Abstract: A method for operating submerged submarines and a submarine are disclosed which are used to camouflage submerged submarines which, while submerged and travelling, draw a trail of heated cooling water behind themselves. In order to reduce the risk of detection of such submerged submarines by means of heat-sensitive detectors, either the density of the heated cooling water is increased through the introduction of additives, or, the heated cooling water is brought, by mechanical means, to a depth far below the submarine for preventing heated-up cooling water to rise up to the sea surface.

Abstract: A motion compensation and tension control system (MCATS) for a surface vessel overboarding, umbilical cable supported, submersible payload is provided with a housing containing a pair of spaced parallel guide rods attached to oppositely disposed housing end plates. Two identical carriages, slidably disposed on the pair of guide rods, each include two parallel slide tubes rigidly attached by a cross plate and by an axle, with a plurality of sheaves rotatably supported by each axle. Motion of each carriage as a rigid body along the guide rods is elastically restrained by, either extension or compression springs. The surface vessel umbilical cable is received through an opening in one of the end plates, reeved around the two sets of sheaves, and mechanically connected to the other end plate. Wave induced surface vessel motion is transmitted through the umbilical cable and absorbed, or compensated for, by the spring restrained carriage motion before it reaches the submersible payload.

Abstract: A submergible vehicle capable of untethered, fixed depth operation is provided with a rigid walled buoyancy chamber (40) adapted for accommodation of varying volumes of water and buoyancy gas. The chamber is provided with a valving system to adjust the volumes of gas and water within the chamber and therefore control the operating depth of the vehicle. Gas is provided by a high pressure source (10) thereof, the gas also serving to positively pressurize a hull (15) of the vehicle to accommodate the compressive loading thereof by water exteriorly of the vehicle.

Abstract: A method and an apparatus are disclosed serving to reduce acoustic emission from submerged submarines in which vibrations from moving mechanical elements within an inner region are transmitted to an outer hull via a vibration transmission path. For decoupling the outer hull as completely as possible from the moving mechanical elements, for example periodically moving nuclear reactor control rods, the vibrations are actively damped. Means are provided for ascertaining the motion of the mechanical elements relative to the outer hull and for superimposing upon said motion of counter-motion of opposite direction.

Abstract: A submersible grappling system is designed for retrieving objects, such as, golf balls from the bottom or floor of a body of water and is made up of a tubular housing, a bladder at one end of the housing, finger-like retrieval elements at the opposite end of the housing and a gear column which serves to interconnect the bladder and retrieval elements so that when the gear column is driven in one direction, it will cause the bladder to be compressed within the upper end of the housing while forcing the retrieval elements downwardly and outwardly into surrounding relation to an object to be retrieved, and when the gear column is driven in the opposite direction will cause the bladder to be expanded upwardly away from the housing to increase the effective buoyancy while causing the retrieval elements to be retracted around the object and drawn upwardly into the housing.

Abstract: The present invention is directed to an offshore access system that includes a support frame designed to be supported by grating positioned above horizontal structural members of the offshore structure. A support sleeve is attached to the support frame. Within the support sleeve there is included a vertically slidable and rotatable post. A mobile works platform is attached to a lower end of the vertically slidable and rotatable post. The work platform has a U-shaped configuration in one embodiment to provide maximum access to vertical structural members.

Abstract: A six degree of freedom grabbing apparatus (20) allows normally open jaws (22) to be positioned in a desired location and orientation relative to a work platform (19), whereupon a single control locks the grabbing apparatus is the desired location and orientation. The jaws (22) are secured to the end of an arm (24). The arm (24) is attached to a shoulder joint (26). The shoulder joint allows the arm to rotate (37) and pitch (38). The shoulder joint is secured to a base unit (28), which base unit is slidably and pivotally connected to the work platform (19, 80), allowing the base unit (and hence the shoulder joint and arm) to move in the same plane, e.g., the x and y directions, as the work platform, and further allowing the base unit, shoulder joint and arm to yaw (39) relative to a given position on the platform. Six degrees of freedom are provided by the apparatus; jaw closing/opening; pitching, rotating, yawing, moving in the x direction, and moving in the y direction.

