Description:
BACKGROUND OF THE INVENTION
This invention relates generally to underwater weapons systems such as mines and torpedoes, and more particularly to a system that can detect and classify an underwater target and release a homing torpedo that seeks the target. The desirability of such a system lies in its ability to clandestinely detect, classify and destroy targets in a much larger portion of a body of water than can a conventional mine or torpedo.
Mines have been traditionally used to protect harbors, beaches and shipping lanes from attack by enemy submarines and ships. The theory is that the friendly forces know where the mines had been planted and can therefore avoid them, but the enemy forces do not have this knowledge. Because present day mines are activated to detonate by pressure variations caused by the hull of a passing ship, by changes in the surrounding magnetic field, and by short range acoustical detecting means, they have a limited range of effectiveness. Consequently, numerous mines must be layed, constituting a mine field or a row where enemy ships or submarines are likely to pass to strike or come within the short effective detection and kill range of at least one mine. The remaining mines may be wasted and mines the expended mine must be replenished.
Torpedoes and depth charges are traditionally for overt attacks on enemy ships and submarines. The torpedoes used may be of the homing type or preset to run on a predetermined course and depth to intersect the enemy target. They must be launched from nearby aircraft, ships, and submarines, and much effort is required to find or lay-in-wait for a potential target.
SUMMARY OF THE INVENTION
Accordingly, an object of the present invention is to provide a mine system having a greater range of surveillence and influence than conventional mines.
Another object of the instant invention is to provide a torpedo-mine system that detects and seeks out a target.
A further object of the present invention is to provide a torpedo-mine system that can lay-in-wait for considerable periods of time.
A still further object of the instant invention is to provide a torpedo-mine system capable of detecting and classifying an underwater target.
Still another object of the present invention is to provide a torpedo-mine system using a modern homing torpedo encapsulated for protection when anchored for long periods of time.
A still further object of the instant invention is to provide an underwater weapon system requiring fewer mines per area to maintain the equivalent threat of conventional mining, less logistic support, less time and manpower to plant a field, and therefore less cost as a weapons system.
Another object of the present invention is to provide a torpedo-mine system that discriminates against random surface traffic in preference to submerged submarine traffic.
A final object of the instant invention is to provide a torpedo-mine system having an anchor system that moors the torpedo-mine at a certain depth regardless of bottom depth.
Briefly these and other objects of the present invention are attained by the system using an encapsulated homing torpedo, the capsule or case being anchored by a cable or fine wire at a predetermined maximum depth and having acoustical detecting and classifying equipment for discriminating against surface targets for submerged targets. When the target is classified as a submerged man-made one, the capsule opens to permit a homing torpedo to escape, seek and attack a target.
BRIEF DESCRIPTION OF THE DRAWINGS
A more complete understanding of the invention and many of the attendant advantages thereto will be readily appreciated as the same become better understood by reference to the following detailed description when considered in connection with the accompanying drawing wherein:
FIG. 1 is a pictorial view showing the deployment sequence of the torpedo-mine system;
FIG. 2 is a block diagram of the detecting, classifying, and torpedo releasing operational sequence; and
FIG. 3 is a pictorial diagram of the anchor cable pay out system.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring now to the drawing, in FIG. 1 there is shown pictorially a cross-section of the sea 10 wherein an aircraft 12, a ship 14, and a submarine 16 are shown deploying a torpedo-mine system 18. The system is shown at the deployment position A as having initially separated into components comprising a casing 20, and an anchor 24 attached by an anchor cable 22 having an initial preset length of about 25 feet. The torpedo-mine system continues its descent to a shallow bottom mooring approximately 1,000 feet at B, where the anchor cable remains at a fixed length or to a deep bottom mooring at C where the anchor cable 22 has been payed out so the casing 20 is at substantially the same depth from the surface as in the shallow bottom moor at B.
