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The recently completed Gyrfalcon subsea development project in Green Canyon Block 20 is the world's first 15000 (15k) psig subsea system and had many industry firsts associated with its development. Among those were manufacture and installation of the worlds first 15k subsea tree a record 12200 psig rated 6" (nominal) flexible riser a 15k rated umbilical and 12200 psig rated flying leads. Other firsts included the first 15k rated continuous methanol injection system a dome charged 15k subsurface safety valve and the first 15k subsea frac-pack completion conducted in the Gulf of Mexico. What is perhaps even more unique is that these firsts were accomplished by a small independent operator on a marginal field under tight budget restraints.

Flatfish have been the subject of scientific research since the beginning of the 19th century but information on specific habitat requirements of adult life stages is incomplete. This study investigates the association between benthic habitat and the adult life stage of three flatfish species (plaice sole and lemon sole). Data from groundfish surveys spanning nine years were used to identify three distinct site groups: sites where a species was consistently abundant sites of variable or low abundance and sites at which no fish were caught. Habitat parameters for each site group and species are described and analysed. Besides large-scale physical parameters the importance of structuring epifauna and prey availability was investigated. Materials and methods are presented and results presented and discussed.

Admiralty courts have traditionally rewarded salvors generously including bounty as a reward for dangers faced. English and American admiralty courts have led the way in encouraging mariners to save lives and property at sea. Salvage doctrines have been flexible enough to allow for changes in vessels technology cargoes commerce and public need. However the threat of pollution from large oil tankers is grave and those who salve them need to be properly compensated. Is recovery for liability salvage the answer? A valid salvage claim must traditionally contain three elements. There are partial or complete success in saving the vessel cargo or freight; from a marine peril; by services rendered voluntarily. What about a salvor whose actions although not leading to the salvage of the vessel or cargo save a shipowner millions of dollars by avoiding pollution liability? The arguments and legal authority a salvor can use to seek an award for liability salvage are provided. Cases discussed are Allseas Maritime SA v M/V Mimosa Ocean Services Towing and Salvage Inc v Brown and Hendricks v The Tug Gordon Gill. The relevance of the Lloyd's Open Form and draft Convention on Salvage prepared by the Comite Maritime International are also discussed.

HICUP a modular program developed for the Windows 95-98 operating system is presented. HICUP enables the user to predict in real-time the hurricane generated waves and coastal inundation at site-specific locations in Hawaii as a hurricane approaches. Its suite of program modules allows the user to input hurricane parameters to select specific coastal area of interest to compute hurricane wind-wave fields to model numerically wave transformation and wave setup on a 2D numerical grid of the nearshore and shoreline of a selected area and to predict the spatial extent of coastal inundation plotted over a USGS map of the selected area. Presently the software covers several sites but future development work will expand its application to other site-specific coastal areas.

Sound speed varies strongly with temperature depth and salinity. Ocean temperature and salinity themselves vary under various forcing functions. Thus sound speed is constantly evolving over large spatial and temporal scales spanning turbulent scales to synoptic scales. These large scales of variability make unconditional categorisation improbable. Sound speed maps help in planning more efficient environmental survey operations such as conductivity temperature depth (CTD) collections. Intrinsic profile attributes estimated directly from the profile such as the mean variance and derivative values are used in the clustering process separately or in conjunction with extrinsic attributes such as location and ocean floor depth. Examples are used to show that the underlying spatial boundaries of the cluster groupings identify regions where sound speed profiles are consistent. The process is easily tailored to multiple clustering based upon the spatial and temporal scales of interest or on generic properties of the individual profile. The sensitivity of the cluster boundaries and group statistics to the addition of new profiles or to changes in temporal and spatial scale defines a new environmental characterisation.

A critical aspect to address in the design of SCRs is the in-service fatigue endurance. In recent times installation of complete SCRs by reelship has been discussed but not yet performed due to concern over the plastic deformation of the welded pipe and its effect on fatigue performance. Coflexip Stena Offshore (CSO) therefore embarked upon a development programme to investigate the issue and to relieve these concerns held by the industry. The two and a half year development programme has been completed successfully and has qualified the CSO Reeled Steel Catenary Riser (RSCR). This paper presents a summary of the fatigue testing results.

This paper presents two high temporal resolution current measurement campaigns where the current is sampled and stored at a frequency of 1Hz. One of the campaigns also included high lateral resolution measurements. The measurements were part of the current measurement program conducted by the Ormen Lange project. The measurements are rather unique and the first successful campaigns of its kind on the Norwegian Continental Shelf. The main objective of these measurements was to measure the turbulence characteristics of the current flow. This was regarded as important input to the design of the numerous free pipeline spans in the Ormen Lange development resulting from the very uneven seabed in the area. A description of the temporal high-resolution current measurement campaigns and example of results are given.

