Apparatus and method for penetrating a barrier

[0001] 1. Field of the Invention

[0002] This invention relates to penetrating warheads and, in particular, to a method and apparatus for penetrating a barrier.

[0003] 2. Description of the Related Art

[0004] In combat situations, it is often desirable to deliver a warhead or other munition into a target protected by barriers made of concrete, stone, blocks, masonry, or other such materials. The materials may be reinforced with other structures, such as reinforcing bars, mesh, wire, fabric, and the like. Historically, projectiles employ a single warhead that can both penetrate the barrier and inflict damage on the target protected by the barrier. Such warheads may include large amounts of explosives to be effective, which, in turn, may increase the overall size and weight of the projectile used to deliver the warhead. Further, the size of the resulting opening in the barrier may be smaller than the diameter of the projectile, thus limiting the size of a follow-on warhead. If the barrier is particularly strong, the warhead's energy may be expended in penetrating the barrier with little effect on the target.

[0005] Projectiles have also been developed that use the projectile's kinetic energy to penetrate such barriers while carrying a warhead. Some barriers, however, may have enough strength to prevent the projectile from penetrating. Further, the impact of the projectile on the barrier may, in some situations, render the warhead inoperative or less effective. Additionally, structures within the projectile that contribute to the projectile's penetrating capability may cause the projectile to be heavier than desired.

[0006] It also may be desirable in some combat situations to penetrate a barrier so that personnel may pass therethrough. Typically, explosives are hand placed onto the barrier and then detonated, or multiple ballistic rounds are launched against the barrier to breach the barrier. These conventional methods may require significant knowledge by combat personnel in their use and may add an unacceptable amount of time and risk to the combat operation.

[0007] The present invention is directed to overcoming, or at least reducing, the effects of one or more of the problems set forth above.

[0008] In one aspect of the present invention, a penetrator is provided. The penetrator includes a shaped charge warhead defining a bore therethrough, an augmenting warhead disposed within the bore, and a detonating mechanism coupled with and capable of detonating the shaped charge warhead and the augmenting warhead.

[0009] In another aspect of the present invention, a projectile is provided. The projectile includes a shaped charge warhead defining a bore therethrough being disposed within the projectile, an augmenting warhead disposed within the bore, and a detonating mechanism disposed within the projectile and being coupled with and capable of detonating the shaped charge warhead and the augmenting warhead.

[0010] In yet another aspect of the present invention, a method is provided. The method includes at least partially perforating the barrier to form a slug and dislodging the slug from the barrier.

[0011] The invention may be understood by reference to the following description taken in conjunction with the accompanying drawings, in which the leftmost significant digit(s) in the reference numerals denote(s) the first figure in which the respective reference numerals appear, and in which:

[0012] FIG. 1 is a stylized, partial cross-sectional, exploded side view of a penetrator according to the present invention;

[0013] FIG. 2 is a stylized, end view of the penetrator shown in FIG. 1;

[0014] FIGS. 3-5 conceptually illustrate, in cross-section, a use of the penetrator of FIGS. 1 and 2 to penetrate a barrier;

[0015] FIG. 6 is a top, plan view of a first embodiment of a penetrator according to the present invention;

[0016] FIG. 7 is an end view of the penetrator shown in FIG. 6;

[0017] FIG. 8 is a cross-sectional view of the penetrator shown in FIG. 6 taken along the line VIII-VIII;

[0018] FIG. 9 is a fragmented, partial cross-sectional view of a projectile enclosing a penetrator according to the present invention;

[0019] FIG. 10 is a top, plan view of a second embodiment of a penetrator according to the present invention;

[0020] FIG. 11 is a cross-sectional view of the penetrator shown in FIG. 10 taken along the line XI-XI;

[0021] FIG. 12 is an end view of a third embodiment of a penetrator in a stowed configuration according to the present invention;

[0022] FIG. 13 is a side view of the penetrator shown in FIG. 12 in the stowed configuration;

[0023] FIG. 14 is an end view of the penetrator shown in FIG. 12 in an operational configuration; and

[0024] FIG. 15 is a side view of the penetrator shown in FIG. 12 in the operational configuration.

[0025] While the invention is susceptible to various modifications and alternative forms, specific embodiments thereof have been shown by way of example in the drawings and are herein described in detail. It should be understood, however, that the description herein of specific embodiments is not intended to limit the invention to the particular forms disclosed, but on the contrary, the intention is to cover all modifications, equivalents, and alternatives falling within the spirit and scope of the invention as defined by the appended claims.

[0026] Illustrative embodiments of the invention are described below. In the interest of clarity, not all features of an actual implementation are described in this specification. It will of course be appreciated that in the development of any such actual embodiment, numerous implementation-specific decisions must be made to achieve the developers' specific goals, such as compliance with system-related and business-related constraints, which will vary from one implementation to another. Moreover, it will be appreciated that such a development effort, even if complex and time-consuming, would be a routine undertaking for those of ordinary skill in the art having the benefit of this disclosure.

