Abstract:
A watercraft immobilizing apparatus and system deployable from a marine vessel to passively defend against an attacking watercraft includes a towed array of entanglement lines. The entanglement lines can be stored on and supplied from one or more storage cartridges mountable on and deployed via outriggers and submersible rollers to foul and immobilize propellers and engine cooling intakes of attacking watercraft.

Description:
FIELD OF INVENTION 
     The present invention generally relates to a passive, non-lethal marine vessel defense apparatus and system that can immobilize attacking watercraft. 
     BACKGROUND OF INVENTION 
     Maritime piracy (as well as potential acts of terrorism) targeting both commercial and non-commercial vessels has become very prevalent in recent years. According to available data, there were approximately 160 recorded attacks globally in 2008, where a third of this figure resulted in successful attacks. Pirates have proven that the use of high speed conventionally powered watercraft is highly effective and very difficult to deter. Prior experience in the Gulf of Aden has shown that successful attacks are conducted during twilight hours, from astern of and on the port quarter of the targeted vessel. It is the general policy of insurance companies to pay the very high ransoms demanded for hijacked international flag vessels, cargoes and crews. The current deterrents being utilized generally favor the use of armed guards. However, international authorities do not recommend such danger prone and potentially lethal methods. 
     Therefore, there is a need for a primary, stand-alone, passive, non-lethal and cost-effective marine vessel defense apparatus and system that can immobilize an attacking watercraft (whether detected or undetected). 
     SUMMARY OF THE INVENTION 
     Generally speaking, the present invention is directed to embodiments of a simple to use, relatively inexpensive, non-lethal watercraft immobilizing apparatus and system that can be deployed from a marine vessel as a passive shield around assailable faces of the vessel to defend against attacking watercraft, providing effective immobilization, at a maximum range from the marine vessel, by fouling propellers and water intakes of the attacking watercraft, regardless of whether the attacking watercraft is or is not detected. 
     Embodiments of the present invention include a towed array of wires, SPECTRA lines or nylon lines (“lines”) just below the surface of the water, weighted for neutral buoyancy, and deployed from removable/replaceable cartridges (that can be disposed of after use or refurbished) mounted on various portions of the vessel. The lines can be biodegradable. An arrangement of secondary and possibly tertiary lines can also be deployed from the lines. 
     Banks of suspended, weighted, submersible dual rollers direct the lines fed from the cartridges, which can be deployed and recovered by means of motors, for example, including by remote control. Each bank features secondary winches at the extremities that can also be operated by electric motor. These winches hold the wire/line that deploys the weighted submersible dual rollers for each bank. The weighted dual rollers are configured to place the towed array below the surface adjacent to the cartridges. The weighted dual rollers may also be prevented from riding above the surface of the water via preventer wires, which can be led from the roller extremities to a strong point on deck forward of the roller installation. A main bank of storage rollers can be mounted off the vessel&#39;s transom (e.g., suspended not from outriggers, but from the vessel&#39;s existing aft structures, such as, for example, the stern bulwark). Two transom outriggers, one at each extremity, can deploy second and third banks of rollers. The weighted submersible dual rollers in the way of these aft outriggers are configured to be connectable to the extremities of the rollers of the main transom bank, effectively forming one rigid unit. Deep fins can be situated at the outer extremities of these rollers to prevent the lines of the towed side arrays from fouling the vessel&#39;s own propeller. Two additional outriggers can deploy fourth and fifth banks of rollers at the vessel&#39;s forward shoulders (port and starboard sides). These banks can be similarly fitted with powered submersible dual rollers to effectively deploy the side arrays and shield the vessel&#39;s sides. Each cartridge can supply multiple main lines and an array of secondary lines through the adjacent submersible rollers. The ends of each of the main lines for each cartridge can be held in a submerged pattern by weighted spreader bars, which can be suitably finned for improved stability. 
     It is therefore an object of the present invention to provide a passive, non-lethal, easy-to-use, and cost-effective defensive shield around a marine vessel to immobilize and thus repel attacking watercraft (whether or not such watercraft have been detected). 
     Still other objects and advantages of the invention will in part be obvious and will in part be apparent from the specification. 
