CROSS-REFERENCE TO RELATED APPLICATION

[0001] This application claims the benefit of U.S. Provisional Application No. 61/408,048 filed October 29, 2010, the disclosure of which is hereby incorporated by reference in its entirety.

STATEMENT CONCERNING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT

[0002] Not applicable.

FIELD OF THE INVENTION

[0003] This invention relates to devices for protecting marine assets from hostile vessels. Particularly, this invention relates to devices for arresting hostile marine vessels.

BACKGROUND OF THE INVENTION

[0004] In recent years, several types of marine vessels, such as military combat ships, commercial container ships, cruise liners, and the like, have been targeted in attacks by hostile individuals aboard smaller marine vessels, such as outboard engine fishing boats and pleasure craft including jet-propelled personal watercraft. In some cases, these individuals have caused damage by approaching the side of the target vessel and triggering explosives. In other cases, the hostile individuals have boarded the target vessel and held passengers captive in an attempt to secure a ransom.

[0005] These situations can be addressed in various manners, one of which includes avoiding the situation altogether by preventing hostile vessels from approaching the target vessel. This can be achieved by positioning a sub-surface and/or super-surface barrier apart from the side of the vessel to create a secured area that smaller vessels cannot enter.

[0006] Unfortunately, current protective barriers have a number of disadvantages. For example, lightweight and easily deployed barriers are typically easily damaged and cannot prevent relatively large and/or high-speed vessels from entering the secured area around the target vessel. On the other hand, barriers that are capable of arresting large and/or high-speed vessels typically include elongated rigid booms and pontoons for reinforcement. Such components significantly increase the weight of security barriers, thereby increasing the difficulty of deploying these barriers and increasing the size of anchors used with the barriers. Moreover, such barriers are not necessarily effective for stopping hostile vessels; instead, hostile vessels tend to be launched over these barriers upon contact.

[0007] As such, a need exists for improved marine security devices that are relatively lightweight, easily deployed, and capable of arresting large and/or highspeed hostile marine vessels.

SUMMARY OF THE INVENTION

[0008] In one aspect, the present invention provides a marine vessel arresting device for deployment in a body of water. The device comprises an upper vessel arresting guard that includes a plurality of upper ropes connected to define a plurality of generally rectangular upper openings. The device further comprises a lower vessel arresting guard that includes a plurality of lower ropes connected to define a plurality of generally rectangular lower openings. A plurality of floats is supported between the upper vessel arresting guard and the lower vessel arresting guard. The device further comprises a plurality of supports supported by the plurality of floats and supporting the upper vessel arresting guard and the lower vessel arresting guard. Ballast is also supported by the plurality of supports. The plurality of floats, the plurality of supports, and the ballast are configured to hold substantially all portions of the upper vessel arresting guard above the surface in a generally upright orientation. These components are also configured to hold substantially all portions of the lower vessel arresting guard below the surface in a generally upright orientation.

[0009] In another aspect, the present invention provides a marine vessel arresting device comprising an upper vessel arresting guard that includes an upper rope connected to a plurality of upper transverse ropes. The device further comprises a lower vessel arresting guard that includes a lower rope connected to a plurality of lower transverse ropes. An intermediate rope is disposed between the upper rope and the lower rope and connects to the plurality of upper transverse ropes and the plurality of lower transverse ropes. A plurality of floats is supported by the intermediate rope. The plurality of floats is configured to float at a surface of the body of water to thereby position at least a portion of the upper vessel arresting guard above the surface and at least a portion of the lower vessel arresting guard below the surface. [0010] In yet another aspect, the present invention provides a marine vessel arresting device comprising an upper vessel arresting guard including an upper rope connected to a plurality of upper transverse ropes and a lower vessel arresting guard including a lower rope connected to a plurality of lower transverse ropes. An intermediate rope connects to the upper vessel arresting guard and the lower vessel arresting guard and is disposed between the upper rope and the lower rope. A plurality of floats is supported by the intermediate rope, and a plurality of support masts support the upper vessel arresting guard and the lower vessel arresting guard. The device further includes a plurality of weights supported by the plurality of support masts. The plurality of floats, the plurality of support masts, and the plurality of weights are configured to hold substantially all portions of the upper vessel arresting guard above a surface of the body of water in a generally upright orientation and substantially all portions of the lower vessel arresting guard below the surface in a generally upright orientation.

[0011] The foregoing and other aspects of the invention will appear in the detailed description which follows. In the description, reference is made to the accompanying drawings which illustrate a preferred embodiment of the invention.

