A skeg mounts from the stern of a towing vessel and extends below the waterline. A channel in the skeg protects cables for steamers and a source (e.g., air gun array) of a seismic system deployed from the vessel. Tow points on the skeg lie below the water's surface and connect to towlines to support the steamers and the source. A floatation device supports the source and tows below the water's surface to avoid ice floes or other issues encountered at the water's surface. Seismic streamers have head floats supporting the streamers. Each of the floats has adjustable buoyancy preconfigured to counterbalance the weight in water of the towed component that the float supports. Acoustic signals from a transceiver at the vessel find locations of the towed components. A towed fish at a lower level than the towed components also uses acoustic signals with a transceiver to further refine the locations of the towed components.

A skeg mounts from the stern of a towing vessel and extends below the waterline. A channel in the skeg protects cables for steamers and a source of a seismic system deployed from the vessel. Tow points on the skeg lie below the water's surface and connect to towlines to support the steamers and source. A floatation device supports the source and tows below the water's surface to avoid ice floes. The streamers can have vehicles deployed thereon for controlling a position on the streamer. To facilitate locating the streamers, these vehicles on the streamers can be brought to the surface when clear of ice floes so that GPS readings can be obtained and communicated to a control system. After obtaining readings, the vehicles can be floated back under the surface. Deploying, using, and retrieving the system accounts for ice at the surface in icy regions. In addition, handling the seismic record can account for noise generated by ice impact events.

A skeg mounts from the stern of a towing vessel and extends below the waterline. A channel in the skeg protects cables for steamers and a source (e.g., air gun array) of a seismic system deployed from the vessel. Tow points on the skeg lie below the water's surface and connect to towlines to support the steamers and the source. A floatation device supports the source and tows below the water's surface to avoid ice floes or other issues encountered at the water's surface. Seismic streamers have head floats supporting the streamers. Each of the floats has adjustable buoyancy preconfigured to counterbalance the weight in water of the towed component that the float supports. Acoustic signals from a transceiver at the vessel find locations of the towed components. A towed fish at a lower level than the towed components also uses acoustic signals with a transceiver to further refine the locations of the towed components.

A natural gas liquefaction vessel including an increased deadweight tonnage, as compared to a liquefied natural gas carrier (LNGC) of a comparably-sized ship, is achieved by reducing the LNGC's cargo capacity. This difference creates room on the port and starboard sides of cargo tanks to increase the size of the adjacent wing tanks. The increased size of the wing tanks occupy the space created by the reduced cargo tank size of the vessel and may support a larger upper trunk deck. The ballast wing tanks and smaller cargo tanks increase the deadweight available. With this approach, the larger upper trunk deck of the vessel is able to support an efficient floating liquefaction plant that improves the LNG value chain because it is capable of producing 2.0-3.0 MTPA in the footprint of a standard vessel hull, such as for example a Q-Max hull.

A skeg mounts from the stern of a towing vessel and extends below the waterline. A channel in the skeg protects cables for steamers and a source of a seismic system deployed from the vessel. Tow points on the skeg lie below the water's surface and connect to towlines to support the steamers and source. A floatation device supports the source and tows below the water's surface to avoid ice floes. The streamers can have vehicles deployed thereon for controlling a position on the streamer. To facilitate locating the streamers, these vehicles on the streamers can be brought to the surface when clear of ice floes so that GPS readings can be obtained and communicated to a control system. After obtaining readings, the vehicles can be floated back under the surface. Deploying, using, and retrieving the system accounts for ice at the surface in icy regions. In addition, handling the seismic record can account for noise generated by ice impact events.

Disclosed is a system comprising: a first, underwater, vessel provided with a substantially flat lower surface; and a second, surface, vessel, comprising a floodable well deck arranged to receive and accommodate the first vessel.

A hopper barge is disclosed. The hopper barge comprises a hopper compartment for carrying a plurality of containers, the hopper compartment comprising a hopper compartment deck. The hopper barge comprises an inner-bottom portion defined in part by the hopper compartment deck and a bottom portion of the hopper barge. A plurality of longitudinal bulkheads are arranged in parallel within the inner-bottom portion of the hopper barge. A plurality of transverse bulkheads are arranged in parallel within the inner-bottom portion of the hopper barge, the plurality of transverse bulkheads running perpendicular to the plurality of longitudinal bulkheads. A plurality of pedestal supports are affixed to the hopper compartment deck, wherein at least one of the plurality of longitudinal bulkheads intersects at least one of the plurality of transverse bulkheads at a position beneath at least one of the plurality of pedestal supports.

A propulsion system (102) for an aquatic vessel (100) is provided. The propulsion system includes a plurality of Magnus-type rotors (108) and a drive arrangement (147) for rotating the plurality of Magnus-type rotors. The plurality of Magnus-type rotors are operable to rotate about corresponding substantially upright axes. The propulsion system also includes a control arrangement (150) for controlling the drive arrangement to vary rates of rotations of the plurality of Magnus-type rotors. Each of the plurality of Magnus-type rotors includes a hollow region (116) therein. Each of the Magnus-type rotors is rotationally supported onto a support arrangement (118) which extends into the hollow region. The drive arrangement includes at least one motor (148) disposed in the hollow region and located outside the support arrangement such that the at least one motor is accessible for maintenance. Furthermore, the at least one Magnus-type rotor includes a ventilation aperture arrangement (132) for enabling an upward movement of air to occur in operation within the at least one Magnus-type rotor for ventilating and cooling the drive arrangement and/or other internal components.

A propulsion system (102) for an aquatic vessel (100) is provided. The propulsion system includes a plurality of Magnus-type rotors (108) and a drive arrangement (147) for rotating the plurality of Magnus-type rotors. The plurality of Magnus-type rotors are operable to rotate about corresponding substantially upright axes. The propulsion system also includes a control arrangement (150) for controlling the drive arrangement to vary rates of rotations of the plurality of Magnus-type rotors. Each of the plurality of Magnus-type rotors includes a hollow region (116) therein. Each of the Magnus-type rotors is rotationally supported onto a support arrangement (118) which extends into the hollow region. The drive arrangement includes at least one motor (148) disposed in the hollow region and located outside the support arrangement such that the at least one motor is accessible for maintenance. Furthermore, the at least one Magnus-type rotor includes a ventilation aperture arrangement (132) for enabling an upward movement of air to occur in operation within the at least one Magnus-type rotor for ventilating and cooling the drive arrangement and/or other internal components.

The invention relates to a method for producing a vessel hull (1) for use as a hull of an FPSO or FSO, comprising producing a vessel hull with a stern portion (2), a bow portion (3) and a central portion (4), arranging a deck (6) on the hull, for supporting processing modules, arranging hydrocarbon storage tanks inside the hull, providing the hull with an anchoring connection arrangement (7), characterized by arranging process module reinforcements (8) in the deck for supporting the hydrocarbon process modules, providing both longitudinal hull sides with mooring line connection reinforcements (9) at or near the bow portion, arranging riser connection reinforcements (10, 14) on one or more longitudinal hull sides, in between the mooring line connection reinforcements in longitudinal direction, for a riser balcony (28, 29), and providing the bow portion with turret reinforcements (11, 12).