     The present invention accordingly comprises the features of construction, combination of elements, and arrangement of parts that will be exemplified in the constructions hereinafter set forth, and the scope of the invention will be indicated in the claims. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       For a fuller understanding of the present invention, reference is had to the following description of exemplary embodiments taken in connection with the accompanying drawings in which: 
         FIG. 1  is a simplified plan view of a marine vessel deploying a watercraft immobilizing apparatus and system in accordance with an embodiment of the present invention, illustrating exemplary positioning of a main transom bank of storage rollers and lines, aft outrigger banks, forward shoulder outrigger banks, and forward outrigger stays; 
         FIG. 2  depicts the extremity (fitted with a spreader) of a cartridge&#39;s towed array of lines (staggered secondary line sequence) of a watercraft immobilizing apparatus and system in accordance with an embodiment of the present invention; 
         FIG. 3  is a stern (transom) view (including below the water line) of a vessel deploying a watercraft immobilizing apparatus and system in accordance with an embodiment of the present invention, illustrating exemplary positioning of a main transom line bank with six cartridges, cartridge mounts/bearings, main bank electric drive motor, submersible weighted dual rollers, supporting winch/motor, stern outrigger assembly, deep fin, and towed array lines (shown supplied from a single cartridge); 
         FIG. 4  depicts weighted sub-surface dual rollers of a main transom line bank and a stern outrigger bank (portside), cross connection, main support wires, deep finned side and stern towed arrays, and portside fore stay of a watercraft immobilizing apparatus and system in accordance with an embodiment of the present invention; 
         FIG. 5  is an aft view of a portside shoulder outrigger assembly with submersible weighted rollers of a watercraft immobilizing apparatus and system in accordance with an embodiment of the present invention; 
         FIG. 6  is a side view of a portside shoulder outrigger assembly with submersible weighted rollers of a watercraft immobilizing apparatus and system in accordance with an embodiment of the present invention; 
         FIG. 7  is a cross-sectional (portside) view through a main transom line bank and submersible weighted rollers of a watercraft immobilizing apparatus and system in accordance with an embodiment of the present invention; 
         FIG. 8  is across-sectional view through a cartridge of a watercraft immobilizing apparatus and system in accordance with an embodiment of the present invention; and 
         FIG. 9  depicts a loaded cartridge supplying primary lines, with secondary and tertiary lines, of a watercraft immobilizing apparatus and system in accordance with an embodiment of the present invention. 
     
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     Marine engines are designed to propel a watercraft by moving water in various ways, for example, through open or enclosed propellers, through jet engines and through cooling systems. It will be appreciated that the towed array according to embodiments of the present invention moves with this water into the attacking vessel&#39;s propellers, cooling intakes or jet intakes, hence fouling and stopping the engine(s). Any entangled lines due to this fouling will part as a result of the weight of the immobilized attacking vessel. 
     Referring now to the drawing figures,  FIG. 1  illustrates an exemplary coverage pattern of the sub-surface towed line array and positioning of the main storage and outrigger banks relative to the protected vessel. Preferably, there are five storage banks (transom, port quarter, starboard quarter, port shoulder, and starboard shoulder). It should be understood that the only locations on the vessel that need not be protected by towed arrays are the bow areas where the bow wave creates a highly dangerous position for smaller boats to attack. 
     Each storage bank can deploy cartridges including multiple main lines suitably spaced (e.g., approximately, four inches apart). The multiple main lines supplied by each cartridge (see, e.g.,  FIG. 9 ) can be weighted for neutral buoyancy and can be fitted with weighted end spreaders (see  FIG. 2 ). The spreaders can be finned for increased underwater stability and/or interlinked to adjacent spreaders. 
     The lines can be provided with secondary and/or tertiary sub-lines of similar or smaller diameter, with varying lengths and staggered placement of intervals (preferably, of not more than five feet) along the main lines of the towed array (see e.g.,  FIG. 2 ). The main bank (see, e.g.,  FIG. 3 ) desirably spans the entire width of the vessel&#39;s transom. Damaged portions of the towed array can be renewed/replaced by removing and inserting a new or reconditioned cartridge. Cartridges desirably include the neutrally weighted primary lines as well as the secondary and tertiary lines and any end spreader component. 
     Adjacent to the main transom bank are two stern quarter outriggers—port and starboard sides (see, e.g.,  FIG. 4 ). The stern outriggers are configured to deploy extensions of the main transom towed array to the full width of the protected vessel&#39;s parallel body. The length of the quarter outriggers can be proportional to the difference between the length of the main transom bank and the overall beam of the vessel. 
     The towed stern array extends aft of the vessel—desirably, not less than 3,000 feet. The forward shoulder outriggers deploy side towed arrays of desirably not less than twenty feet in width/span, off the port and starboard sides. These side towed arrays desirably extend aft at least 3,000 feet and overlap the stern mounted towed array, outboard of the deep fin positioned at the extremities of the stern quarter dual submersible roller. 
