Abstract: Each unit of an array of submerged oceanographic devices is provided with a depth gauge of the air bubbler type. A typical depth gauge consists of a tube or air line that has one end fluidly coupled to a manifold; the other end of the air line is open. The open end of the air line is secured adjacent a corresponding submerged device. A small flow of air is established from the manifold, through the air line, to bubble out the open end into the water. A pressure transducer is fluidly coupled to the air line and senses the backpressure due to the hydrostatic water head existing above the submerged device. Means are provided for inhibiting pneumatic cross feed in the manifold between the respective air lines.

Abstract: An underwater gamma radiation survey probe adapted to be towed by a tow cable along the bottom of a body of water. The probe comprises a tubular shell with a nose cone having a waterproof connector for the tow cable. The nose cone closes one end of the tubular shell in a waterproof manner and an end plug closes the other end of the tubular shell in a waterproof manner. At least one weight of high density material is located in a lower half of the shell with that weight containing a cavity having an opening which faces the tubular shell. The weight maintains the orientation of the probe such that the opening faces downwards and a radiation detector in the cavity can detect radiation from the bottom surface.

Abstract: A seismic float is made in two parts--an upper foam-filled fiberglass hull and a lower steel hull, thereby resulting in a more stable float of reduced dimensions.

Abstract: The invention relates to an underwater cable cutting device which is used in combination with a geophysical exploration apparatus carrying a depth control unit. The depth control unit is provided with guiding planes which are protected by the cable cutting device mounted ahead of the depth control unit. The cutting device has a generally flat body having a curved forward portion and a pair of hook-shaped cutting portions on opposite rearwardly extending sides of the flat body for deflecting a cable from the depth control unit and severing the cable or mooring line with its cutting surface formed by the hooked-shaped cutting elements. The device is attached to an elongated housing and abuts a securing shank of the depth control unit, without requiring any modifications to be made to the depth control unit.

Abstract: A stabilizing device for an underwater towed body includes a keel attached o the bottom surface of the towed body to provide for any major correction for its rolling motion. Any finer correction of the rolling motion of the towed body is accomplished by moving horizontally a trim weight housed inside the towed body. The horizontal movement of the trim weight is controlled by the power applied to the electric motor which is determined by the rolling motion sensor.

Abstract: A towline depressor (2) having forward and rearward ends with a main body portion (4) at the forward end. Wings (6) and (8) extend from the body with stabilizing fins (10) and (12) depending from the wings. A dorsal fin (14) having holes (16), (18) and (20) extends from the top center of the body for attaching the depressor to a towline. The holes permit attaching the towline at varying points relative to the center of gravity of the depressor.

Abstract: A marine acoustic array employs a plurality of sections connected together sequentially with the outer surfaces of said sections having a non-smooth configuration to create a water flow along the length of the array as it is towed through a water layer that causes sensors within the array to provide outputs having improved signal-to-noise ratios.

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 water fillable chute, to be employed as a submerged tractor device is cected to a plurality of wire severing grapnels by means of a metallic chain for sweeping command type river mines.

Abstract: A stabilizing device for an underwater towed body includes a vertically mble keel inside the towed body using an electric motor. Major part of the imbalanced torque of the tow cable provides rotation of the towed body. A final correction of the rolling motion of the towed body is accomplished by moving a keel weight housed inside the towed body. The extension of the keel weight is controlled by the power applied to the electric motor which is controlled from the surface ship. A sensor sends rolling motion information to the surface ship via the tow cable.

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: The invention relates to a method in production and laying a pipeline or a cable under water, comprising production of the pipeline/cable in a desired length, winding it onto a drum, transporting the drum and laying ramp on board a vessel and laying from the drum while the vessel is moving. Winding onto drum (9) is carried out with the drum being mounted in and carried by a drum carrier (10) on land. At a desired time the drum with wound pipeline is taken on board the vessel (13) by sliding drum carrier (10) on a pier (12) or the like, which in the horizontal plane has an overlapping positional cooperation with the correctly ballasted vessel (13,14) to a position in which drum carrier (10) can be taken over by the vessel (13) by a vertical relative movement between drum carrier (10) and a supporting structure for it on the vessel. Drum carrier (10) can then, if desired, be slid onto a supporting structure (15) to a desired position on the vessel and be made fast there.

