus markedly increasing the index value.

The rise of Deck 2 by 1 meter at its foremost end is not much. Looking at Figure 5, one can hardly believe that this deck is inclined at all. All other decks above Deck 2 must have, obviously, the same sheer, to keep them parallel to one another.

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In all the examples, Deck 2 was treated as opened for the passage of water and air, to eliminate the many adverse ef-fects, discussed above, and not accounted for in the current regulations. Owing to that reason, horizontal subdivision due to Deck 2 was simply ignored, and this was for the benefit of the ship.

Example 7: The ship as in Figure 4 with narrow double sides of B/10 at the lower hold and with an increased width of the side compartments of B/5 between the main and upper decks. Such an arrangement was eventually adopted by the Gdańsk Shipyard on the FINNHANSA � the first of four luxurious RO/RO vessels, sister ships ordered by Finncarriers. The at-tained index value is now A = 0.668, as obtained by the Ship-yard according to the regulations for passenger ships, con-tained in resolution A.265 (VIII). This value of the index, however, cannot be directly compared with the indices given in the previous examples, as they were calculated according to the regulations for dry cargo ships and the two methods are not identical. Nevertheless, the value is high and greater then the required value R = 0.578, and the Shipyard and Shipowner are very proud of it [12�15].

Such a design, however, should not be recommended for the following reasons: � The side compartments at Deck 2, intended for the carriage

of passenger cars, are subdivided by a number of transverse bulkheads fitted with watertight doors, automatically oper-

ated. Entrance and way out from these spaces is through side gates, closed by large watertight doors. Apart from be-ing very costly, unreliable and ineffective in terms of stow-age, such an arrangement is illusive regarding watertight in-tegrity of these spaces, bearing in mind the large distortions the ship can sustain at the moment of collision;

� Ventilation ducts run vertically along the outer side, starting 0.800 m below Deck 2, leaving room for progressive flood-ing of the lower hold in case of damage in way of Deck 2 or above;

� Deck 2 is not made as open for the passage of water and air so the actual stability in case of water entering the hull is much poor than that which is routinely calculated;

� Insulation of the underside structure of Deck 2 requires a large labor consumption;

� Despite the requirement, the increased height of the double bottom should not apply in this case, as the design is capable of withstanding a major flooding. A normal height should ap-ply instead, thereby improving stability.

Consequently the dead-weight of the ship is reduced by 1700 tons. Moreover, despite the apparently high value of the index, the ship is far from what can be realistically achieved whose safety is based on wishful thinking rather than on rational principles. Such an arrangement is therefore not recom-mended.

General arrangement of the above ship and its brief technical description is given in the Appendix, taken from a commercial leaflet issued by the Shipyard.

Conclusions

The probabilistic subdivision regulations for dry cargo ships [2] provide a framework for the rational assessment of com-peting RO/RO ships design from the damage survivability point of view. It is clear from the results reported above that it is possible to achieve a satisfactory subdivision index value for such ships without transverse or horizontal subdivision below the upper deck. Their intended function is replaced by narrow wing compartments extending from the inner bottom to the upper deck, cross-connected, and by a buoyant deck or decks below the upper deck, opened for the passage of water and air, leaving this deck area clear for through transport.

The judicious distribution of reserve buoyancy in the longi-tudinal, transverse and vertical directions is particularly impor-

Figure 4. A subdivision arrangement found on B501/I type combi

RO/RO built in Stocznia Gdańska

Figure 5. An example of subdivision on a large RO/RO ship based on the extended double-shell concept.

Note the 1-meter rise at the forward end of the main deck.

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tant in the design of these ships and since there are many ways of doing this satisfactorily, there is obvious scope for optimi-zation in the arrangement of such vessels. The performance of these ships in the damaged condition is very sensitive to some particulars of the subdivision arrangement containing a buoy-ant deck, depending on presence (or absence) of water on the deck in a flooded condition.

Continues and, if possible, uniform distribution of reserve buoyancy in the vertical direction is necessary for minimizing the adverse effects during transient flooding, while in the lon-gitudinal direction � due to the uniformity of survivability along the ship�s length. The latter is best measured in the form of local indices of subdivision, not yet used in the regulations. The local indices are measure of minor damage survivability, currently covered by deterministic requirements, inadequate and unfitted to the probabilistic framework.