[0027] Turning now to the drawings, FIGS. 1 and 2 conceptually illustrate a penetrator 100 according to the present invention for penetrating a barrier 102. The penetrator 100 may be used to penetrate the barrier 102 made of concrete, stone, blocks, masonry, or other such materials, including those reinforced with other structures, such as reinforcing bars, mesh, wire, fabric, and the like. The penetrator 100 comprises a shaped charge warhead 104, being generally annular in shape in the illustrated embodiment, and an augmenting warhead 106 disposed within a bore 108 defined by the shaped charge warhead 104. The term generally annular, as it applies to the shaped charge warhead 104, means having an overall ring-like shape, including a circular ring, an oval ring, a polygonal ring, or the like.

[0028] Generally, the shaped charge warhead 104 is a directional warhead having an explosive portion 110 and a liner 112. Forces resulting from detonation of the explosive portion 110 collapse the liner 112, form it into a jet, and propel it toward the barrier 102. The augmenting warhead 106 includes an explosive portion 114 and a flying plate 116. The flying plate 116 is propelled toward the barrier 102 upon detonation of the explosive portion 114, which is detonated concurrently with or shortly after the detonation of the explosive portion 110 of the shaped charge warhead 104.

[0029] FIGS. 3-5 conceptually illustrate, in cross-section, a use of the penetrator 100 to defeat the barrier 102. The penetrator 100 may be stationary relative to the barrier 102 or propelled toward the barrier 102 as indicated by arrow 302. Upon detonation of the shaped charge warhead 104 (represented by an explosion graphic 304), a generally annular jet 306 is propelled toward the barrier 102 (as shown in FIG. 3) and impacts the barrier 102 (as shown in FIG. 4). Depending upon the construction of the barrier 102, the jet 306 may partially (as illustrated in FIG. 4) or completely perforate the barrier 102. In either case, the impact of the jet 306 on the barrier 102 at least reduces the thickness of the barrier 102 in a generally annular shape defining a slug 402, producing spall 404 (only one indicated) from a front surface 406 and a back surface 408 of the barrier 102. The term generally annular, as it applies to the jet 306 or the reduced thickness area of the barrier 102 produced by the jet 306, means having an overall ring-like shape that may be jagged or irregular at least in part, including a circular ring, an oval ring, a polygonal ring, or the like.

[0030] Still referring to FIG. 4, as previously mentioned, the explosive portion 114 of the augmenting warhead 106 is detonated concurrent with or shortly after the detonation of the shaped charge warhead 104 (represented by an explosion graphic 410), thus propelling the flying plate 116 toward the slug 402, as indicated by an arrow 412. The flying plate 116 impacts the slug 402, as depicted in FIG. 5, with sufficient force to dislodge the slug 402 from the remaining part of the barrier 102 and to create an opening 502 through the barrier 102. The opening 502 produced in the barrier 102 by the penetrator 100 may be used for passage of personnel therethrough or for passage of a secondary warhead (not shown) therethrough. The secondary warhead may be of any type known in the art.

[0031] FIGS. 6 and 7 illustrate a first embodiment of the penetrator 100 constructed in accordance with the present invention. The penetrator 100 includes a shaped charge warhead 602 having a generally annular configuration and an augmenting warhead 702, disposed within a bore 704 defined by the shaped charge warhead 602. In the illustrated embodiment, the augmenting charge 702 is held within the bore 704 by a plurality of supports 706 (only one indicated). One or more detonators 604 (a plurality of detonators 604 is illustrated) is affixed to an aft portion 606 of the shaped charge warhead 602 and is coupled with a firing mechanism (not shown in FIGS. 6 or 7). In the illustrated embodiment, the detonators 604 are spaced apart from one another and are interconnected by ribbon mild detonating cord 608, which is also affixed to the aft portion 606 of the shaped charge warhead 602, so that detonation may be more uniformly transferred around the aft portion 606 of the shaped charge warhead 602.

[0032] Further, the detonators 604 are coupled with one or more detonators 610 affixed to an aft portion 708 of the augmenting warhead 702 so that the shaped charge warhead 602 may be detonated no later than the detonation of the augmenting warhead 702. The one or more detonators 604 and the one or more detonators 610 comprise a detonation mechanism. In the illustrated embodiment, the detonators 604 are coupled with the detonator 610 by ribbon mild detonating cord 612. Alternatively, the detonator 610 may be coupled with a separate firing mechanism (not shown in FIGS. 6 or 7) or the detonators 604 and the detonator 610 may be coupled to the same firing mechanism (not shown in FIGS. 6 or 7).

