Abstract: A robotic fish comprises one or more torque reaction engines and a fish body, wherein the torque reaction engine cyclically oscillates and causes a wave to propagate across the fish body, including through a flexible wing, accelerating thrust fluid and propelling the robotic fish.

Abstract: A watercraft comprises a motor, an inertial mass, and a fin. The motor oscillates the inertial mass about an axis, producing a torque reaction on and oscillation of the motor. Oscillation of the motor is communicated to the fin, producing thrust. A fluke, fin, or wing comprises an angle of attack mechanism, wherein the angle of attack mechanism may use power from the fluke, fin, or wing to adjust an angle of attack of the fluke, fin, or wing relative to a surrounding thrust fluid.

Abstract: A water submersible vehicle, the vehicle has a variable buoyancy system where flight of the submersible is controlled by a forward thruster forward of the center of displacement and that regulates both pitch and up-and-down hover. The vehicle in combination with a control system allows the user using to use only two control elements, one with each hand, to fly the vehicle by controlling motion along long axis, yaw, pitch and roll. An ergonomic submersible pod may be incorporated into the water submersible vehicle. The ergonomic submersible pod may also be used with other flight systems to provide for new types of low cost underwater travel.

Abstract: Disclosed are systems, devices, and methods for swimming using a swimming apparatus that includes an exterior shell, optionally including a top half and bottom half and an opening to accommodate a propulsion system.

Abstract: An underwater vehicle includes a longitudinal body that defines a longitudinal axis and is rotatable about the longitudinal axis between a forward orientation and a sideways orientation, a wing attached to the longitudinal body that is moveable between a vertically extending wing orientation when the longitudinal body is in the forward orientation and a horizontally extending wing orientation when the longitudinal body is in the sideways orientation, a propulsion system having a front propulsion device and a rear propulsion device that is arranged rearwardly along the longitudinal axis relative to the front propulsion device, and an after-propulsion system arranged at a rear end of the longitudinal body that provides thrust along the longitudinal axis. The secondary propulsion system provides thrust in a perpendicular direction relative to the longitudinal axis.

Abstract: A hybrid energy harvesting system for powering underwater vehicles having at least one thermal engine, at least one of a solar or a wave energy harvester, and a battery which stores electric energy produced by the harvesters. The energy harvesters keep the battery charged and thereby expand an underwater vehicle's operational areas to high latitudes and shallow water. Multiple thermal engines employing different phase-change materials can be used to expand the vehicle's working temperature range and thus allow it to operate over a larger area. An electric motor powered by the battery and a pump driven by the motor can be used to pump hydraulic fluid between the accumulators and external bladders of the thermal engines to cause the vehicle to descend and ascend when the thermal gradient to which the vehicle is subjected is insufficient.

Abstract: A method for deploying a payload into a body of water using a deployment vessel, the deployment vessel including a hull defining a payload compartment, the method including positioning the payload in the payload compartment of the deployment vessel, the deployment vessel and the payload having a buoyancy, wherein the buoyancy is initially negative, deploying the deployment vessel into the water at a drop zone, wherein the deployment vessel moves horizontally through the water as it submerges vertically downward under a force of gravity, changing the buoyancy to positive after a minimum horizontal distance is established between the drop zone and the deployment vessel, thereby causing the deployment vessel to surface and, after the surfacing of the deployment vessel, opening the hull to release the payload therefrom.

Abstract: An autonomous underwater vehicle (AUV) is disclosed for transporting and delivering a positively buoyant payload and/or a negatively buoyant payload to a destination. The AUV can be gravitationally propelled through the sea. The AUV can comprise a flexible vehicle body that receives a positively buoyant payload (e.g., incompressible fluid, like fuel) and can comprise a negative buoyancy component (e.g., elongated spine, electronics, cargo, etc.). A weight of the negative buoyancy component is correlated to a volume of the positively buoyant payload whereby the AUV is substantially neutrally buoyant at sea. The positively buoyant payload can be hydrostatically pressurized to hydrodynamically shape the body. The vehicle body can be collapsible for storage. The AUV can collect underwater intelligence data and transmit said data when surfacing. The AUV can loiter at sea for long periods of time. Associated system and methods are disclosed for transporting a positively buoyant payload with an AUV.

