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Inmarsat regularly puts its FleetBroadband service through stringent maritime field evaluation (MFE) and earlier this year FB150 was put through its paces on board Skagern a coaster that found it could not depend on 3G connectivity alone.

Long-term records obtained by in situ seabed observatories and repeated CTD casts show the presence of a high energetic environment in and around two coldwater coral mound provinces at the SW RT margin and in the Gulf of Cadiz. In both areas coldwater corals are present on the mounds but the areas differ strongly in geological setting as well as in sedimentology and hydrography. Measurements of near-bed hydrodynamics as recorded with freefalling seabed observatories and water column observations show that currents in mound areas have a major influence on the presence of living coldwater corals and on the shape of carbonate mounds. While at the Southwest Rockall Trough margin a dense cover of live corals has been demonstrated only isolated living colonies and coral debris covered with mud occur on the mounds in the Gulf of Cadiz indicating that water mass properties and dynamics on the Southwest Rockall Trough are at the moment most favourable for coral growth.

This work focuses on the design of the new generation of semi-submersible platforms for oil and gas production offshore that is based on column square cross-sectional area. The platform column is based on an arrangement of stiffened flat panels having their ultimate strength characterised by buckling under in-plane compressive loading. Distortions induced by fabrication have considerable influence on the buckling behaviour and are discussed in order to provide design recommendations. This paper studies a segment of the column structural arrangement between robust transverse frames to analyse the failure behaviour of the stiffened panels. Previous research demonstrated the strong influence of both mode and magnitude of the geometric imperfection distribution as well as the boundary conditions. Numerical and experimental simulations for small-scale isolated panels are carried out in order to carry out a correlation study to adjust the numerical model for further use in more complex numerical simulations of the structural failure of the column arrangement. The stiffened panels are analysed to identify the buckling initiation on a particular panel and then the interaction between plates longitudinal stiffeners and the robust transverse frames during the progressive failure of the whole column.

Wave-impact related (slamming) loads can induce high stresses and cause deformation of local structural components. The accurate assessment of such loads is essential for the design of a ship's structure. Classification society rules contain formulas for slamming loads. Generally these formulae are adequate for conventional ships as they are based on operational experience. However for many modern ships it becomes necessary to resort to direct computations of slamming loads. A satisfactory theoretical treatment of slamming has been prevented so far by the complexity of the problem. Most theories and their numerical procedures were applied on 2D bodies; however slamming is a strongly 3D non-linear phenomenon that is sensitive to the relative motion between the ship and the water surface. Slamming is characterised by highly peaked local pressures of short duration. A numerical procedure to predict impact-related wave-induced (slamming) loads on ships is presented. The procedure was applied to predict slamming loads on two ships that feature a flared bow with a pronounced bulb hull shapes typical of modern offshore supply vessels. The procedure used a chain of sea-keeping codes. First a linear Green function panel code computed ship responses in unit amplitude regular waves. Wave frequency and wave heading were systematically varied to cover all possible combinations likely to cause slamming. Regular design waves were selected on the basis of maximum magnitudes of relative normal velocity between ship critical areas and wave averaged over the critical areas. Second a non-linear strip theory sea keeping code determined ship mot100094 Numerical prediction of model podded propeller-ice interaction loads

The Explorer of the Seas is the largest cruise liner class in operation today. She carries about 3000 passengers on weekly trips from Miami Florida to both the Eastern and the Western Caribbean and is also being used as a vessel of opportunity. This continuing relationship is expected to collect long-term time series data sets containing bi-weekly samples along the Caribbean cruise tracks. It is hoped that these data will reveal trends on shorter monthly time scales as well as on longer multi-year time scales. On board the EXPLORER there are Eco-Learning Areas for passengers as well as atmospheric and oceanographic laboratories and this makes the EXPLORER a notable departure from previous programs. In addition the installed scientific equipment is advanced and includes many meteorological and oceanographic sensors. Two RDI Ocean Surveyor Phased Array ADCP units are included in the sensor suite and were mounted in the ships hull during construction. The expectations of several of the principle parties involved in the creation of this venture are reviewed together with their opinions on the program's success to date in meeting those diverse expectations.

Detection and localisation of marine mammals at sea can be an important aspect of research and conservation. MMAD-MMAP (the marine mammal acoustic detection-marine mammal acoustic positioning) system is an automated marine mammal detection and positioning system. It has been successfully tested on AUTEC hydrophone data and will run on four or more hydrophones. Data sets with both 4 and 7 hydrophones have been successfully tested. The technique uses one of the received calls as the template to match with other calls on other phones in the array. The algorithm needs only search in time on detected signals. Results for pilot and sperm whales on a bottom-mounted array in deep water are presented. This approach is successful in detecting and localising pilot whales by their calls acquired on four phones spaced approximately 2 km apart. Sperm whale clicks pose a more difficult problem because of their simple structure and high repetition rate. The algorithm is relatively effective and could easily be implemented in a real time system.

