Device for the disruption of explosive objects

Abstract

A device for generating a liquid jet, the device comprising an enclosure containing a plurality of formers, each defining a cavity partially enclosed by the former, each of the formers supporting an explosive charge, and a filler material within the cavity, the filler material being a liquid, a gel or a non-metallic solid that will liquefy upon detonation of the device.

Description

[0001] The present invention relates to a device for the disruption of explosive ordnance.

[0002] Bombs, mines and explosives employed by terrorists and criminals are most commonly improvised explosive devices (IEDs) rather than the conventional munitions (CMs) manufactured for military use. They differ from such military devices in that, with the exception of such small devices as may be made from steel pipe and end-caps, they are most commonly made using containers which are relatively less robust and are manufactured for other everyday purposes. Such containers may for example include paper and plastic bags, briefcases, dustbins and beer kegs. Particular problems are encountered when such IEDs are very large and their construction cannot be ascertained. An example is a large vehicle which is laden with explosive material and which may be provided with more than one means of initiation.

[0003] The walls of such containers are much more easily penetrated than are those of conventional munitions, and a commonly employed method of rendering them safe consists of projecting a mass of water at them. The intention of the method is the penetration of the container and the tearing of it apart, or the pressurising of it to the extent that it bursts, thereby separating the components so quickly that the initiation system does not have time to function.

[0004] The most common means of thus disrupting IEDs is a heavy steel gun barrel which employs a blank cartridge to discharge a mass of water. This has sufficient velocity to penetrate the wall of many IEDs but is much less likely to cause the explosion or deflagration of their contents than are projectiles of other materials such as metal. The very high thermal capacity of water limits the temperature rise of the projectile material much more than is imparted to metal projectiles.

[0005] Since the increments of water originating from the muzzle end of the gun attain a lower velocity than those increments originating from the breach end and accelerated along the entire length of the barrel, the projectile consists of a slug of water with a velocity gradient along its length with the rearmost components travelling fastest. This inherent instability causes the slug of water, once inside its IED target, to scatter violently sideways and to disrupt the target contents.

[0006] The effectiveness of such a water jet is mitigated by inherent limitations of velocity obtainable by means of such gun barrels as well as by the instability of the projectile. Muzzle velocities can be increased by the use of heavier and faster burning propellant charges, by longer barrels and by choking the barrel, but such increase is subject to the law of diminishing returns.

[0007] A further limitation of disruptors based upon the gun-barrel principle is the recoil generated. This exceeds the holding ability of many remote-controlled vehicles used for the deployment of such disruptors. If such a disruptor is fired with inadequate restraint, the gun then constitutes a potentially dangerous projectile capable of inflicting greater damage than many small or badly constructed IEDs.

[0008] One of my earlier inventions, described in British Patent Specification GB2292445, consists of a disrupter which combines the advantages of high explosive as a propellant with water as a projectile. Unlike conventional deflagrating propellants, high explosive does not need a heavy container to generate extremely high propulsive pressures and it imparts directionality to the aqueous projectile by a different mechanism. According to this invention, the device is in the form of a shaped charge and water, or some other liquid or liquescent substance, is used to line or to fill the cavity. Like conventional metal-lined shaped charges, this device may be used in radially symmetrical forms or in linear forms.

[0009] In its radially symmetrical form in particular, the velocity of the jet of water enabled it to penetrate the steel or iron body of a mortar bomb and, by suddenly increasing the pressure of the contents, to eject the fuse and booster without explosive reaction.

[0010] In its linear embodiment, an elongate explosive charge is provided with a cavity which is filled with water.

[0011] Since such charges are most conveniently designed using light plastics containers, the assembly disintegrates upon firing and no effective recoil is applied to the means of support. They may therefore be deployed by the smallest of remote-controlled vehicles.

