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This paper describes the phenomena of 'Ship Squat'. When a ship proceeds through water, water is pushed ahead of it. In order to not leave a 'hole' in the water, this volume of water pushed ahead must return down the sides and under the keel. The streamlines of return flow are speeded up under the ship. This causes a drop in pressure, resulting in the ship dropping vertically in the water. As well as dropping vertically, the ship trims forward of aft. The overall decrease in the underkeel clearance forward or aft is called 'Ship squat'. It discusses its growing importance and lists the signs that a ship has entered shallow water. The main variables are discussed, together with one global formula for all conditions and two enveloping formulae for quickly estimating the value of ship squat. In conclusion, it is shown that ship squat is linked not only with ship safety but also with ship economics.

The application of conventional shore-side management principles to marine engine room operations has resulted from the redefinition of ships as strategic units in an increasingly regulated business environment. The use of engine room simulators in training marine engineers to apply these principles to engine room management is discussed with attention to simulator types and features of course design: the advantages and limitations of using simulators are also considered as is the effectiveness of the training. An illustrative example describes the Engine Room Management course offered on the full-mission simulator at the Maritime Operations Centre (MOC) Warsash UK. Potential future developments are outlined.

Second Int Conf held in Sept 1976 Papers are The laying of heavy moorings Standby safety vessels attending offshore installations Use of concrete as a hull material for offshore vessels Ocean towage and salvage - a colourful past an active present and a challenging future Collision avoidance and integrated navigation system for tug and supply boats New survey and support craft requirements for offshore pipelaying operations Mooring of supply vessels to offshore installations Design criteria for drillships Waste disposal at sea Offshore craft as submersible and dive system support craft Pilot boats for offshore services Offshore protection vessels An operators view of service craft Thrusters for dynamic positioning Service/support vessels for offshore oil/gas production Sophisticated autopilots for offshore applications The chartering of cargo barges for offshore industry Manpower for offshore technology Weather forecasting for North Sea operations Safe manoeuvring of supply ships - a contribution Ropes for offshore service

Adhering to the guidance of good mooring practice should generally ensure safe mooring of ships. Computer predictions in combination with scale model tests for validation may be helpful in cases where it is difficult to stipulate accurately the external loads acting on the moored vessel. A mooring system should resist forces due to wind and current surges from passing vessels and the effects of waves swells seiches and ice and tides. The layout of a pier or sea island to permit safe berthing and mooring is specified by the spacing of breasting dolphins the location of mooring dolphins and the placement of spring line bollards. Mooring equipment includes wire mooring lines winches (including winch brakes) chocks and pedestal rollers. Prediction of moored ship behaviour can be made using mathematical models. First- order ship responses at wave frequencies are modelled as linear responses to harmonic waves using response functions due to waves of unit amplitude for the six degree of freedom motions of the ship in waves. Low-frequency ship motions in surge sway and yaw are modelled as responses to wind current and wave drift forces. Comparison of computer models with full-scale observations and measurements should continue.

An outline of a theoretical computational analysis is presented which allows prediction of the hydrodynamic pressure induced on nearby surfaces when a propeller experiences transient cavitation as it rotates in a ship's wake. The theory applies unsteady three- dimensional and quasi-steady two-dimensional cavity hydrodynamics for both partially and fully cavitated foil sections in terms of parameters determined from a three-dimensional unsteady flow theory for a propeller in a wake. Computational considerations taken into account during the development of the computer program are discussed. The use of the approach is illustrated by comparing theory with measured data in water tunnels and on full-scale ships.

The analysis of local flow phenomena is a basic need for the development of an efficient oil recovery system such as the Seaway Independent Oilskimming System (SOS). As the oil separation process is highly dependent on the ships' motions its seakeeping behaviour needs to be simulated accurately. This paper presents two-phase flow simulations (air water) of the seakeeping behaviour in three and six degrees of freedom (two- and three-dimensional - 2D/3D). The vessel motions simulated in various sea states are validated by model tests conducted in a physical wave tank. The grid resolution as well as the flow parameters of the simulation have been varied to find a fast and reliable solution. The need for three dimensional simulation runs is questioned. Oil is introduced as the third phase. The associated analysis illustrates the oil-water separation process and yields the systems efficiency in dependency of the sea state conditions. Based on the results of three-phase simulations the operational range of the Seaway Independent Oilskimmer is determined and recommendations for the system optimization can be made.