Abstract: An apparatus for supporting a seismic transducer under water adjacent a towing vessel includes an elongated substantially rigid towing arm. A lower connector assembly is operably associated with the towing arm for connecting a lower end thereof to the transducer. An upper connector assembly is operably associated with the towing arm for connecting an upper end thereof to the vessel. The upper connector assembly includes a first pivot arrangement for permitting the lower end of the towing arm and the connected transducer to be lowered into the body of water. The upper connector assembly further includes a torsional support structure for resisting rotation of the towing arm about a longitudinal axis thereof. Preferably the upper connector assembly also includes a second pivot arrangement for permitting the lower end of the towing arm and the connected transducer to move laterally relative to the towing vessel.

Abstract: An apparatus for employing and retrieving a seaborne vehicle having a frable surface includes a muzzle and a cylindrically shaped cocoon. The muzzle is clamped to the vehicle and then pulled by a rope into the cocoon. Bladders within the cocoon are inflated with pressurized air to retain the vehicle. The vehicle can then be safely retrieved by hoisting the cocoon out of the ocean. Vehicle deployment is achieved by placing the vehicle in the cocoon, pressurizing the bladders with air, lowering the cocoon and attendant vehicle into the ocean, exhausting the air from the bladders, and then towing the cocoon so that water passing through apertures in the bow of the cocoon push the vehicle into the open ocean.

Abstract: A stabilizing system for use in conjunction with a crane/boom in which an ject is held fast to a foam cushion within the system. A hook that forms part of the system grasps a sling holding the object and secures the object against the foam cushion. The object can be aligned by being rotated or tilted while held fast to the cushion. The object is prevented from swinging and swaying, thereby greatly reducing danger.

Abstract: A cable wiper assembly for airborne sonar includes a housing suspended from a hoist used to rapidly raise and lower a sonar transducer at the end of a cable. The wiper assembly is interposed ahead of the cable-directing sheaves forming part of the hoist to strip away the sea water which adheres to the cable as it is pulled from the ocean. The cable wiper housing includes a series of internal grooves each of which contains and secures one wiper stage. Each stage includes a washer-like wiper of elastomeric material whose internal diameter is just slightly smaller than the cable diameter carried in a shallow cup-shaped holder having an internal port significantly larger than the cable diameter and secured by means of an upper washer-member overlying the wiper whose internal diameter is slightly larger than the diameter of the cable.

Abstract: A fairing 13 for an element is made up of body sections 17. Each body section 17 comprises a moulded plastics body which has an open recess or hollow 18 along its leading edge 19. The body section 17 becomes slightly wider to the rear of the leading edge 19 and then increasingly rapidly decreases inside along a smooth curve until reaching a trailing portion 20 which thins, at a much slower rate, to edge 21. The mouth of the hollow 18 is defined by lips 23 which are dimensioned to straddle a trailing portion of the cable 12.In use, the body section 17 automatically aligns along the line of movement of the cable 12 and the body is held against the cable. The arrangement is such that the body sections will compensate for sidewards forces or drags.

Abstract: A ship is provided with booms that may be extended outwardly from the ship. Arrays of geophysical devices of different genera are towed from the booms, in the water behind the ship. A UHF antenna is located on each boom. A line joining the two antennas defines a long reference base line for determining the absolute heading of the ship with respect to a meridian and to locate the absolute positions of selected towed geophysical devices with respect to two-dimensional space. The booms may be oriented along a line perpendicular to the ship's track, independently of the ship's heading for the purpose of maintaining the integrity of the geometric pattern of the arrays of the towed geophysical devices.

Abstract: A remotely-controllable, surface-referenced paravane for use in towing an object in a body of water at a controlled lateral offset from the pathway of the towing vessel is disclosed. The principal components of the paravane are a buoyant hull, a cambered hydrofoil shaped keel attached to the bottom of the hull and extending generally downwardly into the body of water, a remotely-controllable steering means, and a tow cable which connects the paravane to the towing vessel. Passage of the cambered hydrofoil shaped keel through the water generates a lateral force, similar to the lift generated by an airfoil, which causes the paravane to move laterally away from the pathway of the towing vessel in the direction of the lateral force. The remotely-controllable steering means is used to compensate for changes in the speed of the towing vessel or variations in wind, waves, or currents so as to maintain the lateral offset of the paravane within certain limits.