Bilge water on ships is a mixture of discharges and leakages from a wide variety of sources directed to the bottom (lowest) compartment or bilge tank. Discharge of the bilge water generated on ships is a problem faced by all maritime operators. According to MARPOL regulations ships may only discharge bilge water containing less than 15 ppm of oil at sea. Oil and oily residues exceeding that limit cannot be discharged at sea and therefore are kept on board and discharged in the port receiving facility for treatment and disposal. The cost of treating bilge water by physical processes or by transportation to inland storage and disposal stations is very high. There is a need for a technology that can remediate the bilge oil on the ship itself and reduce the volume of waste oil being discharged at the port facility. SpillRemed and BilgeRemed are presented. These systems have been developed based on biodispersion technology to remediate bilge water on vessels and ships. These sytems are evaluated and the data is presented. The benefits of using this alternative technology in smaller boats and fishing vessels for treating their bilge water without using expensive oil water separators are considered.

For some time now there has been an increasing demand for redundant propulsion concepts. Perhaps once in its lifetime a ship might experience an event which is beyond its capabilities. This could be during a storm and propulsion could be lost and the ship might not be able to control its behaviour. This might result in lives lost or even a ship lost with the associated pollution consequences. Although most ships are not equipped with redundant parallel propulsion systems ship owners and shipyards have requested that major classification societies evaluate redundant propulsion concepts. Equipping ships with redundant parallel propulsion systems is cost to the operating company. Safety and business costs are considered and evaluated. It is concluded that although redundancy can dramatically reduce the probability of spill and can thus be seen as a major advance against environmental damage it is better to invest in people - to have a skilled man who can turn his hand to reducing the consequences of any accident.

In order to develop rational and transparent procedures for the structural strength assessment of container ships which can offer consistency of approach to shipbuilding marine and related industries as well as improve container ship safety a series of comprehensive studies has been carried out by ClassNK in recent years and some of the results are summarized in this paper. The comprehensive study on the design loads for direct strength assessment of primary structural members of container ships was firstly introduced. Secondly a comprehensive study on the method for torsional strength assessment of container ships is discussed based on the results from direct torsional moment analyses by a 3-D Rankine-source method and FE analyses of the entire ship structures. Lastly outlines of some basic studies such as 3-D numerical simulation for very strongly nonlinear ship-wave interactions in extreme waves full-scale measurements of hull response of a post-Panamax container ship in service etc. are also introduced.

A short review is given of the development of the techniques used for cavitation tests with propellers and reference is made to full-scale correlation work carried out on merchant ship propellers. The difficulties of making theoretical calculations on the inception and extension of cavitation on propeller blades are discussed with an emphasis on the influence of the leading edge radius on the pressure distribution for the blade profiles. An approximate method for such calculations is outlined and applied to some cases for which results of full-scale observations and model tests in cavitation tunnels are available. Agreement between calculation and experiment is found to be satisfactory. Calculations are made to investigate the influence of leading edge radius cavitation number radial circulation distribution and tangential velocities on the extension of cavitation.

Report regarding a series of explosions in the aft section of the carrier Berge Istra, which resulted in her sinking and the loss of life of all but two of her 32 member crew.

In the framework of the DeepStar CTR 4401A "Theme structures" coupled computations were carried out on a turret moored tanker based FPSO in 3000 ft6000 ft and 10000 ft water depth for the Gulf of Mexico. The FPSO was exposed to both Hurricane and Loop-current conditions. Using the DeepStar FPSO system a new set of computations in the time-domain has been carried out. By changing systematically the Cd-resistance coefficients on the risers and the mooring lines the effect of the coupling on the global motions and the mooring forces can be distinguished. The computations were applied for the system in 3000 ft water depth exposed to the Hurricane and Loop-current condition and in 10000 ft water depth during Hurricane condition. The results show that the complete coupling has to be taken into account to obtain realistic design values.

Migratory birds have been shown to use celestial cues and the geomagnetic field for orientation and seem to follow an inborn species-species magnetic compass course. The effect of long strong magnetic exposures on the orientation behaviour of both adult and second-year birds was investigated. The effects were examined of two types of magnetic treatments on the orientation performance of Common Redstarts (Phoenicurus phoenicurus) Lesser Whitethroats (Sylvia curruca) and Garden Warblers (Sylvia borin) during spring migration. The aim of the study was to expose the birds to a strong magnetic field and thereby temporarily disturb the birds' ability to perceive magnetic compass information by a magnetoreceptor mechanism based on magnetite. Materials and methods used are described. Results are presented and discussed.

