Ing. C. Gallin - Theory and Practice in Ship Design

THEORY AND PRACTICE IN SHIP DESIGN GALLIN

THEORY AND PRACTICE IN SHIP DESIGN

Prof. Dr. Ing. C. Gallin Delft University of Technology The NetherlandsProfessor for Ship Department of ShipbuildingDesign and Shipping

Contents

1. Introduction and Definitions

2. Ship Design Techniques

2.1. Economical Evaluations

2.2. Computer Aided Ship Design

2.3. Optimization Studies

3. Ship Design Objects and Ingredients

3.1. Advanced Ship Types

3.2. Inventiveness

3.3. Strategy

4. Conclusions

5. References

1. Introduction and Definitions

Mr. Chairman, Ladies and Gentlemen,

From my colleague, friend and one of the pillars of this symposium, Prof. Stian Erichsen, I understood that the present paper belongs to the group headed “The Nature of Design”. This suggests to me that I have to behave here, if I can, more as a philosopher than an engineer, or better both of them. My paper should have an overviewing and critical character. I am delighted with this approach. We are used as designers, before starting a project, to make a survey of the situation. Design experience taught us that before coming emerged in a work it is recommendable at first to keep some distance from it in order to gain some perspective, to be able to relativate the input data, factors and constraints, working methods and desired output. By this I do not mean people to do so much thinking that

International Symposium on Advances in Marine TechnologyNorwegian Institute of Technology, June 1979, p. 43-67


they do not start at all or become afraid to even do so. Designing is a mixture between thinking and acting and our time is always limited.

I graduated in 1950 and have remained for 29 years continuously involved in ship design. Being 50 years old, I theoretically have 15 more years before retiring. Two-third of my professional life is passé. This brings one to some changes in his views and approaching methods. The enthusiasm of youth gives way to a more critical attitude. Unfortunately the dynamic makes way for a more regular slower rate. Professional ambitions transform into a somewhat missionary feeling, trying to find and to spread the truth. When doing so, doubts and hesitations occur, which, by the way, is a healthy scientific attitude.

Looking at the title of this paper, “Theory and practice in ship design”, one may sense uncertainty in it. It is indeed so. Hypothetically, theory and practice should go, as always so nicely said, hand in hand. But this is never entirely the case. Ship design develops these days more and more from an art to a science, but in any case an applied science, applied in a very irregular and unstable market, the market of shipping. There is a big difference between for example theoretical mechanics and ship design. I would like to remark hereto that ship design is fortunately not as systematic as some people would like to have it. Prof. Rawson once said in Amsterdam [1], that too much system and order would kill the creativity. I fully agree with his statement. On the other hand, I do not intend to spoil sport to those trying to introduce more system in ship design. I only wish to underline, that correct recognition of the relative importance of things, flexibility and spontaneity are essential in ship design. The danger is namely often, that people, especially scientists devote themselves to systematic abstract topics, things they like to do, which are not implicit the most important or necessary. It is preferable to deal with clean intellectual work than with half logical, half empirical calculation methods. I do by no means wish to thread on other’s toes, but there has been more work done on the theory of propeller design than on steel weight calculations. I am speaking here to professional people, so I hope not to be misunderstood.

Ship design is an exciting and fascinating activity, an art between the modern techniques [2]. The fascinating character of the ship design lies in my opinion in the creative nature and the complexity of this activity. You create a product, the ship or, to be modern, a maritime vehicle, which works as a well defined unit and from which under various physical, social and economical laws and constraints, certain performances are expected. These performances may be deadweight, speed, cargo hold capacity lifting capacity or many other things. The performances of one’s own design may be directly compared under equal circumstances with other existing ships or designs requiring equal expenses. In the struggle with the competition or even between one’s alternatives you have a “challenger and defender” spirit, common to sporting matches. Why should a horse race be more attractive, only because of betting or the nice ladies hats? In a ship design you can, just like in a chess game, influence the final outcome, whereas in horse racing, as a spectator at least, not.

Well, what was said here to make ship design attractive can also be said for other industrial product, such as pens, clothes, furniture, houses and so on. This is true, but like other sophisticated vehicles, such as cars and planes, a ship is a complicated assembly in which many techniques, i.e. steel-construction, engineering, electronics, cargo handling, living comfort, and so on are concentrated within a limited space. The requirements or the



performances of the components are most contradictory, seldom is one design do you have factors working in the same beneficial direction. So the design of a ship or maritime construction is by nature a compromise, as my predecessor in Delft, Prof. H. E. Jaeger, used to say “a big compromise”. And here starts the mixture between sciences and art. A designer should, like a scientist, use every possible knowledge and be really up-to-date with the stand of the technique to avoid wrong decisions and to produce modern, even advanced, designs. But like in a chess game, where because of the succession of alternative and immensity of decisions possible, the follow-up can hardly be programmed in advance, in the ship design too, due to the numerous and diversity of operation requirements, free and depending variables, equality and inequality constraints, remains enough space free for the experience, intuition and genius of the designer. Therefore and fortunately, despite of the trend to technical perfection, design of ships and maritime constructions remains a fascinating activity. My profession, be it good or bad, is still my hobby.

2. Ship Design Techniques

When designing we can distinguish two aspects: the design method and the design object. We need to differentiate firstly because the problem can so be treated easier and secondly because new objects, in my opinion, impose new design techniques, a dependency does exists. From continuous observations of shipbuilding events, I am inclined to state that up to now more practical progress was achieved through the design of new ship types and maritime vehicles or their equipment, than by using advanced design techniques! To be sincere again an obsession of this lecture – in shipyard experience it is now unusual that an order is accepted for which at that time being the techniques for design and fabrication are nor yet clearly defined. Could this unorthodox procedure be caused the former traditional handicraft character of shipbuilding? Or is it because shipping respectively shipbuilding has always been a risky enterprise with large interest involved, nor to be left over to the competition? Or is this otherwise due to the fact that shipbuilding, in larger definition the marine technology, is assembly work, in which the shipyard can rely on partial design work from suppliers and so allow themselves to have black spots at an early stage in their own designs? Whatever the case, I can not imagine a present shipyard manager refusing an order because the design techniques are not yet all available.

2.1. Economical Evaluations

Ships, at least merchant ships, are being built today to satisfy economical needs of countries or interest groups. But also other ship types, whose services are not directly devoted to an economical purpose, such as naval ships, cost money to build and operate and therefore have to be economical.

An economical evaluation is therefore indispensable in modern ship design. In former times it was to conquer the sea, presently the techniques are so advanced, that the sea challenge, although still dangerous, has become of secondary importance.

But what is an economical ship and how does one recognize it? Here things start to diverge.



