Abstract: A tailcone assembly for an undersea vehicle includes a first tailcone portion having a cavity and a second tailcone portion positionable in and axially extensible from the cavity. An extensible drive shaft is provided for joining the vehicle's engine to a propeller. The extensible drive shaft includes a first drive shaft joined to the engine, and a second drive shaft rotating with the first drive shaft. The second drive shaft is supported by the second tailcone portion and is axially extensible from the first drive shaft upon deployment of the second portion. The propeller is positioned on the second drive shaft outside the second portion. A biasing means is provided between the tailcone portions for deploying the second portion.

Abstract: A supercavitating projectile is disclosed and includes a combustion chamber, a forward-directed jet nozzle and a comparatively larger gas duct/rear-directed jet nozzle. The combustion chamber is filled with a propellant having a hollowed core. The core serves as a pathway to fluidly allow combustion gases to the jet nozzles. In operation, the propellant combusts to form gasses forced forward through the forward-directed nozzle to generate a virtual cavitator in the form of a ventilation gas bubble. Combusted gasses are also forced out the rear-directed nozzle forming a propulsion jet. The projectile therefore uses the rear-directed jet to maintain a cruise velocity approximate to the launch velocity and employs a source of ventilation gas using the forward-directed jet for supercavitating of the projectile.

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 present invention is a dispenser mounted on the aft section of a torpedo for deploying an elongated, flexible article along a deployment axis. There is a molded elastomeric encasement over the exterior perimeter of the outer weldment of the dispenser for providing shock, impact, and force protection to the dispenser. A metal stiffener plate is secured to the top portion of the encasement for distributing localized compressive loads on weak sections of the dispenser. The encasement together with the stiffener plate enlarges the dispenser to approximately the same outer diameter as the torpedo to which it is attached. The encasement incorporates a fore and aft groove at a lower position with small notches for positioning and anchoring a torpedo power cable. The encasement further incorporates a pivoting retention door assembly for restraining the torpedo power cable within the groove in the encasement.

Abstract: An assembly for vehicle deceleration and buoyancy comprises a pair of doors enclosing flotation bags inflatable for buoyant recovery of the torpedo. In operation, the doors are controllably forced open to an initial angle off a longitudinal axis of the assembly to a fully-deployed position by hydrodynamic forces of the movement of the vehicle. From the doors blocking the hydrodynamic forces, the vehicle decelerates. The hydrodynamic braking action of the doors reduces the time required to reach terminal velocity, thus reducing the depth the vehicle sinks and enabling recovery with less gas required for inflation.

Abstract: An undersea vehicle having both low emitted noise and low reflectivity is provided. The undersea vehicle has a hollow cylindrical hull with all components, sensors, electronics, motors, and other internal components with the exception of the propellers, located within the shell of the cylindrical hull. The hollow center of the hull provides a duct and propeller configuration with the shaping of the inlet tube designed to reduce forward noise transmissions, such as reflected active sonar signals and emitted noise. The internal duct gradually constricts to a throat section and thereafter diverges to an output section where dual counter-rotating propellers are located. The result is that most of the internal turbulent flow and the propeller noise is located behind the throat and is thereby reflected in the aft direction. Steering of the vehicle is accomplished by canting the leading edge intake section and the duct exhaust section.

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.

Abstract: A tailcone assembly for a submarine countermeasure includes a generally hemispherically shaped shell having a planar aft end and an annular open forward end. Fins are fixed to the shell equidistantly around the shell externally thereof, each of the fins having a planar outboard surface extending aft and inboard of the shell. Connector structure is on the forward end of the shell for connecting to an aft end of the countermeasure. A first aperture is disposed in a side of the shell and a cable extends from inside the shell therethrough. A second aperture extends through one of the fins and the cable extends therethrough. An opening is disposed centrally of the shell aft end, extends therethrough, and is adapted to retain a shaft assembly therein.

Abstract: A system and method is disclosed for a countermeasure threat emulator. The countermeasure threat emulator is provided in a tubular housing that may be launched from a submarine or ship. The electronics of the countermeasure threat emulator include a CPU board for running software, communicating with a computer external to the tubular housing, and data recording. The computer external to the tubular housing preferably incorporates a database that includes data representative of a plurality of foreign countermeasures as well as domestic countermeasures. The data may be downloaded to the CPU board as well as updated for reprogramming of the CPU board. A digital signal processing board preferably utilizes a plurality of DSP processors for running the main software that is capable of producing a wide range of acoustic signal outputs.

Abstract: A high-speed supercavitating underwater vehicle includes an elongated hull of circular cross section, the hull having a cavitator at a forward end thereof and means for ventilating gas to form a cavity around the hull in underwater travel. An expandable annular skirt is fixed on the hull and is provided with an outer surface proximate an outer surface of the hull. The skirt is expandable to increase a diameter of the skirt from proximate a diameter of the hull to proximate a diameter of the cavity to define an annular gas film between the expanded skirt and a boundary of the cavity. The expanded skirt acts to substantially reduce the flow of gas from a forward high pressure zone of gas to an after low pressure zone of gas.