Abstract: An underwater vehicle may be configured to perform vertical profiling and diagonal profiling. The vehicle may include a body having an elongated shape with a central longitudinal axis orthogonal to a central lateral axis. The vehicle may include lateral control surfaces. The lateral control surfaces may be disposed outside of the body and mechanically coupled with the body at a position proximal to the central lateral axis. The lateral control surfaces may be configured to rotate about a control axis parallel to the central lateral axis in order to control an attitude of the vehicle during ascent or descent. A given one of the lateral control surfaces may have a portion extend from the mechanical coupling in a direction perpendicular to the control axis.

Abstract: Embodiments described herein provide a highly reliable UUV recovery systems and methods that utilize multiple independent release mechanisms that can detach a load and allow the UUV to float to the surface of the water. One embodiment is a recovery system for a UUV. The recovery system includes a detachable load that renders the UUV neutrally buoyant in water. The recovery system further includes a plurality of release mechanisms that detach the load to render the UUV positively buoyant in the water. The release mechanisms include a first, second, and third release mechanism. The first release mechanism detaches the load in response to a command signal. The second release mechanism detaches the load in response to the UUV being submerged in the water beyond a threshold time. The third release mechanism detaches the load in response to the UUV exceeding a maximum depth in the water.

Abstract: A vessel for transporting a payload through water having a body which travels below the surface of the water and carries the payload, fins extending laterally from the body below the surface of the water a telescoping tower which extends above the surface of the water from the body, a wing extending laterally above the water from an upper portion of the tower, engines mounted on the wing for propelling the body through the water, and propellers mounted on the under sides of the fins for lifting the vessel and holding the vessel in a raised position with the body at the surface of the water while loading and unloading the payload.

Abstract: A watercraft having a plurality of flexible section secured to a mount, having a drive assembly, wherein the water craft can move the flexible section upwardly and downwardly to propel the watercraft through the water.

Abstract: A submarine (1) includes a bridge (4), a bridge fin (3) and a device (8) for releasing and recovering a secondary self-propelled underwater vehicle (90). The device (8) includes a handling element (8A) which can be used to move the secondary underwater vehicle between a storage zone (18) and a release or recovery zone (19) and a reversible grip element (14) solidly connected to the handling element (8A), which can be used to free the secondary underwater vehicle (90) at the moment of release and to attach the vehicle at the moment of recovery. The release and recovery device (8) is designed such that the release and recovery zone is located outside the turbulent zone (7) that surrounds the moving submarine.

Abstract: Compliant mechanisms whose dominant modes of vibration match the desired kinematics for locomotion in a given environment are used to mimic motions of a living animal. Mechanisms are simple and mechanically robust. They may have as few as one actuator, which excites the compliant portion to vibrate in a natural mode that results in motion that mimics a living animal. Additional actuators may drive directional elements such as flippers. Models for compliant mechanism bodies were derived and used to identify actuator, material, and geometrical properties of the required mechanisms. The design and fabrication techniques of mechanisms implementing these ideas is also presented. Experiments found that important features of fish-swimming kinematics can be captured qualitatively by compliant mechanisms. The resulting mechanism swimming performance was ? of the real fish performance, comparable to current robotic fish.

Abstract: A buoyancy system includes a chamber having a volume associated therewith, and bladders within the volume of the chamber. Each bladder contains a clathrate mixture in a liquid state. The chamber includes an opening to allow surrounding water to circulate within the volume and contact the bladders. As the chamber is submerged in the surrounding water, the bladders expand based on the clathrate mixture changing from the liquid state to a solid state. This changes buoyancy by allowing less water to circulate within the volume of the chamber.

Abstract: An underwater vehicle is provided with facility for affixing to and maintaining station on a hull of another marine vehicle. The underwater vehicle includes a hull with a propulsion means for movement underwater. Maneuvering planes are mounted on the hull. Body panels are movably fixed to the hull and are moveable from first positions in which the panels conform to a shape of the hull to second positions in which the panels extend outwardly from the hull and toward the other marine vehicle, free edges of the panels being engageable with the other marine vehicle to deter flow of water between the underwater vehicle hull and the other marine vehicle and guide flow of water around the underwater vehicle hull to pin the underwater vehicle against the other marine vehicle hull.

Abstract: A submarine vehicle able to control the navigation of a towed submerged object (3). The vehicle includes a body (5) equipped with stabilizing fins (7a, 7b, 7c), at least one of which (7c) is free to rotate and is ballasted, or linked to a ballast, for roll stabilization and/or orientation of the vehicle when it is in motion.