The definition “economical” is not the same for all partners in building and operating a ship. You must agree with me that shipyards are primarily interested in building the cheapest possible ship, just satisfying the shipowner’s requirements. Shipyards are rather brutal in their attitude, but they are entitled to be so. Under hard competition they try to sell their products, especially nowadays, in order to survive! I have spent twenty years with shipyards and know it very well. “Economical” for a shipyard means “least cost ship” and nothing more. The ship owner in his turn has to buy and operate a ship under given conditions. To minimize the combination of building and operating costs, respectively to maximize the profit, is his main objective. The given conditions are dependent on trade, route country of registration and shipowner himself. The balance between building and operation costs, but also between income and costs as a whole, changes from case to case and with time. Designers know very well that the least building costs ship is not the cheapest one to operate and the contrary is valid too. Therefore we have to do with different economical ship design; according to various circumstances. I use to say to my students: tell me for whom and I shall show you what the appropriate design looks like! So, continuing our logic, to design economical ships for a shipowner, you have to know, as a designer, his circumstances. Risking to be cynical, but remaining sincere, I should dare to say, that in many cases the shipowner himself does not know enough about the operating conditions. He is not always to blame. That would be too simple. The building time of the ship normally takes between one half and two years. It’s operational life, depending on tax laws of the respective country, is between 15 and 25 years. If the shipowner does not sign a long-time-charter when ordering the ship – and not many are that lucky – he takes a great risk upon his company. Nobody can safely predict the future. Also the most clever shipowner can not foresee a long time in advance if a channel will be closed, oil prices suddenly increase or harvest fails, in various places of the world, for any kind of reasons.

Another difficulty in collecting data on economics from shipping companies are the difficult ways in which they compile their statistical data. It is as the building costs calculation at a shipyard, each has his method based on local tradition, specific work organization, etc. An example is the shipowner’s data about costs for maintenance and repairs. What is one and what is the other, where lies the limitation between them? Even with a well organized shipping company this is a problem, but what about collecting data from several companies? And which is the right scrap value of a particular ship to be included in the economical calculations? We meet in our daily work these problems and we are obliged to make all sorts of intellectual acrobatics [3].

Now continuing to the be open and sarcastic. If shipowners by favorable circumstances, regular service conditions, long experience and well organized administration -–by the way not generally the case – are in a position to furnish correct and complete data for the design of an economical ship, they will not always do so. This is not so negative as it may seem. Let us suppose a shipping company has built up in time, through continuous efforts and eventually at the cost of “learning money” a relatively good going service. Or they discovered by intuition or chance a hole in the market. Or know-how for a certain trade or service, for example offshore, has been carefully built up. Why should it be spread out via shipyards to the competition? We know by experience how easily a ship designer in a shipyard can obtain – via suppliers – information about what



equipment the competition has provided in their design. How proud is a shipyard to tell the shipowner X that also shipowner Y has paid attention to or is just studying the design in question! Drawings are usually circulating not only let us say vertically between shipyard to shipowner, but also horizontally between shipyards on one level and between shipowners, banks, shipbrokers on another.

Without being disobedient to our chairman, Prof. Benford, I would still like to make the remark that no perfect economic criterion and no uniformity does exist for comparing alternative designs. The criterion used depends or course, if revenues are known or not, if the cash flow is variable or constant, if the ships have equal or unequal transport capacity or operational life. But let us say in one case, i.e. for known revenues, some prefer the criterion Net Present Value (NPV), others Internal Rate or Return (IRR) for different reasons. Unfortunately the resulting optimum ship design depends also on the criterion used [4].

In Delft students graduating in ship design are strongly encouraged to elaborate their graduation thesis in cooperation with a shipbuilding or shipping company or institution from inland or abroad. In this way actual tasks, realistic working methods and, last but not least, input data especially for economics can be better obtained. We often realize how difficult it is to obtain general data from shipowners, in particular economical and especially data concerning revenues. Even with the best friendly relationship and open books on the financial part, the fiscal chapter, the taxation, remained top-secret, the field of another specialist, the tax consultant.

In conclusion: by nature of things the tasks are divided and probably will remain so. From an enquete on the employment of graduates in naval architecture at the Delft University of Technology until 1973 resulted that only 6,5% of them were employed by shipping companies. Thus the number of engineers disposing of operation data of ships, if available, is also small.

We may perhaps add those engineers working as consulting naval architects (9,7%), who, when consulted, may sometimes be supplied by shipowners with business data, the total percentage still remains small (16.2%). By way of comparison, shipyards alone employed at that time 27,8% of the graduates.

A large spreading of economics in ship design, from the point of view of shipowners, remains therefore a dream. However, building costs calculation cannot be left out by anyone, neither by shipyards, as we have seen, nor by shipowners, investment together with the costs of capital play an important role in their decisions.

Does this mean that we shall close the books on ship design economics and better go and do something else? Of course not! It was only to demonstrate our limitation as engineers.

The designer must be aware of what the customer really wants, so as to best meet his needs. He must have enough knowledge of shipping economics to understand his partner, and most important to speak “his language” at negotiations. It strikes me how few naval architects are in the board of shipping or shipbuilding companies, probably due to their ignorance of economics. This situation should change!



2.2. Computer Aided Ship Design

A phenomenon of our time is the revolution of computer aided ship design (CASD). About 15 years ago the computer penetrated into the design offices and is today definitely established. Ship design is not any more conceivable without computer. The formidable, in the meantime fully recognized advantages of the computer, tempted some of us, in the second half of the sixties, in our enthusiasm, to try to automate de design procedure [5 to 10]. The computers, with their tremendous calculation speed and storage capacity, are ideal instruments, especially when similar design alternatives are to be carried out and evaluated by time consuming operation research and economical evaluations. It is an indispensable instrument for optimization studies.

Strange enough the computer did not succeed in automating the design procedure, at least as far as the preliminary design stage is concerned. So far as my knowledge extends, sophisticated integrated programs in batch mode for preliminary ship design are more a privilege of universities and research institutes, than of design offices of shipyards. Nor are there any specialized firms known to me – and here I have to be careful – that by offering such programs have booked large commercial success in doing so. The contrary is true in the case of programs for certain calculations, such as hull lines, hydrostatics, resistance and propulsion, weights and centre of gravity, strength, vibration and so on. Nobody will do these calculations today by hand if programs are available; this still means a considerable progress. The computer has of course also penetrated into the design process itself, but has not excluded the designer, it helps him more and more to make the right decisions. We have so to speak to do with open, conversational and interactive design models, in which the designer can interface in the computing progress [11 to 15]. Why this different approach? The answer lies in the complexity of the ship design as well as in the instability of the shipping market. To conceive, formulate, write and test a design program for a modern ship, sufficiently sensible for optimization, taking into account all parameters and constraints involved, can according to the circumstances require one or two years of work. A time and money consuming enterprise. In the meantime the market requirements may change, thus rendering the design obsolete; oddly enough that there are those who think that shipbuilding is a grown old profession! Ship types alter, improve continuously and new types appear. Who would have thought some years ago of the success of ro-ro ships with stern, quarter or slewing ramps, or the variety of maritime constructions for the offshore industry? Problems change, variables and constraints too. Concluding, computer aided design models have, in any case, to be flexible, adaptable and preferably simple.