It is important to note that the current survivability regula-tions merely set standards, though imperfectly, and are not prescriptive as regards an actual arrangement. The designer, therefore, retains the opportunity to meet the range of design objectives. Subdivision arrangement based on double hull and double deck seems to be particularly efficient and beneficial for these ships. Therefore, it may be expected to be common among future RO/RO ships. □

References

1. Spouge, J. R.: The technical investigation of the sinking of the RO/RO ferry European Gateway, RINA Transactions, vol.128, 1986, pp 49�72; also in: The Naval Architect, March 1986, ibid.

2. Resolution MSC 19(58) on the adoption of amendments to the 1974 SOLAS Convention regarding subdivision and damage stability of dry cargo ships, London, 1990, 13 pp.

3. Pawlowski, M., and Winkle, I. E.: Capsize resistance through flood-ing � a new approach to RO/RO safety, Proceedings, 9th Int. Conf. on through Transport using Roll-on/Roll-off Methods, RO/RO '88, Gothenburg, June 1988, BML, pp. 250�261.

4. Grochowalski, S., and Pawłowski, M.: The safety of RO/RO vessels in the light of the probabilistic concept for standardizing unsinkability, Inter-national Shipbuilding Progress, vol.28, No.319, March 1981, pp.63�72.

5. Pawlowski, M.: Bezpieczeństwo niezatapialnościowe statków (Safety of ships in the damaged condition), Journal of Tech. Univ. of Gdańsk Bu-downictwo Okrętowe, No. 42/392, Gdańsk 1985, 132 pp.

6. Vassalos, D.: Capsizal resistance prediction of a damaged ship in a random sea, Proceedings, RINA Symp. on RO/RO Ship's Survivability: Phase 2, RINA, London, November 1994, paper No. 2, 15 pp., also in: RINA Transactions, Vol. 138, 1995, 20 pp

7. Vassalos, D., Pawlowski, M., and Turan, O.: A theoretical investiga-tion on the capsizal resistance of passenger/RO/RO vessels and proposal of survival criteria, Final Report, Task 5, The North West European R&D Pro-ject, March 1996.

8. Vassalos, D., Pawlowski, M., and Turan, O.: Criteria for survival in damaged condition, Proceedings, RINA Int. Seminar on the Safety of Pas-senger RO/RO Vessels, RINA, London, June 1996, 15 pp. + 11 figures; also in: Dynamic stability assessment of damaged passenger RO/RO ships and proposal of rational survival criteria, Marine Technology, Vol. 34, No. 4, October 1997, pp. 241�266.

9. Pawlowski, M., and Habina, Cz.: A RO/RO vessel (Statek typu RO/RO), Polish patent No 167022 B1, published on 31.07.1995 at WUP 07/95, Warsaw, 1995. The patent is ceased.

10. Wahl, J. E.: New catamaran RO/RO design for Norwegian coastal service � a breakthrough in hull design, Proceedings, 9th Int. Conference on Through Transport using Roll-on/Roll-off Methods RO/RO '88, Gothenburg, June 1988, BML, pp.101�119.

11. Sen. P., Pawlowski. M., and Wimalsiri, W. K.: RO/RO cargo ship de-sign for enhanced survivability in the damaged condition, Proceedings, 9th Int. Symposium on Ship Hydromechanics, Gdańsk, September 1991, vol. II, 5 pp.

12. Mustamäki, E.: FG-Shipping's new Baltic combi-roros � large 3200 lane-metre ships with two-level stern access and passenger accommodation, Proceedings, 12th Int. Conference & Exhibition on Marine Transport using Roll-on/Roll-off Methods RO/RO '94, Göteborg, April 1994, Vol.2, 11 pp.

13. Boyce, J.: Finnhansa � a luxurious RO/RO vessel, Cruise & Ferry Info, No. 11/94, pp. 18�21.

14. Polish built Finnhansa leads a new class of Baltic safe/passenger ferry, The Naval Architect, January 1995, pp. E15�24.

15. Wilson, T.: Freight roros are adapted to meet route demands, Motor Ship, January 1995, pp. 12�17.

Appendix

Combi RO/RO B501/I type built by Stocznia Gdańska S.A.

