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In the first edition were two glaring faults, one being the vagueness of the method for determining the thrust deduction factor and the other, the method of applying it in determining the characteristics of the propeller. These have both been eliminated to a great degree by a more thorough study of the effects of hull form and position of the propeller in relation to the hull on the performance of the propeller. The approximate method of computation called ‘the method of reduced diameter’ has been replaced by the more accurate method of ‘variation in load’. The charts of propulsive coefficients and tip speeds have been replaced by the equations derived for the ‘law of varying load’ and the ‘law of varying power and speed’. There is a whole chapter devoted to the subject of cavitation. A chapter dealing with the design of the aeroplane propeller has also been added.

Exploration jack-up drilling units in S E Asia routinely encounter punch-through hazards due to peculiar geological conditions prevalent on the Sunda Shelf. The majority of these phenomena are identified prior to rig emplacement and this hazard is managed with controlled preload measures. However in recent years rigs have encountered unexpected punch-throughs that have resulted in both rig damage and lost drilling time with consequential costs. The S E Asia drilling contractors and operators have well established site assessment procedures in place but jack-up foundation failures continue to occur at an alarming rate. Some of the problems associated with site assessment practice are identified. The paper seeks to promote adoption of more rigorous standards of investigation and analyses in known punch-through territory.

The surface of a diapiric hill in Garden Banks Block 427 (Shell's Auger Prospect Area) is a case where until recently features on that surface defied confident interpretation from both the best high resolution deep-tow data and 3D-seismic surface attribute maps. Direct observation and sampling using a manned submersible in 1992 and again in 1997 provided the necessary data for "calibrating" both the high resolution acoustic data and 3D-seismic derived surface rendering of the "diapiric hill" in Garden Banks Block 427. The linkage between remotely sensed images from the diapiric hill surface and submersible- acquired ground truth observations and samples are discussed.

Seakeeping performance is studied in detail as early in the design process as possible. First principle methods of seakeeping assessment are applied to assess seakeeping qualities of ships in waves. Nevertheless the capabilities of strip theory and 3D panel methods to simulate the dynamic responses of fast displacement hulls and semi-displacement ships need to be investigated more thoroughly. A study is presented on the numerical seakeeping assessment of conventional (displacement) and semi-displacement (semi-planing) monohulls which deviate considerably in terms of both the slenderness of hull form and the speed from the basic assumptions of classical seakeeping theories. The numerical results are evaluated using experimental data for a modern fast displacement ferry and a high-speed light displacement semi-planing monohull in regular head waves. The numerical results are discussed with respect to accuracy and validity as well as computational effort.

In many cases experienced naval officers have little difficulty in determining the best ship speed and heading to take for carrying out motion-sensitive tasks; however this is not necessarily the case conditions for a complex seaway that has multi-directional and-or multi-modal frequency characteristics or when conflicting performance requirements must be satisfied. 'Seakeeping operator guidance' is a methodology for obtaining and presenting the naval operator with information on ship motions in two distinctly different ways: the first is tactical operator guidance which provides information for planning the best ship tactics to adopt before performing motion-sensitive activities; and the second is real time operator guidance which monitors ship motions while the activity is actually being carried out in order to warn the operator when safe operating conditions are being exceeded or are about to be exceeded. An accurate definition of the wave height frequency and directional parameters is critical for providing reliable tactical operator guidance; however this is not easy to accomplish with existing shipboard sensors. A new methodology called wave data fusion is being considered to provide this capability and if successful it will enable the development of an integrated and reliable seakeeping operator guidance system.

An integrated tool for hydrodynamic optimisation of ship hull forms and its is presented. The objective of the optimisation process is a combined improvement of the calm water performance and sea-keeping capabilities. A design optimisation system is described. This system is based on the concept of parametric modelling which means that the hull shape is defined through a set of parameters that can be used to systematically vary the hull forms and to directly relate hull form to hull hydrodynamic performance. The tool incorporates robust CFD codes for the evaluation of the hydrodynamics and optimisation algorithms and techniques to help the designer identify the best design. A practical example of how the optimisation system can be used during a typical design process is discussed the chosen hull being a hard chine fast ferry; this makes an interesting case of multi-objective optimisation.

In this paper a methodology has been proposed to model the seasonal joint occurrence of metocean parameters. Two methods are proposed in order to derive an approximate joint distribution from the modelled margins. The first one matches the correlation matrix only whereas the second one which is based on a multivariate Hermite polynomials expansion of the multinormal distribution is able to match joint moments of order higher than two. However more restrictive conditions are shown by the latter. An application to the simple example of the joint occurrence of significant wave height and the mean wind velocity at the 10m elevation is used to illustrate the methods. Eventually examples of applications like simultaneous persistence of wind and wave conditions as well as seastate forecasting from statistics are given.