Abstract: A reduced-drag, axially symmetrical missile or submarine hull with rounded, tapered bow and stern portions, and a rounded central portion tapered, for drag minimization, along a curve defined by a Fredholm equation of the second kind framed so that the pressure coefficient remains constant at all points on the central portion. The missile is designed to travel within a fluid so that its drag coefficient is decreased, boundary layer detachment is avoided, and cavitation and instability phenomena are eliminated. The constant pressure coefficient is reached by following as a profile the natural track lines of the front portion which are joined to the rear portion.

Abstract: A method and apparatus for pressure compensating an under water housing which includes a tubular structure sealed around a hole in the housing dimensioned so that the mouth of an inflated balloon will form a secure seal there on so that the housing may be pressure compensated by blowing up the balloon and sealing the balloon mouth around the tube.

Abstract: This invention relates to a recoverable tethered platform system and to a tethered platform for use therewith. One end of a tether line is retained at a surface station while the majority of the line is initially mounted on a mandrel in the platform and is drawn from this mandrel as the platform descends. This permits more rapid descent of a platform since there are substantially no line drag forces to overcome during descent. During recovery, the line can be wrapped on a mandrel which is the same as the mandrel in the platform and this rewound mandrel may then be substituted for the empty mandrel in the platform for redeployment.

Abstract: A marine unit has an elongate payload-containing body, a plurality of legs each connected by a pivot at its inner end to the lower end of the body, and an actuator in the body for deploying the legs to cause the body to stand upright on the sea bed. The actuator is a double-acting constant displacement piston and cylinder arrangement connected to each of the legs by a link. The link is connected to the piston by a second pivot and to the leg by a third pivot, the geometry of the three pivots being such that the linkage is self-locking and reverse loads on the leg are not transferred to the actuator.

Abstract: A method and apparatus for pressure compensating an underwater housing by blowing up a balloon and sealing the balloon mouth around a conduit to pneumatically connect the balloon to the interior of the housing. The balloon is configured to change its appearance either structurally or via indicia to provide a variable indication as to what depth it will provide compensating air. The indication varies in response to the amount the balloon stretches to accommodate the air forced into the balloon as it is blown up.

Abstract: A remotely operated vehicle (ROV) provided with not less than three thrusters arranged in the longitudinal direction of a vehicle body. The center of gravity G of the vehicle body excluding a pendulum and the center of buoyancy B of the vehicle body including the pendulum are set in agreement with each other, and the pendulum is provided so that it can be turned around a Y-axis extending in the lateral direction of the vehicle body and passing the center of gravity G thereof.

Abstract: A self-propelled manned submersible vehicle of the type comprising a pressure-resistant capsule (1) serving as a cabin, ballast tanks (3, 8), releasable ballast (7), propulsion units (4) having propellers driven by electric motors, and storage batteries (42), the pressure-resistant capsule (1) comprises a peripheral window constituted by a vertical cylindrical sleeve (19) which is entirely transparent, the sleeve is of sufficient diameter to house a plurality of people sitting side-by-side, and extends upwardly from a hemispherical bottom (14) and downwardly from a spherical cap (16) which is extended by a cylindrical conning tower (21) which is closed by a hatch (22).

Abstract: The invention is related to a submarine vehicle for the deep ocean research. This vehicle is composed of a penetrator (1) and of a support structure (2 to 7). The vehicle descends by gravity due to a ballast disposed in the lower part (11) of the penetrator. Apart from this ballast, the vehicle can be recovered due to a discoupling of the ballast by an explosive bolt (13). After discoupling, the float clusters (8) located in the upper part of said support structure supply the mounting thrust necessary for transferring the vehicle up to the ocean surface. If this thrust is insufficient, a pyrotechnical device (15) can be provided, which inflates a bag and thus creates an additional thrust directed to the upside.The invention is particularly useful in the investigation at the deep ocean sea-bottom.

Abstract: A pressure equalizing cabinet for instruments intended to be submerged in water is described. The device includes a source of compressed air and a piston in a cylinder. One side of the piston is in communication with the interior of the cabinet and the other side is in communication with the ambient. The piston also mounts a needle valve at a port in a conduit between this source of compressed air and the cabinet interior. When the pressure in the ambient exceeds the internal pressure, the piston is displaced to admit a flow of compressed air into the cabinet. When the pressure in the cabinet exceeds the ambient the piston closes the valve. A bleed valve is also provided for venting excess pressure within the cabinet during ascent.