During June 2002 the FGBNMS (Flower Garden Banks National Marine Sanctuary) and the USGS Pacific Seafloor Mapping Project have mapped around 2000 km2 of the northwestern Gulf of Mexico continental shelf. The mapping focused on select topographic highs that have been identified as biological features warranting protection from oil and gas activities by the MMS (Minerals Management Service). These are areas of interest for future biological and ecological investigations by the NOAA. Base maps were used to target dive sites during the SSE (Sustainable Seas Expedition). Data obtained during this project will contribute to the benthic habitat characterisation and assessment of the associated fish communities. The base maps will also be used for all future ROV and submersible missions to investigate these features. The multi-beam data has provided a base data layer for GIS (Geographic Information Systems) projects into which all future and historical data can be integrated and upon which future scientific investigations can be planned and implemented.

The possibility of using a particular waterjet propulsion system on conventional high-speed crafts (particularly hydrofoils and SES) is investigated. The main idea beyond this concept is to use a sub-jet unit driven by a permanent magnet electric motion contained in the hub of the sub-jet itself. The preliminary design procedure of the sub-jet and the synchronous permanent magnet motion are described. The propulsion unit is designed to optimise the efficiency of the propulsion; the electric motor is designed to undetake this task and to fit within the hub of the waterjet pump. Design guidelines for both sub-jet and electric motor are provided.

Umbilicals for ROV (remotely operated vehicle) applications are generally complex cables consisting of power conductors signal conductors and fibre optic units. As the operational depth of ROV systems has increased the focus has been brought to bear on reducing the outer diameter of umbilicals. A smaller outer diameter opens possibilities of smaller and more compact winch systems and of reduced hydrodynamical drag during operation. A development program is reviewed which aims to develop a thin-walled insulation concept. The target of this program is to establish a robust insulation system rated for a voltage of 4.5 kV (line- voltage) and with a total thickness in the order of 0.6 mm. Part of the scope has also been to develop a technical solution that can easily be applied to higher voltage levels (eg 6.6 kV). A conductor design has been established in which the power conductors have an insulation system comprised of conductor screen insulator and insulator screen with a total thickness of 0.6 mm. The insulation system is rated for an operating voltage of 4.5 kV and a continuous temperature of 100 degrees C. Its advantages are listed.

Insulation life testing of an ROV tether cable was recently undertaken to determine whether higher cable-operating voltages were possible for future ROV system designs and upgrades. The tests were performed on field-aged samples of 17.3 mm steel armoured electro-optical tow cable used in small deep ROV systems such as MBARI's Tiburon and WHOI's JASON. The test results showed that the cable was capable of long-term operation at higher voltages than presently used with these systems. Design work is now proceeding to incorporate this data into improvements in the power capacity of these vehicles. Firstly the basic architecture of ROV power transmission systems is reviewed. Then factors affecting the insulation voltage stress are discussed. After this the cable test methods are described. Finally the results of the tests are reported.

The safety of ships has been assessed to date by a subjective and qualitative certification system. This subjective evaluation is done after the scientific process of design construction and operation. In spite of this accidents still take place sometimes. These may be attributed to a number of causes some inherent problems and shortcomings in design and construction errors in operation and so on. To be able to quantify these and give a numerical shape many factors have to be taken into account. These can be assessed by safety audits inspections and scientific evaluations. EMI (electro-magnetic interference) EMR (electro-magnetic radiation) and HOE (human and organisational error) are all implied causes of environmental accidents. Accident analysis and casualty forecasting are one of the best means of investigation. It requires a multi-pronged approach to determine a safety numeral and simulation is used to assess SDE (structural design errors). HOE analysis is discussed and HOE indexing is explained. It is shown that HOE is now fully quantifiable.

A centrally located North Sea oil field with estimated reserves of 60 mmbls of oil and 160 bcf of gas equivalents with complex geology and reservoir characteristics forms part of a larger multi field development project. In order to ascertain the optimum development strategy for the project the Operator required a better understanding of the reservoir and production characteristics. The project to do this consists of five stages: project management and engineering mobilisation and well completions production third well tie in (and pilot water flood study) and future potential (full field development). An asset based strategic alliance was able to achieve the project objectives by applying a value engineering approach to optimise the use of existing assets; minimise and defer the commitment of capital and resources and to deliver dynamic reservoir data within the framework of a single incentivised contract. A semi-submersible based EPS (early production system) exporting production via subsea flow line to a dynamically positioned tanker was on-line 19 weeks after receiving project sanction.

