Abstract: An energy harvesting system is positionable at an ocean surface to harvest energy from a hydrothermal vent surrounded by cooler ocean water. The system includes an energy storage device positionable proximate to the ocean surface. A cable capable of conducting electrical energy is joined to the energy storage device. An energy harvesting structure is joined to provide electrical energy to the cable. The energy harvesting structure can be positioned proximate to the hydrothermal vent to harvest energy therefrom.

Abstract: A system for three-dimensional tracking of high speed undersea projectiles may utilize a distributed field of randomly positioned passive acoustic sensors. The system measures variables related to the pressure field generated by a supercavitating projectile in flight wherein the amplitude of the pressure generated at a point in space is related to the projectile dimensions, velocity, and trajectory. The system iteratively processes data from the sensors to measure launch velocity, flight direction (trajectory), ballistic coefficient (drag), and/or maximum range.

Abstract: A water entry system increases the drag of an underwater vehicle by disrupting the cavity that forms during high-speed transit of the vehicle through the water. A series of inlet ports are positioned in regions of the vehicle where pressure stagnation occurs during transit. Flow passages connect these inlets to outlet ports at regions of lower pressure. Pressure differences cause jets to flow in the respective passages. The jets produce a high flow rate normal to the original cavity boundary. The jets serve to increase drag in at least two manners. In one case, a flow jet normal to the cavity interface broadens the cavity to increase drag and slow the vehicle. In a second case, a jet can cause waves on the cavity interface to break down the stable cavity. As a result, the vehicle surface is wetted, producing skin friction drag and slowing vehicle.

Abstract: A method for localizing the range and bearing of a distant underwater object includes firing a preselected number of supercavitating projectiles sequentially from a firing location such that each projectile tracks along substantially the same trajectory. Supercavitating pellets are dispersed from a projectile at a pre-selected range. Acoustic signals are sensed to detect acoustic signals caused by supercavitating pellet impact with an object. These signals can be processed to determine the range and bearing to the object. In further steps the range and bearing can be used to aim the projectiles.

Abstract: A method for localizing the range and bearing of a distant underwater object includes firing a preselected number of supercavitating projectiles sequentially from a firing location such that each projectile tracks along substantially the same trajectory. Supercavitating pellets are dispersed from a projectile at a pre-selected range. Acoustic signals are sensed to detect acoustic signals caused by supercavitating pellet impact with an object. These signals can be processed to determine the range and bearing to the object. In further steps the range and bearing can be used to aim the projectiles.

Abstract: An underwater supercavitating projectile includes means to form ripples on its surrounding cavity so as to provide well-defined disturbances of the cavity boundary. As the ripples move aft of the supercavitating projectile and into the wake behind the advancing projectile, the ripples detach to form a pattern of vapor bubbles in the wake that are distinct in both size and regularity from the typical vapor bubbles formed as the cavity collapses behind the advecting projectile. Sensors record the track of the projectile along its path based on the distinct acoustic signature of the vapor bubbles. Combined with the acoustic echo from a target, the relative distance of the projectile to the target can be determined using methods known in the art. Multiple projectile trajectories are used to increase the ability to resolve the target by adjusting the aiming of the projectiles to reduce the relative distance.

Abstract: A high velocity acoustic signal producing underwater shotgun system for dispersing a plurality of relatively small supercavitating projectiles over a wide spatial field at long range using the dynamics of cavity collapse for better target localization in underwater mine clearance. A typical supercavitating projectile design is enhanced to produce a two-staged projectile in order to accomplish this innovation. The first stage of the two stage design allows for the long range firing underwater typical of a supercavitating projectile while the second stage permits the coverage of a wide area with a plurality of small supercavitating projectiles just as the first stage projectile reaches its fixed range. A distinctive feature of the radiated noise from a supercavitating projectile contacting a solid object is used in conjunction with the two stage projectile design to provide a system for underwater mine clearance verification.

