THE PROJECTThis study undertakes to thoroughly review of available evidence, proposal of loss hypotheses, testing of these through first-principles tools and demonstration of the established loss scenario through physical experiments and simulations. Objectives The overall goal of the study is to understand the sequence and explain the underlying causes of the loss of MV Estonia and hence derive suitable recommendations on design and operation of passenger vessels in order to prevent such tragedy from happening again. To achieve this goal, the following specific project objectives are set:
Expected
Outcomes It is expected that this project will lead to improved understanding of the mechanisms and the underlying causes of the loss of MV Estonia and of the key contributing design and operational factors, thus providing the basis and the motivation for significant safety improvement of Ro-Ro passenger ships. Contrary to traditional naval architecture calculus, MV Estonia maintained her function of a supporting platform for over half an hour, thus allowing a number of people to save their lives. A thorough understanding of which design characteristics allowed MV Estonia to resist capsizing when subjected to large scale flooding at the level reported, would be of great help to today’s designers in their strife to make ships their own lifeboats. Bearing in mind that contemporary large passenger ships can accommodate five thousand, “plus”, persons, such “unsinkable” ship concept seems to be the only alternative to ensure safety for passengers, crew, the vessel itself and to protect the environment. This project, by bringing together a consortium with unique state-of-the-art knowledge and tools, provides an opportunity for instilling a fundamental understanding in the maritime industry at large, namely that improving ship safety requires use of knowledge in all its forms, and that only through embracing innovation and becoming more technologically adept could the rightful levels of safety be achieved cost-effectively. Rationale The loss of MV Estonia has unravelled inherent
weaknesses of ships with large undivided spaces when subject to hull damage,
and has impelled substantial revision of the ship safety regulatory regime,
with numerous recommendations for improving the stability of Ro-Ro ships
implemented regionally in the However, since the complete explanation of the circumstances and mechanisms underlying the foundering of MV Estonia have not been given to date, a number of questions pertinent to the loss, directly or indirectly relevant to the future provision of safety, still remain, namely: (a) What is the importance of all the key factors pertinent to the loss of the vessel, the fatalities, the time to sink, escape and rescue? (b) How transferable are the design characteristics, which provided the MV Estonia with stability so atypical to Ro-Ro ships, to the new generation of designs? (c) How can advances in mathematical modelling, computer simulation and assessment techniques, new technologies, IT and communication be used to design and operate safer ships cost effectively? What were the options available and the actions taken by the crew in terms of active measures to improve the stability (resistance to capsize) of the vessel? What was the role of the MV Estonia’s superstructure in preventing rapid capsizing? Can a new ship be designed cost-effectively for the MV Estonia’s-like loss scenario or indeed any feasible damage scenario? How could first-principles modelling and consequence analysis tools be implemented in routine design and operation practices? By providing a comprehensive description of all of the important details leading to the loss of MV Estonia, substantiated by state-of-the art modelling techniques and physical model testing, the proposed study will focus in answering the above and many other direct questions, thus starting a catalytic chain reaction of routine performance-based safety assessment in designing the new generation of passenger ships. And as the old proverb of safety engineers goes “safety comes down to the designer in the end”, much needed improvements to safety of life at sea will be realised. Approach The proposed approach combines a wealth of forensic, design, analytical modelling and experimentation expertise of the partners involved, deployed to scrutinize and review the available evidence, to synthesise this into loss hypotheses, to test these hypotheses through first-principles modelling studies, and to finally demonstrate the established scenario of the loss through a physical experiment and through virtual modelling and simulation. It is important to state and to realise that this consortium possesses expertise in terms of computer simulation tools and experimental techniques that is unique; without utilisation of such capability the loss of MV Estonia will remain a mystery. The official JAIC report with
its supplements, the SPF study as well as all other available material
pertinent to the ship and the accident, will form the basis for the detailed
scrutinising and reviewing study. Classification of the information, qualification
of its pertinence, validation and ultimate synthesis will follow
specialists’ expert reasoning process. The consortium team has
demonstrable and extensive experience in carrying out in-depth forensic
investigations into ship accidents, at the highest international profile
(Herald of Free Enterprise, MV Derbyshire, MV Rockness,