BRIEF DESCRIPTION OF THE DRAWINGS

[0012] The invention will hereafter be described with reference to the accompanying drawings, wherein like reference numerals denote like elements, and:

[0013] FIG. 1 is a perspective view of a vessel arresting device according to the present invention deployed in the path of a hostile vessel;

[0014] FIG. 2 is a perspective view of the vessel arresting device of FIG. 1 arresting the hostile vessel;

[0015] FIG. 3 is a side view of an upper guard, a lower guard, support masts, and floats of the vessel arresting device of FIG. 1 connected to an anchored buoy shown in phantom;

[0016] FIG. 4 is a side view of a float of FIG. 3; and

[0017] FIG. 5 is a side view of an alternative embodiment of the vessel arresting device including an equipment raft.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

[0018] Referring now to the figures and particularly FIGS. 1 and 2, the present invention provides a less-than-lethal rope-type marine vessel arresting device 50 that is deployable in a body of water 10. The device 50 floats above and beneath the surface of the body of water 10 and is capable of arresting one or more hostile marine vessels 12 (e.g., marine vessels operated by terrorists, pirates, or the like). Unlike previous devices, the present marine vessel arresting device 50 is relatively lightweight, easily deployed, and capable of arresting both relatively small and relatively large and/or high-speed hostile marine vessels.

[0019] In general, the marine vessel arresting device 50 includes a rope-type upper vessel arresting guard 52 disposed above the surface of the body of water 10 and a rope-type lower vessel arresting guard 54 disposed at and beneath the surface of the body of water 10. A plurality of floats 56 are disposed between the upper and lower vessel arresting guards 52, 54 to provide buoyancy. In addition, the device 50 includes a plurality of weighted masts 58 that support the guards 52, 54 in the generally planar configuration shown in the figures. Together with the floats 56, the masts 58 also move and hold the guards 52, 54 in an upright orientation. In the following paragraphs, the manner in which the above components arrest various types of hostile marine vessels is first described and then the above components are described in further detail.

[0020] Still referring to FIGS. 1 and 2, in operation, smaller hostile vessels (e.g., jet-propelled personal watercraft) contact the upper vessel arresting guard 52 and cause the device 50 to tip backwards (i.e., the upper guard 52 tips away from the vessel 12 and toward the body of water 10). After the device 50 tips, the vessel 12 is supported by some of the ropes and thereby entangled and trapped on the upper guard 52. That is, if the vessel 12 attempts to move after the device 50 tips, contact between the vessel 12 and the ropes prevents it from doing so, and the vessel 12 remains trapped on the upper guard 52. The vessel 12 is not necessarily entangled by the lower guard 54; however, the lower guard 54 prevents the vessel 12 from diving under the device 50.

[0021] Larger hostile vessels (e.g. , outboard fishing boats, rigid hull inflatable boats (RHIBs), and the like) engage the marine vessel arresting device 50 in a similar manner. However, a larger hostile vessel has more kinetic energy than a smaller hostile vessel (provided that both vessels move at the same speed). Some of this energy is dissipated by contacting and moving the upper guard 52 and the lower guard 54 through the water. However, the guards 52, 54 can only move a limited amount at the surface because they are connected to anchors. As such, after the slack between the device 50 and the anchors is taken up, the device 50 dives underwater and pulls the entangled hull of the vessel underwater. Moreover, this action tips the lower guard 54 toward the surface to a position in which it is likely to entangle the propeller of the vessel. Entanglement of the propeller in the lower guard 54 can cause failure of one or more engine components (e.g., a propeller bushing) of the vessel. As such, the vessel cannot be returned to operation by untangling the device 50 from the propeller.

[0022] Referring now to FIGS. 3 and 4, the components of the marine vessel arresting device will now be described in further detail. Referring specifically to FIG. 3, the upper vessel arresting guard 52 includes a plurality of ropes that are capable of engaging and arresting a hostile vessel 12 as described above. In particular, the upper vessel arresting guard 52 includes an upper rope 60, three intermediate ropes 62, and a plurality of transverse ropes 64 connecting the upper and intermediate ropes 60, 62. The transverse ropes 64 are spliced or otherwise connected to the upper and intermediate ropes 60, 62 such that they extend generally perpendicularly therefrom. As such, the ropes 60, 62, and 64 define three rows of generally rectangular upper openings 66 in the upper vessel arresting guard 52.