[0012] Yet another invention generates a powerful linear jet of water by the simultaneous initiation of two elongate and parallel charges of high explosive each of which is placed along the long axis of a cylindrical container of water. Each charge increment generates a rapidly expanding cylinder of water and, as these two expanding masses collide, a flat elongate jet of water is generated and projected towards the target. A disadvantage of this apparatus is that a similar and equally energetic jet of water is projected in the rearward direction. Since disruptors of this type were intended for the disruption of large vehicle bombs, they are necessarily very large and cumbrous and use tens of kilogrammes of high explosive. One means of deployment of such a large disruptor is a remote-controlled vehicle of great expense which is destroyed as the disrupter functions. Further expense may be caused by the rearwardly directed jet and the shock wave produced by the device. This expense is perceived as especially regrettable if the target is subsequently recognised as having not been a functional IED in the first place.

[0013] In the case of each of the above inventions, a disrupter of a given size will, at a given distance from a target, strike a given area of that target. Since it may be considered necessary or desirable for the effective disruption of that target to strike a larger area of that target, it is necessary in each case either to use a multiplicity of disruptors, all initiated simultaneously, or to use a larger disrupter. The use of a multiplicity of disruptors increases the amount of explosive and the overall charge weight in proportion to the area of the target attacked but it complicates deployment and the means of initiation. Simple increase in the size of a single disruptor in order to strike a larger surface area maintains the simplicity of the arrangement but increases disproportionately the amount of explosive and the overall weight of the charge, and increases the penetrating power to an extent that may be undesirable. Doubling the width of the target which is directly attacked, for example, also doubles the height of the target which is attacked and increases the weight both of the explosive and overall weight eight-fold.

[0014] The present invention provides a device for generating a liquid jet, the device comprising an enclosure containing a plurality of formers, each defining a cavity partially enclosed by the former, each of the formers supporting an explosive charge, and a filler material within the cavity, the filler material being a liquid, a gel or a non-metallic solid that will liquefy upon detonation of the device.

[0015] The present invention also provides a device for generating a liquid jet, the device comprising an enclosure containing a former with a plurality of cavities each partially enclosed and supporting an explosive charge, and a filler material with each cavity, the filler material being a liquid, a gel, or a non-metallic solid that will liquefy upon detonation of the device.

[0016] The present invention also provides a device for generating a liquid jet, the device comprising an enclosure containing at least one former defining a cavity partially enclosed by the former supporting an explosive charge and a filler material within the cavity, wherein the filler material is a decontaminant.

[0017] The present invention may include the features of any one or more of Claims 4 to 19.

[0018] In this way, according to one aspect of the present invention, there is provided a disrupter with multiple explosive charges in a single outer envelope.

[0019] Such a disrupter can provide a well-defined, directed explosive charge, for example which can reproduce accurately the actual or anticipated profile of the target.

[0020] Additionally or alternatively, a number of the devices of the present invention can be placed together in a modular form to provide a large-area, uniform explosive charge.

[0021] In either form, such a charge can be light-weight and can be assembled quickly and easily.

[0022] An object of the present invention is to provide a practicable and convenient means of perforating the case of a large improvised explosive device, such as an explosive laden road vehicle, using high explosive as the propellant and water as the projected material; another object of the invention is to disrupt and disperse the contents of the target munition so rapidly that its initiation system is unable to function.

[0023] A particular application of the invention is the rendering safe of an IED consisting of a large vehicle laden with explosive or containing one or more bombs. It is unlikely that the extent of the explosive fill and the position and nature of the initiation system will be known at the time that the device is recognised as a bomb, or that a decision is taken to treat it as such. Though it may be assumed that certain parts of the vehicle are more likely to contain explosive than others, it is unlikely that the precise position of the initiation system can be ascertained with certainty even if preliminary entry is made by manual or remote means for the purpose of inspection. The presumption must be made that the perceived initiation system may, in fact, not be the real initiation system or that it is duplicated elsewhere. It may therefore be decided that the safest way to proceed in the disruption of the target is to attack that part of the vehicle which is perceived or suspected of containing an IED or explosive material over sufficient area and with sufficient violence to blow it out of the vehicle and disperse it before the initiation system has time to initiate it or, at least, a significant part of it.