Int Conf held in London in 1989 Papers are Advances in the Riserless intervention for subsea well servicing Low-cost intervention Wirelining from a submerged support vessel Advanced and economic submersible support vessels Subsea multiphase boosting-review and future applications The first UK Subsea separator `Smubs'-the Shell Multiphase Underwater Booster station Cost reduction in satellite well systems Simulation of the electrical performance of inverter-supplied E.S.P systems The dynamic performance of subsea hydraulic control systems The VVK valve CAPJET-A simple and safe burial method for pipelines and cables An integrated subsea and topsides process control system The case for a downhole corrosion database North Alwyn Underwater(NAU)-testing installation and operation Subsea well control system without umbilicals-performance of the industrial prototype on a field test DISPS development and testing

This paper presents a summary of an investigation into the effects of hull flexibility when deriving an equivalent service factor for a single passage of a Great Lakes Bulk Carrier from the Canadian Great Lakes to China. The long term wave induced bending moment predicted using traditional three-dimensional rigid body hydrodynamic methods is augmented due to the effects of springing and whipping by including allowances based on two-dimensional hydroelasticity predictions across a range of headings and sea states. The analysis results are correlated with full scale measurements that are available for this sip. By combining the long term 'rigid body' wave-bending moment with the effects of hydroelasticity, a suitable service factor is derived for a Great Lakes Bulk Carrier traveling from the Canadian Great Lakes to China via the Suez Canal.

Provision of the undrained shear strength of dredged sediments during the consolidation phase is an important consideration during the design of confined disposal facilities because there may be severe instability phenomena during the application of external actions even of low intensity such as the placement of dry soil covers or vehicle transit. However when the dredged sediment consistency is still fluid it is impossible to collect undisturbed specimens for triaxial compression tests or direct shear tests to directly evaluate their shear strength. This paper presents a method to overcome this difficulty and indirectly evaluate undrained shear strength for dredged sediments as a function of their water content by means of relationships with the results of a simple and fast laboratory test the slump test. The analysis has been performed on sediments collected during dredging operations in Friuli Venezia Giulia (Italy) measuring their main geotechnical characteristics and forming mixtures with different water contents.

A high voltage cable is strapped to the flowlines on the HTHP Kristin field as part of the direct electric heating (DEH) system. The cable with its components has to function in temperatures above 100 degrees centigrade since it is connected to the hot flowlines. Four different candidate cable sheath materials were exposed to an accelerated ageing program that simulated the conditions the cable should survive during the twenty years lifetime. The materials were a stiff polypropylene (pipe grade) a rubber modified polypropylene a thermoplastic elastomer and polyvinylidenfluoride (PVDF). The test conditions were one year's exposure in 130 degrees centigrade oxygenated sea water. After the exposure the mechanical properties of the thermoplastic elastomer were significantly degraded and the surface of the material was greasy. The stiff polypropylene was not stable for a long term exposure at these conditions. The rubber modified polypropylene was an acceptable sheath material. The PVDF material was not influenced by the exposure and was the best ranking material.

This book reveals 5,000 years of maritime adventure in a new compact format. From the earliest dugout canoes and the boats of the Ancient Egyptians to the most technologically advanced battleships and cruise-liners, this is the ultimate guide to every aspect of the ship, and those who have sailed them. Find out all about the endeavours of the great explorers as they mapped the globe and discovered new worlds, you'll learn the impact ships have had on trade and industry and find out all the key historical conflicts in which ships played a vital role. Plus, take a look at seafaring for pleasure and trace fishing through the ages. Every conceivable type of sea-going vessel is featured, from caravels and galleons, warships and yachts to clippers and cruise-liners. Produced in association with the National Maritime Museum.

Preparing a specification for a new construction becomes a challenge when ships have to be built or modified from existing designs to suit the special requirements of the trade or areas of operation. Most vessels are constructed as replicas of standard models and are slightly modified to suit the company. Most of these are based on cost reductions offered as pay-back discounts. Whilst it is imperative not to exceed the budget capacities need to be contained and fitted properly within the cost structure so that the vessel operates efficiently to fulfil essential criteria. These criteria are listed and they are considered amongst other criteria in relation to the preparation of a construction specification. Verification tests and trials are described prior to delivery.

Ship stability information book for the M.V. Almar, which is a general purpose vessel, essentially a bulk carrier with a single decked hull. It has six cargo holds which are each closed by hydraulically operated end folding steel flap-topped hatch covers. Dual purpose tanks may be used for either clean ballast or fuel oil storage. Sections of the book are as follows: Ship profile and layout, Comments on loading, Hydrostatic particulars, Load lines, KN values, Capacities, centres of gravity and free surface moments of: oil fuel tanks, lube-oil and engine room tanks, water tanks, Capacities and centres of gravity of cargo spaces, storerooms and crew and effects, Cargo hold data and Ballast tank, Dual purpose tank and fresh water/feed water sounding tables.