Abstract: A submarine is comprised of a hull with an external seat on top and a backrest behind the seat. A control column and a grab handle are positioned in front of the seat. External drive motors attached to the hull drive propellers housed in protective cages. Servo driven dive planes and stern rudders provide directional control. Batteries are attached to a mounting plate positioned in channels inside the hull. The control column, drive motors, dive planes, rudders, and batteries are connected to a controller. A detachable safety key tethered to the rider is arranged to disable the drive motors and control column if the rider falls off and pulls the key from the hull. A water sensor on top of the backrest is arranged to prevent the diving planes from pitching down when the sensor detects water for limiting diving depth.

Abstract: A bottom activated retractable control device includes a fin member having a front edge, a trailing edge opposite to the front edge, a bottom edge between the front edge and the trailing edge, and an arm portion extending from and coextensive with the leading edge and away from the bottom edge. The arm portion includes a pivot pin extending in a perpendicular direction from each side of the arm portion. A pivot housing having an aperture is provided for receiving the pivot pin of the arm portion, the housing enabling both a vertical pivot of the fin member upon contact of the fin with, an object and axial rotation of the fin about the arm portion of the fin member. A well is formed in the bottom surface of an underwater vehicle corresponds in depth to a fully retracted position of the fin member and in width to any rotated position of the fin member.

Abstract: A device for controlling the position of an underwater cable comprises a body, first and second actuators, and a pair of wings. The body is stationarily mountable to the underwater cable and the first and second actuators are disposed in the body. Each wing has an axis of rotation and the wings are coupled to the first and second actuators to control the depth and the horizontal position of the underwater cable in the water.

Abstract: A mechanical actuating device for moving an aerodynamic or hydrodynamic surface includes plural flexure members confined in an elastically deformed condition. The flexure members are movable against the force generated by their elastic deformation to move the device into one of at least three stable positions, in which the device, and therefore the aerodynamic or hydrodynamic surface, are held by the force generated by elastic deformation of the flexure members. Since the flexure members are always elastically deformed, the device “snaps” between discrete, stable positions and is held firmly in each. In another embodiment more flexure members can be used to provide additional stable positions. In one application, the actuating device is used as a trailing edge tab for a helicopter or tiltrotor blade to reduce 1/rev vibrations. The device can be actuated manually or electrically using shape-memory alloy wires to snap the flexure members into their various stable positions.

Abstract: A submersible water toy comprises a buoyant streamlined body and a pair of wings attached thereto. While the body encourages the vehicle to rise in water, the wings, being formed from thin flat members resist vertical movement while providing little resistance to forward motion. The centerline of the wings is positioned behind the center of gravity of the bode so that the vehicle will rise in a forward direction while the wings resist vertical movement. Upon release, the submerged water toy will glide at relatively high speeds in a forward direction while slowly rising to the surface.

Abstract: A hydrofoil stabilizer fixed to an underwater hull and provided with a pair of pivotally deflectable control flaps through which surface lift on the stabilizer is controlled, is provided with trailing edge tabs on both of the flaps that are pivotally deflected in the same direction to further offset and thereby improve recovery from surface jam inducing lift force on the stabilizer which adversely affects maneuvering control.

Abstract: A mechanical actuating device for moving an aerodynamic or hydrodynamic surface includes at least one flexure member confined in an elastically deformed condition. The flexure member is movable against the force generated by its elastic deformation to move the device into one of a plurality of stable positions, in which the device, and therefore the aerodynamic or hydrodynamic surface, are held by the force generated by elastic deformation of the flexure member. Since the flexure member is always elastically deformed, it “snaps” between discrete, stable positions and is held firmly in each. In another embodiment more flexure members can be used to provide additional stable positions. In one application, the actuating device is used as a trailing edge tab for a helicopter or tiltrotor blade to reduce 1/rev vibrations. The device can be actuated manually or electrically using shape-memory alloy wires to snap the flexure members into their various stable positions.

Abstract: A pelagic free swimming aquatic vehicle includes a rigid forebody having a predetermined volume; a watertight chamber in the forebody; and a flexible afterbody having a lesser volume than the forebody and including a maneuvering and propulsion propulsion structure and a drive system for driving the structure with a traveling sinusoidal wave motion.