[0023] In practice, the ropes 60, 62, and 64 may bow slightly due to their weight, but the openings defined by such ropes are still considered generally rectangular. In any case, rope structures that include generally rectangular openings have been found to more effectively arrest vessels than other shapes (e.g., loops).

[0024] The overall dimensions of the upper vessel arresting guard 52 preferably provide a structure that is capable of protecting relatively large areas without creating an excessively large device. In particular, the upper rope 60 and the intermediate ropes 62 may each have a length of approximately 30m, although other lengths may alternatively be used. In addition, the transverse ropes 64 preferably have a length (and thereby provide the upper net 52 with a height) in the range of 90cm to 180cm and more preferably approximately 138cm, although other lengths may alternatively be used.

[0025] Similarly, the transverse ropes 64 are preferably spaced apart to provide an upper guard mesh (i.e., number of ropes per unit distance) in the range of 1.5 ropes/meter to 2 ropes/meter and more preferably 1.66 ropes/meter. Such a mesh has been found to permit several of the transverse ropes 64 to support an arrested hostile vessel 12 and thereby distribute its weight to several ropes. The mesh could be increased to distribute the weight of the vessel 12 to even more ropes, although such a modification would increase the weight of the upper vessel arresting guard 52.

[0026] The structure of the individual ropes 60, 62, and 64 provides the upper net 52 with relatively low weight and relatively high strength (i.e., the capability to arrest vessels having a power output of up to about 350hp and possibly having multiple outboard motors). In particular, each of the ropes 60, 62, and 64 preferably comprises braided polyethylene fibers having a breaking tension greater than 19,000 kgf. As such, the ropes 60, 62, and 64 may be 12x12 Plasma® rope available from Cortland Puget Sound Rope, Anacortes, WA. The upper rope 60 and the lowest intermediate rope 62 each preferably have a diameter in the range of 20mm to 25mm and more preferably 22mm. The other intermediate ropes 62 and the transverse ropes 64 each preferably have a diameter in the range of 9mm to 14mm and more preferably 1 mm. These rope sizes may be varied based on the potential threat level (i.e., specifications, such as size and power output, of hostile marine vessels that the device 50 is likely to encounter).

[0027] Still referring to FIG. 3, the lower vessel arresting guard 54 has a similar structure to the upper vessel arresting guard 52. In particular, the lower vessel arresting guard 54 shares the lowest intermediate rope 62 with the upper vessel arresting guard 52 and includes an additional intermediate rope 68, a lower rope 70, and a plurality of transverse ropes 72 connecting the lower and intermediate ropes 62, 68, and 70. The transverse ropes 72 are spliced or otherwise connected to the lower and intermediate ropes 62, 68, and 70 such that they extend generally perpendicularly therefrom. As such, the ropes 62, 68, 70, and 72 define two rows of generally rectangular lower openings 74 in the lower vessel arresting guard 52.

[0028] Like the ropes 60, 62, and 64, in practice, the ropes 68, 70, and 72 may bow slightly due to their weight, but the openings defined by such ropes are still considered generally rectangular.

[0029] The overall dimensions of the lower vessel arresting guard 54 are preferably similar to those of the upper vessel arresting guard 52. In particular, the lower rope 70 and the intermediate ropes 68 may each have a length of approximately 30m, although other lengths may alternatively be used. In addition, the transverse ropes 72 preferably have a length (and thereby provide the lower net 54 with a height) in the range of 60cm to 120cm and more preferably approximately 92cm, although other lengths may alternatively be used. Considering this height and the preferred height of the upper vessel arresting guard 52, the guards 52 and 54 preferably provide a combined height in the range of 1.5m to 3m and more preferably approximately 2.3m.

[0030] The transverse ropes 72 are preferably spaced apart to provide a lower guard mesh in the range of 4 ropes/meter to 7 ropes/meter and more preferably 5 ropes/meter. Such a mesh has been found to permit several of the transverse ropes 72 to entangle the propeller of a hostile vessel and thereby distribute propeller contact forces to several ropes. The guard mesh could be increased to distribute these forces to even more ropes, although such a modification would increase the weight of the lower net 54.