However, the effect the computer has on our design thinking and working procedures is a considerable one. As with nearly everything in this life, we may speak here also about positive and negative aspects.

To start with the positive ones: as positive we can mention that the computer brought more order into design thinking. The flow diagrams of the computer processes were taken over to illustrate the design model and thus obliging us to better thinking from the beginning about what we are going to do. The “yes or no” working style of the computer helps the logic of designing. Furthermore the numerical world of the computer, the unavoidable algorithms, stimulated a more methodical ship design.



Another major benefit in the design process by using computers is the decreasing importance of approximating formulae. When in possession of sufficient subroutines a designer can comfortably use them repeatedly to find an appropriate value of a parameter instead of reflecting on which formula to choose or pondering over its coefficients. For example, instead of hesitating which line (of Ayre, Alexander, NSMB and so on) to choose in the formula for the block coefficient, we can easily let the computer calculate the required propulsion power for given speed, for several block coefficients and determine ourselves, according also to other design aims such as cargo hold, container capacity, etc., which coefficient value is the best. This is a more realistic approach. The same is valid for weight calculations in place of global specific weight values; there are, in short, many other examples that could be mentioned.

Another, not detrimental nonchalance, made possible by the computer, lies in the sequence of the design steps. Formerly, an experienced designer carefully reflected about the succession in his design work to come with the least of detours, and in the shortest time, to an acceptable design. A frames sketch, for example, was at the beginning sufficient to start the design, the hull lines drawing, as a time consuming delicate work, was done only when the iteration process became ripe. Today drawing the lines by computer, my students “order” the lines in a very early stage and do not care if 3-4 lines are to be drawn in a normal preliminary design. It looks like a waste, but it has advantages too. Even though it may change, an early impression of, in our case the deck contours and the available space in the ship, is beneficial. The same is true for the results of other premature partial calculations, which give an idea of the order or magnitude of propulsion power, weight, trim, stability and such like.

But one of the most obvious advantages of computer aided ship design is in my opinion an increase in the reliability of formulae and calculation methods by extending the analysis of comparison ships, prior to our own design work. Most of the ship design calculations include, hidden or not, pragmatic coefficients, an unavoidable mishap. Therefore the best way to check the reliability of a certain calculation technique to be used in a given design remains to apply it first on a similar existing ship, determining the ratio between theoretical and practical results, what I call “experience coefficient’. Because the amount of computer work is not so important, experience coefficients may be obtained for nearly every partial and total result, for which similar ships and computer programs are available. The designer experience extends by computer aid more than his professional lifetime alone would ever have allowed.

And now the negative aspects of the computer aided ship design. Besides need of computer facilities – more or less standard equipment today – and the programming work – impediment already discussed – the computer aid diminishes considerably the insight into the respective calculation method. It is true that those preparing and writing the program must discern at least once the calculation method to be programmed, a fact indispensable for a good job. This should also be the case with the designer using that program. Only what I observed with students and valid for everybody, is that comfort makes lazy! Output of a subroutine once obtained is immediately used further in the design process, without reflection on its occurrence. If there are doubts in the results, the input data is checked again, but the calculation method is taken for granted. Why not, the program has once be approved! That the chosen calculation method



perhaps by her nature is not suitable for the particular case or that the built-in constants and constraints (so many in the ship design) do not correspond anymore for the given case, does not catch the eye at once. In the former manual calculation techniques, the between-values in the course of a calculation were for an exercised eye an alarm signal. This possibility becomes somehow lost. “Out of sight out the mind” is the right expression for this phenomenon. I wonder if the computer, in educating engineers is not even harmful. Harmful or not, I do not speak against CASD. Summing up it can be said that the advantages of the computer in the modern ship design are overwhelming. No ship design is conceivable anymore today without the computer, even if only a small desk computer, or to use modern terms chips, are used.

2.3. Optimization Studies

Another ideal and drama in modern ship design is the question of optimization. Theoretically each accomplished ship design should be the optimum for the given owner’s requirements and existing constraints. The definition of “design” and “optimization” are synonymous. In practice this is never the case. Formerly, in – so to speak – manual ship design, by slide rule or primitive adding machines, the time and means for a perfect optimization, including economics, were never available in a design office. At the most some alternatives were set up and the best one was carried out.

Also in the optimization field the computer created great possibilities. Here too, nice enthusiast work has been done in the last decade [16 to 20]. Nevertheless, we must admit that optimization studies did not achieve a large scale of use. The reasons fir this are partially already mentioned in the chapter reflecting on economics in ship design. Furthermore, the time between inquiry and tender is almost always short; in any case too short for an extensive optimization. Until the contract is assured the shipyard will not usually invest too much in a sophisticated optimization work. If the financial aspects are settled, the shipowner wants to obtain his ship as soon as possible. If the contract is signed, the workshops of the shipyard are asking for drawings and the planning office of the shipyard urges for the final design.

Bearing this in mind, real optimization work, if any at all, is in practice carried out only in the context of studies for a new ship type, for example a standard ship, after an active marketing campaign by big shipbuilding companies; universities and research institutions have, for the moment, been left out of these considerations. It could be argued that the computer could help here a lot. IT does indeed, but only on a limited scale. Firstly, we should not forget that the high level of knowledge in mathematics and economics, combined with experience in ship design and computer techniques, needed in optimization studies, is not often available at small or average size shipyards. Furthermore, for a computer aided optimization process, working more or less automatically as envisaged at the beginning of this development, you need a design model in batch mode, with all disadvantages of the last one already discussed in the previous chapter.

Let us forget for a while the already shown lack of communication between shipowners and shipyards. In the matter of economical operation data, that are indispensable in optimization studies. Let us assume this information line does work. The optimizer will be overflowed with input data



while trying to consider all the factors of influence from the shipping market plus those of the ship design, both of which we already know as being complex. Numerous free and depending variables are, as I said before, the consequence. Unfortunately the degree of complication of optimization methods increases steadily with number of variables. Five or six are enough for such an optimization technique, but not for a ship design. Of course you can optimize a design only as a function of one or two variables, but is the result then a practical optimum? What after all is a practical optimum in the design of a ship? An optimization technique by computers leads, after a search procedure with penalties for constraints and according to the built-in accuracy, to one point, “the optimum”. Such a point may exist, but in doing so, have amore theoretical than practical significance. To my experience with design alternatives, parametric studies and optimization work, the curves of object value, i.e. of an economical criterion as function of design parameters, are most pretty flat, neighbouring points of the optimum on the curve of the object value being therefore – from a practical point of view – just as acceptable. As a matter of fact these side points may eventually be even more attractive. In a ship such as a bulkcarrier, for example, the weight of the engine plant does not play the most important role and the shipowner will gladly accept a heavier plant of a make for which he has uniform spare parts or from a manufacturer with whom he has good business connections or in whom he has confidence. All these factors are difficult to introduce in an optimization study and this is only one of the many possible examples.