For deep moors as at C, where the bottom exceeds the maximum depth desired for the case 20, controlled pay out of cable 22 is performed by the system shown in FIG. 2 to keep the case at a depth of approximately 1,000 feet. As shown in FIG. 3, the system on the anchor 24 comprises a plurality of hydrostatic switches 70, connected to an electrically operated brake 72, a sensor 74, circumscribing the cable 22, and a source of power 76. The anchor cable 22 is shown connected to and wound on a spool 78 having flanges 80. Adjacent to one of the flanges 80 is the brake 72 for stopping rotation of the spool. At points 25 feet apart on the cable 22, are markers 82, such as magnetized portions, metal bands, cable clamps, or the like. Of course, anchor cable 22 may be of any suitable material, such as fine wire. From considerations of strength and compact packaging requirements, a fine line of high-strength, monofilament material would be preferable.
As previously described, if the sea bottom is more than 1,000 feet below the surface, additional anchor cable will be payed out to maintain the case 20 at the 1,000 foot level. This is accomplished by the plurality hydrostatic switches 70, having rupture discs or pistons each of which are designed to operate at 1,000 feet, plus 25 foot increments between each of the plurality. When the anchor 24 is pulled down below 1,000 feet, a hydrostat 70 is actuated, releasing spool brake 72 to pay out 25 feet of anchor cable 22. When a marker 80 passes the sensor 74, the brake is reapplied to stop paying out cable. If the anchor does not yet touch bottom, the anchor 24 will sink deeper causing the next hydrostat to be actuated to release an additional 25 feet of cable. The cable will again stop by application of the brake when the next marker is sensed. This sequence continues until the anchor 24 reaches the bottom, leaving the case 20 vertically moored at a depth of somewhat more than 1,000 feet.
Referring now to FIG. 2 there is shown generally a block diagram of the operational components, indicating the sequence of events for finally releasing a homing torpedo 30. As shown schematically, the detection equipment, power supply, torpedo release mechanism, and other associated system operational components are house in the encapsulating casing. The torpedo is completely self-contained with the casing providing the ideal storage environment for long-term underwater deployment until target detection and torpedo launch.
After the encapsulated torpedo-mine system 18 has been deployed and anchored, a safing and arming mechanism 32 containing an arming bar 34, such as, for example a hydrostat switch, starts a delay timing device 36. After a suitable delay to allow the deployment vehicle to leave, a power supply 38 is turned on, supplying power to a passive transducer 40 and a programmer 42. The passive transducer 40, such as a hydrophone, beings listening for a potential target and when one is detected and after determining that it is a man-made noise signal, sends a signal to a signal response actuator 44 which actuates the programmer 42. Programmer 42 sends a signal to a coder 46 which, if it is satisfied that the target is real and not random environmental noise, turns on an active transducer 48. Transducer 48 then begins "pinging," i.e., transmitting a beamed acoustic sonar signal in a low trajectory to discriminate against surface traffic and concentrate on submerged traffic. During the quiescent state, between pings, the active transducer listens for a return echo from a target. When a return is received, the signal is set to a decoder 50. This decoder is essentially a frequency band attenuating filter which discriminates against acoustical returns from random sea surface and environmental noise and passing surface traffic. In other words it determines if it is a submerged man made target. When a submerged target produces a return echo, detected by the active transducer 48, the decoder 50 passes the signal to a range and size gate 52 preset to a maximum torpedo acquisition range and a minimum size return echo signal. If the echo is strong enough, indicating a real man-made target rather than marine life and within the preset range, it is therefor classified as a target and the signal is accepted and passed on to the programmer 42, already activated by the passive transducer 40 and the associated signal response actuator 44. The programmer 42 produces a commond signal and directs it to the torpedo release system 54, where the signal causes flooding valve 56 to open thereby causing the casing 20 around the torpedo 30 to fill with sea water. A hydrostat sensor 58 detects the presence of sea water at pressure and causes a lock release mechanism 60 to open the casing 20. The torpedo 30 is now free to swim out of the casing 20 as its sea water battery floods to energize the propulsion system and the homing system. The self-contained torpedo then independently searches for the underwater target, and when acquired, automatically steers itself to intersect and kill the target.
Obviously, numerous modification and variations of the present invention are possible in light of the above teachings. It is therefore to be understood that within the scope of the appended claims, the invention may be practiced otherwise than as specifically described.