Abstract: A system for three-dimensional tracking of high speed undersea projectiles may utilize a distributed field of randomly positioned passive acoustic sensors. The system measures variables related to the pressure field generated by a supercavitating projectile in flight wherein the amplitude of the pressure generated at a point in space is related to the projectile dimensions, velocity, and trajectory. The system iteratively processes data from the sensors to measure launch velocity, flight direction (trajectory), ballistic coefficient (drag), and/or maximum range.

Abstract: A high velocity acoustic signal producing underwater shotgun system for dispersing a plurality of relatively small supercavitating projectiles over a wide spatial field at long range using the dynamics of cavity collapse for better target localization in underwater mine clearance. A typical supercavitating projectile design is enhanced to produce a two-staged projectile in order to accomplish this innovation. The first stage of the two stage design allows for the long range firing underwater typical of a supercavitating projectile while the second stage permits the coverage of a wide area with a plurality of small supercavitating projectiles just as the first stage projectile reaches its fixed range. A distinctive feature of the radiated noise from a supercavitating projectile contacting a solid object is used in conjunction with the two stage projectile design to provide a system for underwater mine clearance verification.

Abstract: A water entry system increases the drag of an underwater vehicle by disrupting the cavity that forms during high-speed transit of the vehicle through the water. A series of inlet ports are positioned in regions of the vehicle where pressure stagnation occurs during transit. Flow passages connect these inlets to outlet ports at regions of lower pressure. Pressure differences cause jets to flow in the respective passages. The jets produce a high flow rate normal to the original cavity boundary. The jets serve to increase drag in at least two manners. In one case, a flow jet normal to the cavity interface broadens the cavity to increase drag and slow the vehicle. In a second case, a jet can cause waves on the cavity interface to break down the stable cavity. As a result, the vehicle surface is wetted, producing skin friction drag and slowing vehicle.

Abstract: A control system for a supercavitating vehicle includes a set of winglets for rapid maneuverability and a segmented ring wing for fine stabilization control. The winglets and ring wing extend from an aft portion of the vehicle. The winglets are supported by a strut attached to the vehicle. The angle of attack of each winglet into the water adjacent the cavity is controlled by a winglet actuator. The winglet assembly may be extended into the water or retracted to be completely within the cavity by means of a spring-loaded actuated mount. The segmented ring wing is controlled by a ring actuator. The ring actuator may be used to control the angle of attack of the ring wing. Alternately, or in combination, the flow over the ring wing may be neutralized by using the cavitator of the vehicle to globally enlarge the cavity and thus limit the flow.

Abstract: A control system for a supercavitating vehicle includes a set of winglets for rapid maneuverability and a segmented ring wing for fine stabilization control. The winglets and ring wing extend from an aft portion of the vehicle. The winglets are supported by a strut attached to the vehicle. The angle of attack of each winglet into the water adjacent the cavity is controlled by a winglet actuator. The winglet assembly may be extended into the water or retracted to be completely within the cavity by means of a spring-loaded actuated mount. The segmented ring wing is controlled by a ring actuator. The ring actuator may be used to control the angle of attack of the ring wing. Alternately, or in combination, the flow over the ring wing may be neutralized by using the cavitator of the vehicle to globally enlarge the cavity and thus limit the flow.

Abstract: A projectile based targeting system for underwater objects includes a trainable gun terminal mounted in a waterproof housing. The gun terminal includes plural gun barrels terminating in waterproof breeches. Noise generating projectiles are launched from the gun barrels, and a fire control system selectively fires the projectiles from each of the plural gun barrels in a noise pattern. A host controller detects and processes noise generated by a launched pattern of the noise generating projectiles to give information about the objects. The projectiles each include a void region connected to an outer surface of the projectile by a hole formed in a neck of the projectile. Launching of the projectile creates a vaporous cavity around the projectile and thus the hole, thereby causing the void region to resonate at a noise generating frequency.