Abstract: A ship is provided with booms that may be extended outwardly from the ship. Geophysical devices of different genera are towed from the booms, in the water behind the ship. A UHF antenna is located at the outboard tip of each boom. A line joining the two antennas defines a long reference base line for determining the absolute heading of the ship with respect to a meridian and to locate the absolute positions of selected towed geophysical devices with respect to two-dimensional space. The booms may be automatically oriented along a line perpendicular to the ship's track, independently of the ship's heading.

Abstract: A method and apparatus are provided for towing and steering a seismic subarray from onboard a tow vessel. The outboard reach of the seismic subarray, relative to the vessel, is controlled by an adjustable bridle connected to the seismic subarray, and turning of the subarray in coordination with turning of the vessel is done using both the bridle and a rudder located at the rear of the seismic subarray.

Abstract: A towed underwater transducer assembly includes a spherical housing (10) suspended from a towing vehicle at the end of a cable (12). The housing includes mounting brackets (26, 28) located less than one-half of the circumference of the housing apart along a meridian of the housing (10) centered in the direction of tow with a bridle cable (24) extending between the mounting brackets including a turnbuckle (32) to adjust its tension and a mechanical stop (30). A grooved pulley wheel (22) is mounted at the end of the towing cable (12) with the bridle cable (24) riding in the groove and the pulley wheel (22) free to seek a position along the bridle cable (24) such that the projected line of the tow cable (12) passes essentially through the geometric center of the spherical housing (10) thereby causing the spherical housing (10) to maintain an essentially vertical orientation irrespective of variations in the speed of tow.

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: The invention provides a side scanning sonar apparatus for detecting gas bubbles in water. This apparatus transmits low frequency sonar signals horizontally through the water and detects the resultant echoes. The echoes due to bubble columns can be discriminated from those due to simple reflection from solid objects. The invention also provides a special handling apparatus to permit launching and recovery of a towed sonar apparatus in which the upper part of the fairing is relatively fragile.

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 floatation apparatus is disclosed wherein a buoy for maintaining the near surface position of marine equipment is mounted on a hydrodynamically advantageous V-shaped frame to reduce frictional drag associated with towing surface equipment.

Abstract: A magnetic mine sweep has at least one block of permanent magnet material connected on each side in flux conducting relationship to respective distributor elements, typically of mild steel, which are secured to respective steel pipes which are closed to form cavities for providing buoyancy and for distributing the flux for mine sweeping purposes. Rigid plastic foam can be provided in the cavities for reserve buoyancy and stiffening purposes. A non-magnetic shroud extends around the block of permanent magnet material.

Abstract: Stabilized underwater apparatus (34) which is for being towed or tethered and which comprises a cylindrical body portion (40) provided with at least two stabilizers (74), the stabilizers being elongate such that they extend over a major portion of the length of the apparatus, the stabilizers being of a plate-like construction, the stabilizers extending in a plane substantially parallel to the adjacent surface of the cylindrical body portion, and the stabilizers being spaced apart from the adjacent surface of the cylindrical body portion.

Abstract: A method and apparatus are provided for recovering a towed body to onboard a towing ship while the towing ship is underway. A saddle is employed in cooperation with a rudder to engage one end of the towed body and, subsequent to engagement, the saddle means is slid forward to engage the opposite end of the towed body.

Abstract: Device for laterally shifting an assembly of apparatuses such as seismic streamer towed behind a ship, with respect to the ship route, comprising a profiled wing, connected to the assembly through a single cable, at the lateral end parts of which are formed two profiled caissons and whose central part therebetween is thinner and is provided in the middle with a profiled central rib extending from the leading edge to the trailing edge of the wing and protruding downwardly at said last edge beyond the height of the caissons.

Abstract: The invention relates to a container for the ground material removed by a ground working device, for example, a mud plough or a suction device from the bottom of a watercourse. Such a container is known in the form of a compartment trough moved by the tugboat of the mud plough or the hopper barge. A disadvantage of such a container is that it is heavy and hence transportable only with difficulty while it is expensive and cannot be emptied by a simple procedure. The invention has for its object to obviate these disadvantages and provides to this end a container of the kind set forth in the preamble constructed in the form of a flexible bag that can be connected with the ground working device.