The decline of the perennial seaweed Fucus vesiculosus L in large parts of the Baltic Sea has been ascribed to the indirect effects of eutrophication such as increased turbidity sedimentation grazing and occurrence of filamentous algae. The effects of these factors have been experimentally tested and the results are summarised in a new conceptual model. To be able to optimise and evaluate the potential of restoring Fucus belts it is necessary to know how eutrophication affects critical steps in its life cycle such as the attachment germination and early growth of germlings. The new conceptual model distinguishes between the effects on adult and junior life stages and the two reproductive strategies of Fucus are added.

The development of a Safety Case was undertaken at Stena Line for the operational phase of the HSS 1500 series to demonstrate that major potential hazards were reduced to risk levels which were as low as reasonably practicable and to provide the highest level of safety in the safe and efficient operation of the world's largest high speed craft. The skills and competencies required to achieve this are based on the new approaches of the ISM Code and STCW 95. Recruitment for the project team and certification training education and management skills are discussed. Definitions are given for the Safety Case itself and human error. Examples of policy and standard operating procedures used to create a safety culture within a fleet are given including: colour coding of passage plan weather reports berthing criteria STCW engineers familiarisation ship handling training Chief Engineer's briefing search and rescue procedures (SAR) maintenance of ship and equipment wake and wash and ISM code training.

The history of car carriers managed by the Swedish pioneer Wallenius Lines is described from Rigoletto and Traviata modified cargo ships able to carry 290 cars to the first pure car carrier (PCC) Don Carlos delivered in 1976 and Madame Butterfly with a capacity for 6100 cars. Other articles on car carriers include: Rapid expansion of the pure car carrier trade (a discussion of the small group of operators handling transoceanic vehicle export); Refining designs for cargo flexibility (a description of purpose-designed multi-deck pure car carriers exploiting ro-ro cargo handling systems); New tonnage for shorthaul services (a description of Autopremier booked from Firsian Shipyard Welgelegen in the Netherlands for United European Car Carriers - UECC); and Deepsea ro-ro carriers target PCTC role (a description of the Mark III multipurpose ro-ro carrier Taronga handed over to Wilhelmsen by Mitsubishi in 1996).

The Sea Shadow is an innovative A-frame SWATH (small-waterplane-area twin-hull) ship developed to explore a variety of new surface ship technologies. These include ship control structures automation for reducing manning sea keeping and signature control. The effort to develop as efficient a hull as possible subject to some conflicting requirements of the various disciplines is described. Kelvin wave theory wave resistance and the basic optimisation technique are introduced. Three computational models of increasing sophistication which were required to obtain satisfactory predictions are discussed. The model and full-scale measurements of the wave pattern and wave resistance are presented followed by as section on the various ways in which lift was manifest throughout the flow surrounding the Sea Shadow. Finally two optimisation examples are given - the design of a 12-metre sailing yacht and a prototype forebody for a naval auxiliary ship. Three appendices described the one-tenth-scale Sea Shadow model the resistance and propulsion experiments and their results and the propeller disk wake survey.

The hull girder strength of permanently moored tanker-based floating production storage and offloading (FPSO) vessels require special consideration in areas subjected to severe weather. The methodology and results of hull girder strength studies performed for a typical 140000 DWT tanker are examined. The limitations of state-of-the-art software for analysing wave loadings on moored ships are discussed in terms of pitch motions hogging and sagging mooring system loads and the definition of still water allowables. Other seakeeping issues such as green water and bottom slamming are also highlighted. It is concluded that a typical 140000 DWT tanker has sufficient hull girder strength to serve as a permanently moored FPSO in severe sea conditions.

Tanker-Based FPSO (floating production and storage offloading) units have been regarded as a promising concept for an economic oil production in deep and remote areas since they have more storage capacity (no pipelines) and wider deck space giving better layout flexibility. In the present study the global performance of 6000-ft FPSO with taut chain-polyester-chain lines and steel catenary risers in a non-collinear 100-yr Hurricane is investigated in the time domain using a fully coupled hull-mooring-riser dynamic analysis program. The vessel motions and slender-member dynamics are solved simultaneously in a combined matrix to fully account for their dynamic interactions. The use of Newman's approximation is compared against more accurate results with full QTFs. The coupling and damping effects of risers on hull motions are assessed.

Methods are presented that have been developed for estimating joint PDFs (probability density functions) of statistically dependent features from sparse data with the main focus on computing likelihood functions for classification. Methods are limited to those that use marginal probabilities as building blocks. The estimators studied are (1) semi-parametric models and (2) nonparametric expansion models. A particular semi-parametric model with a MVG (multi-variate Gaussian) for Mn (pseudogauss) was studied. It was found that the expansion model was practical only for the inclusion of two-point terms yet it often captured much of the effect of the full distribution. The non-parametric models were made robust for classification by smoothly mixing in the marginals in poorly sampled regions. Because the models considered have multiple components we collectively refer to them as hybrid models.