[0033] FIG. 8 is a cross-sectional view of the penetrator 100 depicted in FIGS. 6 and 7. The shaped charge warhead 602 comprises an explosive charge 802 partially encased by a casing 804. The explosive charge 802 may be made of any explosive material known in the art having a high detonation velocity and/or high brisance, e.g., materials containing HMX (cyclotetramethylenetetranitramine), an HMX blend, RDX (cyclotrimethylenetrinitramine), an RDX blend, LX-14 (an HMX/estane blend), or the like. Generally, a high detonation velocity explosive is characterized as that having a detonation velocity of at least about 6000 meters per second.

[0034] Still referring to FIG. 8, a forward face 806 of the explosive charge 802, in the illustrated embodiment, is generally V-shaped in cross-section, having an included angle A1 within a range of about 30 degrees to about 60 degrees. A liner 808 is affixed to the forward face 806 in any way known to the art and, in various embodiments, may be made of copper, a copper alloy, or any other material generally known in the art as being appropriate for shaped charge liners. Upon detonation of the explosive charge 802, the liner 808 collapses inwardly, as indicated by arrows 810, and is projected forward as a jet (e.g., the jet 306 shown in FIGS. 3 and 4), as indicated by arrow 812, to impact the barrier 102 (shown in FIG. 1 and FIGS. 3-5) and produce the slug 402 (shown in FIGS. 4 and 5).

[0035] The augmenting warhead 702 includes an explosive charge 814 generally encased by a casing 816. The explosive charge 814 may be made of any high detonation velocity explosive material known in the art, as presented above in reference to the explosive charge 802. The augmenting warhead 702 further comprises a flying plate 818 disposed forward of the explosive charge 814, which is propelled against the slug 402 (shown in FIGS. 4 and 5) by the force of the detonated explosive charge 814. The flying plate 818 may be made of any material generally known in the art as being acceptable for flying plates, e.g., tantalum, a tantalum alloy, aluminum, an aluminum alloy, or steel.

[0036] Detonating an explosive charge generates a detonation wave propagating away from the point of detonation. When the explosive charge 814 is detonated, such a detonation wave (not shown) propagates from the detonator 108 toward the flying plate 818, finally impacting the flying plate 818 and propelling it toward the slug 404 (shown in FIGS. 4 and 5). Generally, it is desirable for the detonation wave to impact the flying plate 818 uniformly across an aft surface 820 thereof, so that the detonation energy may be efficiently transmitted to the flying plate 818 with less likelihood of the flying plate 818 being spatially skewed during flight.

[0037] One way of influencing the detonation wave such that it impacts the aft surface 820 of the flying plate 818 uniformly is to include a detonation wave barrier 822 within the explosive charge 814. The detonation wave barrier 822 may be made of any material generally known in the art as being appropriate for detonation wave barriers, e.g., polyethylene, polypropylene, or other explosively inert polymeric materials. Alternatively, the detonation wave barrier 822 may be a void within the explosive charge 814. The scope of the present invention encompasses the inclusion or omission of the detonation wave barrier 822 within the explosive charge 814.

[0038] Note that the invention admits wide variation in implementation. For example, the forward face 806 of the explosive charge 802, and thus the liner 808, may have any desired shape. In particular embodiments, the forward face 806 and the liner 808 may be, in cross-section, generally V-shaped, C-shaped, parabolic, trumpet shaped, or have any other shape generally known in the art as being suitable for use in shaped charges. The shape of the forward face 806 and the liner 808, as well as the size, shape, and type of the explosive charges 802, 814, the material and thickness of the liner 808 and the flying plate 818, and other characteristics of the penetrator 100, may be varied depending upon the type of the barrier 102 to be penetrated and the conditions under which the penetrator 100 is used. Any given implementation of the invention will balance these characteristics given the particular situation in which the penetrator 100 is used.

[0039] Returning to FIG. 5, as presented above, it may be desirable in certain situations to create the opening 502 in the barrier 102 so that a secondary warhead may be propelled beyond the barrier 102 to a target. FIG. 9 conceptually illustrates the penetrator 100 and a secondary warhead 902 disposed within a projectile 904. The projectile 904 includes a firing mechanism 906 coupled with the penetrator 100. Upon contact with the barrier 102 or at a predetermined distance from the barrier 102, the firing mechanism 906 is activated and, in turn, detonates the penetrator 100. The penetrator 100 creates the opening 502 in the barrier 102 and the secondary warhead 902 is propelled through the opening 502.