[0031] The structure of the individuals ropes 68, 70, and 72 provides the lower vessel arresting guard 54 with relatively low weight and relatively high strength. Like the ropes 60, 62, and 64, each of the ropes 68, 70, and 72 preferably comprises braided polyethylene fibers having a breaking tension greater than 19,000 kgf. As such, the ropes 68, 70, and 72 may be 12x12 Plasma® rope available from Cortland Puget Sound Rope, Anacortes, WA. The lower rope 70 preferably has a diameter in the range of 20mm to 25mm and more preferably 22mm. The intermediate ropes 68 and the transverse ropes 72 each preferably have a diameter in the range of 9mm to 14mm and more preferably 1 mm. These rope sizes may be varied as described above.

[0032] Referring now to FIGS. 3 and 4, the floats 56 provide buoyancy for the vessel arresting device 50. In order to provide buoyancy along the length of the device 50, the floats 56 are supported by the lowest intermediate rope 62 and spaced along its length. The floats 56 are preferably spaced apart at a pitch {i.e., number of floats per unit distance) in the range of 0.6 floats/meter to 0.8 floats/meter and more preferably 0.66 floats/meter. Such a pitch has been found to provide adequate buoyancy without significantly increasing the weight of the device 50. Regardless of the specific float pitch, the floats 56 are preferably generally spherical foam components having a diameter of approximately 20cm. Each float 56 also preferably has perpendicular internal passageways 76, one of which receives the intermediate rope 62 and the other of which receives one of the support masts 58.

[0033] Referring again to FIG. 3, each of the support masts 58 is a generally elongated rod comprising a material that is sufficiently rigid to support the upper vessel arresting guard 52 and the lower vessel arresting guard 54 as described above without significantly deflecting, e.g., carbon fiber, Delrin®, composite materials, or the like. However, these support structures 58 are also preferably somewhat flexible to permit bending without breaking or shattering when a vessel engages the device 50. Such flexible masts 58 dissipate some of the vessel's energy by elastically deforming; this advantageously reduces the amount of energy that is dissipated by moving the ropes and causing the device 50 to tip backwards. Moreover, such flexible masts 58 also permit the upper and lower guards 52 and 54 to collapse around and pull larger hostile vessels underwater.

[0034] The upper end of each support mast 58 may include a flag 80 or another type of marker such that the marine vessel arresting device 50 is easily visible. The opposite end of each support mast 58 includes a ballast weight 78 that, as the name implies, permit the device 50 to move in a self-uprighting manner and stay in such a position. That is, the weights 78 cause the masts 58 and guards 52, 54 to pivot about the floats 56 and assume a stable position in a vertical orientation if a portion of the device is tipped, e.g., by strong winds, large waves, or during deployment.

[0035] The marine vessel arresting device 50 may be anchored in various manners. For example and still referring to FIG. 3, the upper vessel arresting guard 52 may include eyelets 81 that connect to anchored buoys 82 disposed at opposite ends of the guards 52, 54.

[0036] The vessel arresting device 50 may be modified in other manners not explicitly described above. For example, the upper vessel arresting guard 52 and/or the lower vessel arresting guard 54 may have a different number of rows of generally rectangular openings. As another example, the upper vessel arresting guard 52 and the lower vessel arresting guard 54 need not share an intermediate rope. As another example, the transverse ropes 64, 72 may have a different length to provide the vessel arresting device 50 with a different overall height. As yet another example, the eyelets 81 may connect to mooring lines (not shown) extending from the shore, a marine facility, or the like. As yet another example, at least some of the ropes may include internal sensors capable of detecting faults or tampering (e.g., rope breaks or cuts). Exemplary sensors include fiber optics that provide a low-level signal if cut. As yet another example and referring to FIG. 5, one or more of the floats 56 may be replaced by an accessory raft 84 that supports one or more accessories (not shown), such as radar equipment, sonar equipment, video surveillance equipment, lights, or the like.

[0037] From the above description, it should be apparent that the present invention provides an improved device for arresting hostile marine vessels. In particular, the present marine vessel arresting device is relatively lightweight, easily deployed, and capable of arresting both relatively small and relatively large and/or high-speed hostile marine vessels. It should also be apparent that together the floats and the weighted masts provide the vessel arresting device with buoyancy, ballast, and the ability for the vessel arresting device to move to and maintain an upright orientation. Furthermore, it should be apparent that the present marine vessel arresting device is capable of demarking a secured area adjacent a marine asset. However, if a vessel attempts to enter this secured area, the vessel arresting device decelerates the vessel in a less-than-lethal manner.

[0038] A preferred embodiment of the invention has been described in considerable detail. Many modifications and variations to the preferred embodiment described will be apparent to a person of ordinary skill in the art. Therefore, the invention should not be limited to the embodiment described, but should be defined by the claims that follow.