Abstract: A buoy (1) has a main body (5) and a moveable mass (2) positioned inside the main body. The buoy may be tethered to a submarine vessel and used as a communications buoy. The buoy may be configured for floating in a generally upright orientation at the water surface (7) in a position ready for communication, when the mass (2) is in a first position (FIG. 1a) in which the center of mass is offset from the center of buoyancy to improve stability in the water. The buoy may be configured for being towed underwater at speed, when the mass is in a second position (FIG. 1b), in which the center of mass is closer to the center of buoyancy, to improve towing stability in the water, thereby allowing the buoy to be towed with its long axis substantially aligned with the direction of motion, thereby reducing wake/plume in the water.

Abstract: A stowage unit for a payload such as a weapon, countermeasure or unmanned underwater vehicle (UUV), and a method for using the unit to deploy the payload are described. The unit comprises an inner tube for holding the payload, wherein the inner tube is mounted in an outer vessel and so defines a volume between the outer vessel and inner tube. The volume has a first sealing element, which can be used to open or seal the volume at one end, and a valve enabling fluid communication between the volume and inner tube. After deployment of the payload, a weight of fluid equivalent to the deployed payload can be allowed to enter the volume from the inner tube, thus enabling the weight of the unit to remain substantially unaltered from before deployment to after deployment.

Abstract: A stowage unit for a payload such as a weapon, countermeasure or unmanned underwater vehicle (UUV), and a method for using the unit to deploy the payload are described. The unit comprises an inner tube for holding the payload, wherein the inner tube is mounted in an outer vessel and so defines a volume between the outer vessel and inner tube. The volume has a first sealing element, which can be used to open or seal the volume at one end, and a valve enabling fluid communication between the volume and inner tube. After deployment of the payload, a weight of fluid equivalent to the deployed payload can be allowed to enter the volume from the inner tube, thus enabling the weight of the unit to remain substantially unaltered from before deployment to after deployment.

Abstract: A buoy (1) has a main body (5), and a moveable mass (2) positioned inside the main body. The buoy (1) may be tethered to a submarine vessel and used as a communications buoy. The buoy (1) may be configured for floating in a generally upright orientation at the water surface (7) in a position ready for communication, when the mass (2) is in a first position (FIG. 1a) in which the centre of mass is offset from the centre of buoyancy to improve stability in the water. The buoy (1) may be configured for being towed underwater at speed, when the mass (2) is in a second position (FIG. 1b), in which the centre of mass is closer to the centre of buoyancy, to improve towing stability in the water, thereby allowing the buoy (1) to be towed with its long axis substantially aligned with the direction of motion, thereby reducing wake/plume in the water.