[0024] In a preferred embodiment, the shape of the outer container used in the present invention is that of a flat cuboid. This makes it simple and practicable to arrange two or more disruptors so as to extend the area and shape of the target surface attacked. A parallel array of explosive backed semi-cylindrical formers is arranged against one large inner surface of the outer container with their longitudinal edges adjacent or closely spaced. The explosive charge is applied to either or both surfaces of each former and the space inside the semi-cylinders is filled with water. The area of the target surface which is struck by the projectile water thus depends upon the length of the formers and the overall width of the array. This arrangement provides a means of striking the area attacked with an approximately evenly distributed amount of energy while providing a charge weight which is proportional to the area.

[0025] In one simple embodiment of the invention, the explosive charge and its formers are placed within an outer container which is itself filled with water. This arrangement suffers the inconvenience of requiring a robustly water-tight outer container.

[0026] In another embodiment of the invention, the necessity of using a container with a sealed lid capable of containing water without leaking is avoided by employing a rigid outer container and placing a flexible plastics or rubber bladder in the D-sectioned space defined by the inside of each semi-cylindrical former and the flat surface upon which its longitudinal edges abut. These bladders are then filled with water.

[0027] The energy imparted to the jet generated by a water-lined or water-filled shaped charge may be enhanced by tamping the explosive, thereby prolonging the duration of the pressure applied to the projected water. A simple means of providing such tamping consists of applying a second body of water to the rear and sides of the explosive charge. This water may also advantageously be contained within one or more flexible bladders occupying the space between the inner wall of the outer case and the convex surface of the semi-cylindrical explosive charges. Such an arrangement has the additional advantage of quenching the hot gases generated by the detonating explosive and eliminating the flash, thereby diminishing considerably the incendive nature of the device. This is particularly desirable when disrupting bombs within, or in the vicinity of, motor vehicles or other highly inflammable structures.

[0028] It will be understood that the water may be placed in a single bladder and the explosive charges and their formers placed either within a fold of this liner or within this inflatable bladder. The latter arrangement brings the inconvenience of requiring a large sealable aperture for the insertion of these components.

[0029] In an advantageous embodiment, there is provided a multiplicity of outer envelopes, each of which contains a single former, and so designed that they may be joined together to constitute an array. Such an array might lie in a flat or curved plane such that the jets of liquid produced are parallel, convergent or divergent. By this means, complex charges may be easily assembled consisting of two or more modules. Thus the user, being equipped with a multiplicity of modules, can readily assemble a charge suited in size to a particular requirement.

[0030] In a variant, the former may have a parabolic transverse section to cause the explosive to impart a greater degree of collimation to the projected water.

[0031] In one form of the invention, there may be provided charge cases pre-filled with water (perhaps containing anti-freeze such as ethylene glycol or calcium chloride). Thus, fragility of plastic bladders is eliminated and requires only the positioning of a sheet of plastic explosive inside the cavity of the tamping component, inserting a means of initiation, placing the projectile component in place, and fixing the sandwich together.

[0032] In one form, the present invention is applicable to disruptors used for large targets, typically bombs in vehicles. However, the present invention is also applicable to disruptors which are used for smaller targets, for example briefcases, wooden boxes and plastics cases.

[0033] The present invention also provides a device for generating a liquid jet, the device comprising an enclosure with a former supporting an explosive charge, and at least one end-cap holding the former within the enclosure.

[0034] The device may include the features of any one or more of Claims 21 to 28.

[0035] The present invention also provides an array of devices, at least one of which as claimed herein, wherein the devices are in a single plane. The array may include the features of Claim 30 or 31.

[0036] The present invention also provides an end-cap for use with a device according to the present invention.

[0037] In order that the invention may more readily be understood, a description will be given, by way of example only, reference being made to the accompanying drawings, in which:

[0038] FIG. 1 is a transverse section of a disrupter in which the outer container contains a multiplicity of semi-cylindrical formers.

[0039] FIG. 2 is a transverse section of a disrupter in which the projected and tamping water is contained within inflatable bladders.