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 funnel construction for a dipping sonar system carried in a helicopter includes the opening to a cylindrical housing of glass epoxy material for storing an underwater transducer which is deployed by suspending it into a body of water at the end of a thin cable. The housing opening includes a flared funnel structure including an entrance aperture member of thin wall aluminum alloy, a backing structure including a frustoconical strut member secured to the bottom of the helicopter and a resilient foam material positioned between and bonded to the entrance aperture member and the strut member which permits the entrance aperture member to move somewhat when impacted by the transducer. The aluminum alloy material in the entrance aperture is very light and yet transfers the heat of friction from rubbing of the small diameter cable against itself sufficiently rapidly that very little wear or damage is caused to either the cable or the funnel structure from repeated high speed reeling cycles.

Abstract: A method for deploying towed instrumentation arrays from vessels having miple submerged hulls is disclosed. The method significantly reduces the possibility of the array abrading or fouling upon any submerged structure or part of the vessel.

Abstract: A hydrophone deployment apparatus is provided for an underwater vehicle, rein the apparatus includes an annular drum releasably mounted about the tail portion of the vehicle. A plurality of arms are pivotally connected to the aft portion of the drum and are capable of swinging from forward positions flush with the vehicle to aft positions behind the drum. A device is provided for enabling retention and selective releasing of the arms from the forward flush positions. A hydrophone is releasably mounted on the inside of one of the arms, and a cable is connected between the hydrophone and the vehicle with an intermediate portion wound on the drum. With this arrangement a release of the arms during travel of the vehicle will cause the drum to be released and the vehicle will swim away from the drum pulling the cable until it is completely off the drum, at which time the hydrophone is pulled from its mounting in the arm. At this time the drum is jettisoned and the hydrophone becomes operational.

Abstract: A system for deploying and retrieving a seismic source assembly from a marine seismic vessel. The system comprises a guide track which is secured to the underside of an upper deck of the vessel. The chain which absorbs most of the strain due to towing passes through the track and is safely confined therein during the deployment and retrieval of the source assembly. A connector is attached to the chain at each point where a seismic source and a buoy line is to be attached. As the chain is unreeled and as each connector approaches the track, a source and a buoy line is attached to that respective connector. The track is constructed so a connector on the chain with both a source and a buoy line attached can pass therethrough. This procedure is continued until the seismic source assembly is deployed. The procedure is reversed to retrieve the source assembly.

Abstract: A hydraulically-powered yo-yo reel for handling a marine seismic cable in shallow water. At the beginning of a recording episode, a partially reeled-in seismic cable is released to drift to a standstill behind a ship. Data are recorded. The cable is then accelerated to match the ships's velocity. Following the initial acceleration, the cable is superaccelerated as it is partially reeled in. A microprocessor adjusts a dwell time between recording episodes to compensate for small variations in the ship's velocity.

Abstract: Apparatus, such as a chute or boom, attached to the stern of a ship permits towed body to be launched and retrieved without damaging the hull of the ship. The chute includes a plurality of telescoping sections coupled to one another through a locking and release mechanism operated by a cable assembly. In a preferred embodiment, launch contemplates extension of the chute and activation of the cable assembly so that the chute telescopes open to a locked full extension. The towed body may then be released through the chute to its towing position. Retrieval involves first recapturing the towed body and drawing it up through the chute into the ship and then activating the cable assembly and retracting the chute so that the chute is telescopically folded back to its initial position with the towed body stowed in the chute ready for its next launch.

Abstract: A hydrodynamic device comprising first and second parts which are connected together such that the first part is movable from a storage position in which it lies adjacent to the second part to an operable position in which it upstands from and extends from one end portion of the second part, the second part comprising an elongate member having (a) a plurality of transversely extending hydrofoil elements, and (b) a tow bar for enabling a connection to be made between the hydrodynamic device and a towing vessel whereby the hydrodynamic device can be towed in water with the first part visible above the water and the second part submerged.

Abstract: A linear acoustic array for use in oceanographic work in either a towed or a vertically suspended configuration utilizes a flexible cable in which strands are woven or braided into a tube, the strands of which can be separated sufficiently to insert a hydrophone and multiplexer assembly at each of a plurality of specified locations therealong. Each hydrophone and multiplexer assembly is adapted to be readily connected into or removed from a two wire system.