Speaking in terms of practical designing, parameter studies, in which the parameters are systematically varied in tabular or matrix form and the results displayed either manually or by computer in the form of simple graphs do a very satisfying job.

The ship design does not require an accurate quantitative work, like in a pharmacy. Neither can the task of a ship be calculated and optimized as the route of a satellite working under the unchangeable laws of the celestial mechanics. Therefore the field of the optimization studies in ship design remains exclusive for only very special well defined cases, for research purposes and teaching techniques, an attribute typical to research institutions and universities.

3. Ship Design Objects and Ingredients

Following the general trend and conforming to the title of this symposium “Advances in Marine Technology”, if we speak about ship design objects we have to concentrate on advanced ship types and forget for a while the evergreens. Indeed, design means per definition – as we have seen – creativity and progress. These beautiful attributes should be theoretically expected in advanced ship types.

3.1. Advanced Ship Types

One can scarcely read today all the information on new buildings, to follow exactly the development of new ship types. In the last two decades we have seen some very distinct appearances, such as container ships, barge carriers, roll-n/roll-off ships, gas tankers, etc. Only these new ship types did not appear t once, but gradually penetrated the market. For example, the container came from land, from furniture manufacturers, to link the sea with the land, the road and the rail with the ship. Practically all



everyday cargo ships are designed now for carrying containers too; container ships can take refrigerated containers in increasing numbers, container are stowed also in ro-ro ships using special loading equipment. It is the same in the offshore field, where semi-submersibles are spreading out, serving for various services: besides exploration for production, pipe layers and floating cranes, or as hotels.

But what does an advanced ship type really means?

The fast liner cargo ship of 21 to 24 knots, as pure dry cargo ship, once considered as an “advanced type” have almost disappeared, his place being taken by fast container ships. The reason is obvious: the investment in building and operating at high speeds is not anymore compatible with present oil prices and with labour costs for conventional loading and discharging in harbour.

The multi-purpose cargo ship, best suited for standardization during the last ten years enjoyed great popularity, first as “Liberty replacements” and afterwards as a well established ship type. Here we detect an important advanced design concept, namely to simplify ship types, to design them production friendly and so, meeting rationalization efforts, thus suppressing radically the building costs.

In the process of helping the less developed countries or through their own progress, they consequently took over an appreciable percentage of the world’s shipbuilding. There are no reasons why this trend should change. The only chance for industrialized countries with high labour costs to maintain or not to lose their output in shipbuilding is to rationalize the production. An alternative is the other extreme, to build sophisticated ships for which a specialized knowledge and building experience is required.

The container ship has ripened in design, the storage of containers below and on deck, is well solved. Container ships up to 3000 TEU or developing up to 120.000 HP and running over 30 knots have been built. Gas turbines have been adopted for the propulsion of sophisticated container ships [21]. Only we read now in the professional press that the gas turbines in that case will be replaced by diesel motors and the speed will be reduced from 26 to 21 knots [22]. What does advanced ship types then mean here?

Worth observing is another example of advanced ship design: the barge carrier. A very logical and promising concept for combined sea and inland water transport., using big floating containers, the barges, which moreover help against congestion in busy harbours. The high investment versus the low quality cargo transported, respectively income, problems of maintenance and surveillance of the barges in harbour as well as the necessary but not sufficient international coordination restricted somehow the expansion of this interesting ship type, at least not so far as container ships did. Studies made in this direction some time ago showed red figures [23]. Some of the existing barge carriers were converted back into container ships. But still new proposals continue to appear [24], new barge carriers of various designs are being built [25].

The moral of the story is that “advanced” ship design is not always evident or mean the same by time.

The story of barge carriers includes unfortunately one more tragic event, the loss of the “München”, the Lash-Barge Carrier, 260 m in length, 43.000 tdw carrying capacity, on 12th December 1978. Nobody doubts on the reliability of the design and construction of that ship. But are we designers



perhaps not too confident on our technical resources, underestimating the complexity of the sea challenge when introducing on a large scale new design concepts? 16m high gantry crane and barges of 450t each on two layers on deck are remarkable design requirements [26].

Many specialized designs have already been created for LPG/LNG carriers and more will probable still come. Anyway, advanced design techniques would still be necessary if the “normal” size of today of 125.000m3 should be increased to 330.000m3, as proposed in [27].

Well, the oil tankers cover more than one half of the world fleet. Their individual size attained as much as 554.000 tdw and caused in the sixties many problems, due to draft restrictions [28] or due to required strength. They were the advanced designs. Apart from this. From a design point of view the oil tankers are not as exciting as other ship types. However, through their regular service, one way payload and return and ballast, running mostly under longtime charter and strong competition, oil tankers are well suited to optimization studies. The oil crisis of 1973 and the transport over capacity which followed, practically stopped the new building of such ships. But for one exception we can speak here on advanced ship designs of oil tankers : the new IMCO regulations against oil pollution at sea, the Marpol 1973, the SOLAS 1974, both amended in February 1978 [29]. The segregated ballast tanks and corresponding design requirements, as consequences of the last pollution catastrophes certainly give work for advanced design to naval architects. In designing product or chemical tankers the IMCO regulations too, the so called “codes”, are a field stimulating advanced design thinking.

About bulkcarriers we may say the same as for the big oil tankers, referring to design, to size, competition, etc. Only an optimization process is much more difficult, because of the irregular services. But, like ordinary multi-purpose cargo ships with obligatory low building costs, the bulkcarriers are qualified for standardization. Standard ships may sometimes be regarded as both dry cargo ships and bulkcarriers. Advanced design techniques to rationalize the production and operation of standard ships are applicable for bulkcarriers too.

Train and car ferries, mostly both combined, including their passengers, are well known ship types and not new. With increasing number of private cars, rising standard of living and holiday-makers, the demand for this type continuously increased, even in period of depression in shipbuilding. Passenger ferries together with the cruising ships are the only successors of the once so famous passenger liner. The business of the last category is taken over by jumbo airplanes and the prestige by supersonic “Concorde”. Advanced ship design for passenger ferries, because of the short routes and to make them remunerative, means sometimes unfortunately a maximum number of persons and vehicles like sardines in a can.