Abstract: A pneumatic launcher has a plenum chamber section, an intermediate chamber section and a launch tube section connected together in a generally linear arrangement. The plenum chamber section defines a plenum chamber that has a closed end and an open end. The intermediate chamber section has aft and forward rupture disks consecutively arranged to define an intermediate chamber. The plenum chamber is pressurized with a pressurized gas to a design plenum pressure and the intermediate chamber is pressurized with a pressurized gas to pressure that is about one-half the design plenum pressure. The intermediate chamber is then depressurizing to produce a pressure imbalance between the plenum and intermediate chambers that causes said aft and forward rupture disks to rupture. As a result, pressure equilibrium occurs between the plenum chamber and launch tube thereby discharging the fluid and projectile from the interior of the launch tube.

Abstract: A system and a method are provided to accurately track the trajectory of high-speed underwater objects. A number of hoops with means for controlling the buoyancy thereof are aligned on a range in the anticipated path of the high speed projectile. The hoops are sufficiently large relative to the size of the projectile and anticipated path. Each hoop contains a number of independent hydrophones. The signals from the hydrophones may be analyzed to accurately determine position and track of an underwater projectile along the plane of each hoop. The system may be used as a fixed range or as a mobile range in a remote location.

Abstract: The apparatus of the present invention utilizes the heat energy of a weapon propulsion system to produce a vapor explosion. It includes an outer shell with a nozzle port and a body being made from a metal. The body surrounds a propulsion device and captures its waste heat to heat metal within the body. An explosive device is embedded in the body and can explode on transmission of a signal whereby the heated metal within the body produces a vapor explosion that significantly enhances the effectiveness and lethality of the weapon. The apparatus also discloses a second metal in the body and a heat shield for further enhancing effectiveness.

Abstract: The apparatus of the present invention utilizes the heat energy of a weapon propulsion system to produce a vapor explosion. It includes an outer shell with a nozzle port and a body being made from a metal. The body surrounds a propulsion device and captures its waste heat to heat metal within the body. An explosive device is embedded in the body and can explode on transmission of a signal whereby the heated metal within the body produces a vapor explosion that significantly enhances the effectiveness and lethality of the weapon. The apparatus also discloses a second metal in the body and a heat shield for further enhancing effectiveness.

Abstract: An assembly for determining speed of a supercavitating underwater vehicle during underwater travel includes a fin mounted on the vehicle aft of a cavitator portion of the vehicle and adapted to be extended outwardly beyond a hull of the vehicle and through a boundary of a gas-filled cavity around the vehicle to form a disturbance in the cavity boundary, which disturbance propagates along the boundary. An acoustic transmitter is mounted on the vehicle and directs acoustic energy toward the boundary and the disturbance. An acoustic receiver is mounted on the vehicle and receives acoustic energy reflected off the disturbance. An autopilot is mounted on the vehicle and clocks times of projection of the fin and acoustic transmission receptions of reflected acoustic energy to determine the speed of the vehicle through the water.

Abstract: A sonar system includes a forward looking array which is embedded in a cavitator for generating a gaseous cavity which minimizes hydrodynamic noise resulting from turbulent pressure fluctuations. A marine vessel incorporating the sonar system includes a hull, a hydrofoil suspended beneath the hull by a strut, and a cavitator for generating a laminar flow over the hydrofoil and for creating a cavity for eliminating turbulent flow contact. The cavitator is located at a leading edge area of the hydrofoil. The sonar array is embedded into the cavitator.

Abstract: The apparatus of the present invention uses waste heat generated by a weapon propulsion system to melt and ultimately superheat metal. Upon termination of the weapon mission, the apparatus explodes thereby causing molten and superheated metal to be instantly introduced to the liquid medium through which the weapon travels. The reaction of the molten and superheated metal with the liquid medium produces a vapor explosion that significantly enhances the effectiveness and lethality of the weapon.