Abstract: A hydrophone deployment apparatus is provided for an underwater vehicle, rein the apparatus includes an annular drum releasably mounted about the tail portion of the vehicle. A plurality of arms are pivotally connected to the aft portion of the drum and are capable of swinging from forward positions flush with the vehicle to aft positions behind the drum. A device is provided for enabling retention and selective releasing of the arms from the forward flush positions. A hydrophone is releasably mounted on the inside of one of the arms, and a cable is connected between the hydrophone and the vehicle with an intermediate portion wound on the drum. With this arrangement a release of the arms during travel of the vehicle will cause the drum to be released and the vehicle will swim away from the drum pulling the cable until it is completely off the drum, at which time the hydrophone is pulled from its mounting in the arm. At this time the drum is jettisoned and the hydrophone becomes operational.

Abstract: 1. In a device for sweeping a pressure ground mine, the combination of an ongated tow cable adapted to be towed laterally at a substantially fixed distance above and parallel to the bottom of a seaway, a mop-like array of lines having their proximal ends secured to said tow cable and having the major portion of length, including their trailing ends, dragging on the adjacent to the bottom of the seaway, said lines being individually provided with bristly thrums.

Abstract: The method is applicable for retrieving an anchor having an anchor buoy holding an anchor pendant line. A trailer buoy is connected to the anchor pendant line via a floatable line. A work vessel is fitted with a boom having a catch hook so positioned that the hook is several feet abeam of the vessel and at or below the waterline. Capture is achieved by sailing the vessel so as to cause the trailer buoy to pass between the vessel and the boom hook so that the boom hook snags the floatable line. The boom is swung out of the water and sternward so that the trailer buoy and a section of the floatable line are brought aboard the vessel, the floatable line then being used to retrieve the anchor pendant line. The floatable line may be in two sections to facilitate attachment to winches, cranes or other retrieval equipment.

Abstract: A coaxial strain cable tows a tube-like net-containing pod behind a ship. nsors on the pod carried beneath the ships wake detect incoming torpedoes and supply detection data via the coaxial cable to a shipboard processor. Processor commands return via the cable to a pod motor to drive rudders and maneuver the pod into the torpedo path. Drogue and main parachutes packed in the pod are released into the path by other cable-carried commands. Power for the motors and a 'chute release mechanism also is supplied through the cable. The main 'chute is formed of a low drag aramid fiber mesh strong enough to arrest the torpedo. Preferably, explosives carried by the 'chute destroy it.

Abstract: 1. In a torpedo detecting device of the class disclosed, the combination of n elongated hose-like member having a towing device secured to one end thereof whereby the member is adapted to be towed through a body of water, and means in said member and remote from said towing device for disconnecting said member at a predetermined point in closely spaced adjacency from the towing device comprising a helical coil of explosive fuse cord disposed only at said point and capable of sufficient explosive damage to sever the member substantially at said point, and a pair of electroresponsive detonators for firing said fuse cord, said detonators being disposed respectively in abutting relation to the ends of said cord.

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: A device employing a permanent magnet is used to provide a sweep for magnetically activated marine mines.

Abstract: A heave compensation system for an underwater towed seismic system of the kind in which a body containing a sound source and hydrophones is towed behind a ship, and a recording is made of echoes from the bottom and sub-bottom layers. An accelerometer in the towed body produces a signal indicative of the vertical acceleration of the body. The acceleration signal is double integrated within a frequency range having a low frequency roll-off to produce a position signal which is used to adjust the firing time of the source. If the fish heaves upwardly, the firing time is advanced; if the movement is downwards, the firing time is delayed. Preferably a pressure transducer in the fish produces a pressure signal which is also used to adjust the source firing time, for pressure variations below the lowest likely wave frequency. The crossover of the pressure and acceleration compensation systems is typically about 0.01 Hz.

Abstract: 1. In a mechanism for sweeping a pressure controlled mine arranged within a ody of water comprising a plurality of water entraining devices, each of said devices comprising a pair of pressure plates, a plurality of bracing members for maintaining the pressure plates of each pair in predetermined fixed space relation with respect to each other, a plurality of flexible tension members interconnecting said pairs of pressure plates whereby the plates are adapted to cause the water entrained between said plates to be moved sufficiently to reduce the pressure of the water adjacent the mine to a predetermined value as the mechanism travels over the mine, and means for causing movement of said mechanism above the mine.

Abstract: Preconditioning of towable, flexible electrodes having a conductive layer nsisting wires helically laid on a bouyant core, to preclude later birdnesting, is accomplished using a flange device having cylindrical mounting portions fixed to the aft end of the core and radially extending flange portions having a circular pattern of guide holes through which aft end portions of the wires pass loosely. The guide holes have their axes disposed at predetermined pitch and convergence angles.