Abstract: A debris deflector protects an underwater vehicle's control. surface while ntroducing little or no flow disturbance around the control surface. The deflector extends outward from the vehicle to peninsulate the control surface. The deflector's cross-section is defined by a wedge shape subtended by an arc with the apex of the wedge shape always pointing towards the control surface.

Abstract: A depth control apparatus for seismic streamers, comprising a central unit adapted for inserted mounting in the streamer substantially in axial alignment with the streamer, a housing which can rotate about the central unit and carries at least one control wing being angularly adjustable about a transverse axis adapted to be substantially horizontal in operative position, and an electric motor for adjusting the angle of the control wing about the transverse axis. The motor is located in the central unit and is adapted to have its current supply through the streamer. The control wing is so arranged on the housing that the transverse axis in operative position runs underneath the central unit. A transmission mechanism for the angular adjustment of the control wing by means of the motor, comprises a slide member which can be moved in the axial direction of the central unit and preferably surrounds the central unit.

Abstract: A fin assembly for an underwater vehicle, the assembly comprising a portion f the hull of the vehicle having a recess therein, and a sleeve proximate a forward end of the recess and inclined inwardly from the hull portion at an angle to the hull portion and inclined transversely of the fore-and-aft axis of the vehicle at an angle to the hull portion. The assembly further comprises a fin having a mounting post at a base end thereof, the post being at an angle to the lengthwise axis of the fin, and at an angle to a fore-and-aft axis of the fin. The post is disposed in the sleeve and turnable therein to move the fin from a first position in the hull recess wherein the fin is disposed generally axially of the vehicle and conformed to the hull portion, to a second position in which the fin extends outwardly from the hull in a position radial to the vehicle axis and inclined rearwardly at an angle from a line extending radially of the vehicle axis.

Abstract: A control surface for a vehicle comprising a flexible elastomeric body with ts base joined to the vehicle to form a smooth surface, a rigid tip bar joined to the distal end of the body, and a control member for turning the rigid tip bar to bend the elastomeric body and generate lift. The control member can be a shaft which extends from the interior of the vehicle to said rigid tip bar to allow said shaft to rotate said tip bar.

Abstract: A retractable bow diving plane is provided which can be rotated when fully xtended or retracted or when at any position in between, and which allows for independent operation of the port and starboard bow diving planes. The major assemblies for each plane are a large rotor bearing, four rotational hydraulic cylinders, and an extension and retraction hydraulic cylinder assembly. The plane is engaged in a slot in the middle of the rotor bearing. This rotor bearing supports the plane, rotates the plane, and allows the plane to move through the slot for extension and retraction.

Abstract: A submersible boat is provided which utilizes a planing boat hull with a sharp bow and blunt stern. The submersible boat performs as a planing boat until it nears the target location. Then, the boat submerges in order to avoid detection. After this vessel submerges, it travels with the blunt end forward and the sharp end aft.

Abstract: A water vessel comprising a hull, at least one retractable hydrofoil apparatus configured for disposition in an extended orientation for vessel operation in a hydrofoil mode and for disposition in a retracted orientation for vessel operation in an undersea mode and propulsion apparatus providing propulsion of the vessel in both the undersea mode and the hydrofoil mode.

Abstract: A watercraft having positive static buoyancy is provided which is operable both as a hydrofoil and submersible vessel. It is generally shaped in the form of a dolphin or porpoise, with the equivalent of fins acting as both navigation and attitude control mechanisms. Pectoral or forward fins provide hydrofoil struts when manipulated into one position and then are operable as diving planes when displaced into an alternate position. A dorsal fin provides supplemental rudder control. A pair of flukes or rear fins provide for pitch and/or dive control while the vessel operates in the submerged mode. These fins and a propulsion system are either manually or computer controlled by way of hand held joysticks and foot rudders. Submerged operation is achieved with an internal combustion motor by including an air compressor and air storage tank(s) with an air intake arrangement having automatically operable devices serving to open and close an air intake in response to exposure to water.

Abstract: An attitude adjusting apparatus for use by scuba divers automatically varies the position of ballast relative to the center of buoyancy as the attitude of their body underwater changes. An elongate hollow weight tube enclosed at one end has a removable closure at the opposite end and contains a quantity of small metal balls or shot. The weight tube is carried in close proximity to the torso of the diver in a position with its longitudinal axis generally parallel to the longitudinal axis of the torso of the diver. The free-moving balls or shot are movably disposed within the interior of the weight tube and are movably distributed at varying locations within the weight tube between a forward lowermost position as the diver assumes a descending head-down position and a rearward lowermost position as the diver assumes an ascending head-up position, and will be distributed along the length of the weight tube as the diver assumes a horizontal position.