Main particulars

Length, o.a. ......................................................................183.00 m Length, b.p. ......................................................................171.30 m Breadth, molded ................................................................28.70 m Depth to bulkhead deck .....................................................15.23 m Depth to weather deck .............................................21.20/23.10 m Depth to main deck ..............................................................8.90 m Scantling draught .................................................................7.40 m Scantling dead-weight........................................................10,700 t Design draught..................................................................... 6.80m Design dead-weight .............................................................8,500 t Car lanes (width 2.85 m) ....................................................3,200 m Trial speed ..........................................................................21.3 kn Crew berths................................................................................ 23 Passenger berths....................................................................... 112

Tank capacities:

Heavy fuel oil .................................................................. 1,450 m3 Diesel oil ............................................................................. 350 m3 Lubricating oil ...................................................................... 60 m3 Fresh water.......................................................................... 250 m3 Water ballast .................................................................. 10,000 m3 Antiheeling, stabilizing tanks........................................... 1,050 m3

Type of vessel

Innovative, highly automated, multi-purpose, double skinned, ice strengthened Baltic combi RO/RO carrier, designed for car-riage of passengers and cargoes such as paper, timber products, roll trailers, transflats, containers, cars, lorries, chilled fruit in the lowest hold; 93 TEU can be carried on the fourth deck; the vessel is designed for future installation of about 510 m of railway tracks on the second deck; twin propeller vessel with twin skeg transom stern, raked stern, bulbous bow, two bow and two stern thrusters, four cargo decks, all cargo decks free of any pillars, five tier superstructure, two high lift Jastram type rudders; fitted with antiheeling and stabilizing system.

Class of vessel

Det Norske Veritas class notation �1A1 CAR FERRY A E0, Ice 1A, corr, TMON

Conventions and rules met by the design: SOLAS-74/89, IMO resolution A265 (VIII) concerning damage stability, TON-69, COLREG-72, MARPOL-73/78, LL-66, ILO-92, rules of Kiel, Suez and Panama Canal Authorities, ITU, IEC

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FALL 1999 MARINE TECHNOLOGY 201 Figure 6. General arrangement of a passenger-freight RO/RO B501/I type from the Shipyard of Gdańsk.

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and Finnish Board of Navigation Rules, dangerous cargoes ac-cording to IMDG code can be carried on the forth deck and in the open part of the third deck (Class 1, 2, 3, 4, 5, 6, 7, 8, 9), while closed Decks No. 1, 2 and 3 are restricted to few classes of dan-gerous goods.

Cargo vessel equipment

Movable ramps Two stern hydraulically operated and battened combined

ramps:

� one on the second deck, length 12.5 m, drive width 21.65 m, and height 5.30 m,

� one on the third deck, length 13.45 +3 m, drive width 9.0 m.

Fixed internal ramps � one centrally positioned internal fixed ramp between the

first and second decks (drive width 4.40 m with cover panels, drive height 4.8 m),

� one starboard internal fixed ramp between the second and third cargo decks with drive width 4.3 m,

� one portside internal fixed ramp between the third and fourth decks with drive width 4.2 m and height 4.8 m.

Engine room

Main engine Type ............................................Zgoda-Sulzer 8ZAL40S x 4

MCR ........................................... 5,760 kW at 510 rpm each SFOC .......................................... 179 g/kWh + 5% HFO viscosity ............................. 600 cSt at 50ºC Propeller...................................... two CP type Reduction gears .......................... 510/142 rpm x 2

Maneuvering gear Bow thrusters .............................. two of 900 kW each Stern thrusters ............................. two of 450 kW each (in skegs)

Boilers One vertical water-tube oil-fired auxiliary boiler of 4,000 kg/h steam capacity at 0.8 MPa, Four exhaust-gas boilers of 1,000 kg/h steam capacity at 0.8 MPa.

Accommodation

All accommodation is designed to a very high standard as on cruise passenger vessels, with single cabins for officers and crew, 24 luxurious three berth and 10 four berth cabins for passengers.

Life saving appliances

Two GRP lifeboats for 48 persons each, Two fast 20 knots rescue boats, Four 16 person inflatable life rafts, One inflatable raft for 6 persons. ■

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