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Seventh symp held in Bath 24 - 27 Sept 1984 Papers are Digital progress in the Royal Navy US navy control systems overview Machinery control initiatives - a Canadian perspective Ship automation - a Dutch view on practice and progress Digital control and surveillance system for the M- class frigate of the Royal Netherlands navy Propulsion control in the Swedish M80 class mine countermeasures ships Practical experience in the application of microprocessors to machinery control and surveillance Multivariable adaptive control of ships motions A classical approach to a microprocessor based PID autopilot design Modal tests and full scale trials with a rudder roll stabilisation system

Identification of MLOs (mine-like objects) is a pressing Fleet need. During MCM (mine countermeasures) operations sonar contacts are detected and classified as mine-like if their signatures are sufficiently similar to known signatures of mines. Currently this time-consuming identification process is carried out manually by EOD (explosive ordnance disposal) divers or ROVs (remotely operated vehicles). Rapid visual identification of MLOs using electro-optic identification sensors will dramatically improve MCM operations. To support rapid visual identification two EOID (electro-optic identification) sensors are currently under investigation by the Navy. EOID sensors produce 2D and 3D images for use by operators and algorithms to make the all-important decision regarding use of neutralisation systems against sonar contacts classified as mine-like. The quality of EOID images produced can vary dramatically depending on system design operating parameters and ocean environment necessitating the need for a common scale of image quality or interpretability as a basic measure of the information content of the output images and the expected performance that they provide. Two approaches have been identified for the development of an image quality metric.

The book looks at alternative feed stocks for the production of synthetic liquid fuels, for which the need has arisen on account of the shortage of petroleum. It particularly examines coal, tar sands, oil shales and cellulose and occlated organic compounds. The processes available for coal conversion are described in detail and their energy requirements reviewed. A more limited treatment of other fossil fuels is included and cellulose is included as a renewable resource. It looks at the economic costs of the conversion processes and of synthetic fuel production.

A brief overview of several significant technological advances related to production development in ice-infested water is given. Monitoring of full-scale ice interactions in combination with research programmes has resulted in large design load reductions. Development of an ice loads database the Hans Island Multi-year Impact Experiments and geotechnical monitoring are discussed. A major full-scale and partial-scale steel testing programme has resulted in considerable weight and cost savings for Arctic structures. The details of different structure types for three different regions Canadian Beaufort Sea Pechora Sea and Canadian East Coast are presented. A cost-effective Arctic class year-round shuttle tanker and loading system has been designed based on recent advances in Arctic transportation.

The warfighter should not be concerned with environmental protection as he strategies or trains for conflict. Navy ship program managers must consider environmental protection as a fundamental element of their program since a ship that is designed to be environmentally sound is inherently operationally flexible. Environmentally Sound Ships enhance crew quality of life enable unrestricted operations are easier to protect in port and avoid costs over their life. Environmental protection is often overlooked until the very end of system design and is often 'tacked-on'; not integrated into the design leading to less than optimised solutions. Early adoption of the straightforward basic management principles of an EMS (Environmental Management System) affords the Program Manager with a transparent process for defining requirements and budgeting and executing required resources to ensure that the system is fielded fully capable to meet warfighter needs. The successful implementation of the Secretary of Defense FY 2001 Environmental Excellence in Weapons System Acquisition Award winning Lewis and Clark (T-AKE 1) Class ISO 14001 certified EMS in the context as a risk management tool is discussed.

Polyamide PA-11 is a workhorse polymer within the flexible pipe industry performing many important functions in inner sheath outer sheath and other applications. Its use is however limited by degradation at elevated temperature in the presence of water and acidic environments. Over the past decade there have been multiple industry efforts to advance the understanding of this degradation process. This paper provides a review of the recent activities of an industry work group - the so-called Rilsan User Group - which has attempted to co-ordinate these activities. The main aim of the Group is to provide more detailed guidance on the use and limitations of PA-11 and develop a common industry accepted procedure for predicting the service life of PA-11 pressure sheathes.