Abstract: A submergible, two-passenger dive sled includes a foldable sled frame being adjustable in length, a break-away tow hook for interconnection within the tow line of a power boat, an adjustably foldable deflecting screen having a preferred position for maintaining the elevation of the sled at a preferred depth, forward most situated diver-controlled pivotable ailerons for adjusting and manipulating the axial stability and selected depth of the sled, and a break away tail piece feature for added safety. The dive sled is structured to have a positive bouyancy at its front end relative to its back end. The sled may be segmented into interconnected parts and may include selectively removable components for convenient storage and shipment. A number of electric lines are provided for provided power to lights optionally mounted on the sled and for allowing communication by an electric signal switch and an optional voice communicator. A series of diver-enclosing anti-shark shields may optionally be provided.

Abstract: A fluidfoil (78) for use in guiding fluid-borne vehicles has first and second bodies (82, 80) arranged in telescoping relation and collectively defining the leading and trailing edges (18, 20) of the fluidfoil so that the chord length (24) of the fluidfoil is variable. The bodies (82, 80) are rotatable about a shaft (16) defining an axis (14) in fixed positional relation to the leading edge (18), and the fluidfoil (78) is operable under the influence of a relatively moving, surrounding fluid medium (22) to assume an angle of attack which depends on chord length (24).

Abstract: A submarine is provided with a large number of individual fins, some of which are arranged to create a "slot" effect between them. The fins are controlled in a way which is dependent on which of them may be in service at a particular time so that manoeuvreability is substantially unaffected by damage to a limited number of them.

Abstract: A submarine hull which has a half wing-like sail which projects vertically upwards, is provided with a keel-wing that also is half wing-like, but projects vertically downwards. By preference the keel-wing has a lower end plate and its main portion is trailed by two slotted flaps which can be pivotally moved in both directions about respective vertical axes in coordination with movement of the rudder of the submarine. If needed for permitting operation in shallow water or with the hull close to the bottom, the wing can be made to retract. The keel-wing not only counters the sail's rolling movement and keeps the hull upright, but also adds a side force to assist in tightening the turn.

Abstract: A two-level sea-land creeping vehicle formed by three main parts: a frustoconical bow portion which is movable independently but connected to the central part or compartment in the form of a drop of water, which is flat in the lower part and which is fixed with respect to the rear part which comprises the drive and steering assembly, as well as the breathing and safety zone.The vehicle is displaced on land by means of two rollers disposed in the lower region and by the drive of the motor, and it is likewise displaced on the surface of water due to its buoyancy and it is also displaced in a condition of dynamic immersion by the drive of the motor linked to positioning of the bow portion and hydroplanes; the air required is picked up from the surface by means of an appropriate telescopic arrangement and it has the particularity of not being hermetically sealed in the immersed condition. It is totally safe since it rises automatically to the surface when the motor stops.

Abstract: A control surface design for submerged vehicles. The control surfaces are vably mounted or radially extending support members such that the wake created by the deflection of the control surfaces will not be transmitted to the propeller. The support members have a cross section that minimizes flow disturbances in the region of the propeller.

Abstract: In a sonar buoy suspended from a helicopter, the lower stabilizing ring of a buoy of this type is replaced by a set of fins which get folded against the body of the buoy during its descent into the water and get unfolded when they are raised again to form a stabilizing crown around the bottom of this body, thus enabling a buoy of this type to be stabilized both during descent and when being raised again.

Abstract: A semisubmersible water surface navigation ship with even draft comprising at least two lower hulls, which can be submerged under water to reduce resistance and have a shape affording low friction resistance, and which are equipped with lifting and diving planes, at the bow and stern parts, and an upper hull above the water surface being connected to the lower hulls by way of water breakers. In order to keep an even draft or trim during navigation, the lifting/diving force capacity of the lifting and diving planes is designed to be greater than the buoyancy change of the water breakers owing to loads such as waves and wind. Steering rudders, propellers and water ballast tanks are installed in order to cause the ship to navigate or lie to under any one of a shallow draft state, a semisubmerged state and a deep submerged state. The upper hull is provided with superstructures with sufficient reserve buoyancy for maintaining the stability of the ship under the deep submerged state.