On this point I would like to praise the courage and the technical achievement of the Finnish shipping and shipbuilding industry. They built two years ago not only world’s largest (1500 passengers), but also the world’s fastest passenger/car ferry (30,5 kn), the gasturbined (2 x 37500 PS) “Finnjet” [30]. The comfortable ship proved to be a success. It saves 22 hours on the route Helsinki-Travemunde and so grants to the holiday-makers one extra day each way.

A significant role is enjoyed today by a derivate of ferries: the roll-on/roll-off cargo ship, in short ro-ro. They are built, as we all know, according to



the same principles as ferries, only the vehicles are vans, lorries or trailers, loaded with cargo. The passengers – with the exception of up to 12 drivers – have disappeared. For this reason their best name may be of “ro-ro cargo ships”. Their expansion is due to the simplicity of cargo handling. The quick loading and discharging procedure counterbalances economically the losses in cargo hold, caused by and between vehicles. Of course the balance depends on the ratio length of the route to number of harbour calls, and the preference for road against rail by many transport companies seems to shift the break point in favour of the ro-ro. The cargo handling equipment on wheels, driving on board over ramps, eliminates pretentious harbour facilities [31]. The discovery of quarter or even more slewing ramps reduces the required harbour facilities to a simple quay and a place to park and manoeuvre the vehicles; for undeveloped countries and agglomerated harbours a very strong argument. The conclusion of this observation could be that under advanced ship design we should by no means always understand complicated design, just the opposite may be the case.

As always in design work, by introducing a new system you cannot only book benefits. The simple cargo handling system of ro-ro ships using ramps implicates special hull and poop forms, big openings at the stern along with weights of ramps of up to 400 tons, which must be permanently carried. Here indeed is room for advanced design techniques, i.e. strength calculation, to find the best construction, to minimize and accurately determine the necessary additional steel weight [32]. Operational research studies should determine optimum sizes of ramps, position of sorting areas, traffic on board, etc. In addition to this being floating garages, effective, less cost systems for ventilation and fire fighting, corresponding to modern rules and regulations, are to be optimized. Finally, watertight subdivision with longitudinal instead of transversal bulkheads, according to IMCO resolution A265, favours loading of vehicles on lower decks. An increase in the number of drivers without all the requirements for passenger ships may be a promising feature [33].

Most of the arguments applied to ferries and ro-ro ships are also valid for the specialized ships used in the car export. Interesting equipment design – movable car decks – have also been produced for the same purpose, to obtain cargo flexibility or to use bulkcarriers as export car transporter. N advanced design can mean equipment for multi-purpose use, i.e. for less voyages in ballast.

The above examples illustrated advanced ship types for transport of goods and people. We shall now consider the second large group of ships for special duties.

The stern trawlers made their way and practically liquidated the side trawler. Increased size of trawlers, at the same time factory ships became modern features. Advanced ship design means for fishing boats advanced fishing techniques, electronics, etc., in order to give the fish no chance to escape! The extension of national waters to 200 miles zone brings to many countries – especially to the undeveloped ones – the need to explore the fish reserves of their waters. Therefore, research vessels are needed.

Fishing by own means on a large scale is an important matter as a source of food and labour, especially for less industrialized but densely populated countries. Advanced ship design means here the most suitable ship, to be



built with little money under primitive building conditions. Multi-purpose simplified standard fishing boats could be the right answer.

Advanced ship design with seagoing tugs today means high values of bollard pull, respectively installed horse power, as well as their capability to serve also to the offshore industry. Ships developing 300 tons bollard pull and having 26.000 HP are already built. The explanation here is the need to handle and eventually rescue modern ships of increased size and displacement, especially mammoth tankers or huge offshore constructions. The exploration of oil and gas fields north of the polar circle and the technical progress permitting installation of large propulsion power in a relatively small space led to more and more powerful icebreakers. Gasturbined icebreakers with 150.000 HP propulsion power are presently in design stage. Besides icebreaking tankers and bulkcarriers are a reality [34].

Pusher boats and cargo barges form a classical system for inland navigation; not equally so in the case of the seagoing ones. Many efforts have been done to solve the problem of the connection between the pusher and the ocean going barges. Various proposals appeared and some of them have been realized. Can we speak here of advanced design? Perhaps technically, but economically operational there are still some doubts too [35].

With increased traffic and ship sizes, with development of new regions, dredging will remain actual and in demand, but the competition between the builders increases too. Advanced designs in hopper dredging, such as the split trail or active rotary heads and in cutter dredging self elevating walking platforms are realized. In dredging advanced design may be synonymous with reliability in operation under heavy working, soil and sea conditions, maintenance and repairs, often in far away, isolated places, where assistance is not easily available. Also the semi-submersible principle may penetrate in this field [36].

The last but not the least category of ships and maritime constructions to be reviewed – a relative new and well defined group on its own – is the group of vehicles serving the offshore industry. The group has been so important in the last years, that the work-hungry shipyards have also created and overcapacity there.

Ships and maritime constructions for offshore, so far steel constructions, are mostly built at shipyards. This fact has a logical explanation. The shipbuilder knows the sea. The ship designer is accustomed to all the constraints, like stability, resistance, seakeeping, corrosion effected by the environment. He can solve strength problems and the workshops are able to manufacture and handle heavy steel constructions. Offshore vehicles are assembly work as well, of which marine engineering forms a good part. A new aspect here is the required knowledge and skill of oil production industry and in the future, sea mining. In advanced designs the shipbuilders must create optimal working conditions for the last two named industries.

The development followed indeed this direction. Ships were converted or newly designed for drilling activities. A maritime vehicle with less possible movements in sea way, i.e. minimum ratio waterplane to displacement, the semi-submersible, has been built on a large scale. Starting with drilling activities for oil exploration, it now extends to production too [37]. Pipe laying equipment and heavy cranes, at the beginning installed on converted ships, are now being placed on semi-submersible of impressive



sizes and displacement values to reduce the inactive days to a minimum. Support ships for maintenance and accommodation of crews are for the same reason also semi-submersibles. Various designs of platforms on three, four, five or more legs, rectangular or circular in form have been built. The underwater bodies are for different reasons spheres, cylinders or pontoons. What advanced means here, is not so easy to answer. Advanced may be here besides seaworthiness, i.e. minimum down time, increased deadweight (a weak point of such vehicles), better propulsion but also simplified form and rational production.

We cannot close the chapter offshore without mentioning once more the fleets of supply vessels, already existing in various sizes and for different services, such as towing, anchor handling, fire fighting, salvage, icebreaking and not to forget supplying the drilling rigs with pipes, cement, mud, etc. In their design they resemble tugs; the main difference between supply vessels and tugs is the required higher deadweight values and the space on the after deck for cargo storage. Advanced design can be here versatility, multi-purpose again [38], remembering that a pocket-knife with many functions, such as to open bottles, cans, etc., is not really satisfactory for any.