[0040] FIG. 3 is a former for imparting the necessary shape to an explosive charge to enable it to be used as a component of a liquid filled linear shaped charge.

[0041] FIG. 4 shows the initiation train of a disruptor containing three formers.

[0042] FIG. 5 is the exterior of a disrupter of the present invention.

[0043] FIG. 6 is a transverse section of another embodiment of disrupter of the present invention.

[0044] FIG. 7 is a view from below of another embodiment of disruptor.

[0045] FIG. 8 is a side view of the disruptor of FIG. 7.

[0046] FIG. 9 is a view of the longitudinal midline vertical section of the disruptor of FIG. 7.

[0047] FIG. 10 is a plan view of the rear component of the disruptor of FIG. 7.

[0048] FIG. 11 is a transverse section along lines A-A′ of FIG. 9.

[0049] FIG. 12 is a view of the inside of a conjoined pair of end-caps.

[0050] FIG. 13 is a longitudinal midline vertical section of an end-cap.

[0051] FIG. 14 is an outside view of an end-cap.

[0052] FIG. 15 is a view of a turret-like insert.

[0053] FIG. 16 is an end view of an array of three conjoined end-Caps

[0054] FIG. 17 is an end view of three end-caps in a convergent arrangement.

[0055] Referring to FIG. 1 of the drawings, it will be seen that the apparatus illustrated therein comprises a plastics box 1 with an approximately rectangular transverse section. Three semi-cylindrical plastics formers 2 are held against the inside of the lid 3. If a layer of high explosive is attached to the inner or outer surface of each former 2 and all remaining space is filled with water, detonation of the explosive projects the water within the formers 2 violently through the lid 3 of the box 1.

[0056] Referring to FIG. 2 of the drawings, an arrangement similar to that of FIG. 1 is provided with an inflatable plastics or rubber bag 4 in each of the formers 2. Each of the three bags 4 is provided with an integral nozzle 5 which passes through holes in the lid 3 in order to allow filling with water once the lid 3 is in place. A further bag 6 occupies the space 7 behind the formers 2 and is filled with water through the nozzle 8 which passes through one end-wall of the box 1.

[0057] Referring to FIG. 3 of the drawings, the former 2 for imparting the necessary shape to an explosive charge consists of a semi-cylindrical plastics extrusion. Its shape may conveniently be semi-cylindrical but other suitable concave shapes, including but not limited to a V-section or a parabolic shape, may also be used. A common form of explosive for application to such a liner consists of sheet explosive, typically between one and six millimetres thick, which is stuck to the outer or the inner surface. Alternatively detonating cord may be passed longitudinally to and fro between the ends along the outside of the former, passing through the notches and round the projections of the crenations 9 at each end. The explosive load may be increased by passing the detonating cord more than once between each corresponding pair of projections, or by passing in one direction along the outside of the former and back in the other direction along the inside.

[0058] Alternatively, light loads may be arranged by using less detonating cord, leaving the gaps between some adjacent projections empty. Sheet explosive may be used instead of detonating cord. It may conveniently be stuck to either surface of the former using an adhesive or double-sided sticky tape. One or more plastic cable ties 10 passing through pairs of holes in the former 2 provide a means of securing the tail of the detonating cord. If sheet explosive is used, a length of detonating cord 11 with a tubular explosive booster 12 at its end is secured so that the booster is urged into contact with the sheet explosive 13.

[0059] Referring to FIG. 4 of the drawings, a transverse section of the invention shows sheet explosive 13 applied to the backs of the formers 2 and the flexible bags 4 & 6 inflated with projectile water 14 and tamping water 15 respectively.

[0060] Referring now to FIG. 5 of the drawings, the end view of an assembled disruptor shows the lengths of detonating cord 16, 17 & 18 emerging through holes 19 in the wall of the box 1 and going to the point of initiation where a detonator 20 is held in contact with them. The detonating cord is held against the surface of the box 1 by means of a multiplicity of plastic ties 21. It will be appreciated that the devious paths taken by the three strands of detonating cord 16, 17 & 18 are so determined that each separate strand travels an equal distance between the point of initiation 20 and the former to which it leads in order that all strips of explosive 13 be initiated simultaneously.