Abstract: For reducing the number of acoustic transducers required by a torpedo sonar for target searching, the transducers are arranged in four particular zones at the curved contour of the torpedo bow forming a conformal sonar array. The circular first zone covers the vertex region of the torpedo bow and is surrounded by a ring-shaped second zone. Extending from the second zone on both sides of the torpedo are third lateral transition zones, which change over into fourth lateral zones of constant width ending at the great circle of the hemispherical or paraboloid-shaped torpedo head.

Abstract: The present invention permits determination of steady-state off-design performance characteristics of a vehicle, such as a torpedo, powered by a closed cycle thermal propulsion system. The method may be utilized to determine propellant consumption for a torpedo resulting from various off-design kinematic maneuvers. Total run time may be calculated in response to a plurality of torpedo speed changes and/or torpedo configurations of variable torpedo length or torpedo diameter. The present invention may be utilized to define weapon design options for existing or future underwater weapons with mission requirements different from those for which the weapons were originally designed.

Abstract: An apparatus for joining cylindrical sections, including a semi-cylindrical profile section or member adapted to be coupled to a cylindrical section on an outer circumferential portion of the profile section or member and including an outer circumferential groove and an inner circumferential ridge; a ring-shaped compression ring or member coupled to the profile section or member and including a circumferential groove on an outer portion thereof and attachment fixtures or members on opposite sides thereof; and a pair of semi-cylindrical tension bands or members forming a ring shape and each including a pair of inner circumferential ridges and attachment fixtures or members on end portions thereof. The circumferential ridge of the profile section or member couples to the circumferential groove of the compression ring or member. One of the circumferential ridges of one of the tension bands or members couples to respective of the circumferential groove of the profile section or member.

Abstract: A method is provided to process system test data to determine certification parameters of the system based on the test data. For a torpedo launch system, the velocity data is generated by a Pressure/Velocity/Displacement housing interfaced with a computer based data acquisition system and known launch system and test parameters, such as sample rate, muzzle exit length, time of acquisition, decimation factor and low pass cutoff frequency are provided as inputs. The method forces assigns a value of zero to any data less than a predetermined threshold in order to eliminate non-zero levels contributed by ambient noise. The method then passes the data through a filter chosen to agree with hand fit smoothing methods, so as to obtain a smoothed velocity profile. The smoothed data is processed to obtain and display an acceleration profile and a displacement profile, as well as data points for peak acceleration, time at peak, acceleration pulse width, muzzle exit velocity and time at exit.

Abstract: A submarine countermeasure vehicle includes an elongated body for supporting a countermeasure device, and a propulsion assembly mounted on an after end of the body. The propulsion assembly includes a rotatable propeller hub, propeller blades mounted on the hub and moveable between a first position wherein the blades extend substantially radially outwardly from the hub, and a second position wherein the blades extend generally axially of the hub. A spring is mounted on each of the blades and in the hub, the spring biasing the blades toward the first position, but of sufficient flexibility to permit the blades to move to the second position upon launch of the vehicle from an underwater launch tube.

Abstract: A flexible nose assembly for an underwater vehicle provides increased energy-absorbing capabilities and facilitates recovery and handling of the vehicle. The flexible nose assembly includes a flexible nose cap, at least one retrieval device, and at least one cable that is strong in tension, yet weak in compression which is coupled between the retrieval device and the UUV body. The flexible nose cap has a gap formed therein allowing the communication of environmental water into the region between the vehicle body and the nose cap. Optionally, the retrieval device may be recessed into the flexible nose assembly, thereby reducing hydrodynamic drag and overall vehicle length. Energy-absorbing ballast can be positioned within the nose cap in order to further enhance survivability.

Abstract: A system and method is provided to replenish a submarine's tactical capabilities, e.g., weapons, sensors and communications, while the submarine remains within a hostile environment. One or more Underwater Combat Vehicles (UCV's) are pre-positioned at strategic locations or are launched from a surface and/or airborne platform. The UCV's include full tactical capabilities, which can attach to and be integrated with a submarine's capabilities. To initiate replenishment, a submarine broadcasts a signal, or dispatches one of the UCV's under its direct control, to make contact with one of the pre-positioned UCV's or with a central command platform. The pre-positioned UCV's are programmed to search for and locate the submarine. This can either be accomplished using signals broadcast from the submarine, or using UCV internal navigation systems and a last known position for the submarine.