Abstract: A remotely operated submersible vehicle (21), wherein the vehicle includes flotation cells (62) to provide positive buoyancy, and the vehicle is connected to a disposable clump weight (22) of sufficient weight to overcome the positive buoyancy. The connection between the clump weight and the vehicle is by way of a cable (25) which can be wound onto and off from a drum winch (45) within the vehicle to control its height off the seabed (23). The trim of the vehicle is maintained by adjusting the horizontal position of a cable guide (43) through which the clump weight cable (22) passes, the cable guide (43) being moved longitudinally and transversed by hydraulic cylinders (47). Control signals to control and monitor the operation vehicle are provided via an umbilical cable (29) extending from a ship (76) or platform on the surface.

Abstract: A submersible positioning device, such as a paravane coupled to a distant end of a towing cable may include a front cylindrical stabilizer having a wing diametrically disposed therein and having a predetermined angle of attack coupled to a towing bridle which in turn is coupled to the towing cable. A rear stabilizer may be coupled to the front stabilizer by a shaft, extending from the lower surface of the wing, and a plurality of struts coupled to the perimeter of the front stabilizer. A buoy coupled to the uppermost point of the front stabilizer may be pulled underwater while under tow, but returns the paravane to the surface for recovery purposes while not under a tow.

Abstract: An elongated streamlined hull is provided having front and rear ends and a first pair of rear opposite side horizontally outwardly projecting main foils are supported from the hull and have their centers of plan area disposed aft of amidships of the hull. A second pair of forward foils of considerably smaller plan area are mounted from opposite side forward portions of the hull spaced considerably forward of amidships for controlled angular displacement relative to the hull about generally horizontal axes extending transversely of the hull. First control structure is provided for simultaneously adjustably angularly displacing the forward foils and the hull includes front and rear buoyancy tanks, a compressed gas storage tank disposed centrally intermediate the buoyancy tanks and second control structure operatively associated with the storage and buoyancy tanks to selectively flood and blow the buoyancy tanks with ambient water and compressed gas from the storage tank.

Abstract: According to the present invention there is provided apparatus for controlling the hydroplanes of a marine vessel comprising a pair of hydroplane-carrying crossheads mounted for movement towards and away from each other to effect retraction and extension of the hydroplanes into and out of the vessel, first hydraulic cylinders for effecting the retraction and extension movement of the crossheads, characterized in that there is provided second hydraulic cylinders independently and operatively associated with each of the crossheads for effecting tilting of each hydroplane about an axis thereof, and synchronizing gear associated with the second hydraulic cylinders for ensuring that tilting of each hydroplane is effected substantially in snychronism.

Abstract: A highly maneuverable water sled device is disclosed which includes a joystick for controlling a rudder and an elevator. The base of the water sled device is provided with upwardly extending, hollow side, front and rear walls which are individually fillable with water to vary the buoyancy of the device. A preferred embodiment of this invention further includes a hydrofoil assembly downwardly extending from a forward section of the device and a flotation mattress attached to an upper surface of the device to provide for user comfort and to further allow the buoyancy of the device to be controlled.

Abstract: Polymetallic nodules are collected by means of a plurality of self-propelled vehicles which move upwards and downwards between the sea floor and a surface platform under the action of excess ballast which is partially and progressively released as the vehicle approaches the bottom. The vehicles are propelled along the sea floor by means of at least two supporting units each having at least one helical propulsion fin, the remainder of the ballast being released in order to return the vehicles upwards for docking, unloading and energy-recharging in the surface platform.

Abstract: The invention concerns a remote-controlled submersible drogue of the type used for carrying probes for marine research. The drogue is connected by a towrope or cable to a towing craft and comprises a lifting body which has a cross sectional shape which is dynamically stabilizing. In addition, the drogue includes a static stabilizer comprising a flat plate extending downwardly and rearwardly from the lifting body and the towrope is arranged to be attached at the tip of the front end of the drogue.

Abstract: A submersible boat is provided which utilizes a planing boat hull with a sharp bow and blunt stern. The submersible boat performs as a planing boat until it nears the target location. Then, the boat submerges in order to avoid detection. After this vessel submerges, it travels with the blunt end forward and the sharp end aft.