FV GAUL, APL The testing procedure will involve numerical modelling with state-of-the-art tools for simulation of ship manoeuvring in intact and damaged conditions and in waves, simulation of floodwater ingress, ship response with floodwater progression through the ship, simulation of the evacuation and abandoning process, and thorough assessment of effects of cargo shifting on the loss. The tools to be used are the SSRC suite of codes PROTEUS3, built on some 25 years of research and development into the field of damaged ship dynamics; the SSRC passenger/crew evacuation code EVI, gaining ground as the most advanced evacuation model available today by being developed purposely for the marine environment, the FREDYN software developed as a result of some 15 years of joint research effort between Navies of Australia, Canada, France, the Netherlands, United Kingdom, United States and U.S. Coast Guard to build a comprehensive dynamics simulation tool for intact and damaged ships in extreme conditions, and other specialist modules for the simulation of deployment of life saving appliances. SSPA will use the program SEAMAN to simulate the water ingress, the manoeuvring in wind, waves and current. SEAMAN is the result of about 20 years research on ship manoeuvring and seakeeping. The SIMCAP code is based on some 10 years of research on damaged ship dynamics at KTH and Chalmers. All the software has a documented extensive track record of successful applications to research, design, and forensic studies or for training purposes. To build relevant digital models of MV Estonia, detailed information will be required of the vessel architecture, namely hull lines including all appendages, GA and internal subdivision throughout the ship, including Decks 4 to 9, capacity to oppose flooding deriving from strength of external windows, internal doors, walls, etc, watertight doors operation, venting ducts, cargo distribution and characteristics, piping system topography and other connections. A specific model of cargo shifting reflecting characteristics of the cargo as well as the stowing systems onboard MV Estonia at the time of the loss will analysed, possibly by a subcontracted specialist, if deemed necessary. Typically, 400-500 separate spaces and 300-600 various openings need to be modelled. Some of the physical phenomena governing the dynamics of ship response are still beyond modelling with precise mathematical constructs. Whilst approximations typically adopted are sufficiently robust for traditional design practise, it is deemed necessary to carry out detailed, fundamental model experiments to derive results accurate enough for characterising qualitatively and quantitatively some of the specific factors that are known to have affected the ship loss. In particular a set of tests will be carried out by MARIN at one of the most advanced marine testing facility in the world, to quantify experimentally the rates of progression of flooding through complex geometries in accommodation spaces of MV Estonia (cabins, corridors, windows). The second set of tests will be carried out by the SSPA at their renowned Maritime Dynamics Laboratory (MDL), to quantify flooding rates for a combination of the bow doors arrangement, environment, vessel speed, heading and attitude (large heel angles). A geo-similar physical model of MV Estonia in scale of [1:40] will be built for this purpose, comprising the internal as well as the external ship architecture. Care will be taken to represent all the important internal space arrangements covering cabins, corridors, stairs, etc, as accurately as is possible. The same model will be used to perform a set of standard manoeuvring experiments, extended to manoeuvres in damaged conditions with various amounts of floodwater inside the vessel. These results will not only be used to upgrade existing models of PROTEUS3, FREDYN, SEAMAN and SIMCAP for specialist simulations of MV Estonia, but will constitute a substantial body of information to be used in the future by the specialists in science of ship dynamics, for purposes of modelling and development of faster and more accurate prediction tools to be used in design practices. More importantly, modelling of complex physical phenomena and successful demonstration of loss scenarios brings about real understanding which can only foster real improvements in design and operation for safer ships. Having built numerical models of MV Estonia, supplemented by specialist experiments pertinent to the circumstances of the loss, an extensive simulation campaign will be executed to corroborate the hypotheses put forward and thus to provide the basis for ranking of the loss scenarios in terms of perceived likelihood of them being representative of the actual loss. The simulations concerning ship dynamics will be performed primarily by the SSRC using the PROTEUS3 code with independent cross checks done by MARIN with the FREDYN code for demonstrating credibility and building confidence in the numerical results. The evacuation process will be simulated also by SSRC using the aforementioned EVI code. Explicit link between effects of flooding on the process of evacuation will be modelled. The results will be analysed, and the concluding synthesis will be reported in consultation with the Industrial and Expert Panel (IEP). It is anticipated that a degree of iteration of the process will take place. The scenario deemed as the most
likely will finally be verified by model tests, to demonstrate the
established mechanics physically. Two tests are anticipated, namely the
manoeuvres in specific conditions up to the instant of the vessel coming to a
stop, and then the foundering process, taking the initial conditions from the
simulated scenario, and also involving testing of flooding through the upper
spaces. High resolution video as well as digital data records will be derived
as the deliverable. In addition,
animations based on computer simulations using a virtual reality model of The knowledge acquired during this process will be synthesised to derive clear recommendations on the measures to improve safety, not yet considered. In particular emphasis will be placed on recommending advanced techniques to be used in design practice, with guidelines on how such techniques can be of assistance. Possible new concepts to be designed into ships for better survivability will be indicated. A report on the advantages of decision support systems and calamity-training simulators will be included. The final report will summarise and detail the
approach, methodology, tools and results of the investigation according to
the process described above, with recommendations for safety improvements and
a virtual demonstrator as a means to enhancing the presentation of the key
findings. The consortium presents a unique and documented expertise, experience and experimental as well as computational capabilities in marine hydrodynamics, ship stability and forensic analysis pertinent to the study.
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