Abstract: A self-propelled submersible vehicle which comprises a hull and a cockpit defined within the hull, a transparent dome on the top of the hull formed with the cockpit and enclosure walls defining the cockpit within the hull. The cockpit is open ended at the bottom thereof, and the hull is non-watertight. Compressed air tanks are provided in the hull, and these tanks communicate with a regulator valve which provides a constant flow of air into the cockpit forming an air bubble providing a breathable section of the cockpit for the passengers. An air exhaust device is incorporated with the regulator valve assembly for controlling the volume of the air bubble within the cockpit in response to the water level within the cockpit.

Abstract: An apparatus for extending the depth range of an underwater pressure hull such as an underwater camera body by providing a means responsive to ambient pressure for equalizing the pressure between the hull and its environment.

Abstract: A submarine includes a body and two ballast tanks. The ballast tanks are moveable from an up or diving configuration to a down or beach configuration. With the ballast tanks in the diving configuration and full of water, the submarine normally floats awash, and can be caused to dive at shallow depths for sight-seeing. With the ballast tanks full of air and in the beach configuration, the body will float substantially out of water, and the submarine may be beached or brought to a wharf for easy boarding or debarkation. In the diving configuration, the submarine is identical above and below a horizontal central plane.

Abstract: An apparatus for carrying by a diver while underwater that provides information useful for enabling the diver to expeditiously and safely work on submerged vessels without the danger of tapping into an explosive gas. The invention is particularly useful for finding liquid/gas boundary in a submerged vessel or the pressure of liquid or gas behind the wall of a vessel. A transmitting transducer provides a low frequency acoustic tone burst that is transmitted toward the hull of the ship. The reflected signal from the inner surface of the hull is received by a hydrophone and processed. Electronic circuit means, responsive to the received signal, processes the signal and computes the location of a liquid/gas interface or the presence of liquid or gas behind the hull. A display provides indications of the computed values.

Abstract: A high speed vessel system comprises a surface-craft, a sub-craft, a pair of main foils, at least a pair of auxiliary foils, a narrow strut connecting the sub-craft with the surface-craft. The main propeller and main rudder are located at the stern end of the sub-craft hull. When the vessel system is cruising at a high speed, the surface-craft will be lifted above the water line mainly by the buoyant force of sub-craft hull. The foils will control rolling and pitching of the vessel system. The surface-craft and sub-craft will be connected by a separable ball joint (first embodiment) or a plurality of rotatable links (second embodiment) when the vessel system is in sea operation. The sub-craft can be raised up to the water surface level to minimize the draught of the vessel system when the system is resting in a harbor. The present vessel system is specifically designed for a sea going vessel of big size and large tonnage, which needs to cruise at high speed constantly.

Abstract: View port for an underwater vehicle, e.g. for a remotely operated vehicle (ROV) usable for underwater inspection, and provides a view port (2) which can form a component of a pressure hull of an underwater vehicle, and which can be sandwiched between hull portions (4) to provide a transparent section girdling the hull. Preferably, the view port can form a component of a substantially spherical pressure hull, the view port being sandwiched between two similar part-spherical hull portions. The invention further provides an underwater vehicle having a view port which forms a component of a pressure hull and which provides a transparent section girdling the hull. A camera (10) may be pivotally mounted in the hull so as to allow rotation of the camera to view through the port. A light source may be provided in the hull and arranged so as to allow light from the light source to be shone out through the view port.

Abstract: An apparatus and method for extending the depth range of an underwater pressure hull such as an underwater camera body by supplying gas to balance the internal hull pressure with the ambient water pressure. The balancing gas is supplied by a variable volume reservoir pneumatically connected to the pressure hull. The reservoir is reduced in volume by an increase in ambient water pressure to thereby increase the internal pressure of the system according to Boyle's Law. Conversely, a decrease in ambient water pressure results in an increase in the reservoir volume which reduces the internal hull pressure accordingly.

Abstract: A container for adapting a device such as a video camera, camera, strobe light, etc. for underwater operation by providing a flexible, waterproof container and a means to pressurize the container prior to or during immersion. In numerous embodiments, the apparatus includes a pressurizing means responsive to ambient water pressure.