Second edition ofShipping pools. The first edition describes methodically the working and administration of a typical pool, how liabilities are shared, income equitably weighted and distributed, and how the group or pool is promoted and marked. In addition, the author devotes individual chapters to accounting practices, insurance and indemnities, operations and the construction and contents of a pool contract. The second edition has been updated and expanded to include two additional chapters on contracts of affreightment and other freighting tools. The negotiation and operation of contracts of affreightment, nomination of cargoes and vessels, escalation clauses and the standard contract form INTERCOA are discussed in detail. Other market tools of particular importance such as parcelling/liner services, joint ventures, turnkey projects an freight futures are also covered.

Ship's rolling is caused by outside forces such as wind and waves. Rolling can be reduced using regulators. The most well known regulators are side keels and anti-rolling ranks. The influence of the side keel on rolling is considered. Fin stablisers one of the anti-rolling systems currently used are considered. To obtain optimum performance an appropriate regulator is required. A regulation model using fuzzy logic is presented. The fuzzy logic adaptive control unit is presented and its system structure is described. The rule block which contains the control strategy of a fuzzy logic system is also presented. Results are shown. It is concluded that the standard benefits to be obtained when a fin stabiliser is working optimally are: passenger comfort fuel savings roll reduction increased fin life and optimised control.

The book features colour photographs of shipwrecks on beaches, at ship breakers yards (in Alang Beach, Gujurat, India) or in rivers, all over the world (Angola, Australia, Egypt, France, Gambia, India, Indonesia, Ireland, Mozambique, Morocco, Namibia, Uganda, South Africa, Surinam, Tanzania, Western Sahara and Yemen). The vessels comprise of freight carriers, trawlers, warships, a lightship, liner, tugs, coasters. Some were sunk during the Second World War. Some interior photographs of cabins, bridge, radio room and some detail photographs showing corroded parts of ships. Photographs taken between the 1990's and date of publication. Ships are: Freighters: Independencia, Joaquim Kapango, Lundoce, Lepanto, Karl Marx, Noola, Louilla, Santa Maria, Hey Baroma, Tosei Maru, Heiwa Maru, Hongkong Surety, Licumbo, Licumbo, Jacaranda, Daora; Cargo vessels: Cherry Venture, Asahisan Maru; Trawlers: Shaunee, Aristea, Aristea, Otori Maru 8, Katsuei Maru 5, Meng Yaw; Fishing vessels: Geroi, Cabo Ledo, L'Elfe des Mers, Tuxa, Kolmanskop, Henrietta Spashetti, Han Cheng no 2, Tania, Meisho Maru 38, Phylisia; Coasters: Delfino, Donatella, Mito, Maoul, Plassey, Border; Other vessels: Maheno (luxury liner), Jonas (bulk carrier), Macuit (tug), Willem Eggerts (sailing vessel), Eduard Bohlen (steamer), SS Robert Coryndon (steamer), Seli 1 (bulk carrier), Romelia (tanker), Chanson de la Mer (yacht), Misty Moon (yacht), Kakapo (steamer), Pirantiny (steamer), Stellenberg (whaler), Edith Cavell (steamer), Mapinduzi (passenger and cargo), (freighter), Winnie de Pooh (yacht), Argos (patrol boat)

Submerged structures such as breakwaters or groynes can be responsible for the evolution of coastal morphology. They can modify the wave field and consequently restructure costal current patterns and sediment transport. A theoretical investigation into the effects of coastal processes in the presence of such structures is presented and a quantitative description of wave-induced currents and sediment transport patterns is provided. The approach is based on three numerical models: a linear wave propagation model; a wave-induced circulation and sediment transport model; and a one-line model for the prediction of shoreline evolution. Finally the range of operability and the optimal layout of such structures in terms of beach geometry sediment properties and the wave climate of a coast are rationalised.

Random wave run-up on beaches is an important coastal engineering and management issue. The limit of run-up defines the zone of wave action and thus can be used to determine coastal setback lines to design man-made beaches and dunes and to model beach and dune erosion during storms. Knowledge of run-up is also important in the prediction of crest height of coastal structures such as sea walls revetments and dikes. The analysis of random run-up data is presented. In the first part various wave computed run-up statistics are presented. In the second part the analysis of data for short-term distribution with distributions like Raleigh and Normal are presented. By using the least square method of regression it was found that Rayleigh was a better fit than the Normal distribution for the data collected off Mangalore coast. The analysis is described and conclusions are drawn.

A Silent Ship series article which introduces Centa Transmission's and Geislinger's new ranges of "silent" couplings said to reduce noise vibration and misalignment. Centa's Centralink the silent driveshaft was originally developed for cruise ships and ferries but has also been used on research and naval vessels to reduce vibration from torsional shaft oscillation and provide sound damping. The design compensates for angular and radial misalignment and axial end float. Gesilco Geislinger Silent Composite couplings have a low mass short coupling length and good sound insulation. Other characteristics cited are compensation for large misalignments transmission of high torques low and nearly linear reaction forces high permissible speed and no wear corrosion.