Lastly, a word about submarines and unmanned seabottom working equipment, which in the future may aid on large scale recovery of minerals from great depths.

Offshore is a typical field of shipbuilding and marine engineering open for inventiveness. I do not need to speak about that here in Norway. However, inventiveness is an attribute of advanced ship design, the spices in a meal.

3.2. Inventiveness in Ship Design

Inventiveness in ship design is a fascinating subject. It is a game with many components, requiring born talent, professional knowledge and experience, favourable circumstances, persistence, but also a realistic approach, a feeling for economics, a sales strategy and, last but not least, seriousness. It is a topic which more or less followed me and perhaps many of you during our professional life.

I had the pleasure to read a paper entitled “Inventiveness in Ship Design” before the North East Coast Institution of Engineers and Shipbuilders, in Newcastle upon Tyne in October 1977 [39]. There I tried to define what ship design and invention each are, what is common and what is different with them. There is an interlace between inventiveness and advanced ship design. Inventiveness and designs joined together on a very thin border, especially in advanced ship design. The “hot” aspect of the comparison between design and inventiveness was the question: “can a designer afford to be an inventor and if so, how far? Shall I infect my students with the virus of inventiveness, which in extreme cases could lead to incurable illness and disaster, or shall I recommend them to design, with small improvements, only that which has existed before, to avoid any risk at the same time suppressing fantasy and the wish to struggle for competition?” In that paper an attempt has been made to formulate, on behalf of the students, from own experience and from observation of contemporary professional developments, some principles of inventiveness in ship design. In the beginning it appeared nearly impossible to find rules and regulations for good invention. Who has the right to do so? Not everybody is a Moses!



But thinking more about it, one feels that there must, at least, exist some guidelines for it, as for any other activity oriented to reach a target.

Following the line traced by Prof. Frederic Bacon and Prof. Herbert Schneekluth, tentative principles for application on inventiveness in ship design were formulated. These principles are as follows:

An innovation should come out at the right moment.

Not all inventions which have failed should be forgotten, some of them deserve reconsideration periodically.

Most successful inventions do not suddenly appear on the market, they are the result of step by step application of inventiveness in ship design.

Shipowners do not like inventions!

Do not include in a ship design more than one major invention at a time.

An invention to be accepted in a ship design has to be first of all reliable.

To be reliable an invention has to be built up as far as possible of conventional material and parts and has to be easy to maintain and repair, that means it has to be simple.

An invention to be accepted by a shipowner should offer substantial economical profit.

The profit of an invention should be presented in the most attractive manner for the customer.

A designer should not hang on to the whole of an invention, he should accept partial results or whatever comes out.

The shortest of these principles, “shipowners do not like inventions” is perhaps the most significant. The reasons why are given in the named lecture [39]. Lively discussions on that occasion produced two more additional principles. One principle came from Dr. Buxton, on economical side, namely that

“The ship size of the investment has a negative effect on an invention, this related also to the insufficiencies of time and staff, alloted in shipbuilding for design and estimating”.

Another principle, by contribution of Dr. Teasdale, was that:

“It is not sufficient to produce something new in one of the three disciplines design, production and marketing and neglect the other two”.

This is so much the more seeing as “the second chance takes a long time in coming”.

What do such principles mean? If a ship designer follows them, is he successful? I should say not at all. To cite from my paper:

“Our principles are only a sort of bulkwark to prevent us falling into the water, or a radar at night for safe navigation. But if one is a good captain, to make for port is another matter. I am afraid the question mark must remain over whether inventiveness should be applied in ship design. The right answer depends on so many extra factors and imponderables, to be decided as the case may be. But one thing is sure, the path to having an invention recognized and realized is a long, hard one. This warning should



be given to everyone from the beginning! To start with the patent application is no easy matter.” ...

“It makes little sense, if benefits are envisaged, to apply for a patent only in one’s home country, especially in such international and worldwide business as shipbuilding and shipping. The whole procedure is an expensive adventure.” ...

“For individuals, young engineers, the solitary way is mostly impossible. The help and encouragement from the companies employing them depends upon the benefits in view, cost involved in research and prototype building, company policy and not least it depends upon their own position in the company. And this is just the beginning of the story.” ...

“The materialization of an invention, the building of the prototype, is the second big step. Preliminary design, estimates, workshop drawings, model tests, building costs and full scale trials are expensive activities, at least in shipbuilding and marine engineering.” ...

“To convince people and to raise money for an invention is not easy. It is a struggle in which, paradoxically, good results meet extreme enemies in the form of human jealousy and competition. The innovation baby can die shortly after a healthy birth.” ...

“The third phase, the time to get the full commercial value from an invention, is like the estuary and the sea for a river. It is big business fending for itself, depending, as business does, on market, customers views, management, production facilities, sales organization, again, capital and, perhaps, an element of chance. And if times are bad, as so often in shipbuilding, the best innovation does not receive any help! How would an inventive oil tanker designer earn his living today? “...

Summarizing: the gap between theory and practice of the conventional ship design is even more acute when dealing with advanced design respectively inventiveness. I still concluded:

“In spite of the miseries, and independent of financial results, the inventiveness in itself, the enthusiasm proceeding from it, the impulse for research and accomplishment, the emotion of model or full scale testing, the negotiations with the patent offices, progressing work with your own company or with clients and the increase in self confidence are wonderful.”

To young engineers I gave the advice: at least, try.

3.3. Design Strategy

The ultimate sense of a ship design is the building and selling of the design objects. With only a roll of design drawings this can, of course not be achieved. There are the well balanced efforts of the technical and commercial staff of a shipyard, under the right management, necessary to assure that a good design comes at the right moment on the right market, being competently presented, negotiated, realized with minimum costs, and, last but not least, adequately financed. The builders, in most of the cases the designer self, have to fight and win a battle under hard “shooting fire” of the competitors. Thus I feel the word “strategy”, in our case “design strategy”, is to the point. It is nor one quality alone, but a symphony of disciplines involved in and around the design, which leads to practical success. Without pretensions of completeness we shall pass in review some components of this indispensable strategy.



Starting with the question of the right moment and market: as a rule, the work begins in the design office after the telex with the shipowner’s inquiry has arrived. This is a standard, but not advanced working style. Time is in such cases short, not permitting well though out design alternatives, with the aim to find the best one.