Preliminary discussions of the relationships between powering, hull type, and propeller size and shape lead into a chapter on an intuitive method of propeller selection (the Crouch method) followed by a chapter with a more scientific approach. The author has created charts and graphs that enable the user to ender his boat’s speed and powering characteristics and find the optimum propeller pitch and diameter quickly and conveniently. Topics also included: treatment of propeller installation, recommended shaft sizes, shaft angles, bearing distance for such diverse boats as tugboats and trawlers, sailboats, high-speed outboards, stern drives, and motorsailers.

Many marine animals have developed an impressive ability to move efficiently underwater. The most common means of their locomotion is the use of flapping foils or oscillating tail fins. This kind of relatively large amplitude rhythmic unsteady body motions can achieve high efficiency and outstanding manoeuvring agility. The research into this new swimming mechanism can potentially provide inspiration for design of propulsive systems that will outperform the thrusters and propellers currently in use. The advantages of noiseless propulsion associated with a less conspicuous wake could be particularly useful for military applications. Here the unsteady hydrodynamic characteristics of 2-D flexible flapping foil in the viscous flow field are studied based on previous work. The performance of the flexible caudal fin a new type of propulsor applied in the small underwater vehicles is studied.

Offshore oil and gas production have both risen substantially over the past ten years and their shares of total world oil and gas output have grown similarly. Most of the growth in offshore oil and gas production has occurred in the North Sea particularly in the UK and Norwegian sectors. Forecasts for the period to 1999 are compiled on a country-by-country basis and then aggregated for the regions and for the whole world. Seven key indicators are used: oil production gas production exploration activity and expenditure disaggregated by exploration expenditure development expenditure and production (operating) expenditure.

This paper presents results of research performed at the Krylov Institute in support of the development of a planing catamaran with asymmetric demihulls using the artificial cavity concept. It offers a comparison of resistance model test data from two design options: with traditional smooth hull lines and with air cavities on the bottoms. Experimental results demonstrate that artificial cavities make it possible to reduce the catamaran resistance by about 20% with only minor power losses for the air supply. The project also includes estimating the amount of air to be delivered into the cavities and assessing the effects of head and following waves upon seakeeping performances of the catamaran model.

The pull-out capacity of bucket foundations in soft clay subjected to inclined loading is considered. Results from a parametric study involving 3D finite element analyses of bucket foundations in which the diameter skirt length soil-structure adhesion and inclination of loading are varied are presented. The soil is assumed to be an isotropic soft clay with an undrained shear strength increasing with depth. It is shown that normalising the results with respect to the maximum vertical force (obtained from an analysis involving only vertical pull-out) leads to a unique interaction diagram which is independent of the foundation dimensions. The implication for design is that once the vertical pull-out capacity has been evaluated it is then possible to determine the capacity under any inclined loading without additional complex 3D analyses. This study forms part of a larger research project in which the effects of soil anisotophy on the behaviour of offshore foundations are under investigation.

Compiled by The British Pump Manufacturers Association. This handbook places emphasis on the importance of correct interpretation of pumping requirements, both by the user and the supplier. Advice is given to users to enable them to make requirements clear when communicating with manufacturers. The suction performance of pumps and associated problems, like sump design, are treated in detail and a special chapter is devoted to self-priming pumps and allied priming problems. The following chapters are included: Main classes of pumps (rotodynamic, positive displacement, self-priming), How to make liquid flow into pump, Defining the total pump head, The stuffing box, Choice of materials, How to enquire for, select and order pumps, Electric pump drives, Piping and conduits, Pressure surges and their control, How to test pumps, Installation and preparations for operating pumps, fault finding. There are 2 new chapters for this second edition: 'Hints for Users' and 'Health and safety'.

This handbook places emphasis on the importance of correct interpretation of pumping requirements, both by the user and the supplier. It aims to enable the reader to understand the principles of pumping, hydraulics and fluids and define the various criteria necessary for pump and ancillary selection. Sections comprise of: Basics (fluid mechanics principles and criteria for pump selection), Kinetic pumps, Positive displacement pumps, Pump construction (materials, corrosion, seals and packing), Testing, installation, vibration and balancing, Drives, Applications (water, fire, chemical process, food, pharmaceutical, petroleum, paper, solids and waste pumps). Section 8 is an appendix containing useful diagrams and tables. The last section is a guide to buying pumps.