There has been a trend in recent years to equip ships with larger thrusters capacity in order to improve manoeuvrability and reduce the need for tug assistance. Developments in tunnel thrusters are outlined including basic design features controllable and fixed pitch propellers and noise and vibration control for side thrusters. The use of frequency controlled electric motors for thrusters is discussed. It was shown that the fuel saving with this drive motor option does not justify the required added investment costs unless yearly operating time is very high. If a variable speed solution is selected the controllable pitch propeller gives additional fuel saving and offers other benefits. Various measures to reduce noise from tunnel thrusters are reviewed. The most effective treatment is to isolate the thrusters installation from the hull structure by using a resiliently mounted thrusters. Developments in retractable thrusters are briefly presented.

No other ship or maritime tragedy holds more fascination than the Titanic - and a century after she sank beneath the chill, starlit North Atlantic waters on her maiden voyage, carrying a wide mix of passengers, from the social, artistic and financial elite of two continents to the humblest emigrants on their way to America, the story continues to enthral people of all ages and cultures.Two of the world's foremost authorities present this popular account of the sea s best-known disaster, expertly summarisizing the ship's brief but glamorous life, from building and launching in Belfast, to the discovery of her remains more than two miles down on the ocean bed, and the subsequent artefact recovery dives and courtroom efforts to protect the wreck. Their own photographic dives to the wreck site feature in this updated third edition of their best-selling paperback, together with a wealth of fascinating new information about the ship and her people, past and present.

Manpower costs generally constitute more than 50% of the through-life costs of a warship. This paper explores ultra low-manned and unmanned warships as components of the future affordable fleet. Methods are described that have been developed by TNO and the Royal Netherlands Navy to automate firefighting and to enable a ship to be designed that is inherently able to withstand damage without immediate crew intervention. A small core crew can be enhanced by specialist teams for specific functions such as the operating of helicopters and the deployment of special forces. The new Dutch Patrol Frigate and the US Navy Littoral Combat Ships are examples of warships with core crews of about 50 personnel with provision for embarking another 50 people in specialist teams. When the ambitions of NEC (network-enabled capability) and CEC (co-operative engagement capability) have been realised the way will be open for an ultra-low-manned warship to become an unmanned warship. The paper describes the benefits of such a vessel and the uses to which it could be put so that it becomes a valuable component of the affordable future fleet.

The towline tension and unstable motion of disabled and damaged ships is investigated using a geometrical model ship in a towing experiment to establish the estimation method of the towing force and towing method. The towing experiment was carried out both in still water and in waves. The towing resistance coefficients on various kinds of conditions such as towing direction towing speed ship status and towing points were compared in still water. The unstable motion both in regular and irregular waves was also compared with that in still water for sway amplitude yaw amplitude and yaw period. The towing experiment was carried out for both following waves and head waves. Both the unstable motion and the towline tension increase in waves were investigated experimentally.

The Memorandum of Understanding on Port State Control in the Asia-Pacific Region (Tokyo MOU) which came into effect in April 1994, provides for that the maritime authorities in the region co-operate closely to eliminate substandard shipping and to promote maritime safety and protection of the marine environment in the region. The promotion of the PSC Officer Training Course is an essential element for the effective implementation of Tokyo MOU and to ensure uniformity and consistency in port state inspections in the Asia -Pacific region. This textbook is for the use of in-class lectures as well as for the distance education undertaken at officers' own country prior to the intensive course. Contents cover the need for control, the main elements of the convention requirements, documentation, inspection of ships, action by the port state and practical port state control training.

Cleaning oily wastewater poses distinct challenges. The composition and flow of the wastewater changes over time making efficient treatment difficult while also meeting requirements for safety reliability and compactness. Today heightened environmental and economic concerns have sparked an effort to reduce the volumes of all waste streams onboard that require treatment and-or disposal. An integral part of this work is the reduction of onboard chemical consumption. Centrifugal separation has proven to be an efficient oily wastewater treatment technique to efficiently remove oil and other contaminants with a goal of handling emulsions and reducing the oil content in the clean water discharge to between 0 - 5ppm. By diminishing the environmental impact with its proven reliability centrifugal separation is unmatched by other high-maintenance labour-intensive oil separators. Alfa Laval's EcoStream system is presented. This is a fully automated single-stage centrifugal separation system for the treatment of up to 580 gallons per hour onboard ships and up to 1320 gallons per hour for land-based applications. The challenges related to bilge water treatment and different methods available to break emulsions are also described.

The first modern work to give a comprehensive picture of the RMS Titanic and the people intertwined with her fate, from disaster to recovery. Drawn from primary sources and contemporary accounts and updated to coincide with the April 2012 anniversary, this new heart-rending narrative allows readers to come to their own conclusions about this legendary vessel.Daniel Allen Butler spend more than 30 years researching the work, delving into the lives of every principal participant. In addition to examining the roles played by individual, he also looks into the problems of equipment and errors in technical data that resulted in the deaths of 1502 people. Rather than focussing on the night of the tragedy alone, he also investigates the events leading up to and following the fateful night.