A solution to the above problem is already given by many shipyards or big marine companies. By means of marine market analysis, fleet development and new building, requirements are being studied and forecasts attempted [40]. We may think what we like about forecasts and doubts are motivated, but under conscious approach of possibilities and limits of forecasts, they can at least serve as tools for flexible planning. The development trends may be recognized, sensitivity studies on the influence of different factors on the financial results carried out in advance, so that when certain factors come into force, decisions can be taken quickly and justly. Shipyard capacity and tonnage demand can so be better compared. The reliability of market analysis may not be enough to build ships in advance, but it may be for designing them.

Another, from a strategic point of view, positive feature of advanced ship design to cover the deficiencies of forecasts, could be its versatility. The ship can be so built as to serve unchanged for more than one task, the so called “multi-purpose vessel”, a frequent type today, already mentioned. The versatility however, can also be included in the design itself, the construction being based on modular systems, with interchangeable components. For example, for the same hull we may consider the built-in possibility for longer alternatives, different cargo gear equipment, containers versus ro-ro and bulk, or propulsion engines of various outputs. We have similar successful examples from the aircraft and car industries.

Dr. Teasdale in ref. [39] reminds us of the importance of production for advanced ship designs. Indeed advanced designs require for their success advanced production methods and vice-versa. Looking back on history, the introduction of steel as a material changed the design concept of former shipbuilders. More recently, the welded construction, in prefabricated sections, depending on the lifting capacity of yards’ cranes, may determine the subdivision of ship, i.e. the design itself. I would like to call such advanced designs “production friendly”, in which the concept is particularly oriented to an optimal production; this should theoretically be routine and not exceptions.

The presentation of a design is not, in my opinion, a factor of minor importance. BY this I do not only mean the quality of drawing work and paper. These too have to correspond with a certain standard, to be clearly and orderly done. We should not forget that the shipowner himself does use the design in negotiations with charterers, banks, authorities and would like to make in his turn a good impression. Under presentation of a design I mainly think about the presentation of an object, from a customer’s point of view. The designer knows the advantages and disadvantages of his product. At least advantages should be clearly and simply presented, so as to make his customer’s decision easier, the decision makers often being qualified persons from the commercial side and therefore less familiar with technical possibilities. One technical advantage may be “translated” in different ways for the benefit of the owner. In ref. [41] such an example is shown.



The importance of financial support in shipbuilding is obvious and only too well known! How many good designs have not been realized, because the financial side could not be settled, and vice-versa, how many beginners in ship design took over orders, thanks to financial facilities, government subventions, etc. Therefore to design strategy belongs cleverly deviced financial background.

Unfortunately, the financial support does not only extend to a favourable payment conditions. We have already seen that advanced design of advanced ships and maritime constructions may ask for new or adapted production techniques, respectively production equipment, which in some cases went so far as to create new shipyards. And that is not yet everything. In ref. [39] Dr. Teasdale underlines another aspect of shipbuilding market, namely a “threshold” has to be passed, i.e. a sufficient number of a new ship are to be sold, for success to be achieved. Indeed shipowning is a risky enterprise, not so much because of the sometimes somewhat unfriendly physical environment, but more by the unstable shipping market, hanging to worldwide fluctuation. With the large sums of capital engaged, shipowners are entitled to avoid any extra risks and therefore prefer to order a ship from a proven series. For the builders to build a series of ships at “coûte que coûte” conditions, require an appreciable financial effort. In ship design too, money brings no happiness, but are good catalyzers.

4. Conclusions

It was the task of this paper to give evidence concerning the discrepancies existing between theory and practice in modern ship design, between how we should perhaps like designing to be and how it is in reality. The latter being so, not by chance, but by reasons of practice. We may shift of our views on ship design. It was the intention of the author that by relating different aspects of modern ship design, one might find out what is important and what is not in practical design. More significance was paid to the design objects, so called advanced ship types, than to new design techniques, because the first are in practice the promoters, while the second are determined and a consequence of the first ones.

Respect was shown for economics, as the purpose, the “sine qua non” of modern ship design. Just as a naval architect must speak english today, the international language of shipbuilding and shipping, the ship designer must possess a basic knowledge of economics to understand his partners. Unfortunately, no uniformity exists in cost calculations and economic criteria. Even should this be the case, the communication between the parties involved on economic data is bad, due to the divergency of interests.

Reference has been made further to the computer as a great non-dispensable help for the designer, but warnings have not been hidden on negative aspects and limitations of computer aided ship design. Optimization studies have still to be regarded as work of elite, only done in special cases.

The more we think, the more we must conclude that practical advanced ship design does not always mean the same. An advanced design is there to meet new necessities of our society and they can be entirely different. The obsolete Liberty ships of the second world war made way for multi-purpose cheap standard cargo ships. The threat of less developed



countries to become shipbuilders, obliged the industrialized ones to rationalize the production, with all consequences for the ship design. Further, the upper limit for merchant ships’ speed, the economical “sound barrier” for ships, as well as the high labour costs in ports of the developed countries, induced advanced cargo handling, such as containers, barges and ro-ro’s. Agglomerated harbours or primitive facilities of new markets brought the expansion of the ro-ro type vessel. Relatively new industries, such as offshore, created new ships and maritime vehicles. Finally, catastrophes can sometimes promote advanced ships, respectively design rules, as did the “Titanic” for SOLAS and “Torrey Canyon”, “Amoco Cadiz” for MARPOL.

Advanced ship design may mean simple or just for the sake of it advanced; for snobs in ship design sometimes trivial, but not unimportant! The wheel is simple too, but the Aztecs would not have operated ro-ro ships. Under advanced design we may understand not only simple, but also cheap to build and operate. Quick adaptability of design to new cargo and port condition or to new legislation is a sign of advanced design thinking. This does not exclude difficult designs for exigent cargo, such as liquefied gas, heavy goods, etc. this being a consolation for pretentious designers.

Creation of advanced design requires knowledge and inventiveness, the latter theoretically excellent, may in practice be a heavy burden, a difficult way to go with no insurance or reward. Inventiveness can be dangerous for both design and designer. There are some principles which could be followed, however only as guide and not as a recipe.

Finally the best advanced ship design may grow mouldy in a desk drawer, if not strategically sold by competent people at the right moment, and with adequate means on the right place. Just as a successful star, who besides talent needs a good impresario.

I sincerely hope, that my reflections on theory and practice of ship design did not disappoint. But like designs – usually done first on paper instead of building them directly at full scale – it is perhaps better to criticize verbally the discrepancy between theory and practice in ship design, than bear its consequences. For the last time in this lecture, the truth, when recognized, should be said and should not hurt.

5 . References

1. K. J. Rawson, “The art of ship designing”, Europort International Maritime Conference, Amsterdam, 1976.

2. C. Gallin, “Ontwerpen van schepen een kunst in de moderne techniek?”, Inaugural speech (in german) at the Delft University of Technology, Delft, 1970.