Recent trends in naval architecture have indicated an interest towards increasingly larger vessels, the use of thicker plating and requirements to extend service life beyond 25 years. International welding standards need to address a new level of uncertainty that these structures introduce, and to continue to offer welding best practices to ensure that optimal fatigue resistance of ship structural details is achieved. This paper presents results of experimental and numerical studies conducted by Lloyd’s Register, aimed at defining the effects of weld penetration, root gap and misalignment on the fatigue resistance of cruciform structural details fabricated from steel. The investigation includes a literature survey on the subject from which relevant experimental data is incorporated to support recommendations. Based on the results obtained, recommendations are made for weld parameters and fit-up to achieve optimal fatigue performance, especially with regard to defining crack initiation location.

The terminal velocities of a single air bubble rising freely in stagnant seawater of 28.7% and 32.9% salinity and also artificial seawater of 34.1% salinity and distilled water have been measured for air bubbles on the equivalent bubble diameter from 1.5 to 5.4mm. Then the drug coefficient of single air bubble freely in stagnant seawater was looked into based on the measured terminal velocities. In addition the terminal velocities of a crowd of air bubbles rising in seawater of 28.7% salinity were also measured for air bubbles on the equivalent bubble diameters around 2.5 4 and 5mm. The experiments and results are looked at.

Sakhalin is an island located just to the north of Hokkaido one of the four main islands forming Japan. Offshore areas of Sakhalin are oil and gas rich. Commercial production of oil commenced at one of the oil fields the Sakhalin I2 in 1999. In 2001 the oil was imported to Japan. Resources from Sakhalin will be favourable to Japan which lacks domestic energy resources and is striving to widen potential sources of its energy supply. An experimental study was carried out at the ice tank of National Maritime Research Institute Japan on spreading behaviour of oil spilled under ice covers. Tests were performed for ice sheets with roughness on the bottom and for level ice sheets with a flat bottom. Test results for level ice sheets agreed well with a theory that takes into account effects of interfacial tension acting on the oil and oil buoyancy and viscosity.

From the point of view of mechanics trawls are considered as extremely flexible and partly extensible rope and net structures which are exposed to flow. Form and loads of such gears mainly depend on the corresponding velocity of inflow and also on the so-called rigging elements that are required for the horizontal and vertical spreading of the fishing gear. At the same time the fishing gear is acting on the surrounding fluid. These reactions can on the one hand lead to unsteady states in the fishing gear. On the other hand changes of pressure and velocity can be detected by the fish and can possibly influence the selectivity of the fishing gear. This paper is focused on the presentation of special numerical and experimental methods both for calculating large net systems and for analysing the reactions of the structure to the fluid.

Scattered short-time-scale observations are unlikely to capture the full spectrum of events that affect sediment-water exchanges - a persistent observational presence on the seafloor is needed. The Benthic Observatory and Technology Testbed On the Mid Shelf-Understanding Processes (BOTTOMS-UP) project was designed to measure the seabed response to physical forces acting across a spectrum of spatial and temporal scales. The observatory site is located 65 km east of St Catherine's Island Georgia on the broad southeastern US continental shelf. The activities of this are described in this article and initial observations from the sonar and five-beam vertical acoustic Doppler profiler (600-kHz VADCP) instruments to demonstrate the dynamics of water column-sediment interactions in an open continental shelf-setting are looked at.

Multiphase flows simulations using a robust interface-tracking method are presented. The state of the art of front tracking method a hybrid approach of the front capturing and front tracking technique proposed by Tryggvason et al. (1998) is considered. In the front tracking method a stationary fixed-adaptive grid is used for the fluid flow and a set of adaptive elements on the front is used to mark the interface. This method is based on solving a single set of Navier-Stokes equations for the whole computational domain by treating the different phases as one fluid with variable material properties. The fluid properties such as density and viscosity are updated based on the position of the interface. Interfacial source terms such as surface tension are computed on the front and transferred to the flow solver grid by using a dirac-delta function on the interface between the phases. The unsteady Navier-Stokes equations are discretised by a conventional finite volume scheme on the adaptive staggered structured grids and solved numerically. The interface or front is tracked explicitly by extracting the advection velocity from the flow solver grid. The advection of fluid properties is achieved following the motion of the interface or front. Hence