     The main transom bank may be fitted by steel brackets to the vessel&#39;s existing structures, such as the aft bulwark (see, e.g.,  FIG. 7 ). The body of this component supports multiple flanges that incorporate intermediate (preferably, stainless steel) shafts and bearings. The intermediate shaft ends are preferably notched to receive the removable stainless steel cartridge shafts (see  FIG. 8 ). These shafts can then be locked into place—e.g., by rotatable locking rings (see  FIG. 8 , element  8 F) positioned at each end in the way of the flanges. The cartridge shafts can have splines or key ways (see  FIG. 8 , element  8 D) to prevent the cartridges from rotating on the shaft. The complete shaft assembly can then be driven by a centrally mounted electric motor (see  FIG. 3 , element  3 C) that can be remotely controlled. This shaft assembly can also be fitted with a locking device to prevent forced rotation when the sub-surface array is deployed. Secondary winches (see  FIG. 3 , element  3 E) similarly powered by electric motors are preferably provided at the main transom bank. These winches store the support wires for the main transom bank dual submersible weighted rollers ( FIG. 3 , element  3 D, and  FIG. 4 ). The winches can be similarly locked when the dual submersible rollers are deployed. These submersible rollers are configured to place the towed array just below the surface of the water and immediately below the main transom bank. 
     When deployed, the stern quarter outriggers (see, e.g.,  FIGS. 3 and 4 ) are in a generally perpendicular position, but the outriggers can also be rotated parallel to the vessel&#39;s main axis and removed when not in use and locked in stowed or deployed positions. The body of the outrigger similarly supports multiple flanges that incorporate intermediate (preferably, stainless steel) shafts and bearings. The intermediate shaft ends are similarly notched to receive the removable cartridge shafts that are similarly locked in place. The complete quarter outrigger shaft assemblies are then driven by inboard mounted electric motors, which can be remotely controlled. These quarter outrigger shaft assemblies can also be fitted with locking devices to prevent forced rotation when the sub-surface array is deployed. Secondary winches similarly powered by electric motors are situated at the extremities of the quarter outrigger storage bank rollers. These winches store the support wires for the quarter outrigger bank dual submersible weighted rollers (see  FIGS. 3 and 4 ). These winches can be similarly locked when the dual submersible rollers are deployed. The submersible rollers are configured to lock into place adjacent to the main transom dual submersible rollers to form a rigid unit (see, e.g.,  FIG. 4 ). These units similarly place the towed array just below the surface of the water and immediately below the quarter outrigger banks. The outboard extremities of these submersible dual rollers can be fitted with deep fins (see, e.g.,  FIG. 3 , element  3 G) to prevent the towed side arrays from coming into contact with the protected vessel&#39;s own propeller(s). The submersible dual roller extremities may also be fitted with fore stays (see  FIG. 4 ) to prevent the assembly from riding aft and away from the vessel&#39;s transom. 
     The larger forward outriggers (see  FIGS. 5 and 6 ), situated at the port and starboard shoulders of the protected vessel, are similar in design to the preferably smaller stern quarter outriggers. These outriggers can also be rotated parallel to the vessel&#39;s main axis when not in use and locked in stowed or deployed positions. The body of the outrigger similarly supports multiple flanges that incorporate intermediate (preferably, stainless steel) shafts and bearings (see  FIG. 8 ). The intermediate shaft ends are similarly notched to receive the removable cartridge shafts which are similarly fixed by the rotatable locking ring (see  FIG. 8 , element  8 F). The complete shoulder outrigger shaft assemblies are then driven by inboard mounted electric motors which may be remotely controlled. These shoulder outrigger shaft assemblies can also be fitted with locking devices to prevent forced rotation when the sub-surface array is deployed. Secondary winches similarly powered by electric motors are preferably provided at the extremities of the shoulder outrigger storage bank rollers. These winches can store the support wires for the shoulder outrigger bank dual submersible weighted rollers see  FIG. 5 , element  5 G). These winches can be similarly locked when the dual submersible roller system is deployed. The submersible dual roller extremities can also be fitted with fore stays connected via bridles (see  FIG. 6 , element  6 I) to prevent the assembly from riding aft and away for beneath the shoulder outrigger assembly. 
     Accordingly, the present invention provides embodiments of a marine vessel defense apparatus and system, the novel characteristics of which provide a non-lethal, passive, cost-effective means to prohibit attacking watercraft from closely approaching a protected vessel whilst it is underway. 
     It will thus be seen that the objects set forth above, among those made apparent from the preceding description, are efficiently attained, and since certain changes may be made in the above constructions without departing from the spirit and scope of the invention, it is intended that all matter contained in the above description or shown in the accompanying drawings shall be interpreted as illustrative and not in a limiting sense. 
     It is also to be understood that the following claims are intended to cover all of the generic and specific features of the invention herein described and all statements of the scope of the invention which, as a matter of language, might be said to fall therebetween.