Abstract: A submersible unit comprises a portable, open or closed bottomed pneumatic chamber mounted on flexible drive tracks controlled by personnel from the chamber for operation along the bottom of a body of water, on the surface, at intermediate levels, in the air and on land. A safety chamber, connected to the submersible unit by an extendable linkage, can limit the depth of submergence of the submersible unit, stores cargo and carries power. Flooded compartments in the submersible unit and the safety chamber are supplied with compressed air to control the supported load and depth of submergence. Various accessories carried by the underwater unit enable the performance of a number of different on and under the water and land based tasks. A special pneumatic circuit enables equipment and propulsion to be controlled by touch control panels. A majority of operations are contained within the machine to minimize contamination of surrounding areas.

Abstract: An actuator usable in a first fluid under a high pressure, e.g. on board a submarine operating at great depths to release or jettison ballast and wherein the first fluid is external to the submarine, comprises a plunger which is mobile by means of a spring and is held in place by a locking member. The plunger, its spring and the locking member are located within a frame which is filled with a second fluid, while a flexible skirt and two deformable sleeves enable the pressure of the second fluid to adapt constantly to that of the first fluid.

Abstract: A negatively buoyant tether cable management apparatus for use with a remotely-operated underwater vehicle is disclosed. The apparatus includes a cable climbing assembly, a depth sensor and a controller coupled to the climbing assembly and formed to actuate the climbing assembly to climb the tether cable when the cable management apparatus has been lowered to a predetermined depth. The climbing assembly includes a pair of powered, ribbed belts which are wrapped at least partially around the periphery of the tether cable at an acute angle to the cable. As the tether cable is lowered further, the climbing assembly climbs to maintain the depth and passes the tether cable out below or beyond the climbing assembly to enable maneuvering of the remotely-operated underwater vehicle with respect to the negatively buoyant cable management apparatus.

Abstract: A manipulator apparatus carried by a remotely operated vehicle is provided with a suction device capable of gripping underwater objects. The suction portion of the manipulator apparatus utilizes suction chambers isolated from the body of water. When fluid is removed from the suction chambers an appropriately shaped moveable wall moves inwardly thereby forming a suction cavity between the suction device and the object to be moved.The moveable wall may take the form of a rubber-like flexible membrane wall or a piston moveable within the suction portion of the manipulator apparatus.

Abstract: A manipulator apparatus carried by a remotely operated vehicle is provided with a suction device having a flexible membrane wall capable of gripping underwater objects. The suction portion of the manipulator apparatus utilizes expansion chambers isolated from the body of water in combination with the flexible membrane wall which when expanded outward contacts and forms a suction cavity between the manipulator object and the object to be manipulated.

Abstract: An A-frame has a winch head swingable from a cross-member and between its two arms. A docking member comprises an upper frame depending, by means of hydraulic rams, from the winch head and a lower frame swingable from the upper frame about an axis perpendicular to the axis about which the winch head can swing from the cross-member. Guides for a load-carrying line are provided on the frames.

Abstract: A vibration-isolating apparatus for protecting equipment from excessive vibrations. The apparatus discloses an equipment-carrying frame attached by shock-absorbing members to a guide member. The guide member is loosely fastened in operational relationship wth a drillpipe or casing to permit movement of the apparatus. The apparatus is lowered along the drillpipe or casing by a cable or other locomotive means controlled from the surface. Vibration of the drillpipe created by ocean currents or waveloading forces causes the drillpipe to impact and vibrate the guide member of the apparatus. The shock-absorbing members protect equipment attached to the frame by attenuating the excessive vibrations induced by the drillpipe on the apparatus. Shock-absorbing members of varying stiffness can be substituted to attenuate the differing vibrational forces exerted by each particular drillpipe.

Abstract: The submarine working equipment illustrated which may be a diver's auxiliary equipment includes a hollow body that is specially reinforced against bending moments and pressure forces acting upon it by means of structure defining flow channels, for driving elements, that angularly penetrate it and by means of pressure chambers supported in the body which are adapted to multiple uses. The equipment is held and supplied with power by a connecting and supply cable. A main grab on the forward end of the body is adjustable to facilitate clamping on a wide range of diameters the clamping of the equipment on pipes, wracks, etc. so firmly that the equipment itself or working arms mounted thereon (tool arms, auxiliary grabs, platforms etc.) are capable of taking substantial working loads despite the small dimensions of the equipment.

Abstract: A submersible watercraft has two hulls constructed as submarines disposed generally parallel to and spaced apart from each other. A submersible pilot's cab is disposed generally above the two hulls approximately in a longitudinal symmetry plane defined between the hulls. The two hulls and the pilot's cab are rigidly interconnected by tubular struts.