Modern offshore developments frequently tie subsea wells back to other structures. Control of the subsea templates requires extensive use of electro-hydraulic umbilicals with large centre tubes for methanol glycol and chemical injection. High-pressure spoolable composite tubes are an alternative to other construction materials for large centre tubes. The development and completion of a qualification programme for a static Large Centre Umbilical (LCU) with a spoolable composite centre tube is reviewed. Development of the umbilical for deepwater applications is also discussed. The qualification program is based on NORSOK requirements and Alcatel in-house requirements. The product is now commercially available.

The Royal Australian Navy Hydrographic Service's (RANHS) Laser Airborne Depth Sounder (LADS) was introduced in the early 1990s and is now a well established system used for routine hydrographic surveys of the coastal zone. In 1998 a program was initiated to improve the quality control (QC) process through the acquisition of a 3D interactive visualization system. For this purpose the Fledermaus 3D visualization application was chosen and combined with the latest Silicon Graphics Octane workstation. First some background information on LADS is given. Next data visualization is considered. After this the LADS QC tool is looked at.

It is becoming imperative that The Formal Safety Assessment (FSA) studies now being conducted for the development or upgrading of future Rules are based on systematic quality management principles to avoid a wide variation in the quality and conclusions from the FSA process. The five-step FSA process is considered suitable for application of the "process approach" as per ISO 9001:2000 requirements. This application of the Quality Management Standard would ensure that the quality objectives of each of the Steps are identified and attained through use of appropriate techniques and data by the FSA team. The paper presents a proposal for the application of the above quality management methods to the FSA procedures using a 'process approach'. Typical 'Process Flow Diagrams' for the various steps of FSA process along with the quality parameters are included in the paper. A proposal for internal validation of an FSA application prior to submission to the decision makers is also covered in the paper.

Various methods are presented to characterize uncertainty due to imperfect force prediction models. These use different statistical approaches to systematically compare "true" and predicted load levels. In particular the reporting of marginal error statistics (e.g. mean bias and uncertainty) is shown to be generally insufficient to recover the marginal distribution of applied loads as required for reliability analysis and design. Methods are shown to address this insufficiency through regression-based analysis and comparison of ordered loads data. While results specifically consider fluid drag loads the methods are intended to have wider applications: e.g. to statistically compare actual wave heights with those based on hindcast methods.

Experience has shown that safety problems on offshore platforms are associated with human and organisation factors (HOF). These factors should be included in risk analysis evaluation and management processes. Three approaches to HOF risk management are presented and discussed. The first is to reduce the incidence and severity of HOF. Second is to reduce the effect of HOF. Third is to increase the detection and removal of HOF. A good risk management programme will employ all three approaches in balance. The engineering evaluations of platform safety are qualitative risk analyses such as Hazop (Hazard and operability analyses) and FEMA (Failure Modes and Effects Analyses) quantitative methods such as QRA (Quantified Risk Analyses) and PRA (Probabilistic Risk Analyses) and mixed qualitative-quantitative analyses such as Safety Indexing Methods (SIM). These are described together with their individual strengths and weaknesses. A hypothetical platform audit is described to highlight areas of potential weakness in safety.

Three random dynamic analysis approaches are used to carry out the structural analysis and the fatigue verification on some joints of a jacket type offshore platform. One is the frequency-domain approach another is the time-domain approach and the third is a hybrid method. Firstly some background information is given. Next random fatigue analysis phases are touched upon. After this structure's dyanamic random analysis and random fatigue analysis are each considered in turn. Lastly application is looked at.

The rates and patterns of fluid circulation in seafloor hydrothermal systems control the efficiency of lithospheric heat extraction the nature of fluid-rock interaction and the extent of seafloor and sub-seafloor biospheres supported by fluid energy and solute fluxes. Newly developed tools have led to important advances in determining the patterns and rates of fluid flow within seafloor hydrothermal systems. Here rates of fluid flow in hydrothermal systems the lateral extent of circulation preferred directions of fluid flow and the "shapes" of fluid pathways are discussed. Techniques applied include the use of thermal and chemical tracers seafloor and borehole observations and coupled modelling. Although focusing on ridge flank hydrothermal systems limited observations and inferences from studies of ridge crest systems are also presented because crustal properties acquired at the ridge are likely to have continued influence as the seafloor evolves.