3. C. Gallin, J. W. Muntz, G. J. Schepman, J. Punt, “New standard ships or second hand ships? An economical evaluation using computer techniques”, Proceedings I.C.C.A.S., Gothemburg, 1976.

4. Th. M. Oostinjen, “Economic criteria for ship design optimization”, Graduation Work, Delft University of Technology, 1972; Schip en Werf, November 1972.

5. R. D. Murphy, D. J. Sabat, R. J. Taylor, “Least cost ship characteristics by computer techniques”, Chesapeake Section, S.N.A.M.E., 1963; Marine Technology, April 1975.



6. C. Gallin, “Entwurf wirtschaftlicher Schiffe mittels Elektronenrechner” (Summary of Doctor Thesis); Jahrbuch der Schiffbautechnishen Gesellschaft, 1967.

7. A. W. Gilfillan, “Preliminary design by computer”, Transactions I.E.S.S., 1967.

8. L. K. Kupras, “Programming of the elementary design of a shelter-decker 8.000-12.0000 ts.dw”, Bud. Okrer, December 1968, January 1969.

9. K. Puchstein, “Automatisierte Projektierung optimaler Schiffe”, Schiffbauforschung. Sonderheft, 1969.

10. J. Holtrop, “Computer programs for the design and analysis of general cargo ships”, Graduation Work, Delft University of Technology; Report No. 175S, Netherlands Ship Research Centre TNO, Delft, 1971; International Shipbuilding Progress, Vol. 19, February 1972.

11. C. Gallin, “Which way computer aided ship design?”, Proceedings I.C.C.A.S., Tokyo, 1973.

12. E. Deetman, “Ship design on conversational mode, exemplified for tankers”, Graduation Work, Delft University of Technology, 1975 (in cooperation with Verolme United Shipyards).

13. H. Nowacki, “Graphisch interaktive Probleme des Schiffsentwurfes”, S.T.G. Committee for Ship Design, Hamburg, 1975.

14. S. Thorvaldsen, F. Major, “Interactive preliminary ship design with graphical aids”, Proceedings I.C.C.A.S., Tokyo, 1973.

15. C. Gallin, L. K. Kupras, E. Deetman, “The realities of present day ship design”, Proceedings I.C.C.A.S., Tokyo, 1973.

16. P. Mandel, R. Leopold, “Optimization methods applied to ship design”, Transactions S.N.A.M.E., 1966.

17. J. Moe, S. Lund, “Cost and weight minimization of structures with special emphasis on longitudinal strength members of tankers”, Der Ingenieur, Nos. 47 and 49; Transactions R.I.N.A., 1968.

18. H. Nowacki, F. Brusis, P. M. Swift, “Tanker preliminary design – an optimization problem with constraints”, Transactions S.N.A.M.E., 1970.

19. H. Nowacki, “Optimization in pre-contract ship design”, Proceedings I.C.C.A.S., Tokyo, 1973.

20. L. K. Kupras, “Optimization method and parametric study in precontrated ship design”, International Shipbuilding Progress, May 1976.

21. B. B. Carpenter, J. G. Holburn, D. A. A’Neill, “System integration of the G. T. S. Euroliner from conception to operation”, Marine Technology, January 1973.

22. “Diesel statt Gasturbine”, Hansa No. 5, 1979, page 337.

23. A. Peterse, “Optimization of LASH-service”, Graduation Work, Delft University of Technology, 1972.

24. H. Linde, K. Spethmann,, “Ein Barge-Carrier-System maximaler Leistungsfähig-keit und vielseitiger Verwendbarkeit”, Hansa NO. 18, 1976; Hansa No, 12, 1977; Hansa No. 10, 1978.

25. “Lash, Seabee, Baco” “New Lash designs from Lash Systems Inc., developed by J. L. Goldman”;”Julius Fuchik – first of two barge carrying vessels built for Russian ownership by Valmet Oy”;“First Baco-oner, ordered from Thyssen Nordseewerke”;Shipping World and Shipbuilder, January 1979.

26. K. Wendel, “Zum Untergang von München”, Hansa No. 1, 1979.



27. Naval Project Development Company Rotterdam BV, “330.000 m3 Verolme liquefied natural gas carrier”, Rotterdam, 1977.

28. Netherlands Ship Model Basin, “The development of a 425.000 TDW tanker with restricted draught”, Proceedings of Symposium, Wageningen, 1971.

29. W. D. Snider, “IMCO Conference on Tanker Safety and Pollution Prevention”, Marine Technology, Vol. 15, No. 3, July 1978.

30. “Background to Finnjet”, Shipbuilding & Marine Engineering, July/August 1977; “Finnjet”, Shipping World & Shipbuilder, July 1977.

31. I. L. Buxton, R. P. Daggitt, J. King, “Cargo access equipment for merchant ships”, published by E. & F. N. Spon Ltd, London, 1978.

32. J. H. C. Meijers, “Influence or the ramp types on the steel weight of ro-ro cargo ships”, Graduation Work, Delft University of Technology, 1978.

33. M. A. W. M. van Hees, “Design and economical evaluation of ro-ro cargo ships for dangerous goods and 36 passengers”, Graduation Work, Delft University of Technology, 1976.

34. “World’s first icebreaking bulkcarrier”, Schipen Werf, NO. 26, 1978.

35. J. W. Muntz, “Enige beschouwingen betreffende de zeegaande duwvaart”; H. J. Westers, “Zeegaande duwvaart”, Guest lectures at the Delft University of Technology, 1975.

36. L. Goossens, “Semi-submersible dredge”, Graduation Work, Delft University of Technology, 1978;T. P. Jooden, “Semi-submersible dredge”, Offshore Technology Conference, Houston, 1979.

37. B. Bernhard, “Semi-submersible production and storage platform for exploitation of oil sources”, Graduation Work in preparation, Delft University of Technology, 1978/1979.

38. S. Veeman, “A multi-purpose offshore service vessel”, Graduation Work, Delft University of Technology, 1978.

39. C. Gallin, “Inventiveness in ship design”, Transactions of the North East Coast Institution of engineers and Shipbuilders, Vol. 94, Newcastle upon Tyne, 1978; Schip en Werf, No. 2, January 1979 and No. 3, February 1979.

40. B. Nilsson, “Fleet development and newbuilding requirements”, Marine Market Analysis, 3/78, published quarterly by Stal-Laval Turbin AB, Finspong, Sweden.

41. C. Gallin. H. M. Hiersig, M. C. van der Hoek, “The length of the engine room – a challenge to ship design”, Jahrbuch der Schiffbautechnischen Gesellschaft, Band 70, 1976 (in German); Schip en Werf, July 1978 (in English).


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Ing. C. Gallin - Theory and Practice in Ship Design