Abstract: A self-propelled spherical vehicle (10) for operation in a fluid medium utilizes an impeller (12) of approximately half the diameter of the sphere for propulsion. In addition to driving the vehicle, the impeller acts to draw the flow of fluid smoothly over the after part of the sphere, thus avoiding or minimizing the tendency of the fluid flow to separate from the surface and create turbulence. Compensation for impeller torque is effected in one embodiment by a series of non-rotating stator blades (14) carried coaxially of and immediately aft of the impeller and which are curved to counter the torque of the impeller on the vehicle. The stator structure is supported at the rear of the housing by brackets (18) including pivotal supports providing support in the vertical plane.

Abstract: An arrangement for sweeping mines having firing systems which are sensitive to magnetic fields is disclosed which utilizes a remote control mobile floating body with a built-in propulsion system. A magnetic field is generated within a group of permanent magnets located within the floating body in such a manner that these permanent magnets are either individually controlled or controlled as a group so that various types of magnetic field mines can be detected.

Abstract: A cage to retain an undersea vehicle therein and tether reel-in and play-out mechanism is provided. The cage includes a latch for retaining the vehicle in a "garage" portion. A tether drive assembly reels in and out the tether line through a bale which cooperates with a narrow, annular drum to retain the tether line in an annular, cylindrical coil having a width of a single strand of line. The bail, with or without cooperation from additional means, winds and unwinds the tether in the drum.

Abstract: Method and apparatus whereby an anode may be mounted on a subsea propulsion vehicle, transported to a selected portion of a platform substructure and then remotely and operatively connected to the substructure, as by explosively-actuated bolts.

Abstract: Apparatus for providing a stable platform for equipment to be employed in underwater environment includes a fin assembly for preventing uncontrolled azimuthal motion of the equipment when the fin assembly is suspended in the underwater environment to a level at which a current is present. The equipment is joined to a mounting which is rotatably positioned upon the fin assembly, and is oriented to a selected azimuth by the rotatable mounting in response to control signals received thereby, the fin assembly remaining at a fixed azimuthal orientation determined by the direction of the current as the mounting azimuthally displaces the equipment.

Abstract: A spherical vehicle for operation in a fluid medium utilizes an actuator disk or propeller of approximately half the diameter of the sphere for propulsion. In addition to providing the energy for driving the sphere, the actuator disk acts to draw the flow of fluid smoothly over the after part of the sphere, thus avoiding or minimizing the tendency of the flow to separate from the surface of the sphere and create turbulence. For aircraft launch, a heavy shroud protects the actuator disk propeller and assures that the vehicle will sink rapidly after impact. The shroud is jettisoned at a desired depth. Steering in pitch and yaw planes is effected through the use of a plurality of powered thrusters located at or just behind the circle of maximum diameter (with respect to the direction of motion) and selectively actuated by a guidance or control system. Alternatively a single reversible thruster may be used for steering in yaw combined with a movable internal weight for pitch control.

Abstract: An unmanned self-propelled submarine vehicle is provided with a material exchanger-container having a vertical axis of symmetry aligned with both the vehicle's center of gravity and its center of volume. The exchanger-container has a moveable diaphragm which divides the interior into two compartments, a lower ballast compartment equipped with an unloading apparatus and an upper compartment adapted to receive collected material. Ballast is unloaded during material loading to maintain the weight of the vehicle constant during loading.

Abstract: A twin-hull watercraft in which the two hulls are disposed parallel to and spaced apart from each other and rigidly connected by means of tubular struts. The hulls and struts take the form of tight pressure vessels which are provided with cells that can be flooded and blown. A pilot's cab designed as a third pressure vessel is arranged on a vertical superstructure above the hulls, approximately in the longitudinal center plane.

Abstract: A spherical vehicle for operation in a fluid medium utilizes an impeller of approximately half the diameter of the sphere for propulsion. In addition to providing the energy for driving the sphere, the propeller acts to draw the flow of fluid smoothly over the after part of the sphere, thus avoiding or minimizing the tendency of the flow to separate from the surface of the sphere and create turbulence. Steering in pitch and yaw planes is effected through the use of a plurality of drag pins located just behind the circle of maximum diameter (with respect to the direction of motion) and selectively actuated by a guidance or control system. A plurality of stub vortex generators are also located on the after side of the sphere and are angled to oppose the torque created by the propeller. The center of gravity is located substantially below the geometric center of the sphere.