UUVs (untethered unmanned underwater vehicles) have entered the commercial market and have shown the ability to perform deep-water surveys faster and cheaper than towed vessels. The UUV team concept is presented. A stereotypical UUV team would be a heterogeneous mix of several low-cost specific purpose vehicles guided and supported by one or two higher cost control vessels. However precision underwater navigation is difficult due to the severe restrictions that the sub-sea environment places on communication and positioning. Currently most precision underwater navigation relies on some sort of infrastructure such as surface ships or underwater beacons placed in known positions. Using these assets as reference-points sub-sea navigation is carried out. Some situations require that the environmental and-or commercial attributes of an area be assessed before an infrastructure exists. In order to do this the UUV team must be able to navigate to an area carry out its task and return without any pre-existing infrastructure or step by step guidance.

The serving process in a port must be large enough to avoid long queues of ships or loss of customers but not so big that servers are unoccupied. A mathematical model that analyses the serving process in the Port of Thessaloniki is presented. The model employs both queuing theory and mathematical statistics. The number of servers for the port is shown to be sufficient in one part and more than optimal in others. Forecasting techniques conclude that development of the port should not include additional servers at this time.

A wave load mechanism which can be dangerous for a bow visor construction similar to that on the Estonia is investigated theoretically. Linear model of wave motion and second order Stoke's wave conditions for wave breaking calculation of a ship's motions in waves and estimation of slamming forces due to a breaking wave are discussed. Large bow submergence occurs in most cases correlated to the wave crest. A major submergence of the bow visor in combination with a breaking wave can be the hydrodynamic mechanism resulting in a sufficiently large slamming force. This problem can occur on ships of the same size as Estonia in a sea of significant wave height greater than 6m. The probability of this kind of slamming impact can be calculated by a Monte-Carlo type simulation in combination with the crest-height acceleration threshold method.

The container market has become one of the major shipping markets in the world but the demand pattern and the demand for ships in the future are being changed with the introduction of post Panamax container vessels feeder systems and a substantial increase in the reloading of containers (hub systems). Large operators are working through alliances aiming to integrate sea transport port services and land transport to their customers. More can be squeezed out of the liner industry in terms of lower transportation cost per unit and growing competitiveness with new participants likely to enter the scene from Latin America Middle East and Africa based on cheap second-hand tonnage services.

The basic principles and procedures of Port State Control are explained with discussion of its role in ensuring maritime safety and environmental protection by the enforcement of international conventions within its waters and its purpose to eliminate substandard ships by inspection and detainment. Regional co-operation on Port State Control adopted as a means of increasing its effectiveness is considered with brief comparative details of existing regional systems formed by the Paris Memorandum of Understanding (European States) the Acuerdo de Vina del Mar (Latin American States) and the Tokyo Memorandum of Understanding (Asia-Pacific Region). The importance of the human element in marine safety is stressed with recent and on-going amendments to IMO Conventions to accommodate this outlined. Anticipated developments are considered.

Impact loads on ships resulting mainly from bow slamming but also from green water on deck may induce global transient hull vibration known as whipping. This phenomenon occurs in heavy weather mainly in head or bow waves and the related global structural loads contribute to the maximum vertical bending moments induced on the ship structure thus it needs to be taken into account for the definition of the design wave bending moment. The numerical model is presented which calculates the vertical loads induced on the ship structure by large amplitude waves. This includes: the non-linear time domain method to calculate the rigid body ship responses the impact theory and the momentum method used to calculate the slamming loads on the ship bow the modal analysis procedure based on a finite element model of the Timoshenko beam and the calculation of the transient hull response.

In the winter of 1999-2000 a group of Russian Korean Japanese and American scientists conducted an international program to investigate the oceanography of the Japan/East Sea and its surface forcing. During this program atmospheric observations were made with a research aircraft and ships to understand the lower atmosphere and surface air-sea fluxes. In this article several highlights are reported of these investigations with a focus on the dramatic severe cold-air outbreaks that occur three to five times a winter month. A start is made with a refresher on the physical setting and the winter mean and synoptic conditions. A description is given of the marine boundary layer and air-sea interaction based on research aircraft and ship measurements. Lastly a look is taken at numerical model simulations that illustrate the special role of coastal topography on the surface wind field and air-sea fluxes over the Japan/East Sea.