Abstract: A torpedo mounted dispenser for a coil of flex hose and control wire includes a rigid shell round in widthwise cross section, and a circular shock mount disposed centrally of the shell, the shell and the shock mount defining an annular chamber therebetween. Hooks are mounted on an exterior wall of the shell. Slots are defined by the shell, each slot being proximate one of the hooks. A retainer ring is disposed in the chamber. Retainer loops each extend at least partly around the retainer ring, through one of the slots, and is attached to one of the hooks. The coil of flex hose and control wire is disposed in the chamber and is movable lengthwise through the retainer ring while uncoiling and paying out from the dispenser.

Abstract: A deployable nose is used on an underwater vehicle to provide a shorter length when in a retracted position and to provide a reduced drag when in the deployed position. The deployable nose includes a plurality of nose sections and a deployment mechanism that moves the plurality of nose sections from the retracted position to the deployed position. The nose sections include a base nose section attached at the end of the underwater vehicle, an outer nose section having a rounded contour, and one or more intermediate nose sections between the base nose section and outer nose section. In the retracted position, the outer nose section and one or more intermediate nose sections are retracted generally within the base nose section. In the deployed position, the outer nose section and intermediate nose sections extend outwardly from the base nose section and interlock proximate the edges of the nose sections to form the deployed nose.

Abstract: A launch platform for a host vehicle. There is a cradle having a cylindrical shape with peripheral axial recesses formed therein and arranged around the cradle. A release mechanism is positioned within the cradle. The release mechanism releasably joins small cylindrical undersea vehicles positioned in said peripheral axial recesses.

Abstract: An apparatus for joining cylindrical sections, including a semi-cylindrical profile member adapted to be coupled to a cylindrical section on an outer circumferential portion of the profile member and including an outer circumferential groove and an inner circumferential ridge; a ring-shaped compression member coupled to the profile member and including a circumferential groove on an outer portion thereof and attachment members on opposite sides thereof; and a pair of semi-cylindrical tension members forming a ring shape and each including a pair of inner circumferential ridges and attachment members on end portions thereof. The circumferential ridge of the profile member couples to the circumferential groove of the compression member. One of the circumferential ridges of one of the tension members couples to respective of the circumferential groove of the profile member. The attachment members of the tension members couple to respective of the attachment members of the compression member.

Abstract: A method for the automated generation of ballistic constants for use in a trajectory control system. The potential trajectory of a pursuing vehicle is divided into a plurality of multiple sequential phases wherein each phase is characterized by a plurality of ballistic parameters. Known simulated data from a number of runs concerning the pursuing vehicle is analyzed. Ballistic parameter values for each run are obtained and statistically analyzed to produce generic constants for a particular set of operating conditions. Resulting matrices are stored as part of a two-dimensional, kinematic vehicle model to facilitate the propagation of projected trajectories during firing control solutions.

Abstract: Three extender assemblies are mounted on the torpedo-mounted dispenser (TMD) of a torpedo to provide shock hardening of the TMD. In a first embodiment, the extender assemblies consist of short sections of metal tubes mounted on inner plate portions. The inner plate portions are bent to conform to the TMD radius and attach to the TMD such that the metal tubes are aligned longitudinally on the TMD. Outer plates are attached to the tubes and are in contact with the dolly used to support the torpedo and TMD. When the dolly the TMD is subjected to a shock load, the tubes deform to take up shock loads applied to the TMD through the dolly. To attach the assemblies to the TMD, slots on each inner plate are positioned over hooks on the outside surface of the TMD. The hooks are part of the TMD assembly and serve to secure o-ring or spring retainers for the cable within the TMD. An eye bolt fits over the hook and is bolted to a bent tab on the inner plate.

Abstract: A marine propulsion assembly comprises a drive shaft, a first propeller fixed to the drive shaft and turnable therewith in a first direction, an annular array of gear teeth disposed on the first propeller and turnable therewith, a second propeller aligned with the first propeller, and an annular array of gear teeth disposed on the second propeller. Bevel gears are disposed between the first and second propellers and engaged with the first and second annular arrays of gear teeth. The bevel gears transmit rotation of the first propeller to the second propeller, such that the second propeller turns in an opposite direction relative to the first propeller.

Abstract: A supercavitating water-entry projectile having empennage on the aft end which provides both aerodynamic and hydrodynamic stability and a supercavitating nose section is provided. A representative projectile is a subcaliber munition adapted for use in a 25 mm weapon using a sabot currently in use with the M919 round. The projectile has circumferential grooves around its center section to match these sabots. A key feature in the invention is the size and shape of the nose section. The projectile has a novel high strength extended blunt nose section followed by a truncated conical section which angles towards the body of the projectile in the range of five degrees. During underwater trajectory, the entire projectile is contained within the cavitation bubble formed by the blunt nose tip. The projectile's aft empennage, which provides both aerodynamic and hydrodynamic stability, fits within the bore of the weapon.