[0040] Generally, the overall diameter D (shown in FIG. 9) of the penetrator 100 is sized to produce an opening through which the secondary warhead 902 may pass freely. Thus, if the size of the secondary warhead 902 is increased, the diameter D of the penetrator 100 may also be increased, which may increase the overall weight of the projectile 100 and its contents. Alternatively, the configuration of the penetrator 100 may be altered to effect a larger opening through the barrier 102 generally without increasing the weight of the penetrator 100.

[0041] FIGS. 10 and 11 illustrate a second embodiment of the penetrator 100 comprising a shaped charge warhead 1002 and an augmenting warhead 1102. The augmenting warhead 1102 has a construction corresponding to the augmenting warhead 702, illustrated in FIGS. 7 and 8. The shaped charge warhead 1002, however, is generally frustoconical in overall shape, rather than being generally cylindrical in shape, as is the shaped charge warhead 602 (illustrated in FIGS. 6-8). Thus, when the shaped charge warhead 1002 is detonated, the resulting annular jet (e.g., the jet 306 shown in FIGS. 3 and 4) expands radially as it travels toward the barrier 102, as indicated by arrows 1004, until it reaches the barrier 102. The shaped charge warhead 1002 is capable of projecting the jet at an angle A2 that, in various embodiments, may range from about one degree to about ten degrees. Other aspects of the shaped charge warhead 1002 generally correspond to the shaped charge warhead 602, shown in FIGS. 6-8.

[0042] Rather than propelling the penetrator 100 toward the barrier 102, such as with the projectile 900, it may be desirable in some combat situations to position the penetrator 100 near the barrier 102 and detonate the penetrator 100. Accordingly, any variation of the penetrator described herein may be mounted to a portable stand, such as the portable stand 1202, illustrated in FIG. 12. It may be desirable, however, to alter the stowed configuration of the penetrator 100 so that it may be conveniently carried by personnel, such as within a backpack. FIGS. 12-15 illustrate a third embodiment of the penetrator 100 having a shaped charge warhead 1204 comprising an upper portion 1206 and a lower portion 1302 hingedly connected by a hinge 1304. FIGS. 12 and 13 depict the penetrator 100 in its stowed configuration, mounted on the stand 1202. FIGS. 14 and 15 illustrate the penetrator in it operational configuration, also mounted on the stand 1202.

[0043] Still referring to FIGS. 12-15, an augmenting warhead 1208 is supported from the shaped charge warhead 1204 by a plurality of supports 1210 (only one indicated). The construction of the augmenting warhead 1208 may correspond to the construction of any augmenting warhead (e.g., the augmenting warheads 702, 1102), including its method of detonation, disclosed herein. In the illustrated embodiment, the penetrator 100 further includes a plurality of detonators 1212 affixed to the shaped charge warhead 1204 proximate the hinge 1304 such that, when in its operational configuration, the detonators 1212 may detonate both the upper portion 1206 and the lower portion 1302 of the shaped charge warhead 1204. Further, a ribbon mild detonating cord 1402 may be affixed to an aft portion 1404 of the shaped charge warhead 1204 so that it may be more uniformly detonated along its aft portion 1214.

[0044] Note that the invention admits wide variation in implementation. For example, the detonators 1212 may be affixed to the shaped charge warhead 1204 in any number and in any location proximate the aft portion 1404 of the shaped charge warhead 1204. A detonator 1216 is affixed an aft portion 1218 of the augmenting charge 1210 and coupled with the detonators 1212 by ribbon mild detonating cord 1220. Other aspects of the construction of the shaped charge warhead 1204 may generally correspond to the construction of the other embodiments of the shaped charge warhead (e.g., the shaped charge warheads 602, 1002) disclosed herein.

[0045] Referring to FIGS. 12 and 13, the penetrator 100 may be prepared for use by placing it in its stowed configuration on the stand 1202. The upper portion 1206 of the shaped charge warhead 1204 may be then hingedly moved such that the penetrator 100 is in its operational configuration, as illustrated in FIGS. 14 and 15. The detonators 1214 may be coupled with a firing mechanism (not shown) of any type known in the art. The penetrator 100 is now ready for use. Alternatively, the penetrator 100 may be reconfigured to its operational configuration prior to placing it on the stand 1202.

[0046] This concludes the detailed description. The particular embodiments disclosed above are illustrative only, as the invention may be modified and practiced in different but equivalent manners apparent to those skilled in the art having the benefit of the teachings herein. Furthermore, no limitations are intended to the details of construction or design herein shown, other than as described in the claims below. It is therefore evident that the particular embodiments disclosed above may be altered or modified and all such variations are considered within the scope and spirit of the invention. In particular, every range of values (of the form, from about a to about b, or, equivalently, from approximately a to b, or, equivalently, from approximately a-b) disclosed herein is to be understood as referring to the power set (the set of all subsets) of the respective range of values, in the sense of Georg Cantor. Accordingly, the protection sought herein is as set forth in the claims below.