Abstract: A device for underwater taking in and paying out of a submarine cable or tether feeding a remote controlled submarine. A stationary guide tube has a funnel above and below it for guiding a tether therethrough. The tether is moved by a power driven wheel projecting into the guide tube. A dome spaced above the guide tube is shaped to deflect the tether into an annular storage chamber around the tube.

Abstract: Apparatus for handling a submersible device, such as a diving bell, includes a winch mounted on a support structure and having a suspension cable with a free end at which the submersible device is suspended, a guide structure fixed to the support structure and having two guidance ramps, each having a portion thereof extending below a water surface, a traveller having two parallel side members with a guidance device thereon which slidably cooperates with the two guidance ramps, a pulley back including two upper pulleys secured to the guide structure and a movable lower pulley fixed to the traveller with the suspension cable passing over the upper and lower pulleys so as to form n strands, and a locking device for releasably connecting the submersible device to the traveller.

Abstract: 4. A towable sea-going vehicle for carrying communications equipment for in conjunctive cooperation with communications equipment of another vessel comprising:an essentially hollow body having openings in its walls for free flooding and self-bailing of said body;said body having an essentially rounded, gently pointed nose section and a V-bottom portion, said V-bottom portion providing a surface for the planing of said body on the surface of water and providing a face portion for contributing to the hydrodynamic lifting of said body when in an underwater position;buoyancy producing means located in said body to the extent that the weight of said body in air is substantially less than the excess buoyancy of said body when immersed in water;and said body having an upper cambered portion for producing lift when said body is in an underwater position;whereby said communications-carrying vehicle may be towed either submerged or on the water surface at speeds up to and in excess of 35 knots.

Abstract: An underwater apparatus is described for acoustically inspecting a submerged object at considerable depths such as the lower structural portion of an off-shore drilling rig to determine if the structure has internal defect which cannot be optically detected. The apparatus is intended to operate in depths of up to 500 meters. The apparatus includes an underwater craft for transporting both humans and equipment to the submerged object. The apparatus includes a hand held acoustical and optical probe that is movable by a diver over the surface of the submerged object. The probe includes an array of acoustical transducers that are sequentially activated to acoustically scan the interior of the object. The acoustical transducers are mounted in a flexible support material to accommodate the array to the contour of the surface. The probe additionally includes a real-time display of the acoustical information to assist the diver in effectively inspecting the object.

Abstract: A method and apparatus for increasing the safety and productivity of tunnel workers active in high pressure environments is disclosed. The workers are housed at an intermediate pressure over a "work week" of at least several days and are transported between the tunnel face and the life support chamber in which the workers are housed in a pressurized personnel transport chamber. The housing contains sanitary, sleeping, decompression, storage and dining facilities and is generally located at the tunnel entrance. In the preferred embodiment, the intermediate pressure is about half of the tunnel working pressure but not more than about 20 psig and preferably less than 17 psig. It is expected that a decreased incidence of bone related diseases and bends will result due to the reduced number of full decompressions from the tunnel work environment.

Abstract: A system for varying specific gravity of a submersible or any immersed obt under a pressurized environment which includes a compressible piston designed to collapse a certain amount proportional to the submersible's depth so that the specific gravity of the submersible or other immersed object varies and remains almost equal to the specific gravity of the surrounding medium such as water.

Abstract: A slightly negatively buoyant personnel-accommodating chamber is suspended from a pair of buoyant-link flexible drive loops engaging the under surface of an ice cover over the body of water in which the chamber is submerged. Propulsion of the chamber can be effectuated through the medium of a power driven sprocket wheel arrangement that propels the chamber along the buoyant drive loops which in turn are caused to "roll" along the under surface of the ice.

Abstract: A manned submarine includes first and second side-by-side chambers extending in a fore-to-aft direction. The first chamber is maintained at substantially atmospheric pressure and includes sleeping and eating compartments for ship-based personnel, and a galley. The second chamber is maintained at greater than atmospheric pressure and includes sleeping and eating compartments for diver personnel. Passages interconnect the chambers, enabling ship-based personnel from the first chamber to service diver personnel in the second chamber. The submarine carries guides which can be mated with corresponding guides on a piece of underwater equipment to stabilize the submarine against lateral movement and allow the equipment to be attached to the submarine for transport. The submarine carries weights which are placed on the water bed and connected to the submarine by initially slackened lines.