[0061] The disrupter 30 of FIG. 6 comprises a former 31 with three semi-cylindrical recesses of which the central recess 32 is of greater volume than recesses 33 and 34. Bag 35 of water substantially fills recess 32, and bags 36 and 37 of sodium hypochlorite solution substantially fill recesses 33 and 34 The amount of explosive (not shown) for each recess is proportionate to the volume of the recess and the mass of the material in the recess.

[0062] In a variant, the amount of explosive in the central recess 32 is greater than the proportionate amounts in recesses 33, 34 by volume and mass, so that the overall explosive effect will be greater in the central region. Clearly, the proportions of explosive material, the nature of the filling material, and the amounts and density/mass of filling materials, can be changed as required to provide different profiles of explosive effect. All these variants can be used with the disrupter of FIGS. 1 to 5.

[0063] A particular advantage of this invention is that the device may be stored and transported with the explosive in situ, but containing no water. This considerably reduces the weight and susceptibility to damage by rough handling. When required for use, the inflatable bags may be quickly filled with water obtained locally without any need to open the outer container.

[0064] The invention is not limited to the use of detonating cord as a means of initiation. Sufficient simultaneity of initiation of each element can be assured by means of shock-tube detonators provided that equal lengths of shock-tube run between the point of initiation to the proximal part of each explosive charge increment.

[0065] The great advantages of using water as the working fluid in the invention are its suitable density, lack of flammability, fire-quenching and heat absorbing properties, cheapness, availability, and complete lack of toxicity; however, the invention is not limited to the use of pure water as its working fluid. Indeed, the use of separate flexible bags for containing the working fluid and the tamping liquid respectively enables the invention to be employed with two different fluids, of which one provides the projectile and the other the tamping and the means of modifying collateral effects. Thus, and by way of example, the water may have its density raised by the dissolution of inorganic salts, its coherence increased by the addition of long-chain polymeric substances such as the sodium salt of carboxymethylcellulose, and its fire quenching properties augmented by the addition of sodium borate or sodium bicarbonate. For use in cold climates the freezing point of the water may be depressed by the addition of such anti-freeze substances as ethylene glycol, methanol or calcium chloride. The tamping effect of the fluid surrounding the rear and sides of the charge may be enhanced by increasing its density. This may be achieved by the dissolution of inorganic salts or by the incorporation of solid, particulate, substances such as sand or sodium bicarbonate.

[0066] Water may also be replaced by a suitable pressed or melt-cast solid material. Since explosive materials are less easily initiated by the impact of materials of low melting point, suitable substances are inorganic salts with a high proportion of water of crystallisation. One such substance which has been found particularly effective is disodium hydrogen phosphate dodecahydrate. Another suitable material is sodium bicarbonate which, upon heating, decomposes with the liberation of water and carbon dioxide.

[0067] The invention is of particular usefulness if it is required to disrupt a device known or believed to contain a biological pathogen, such as a live bacterium or the spores thereof, or an extremely toxic chemical, such as a nerve gas. In this case, disruption of the target munition is likely to disperse the pathogen in the manner intended by the maker of the target. By the use of a concentrated solution of sodium hypochlorite, or some other suitable decontaminant, as the projectile liquid, any such dispersed target material will be intimately mixed with a finely divided cloud of decontaminant and thus rapidly neutralised.

[0068] A particular advantage of the invention is that it is a powerful disruptor suitable for large targets even when made such a size as to be easily portable by a single operator. This, as well as its flat, rectangular shape, enables arrays of similar charges to be quickly assembled on a fixed or mobile frame in order to form an array so configured as to attack a target in the most advantageous Way.

[0069] By way of example:

[0070] A disruptor having a similar cross-section to that shown in FIG. 4 was made in a plastics box 350 mm wide and 550 mm long with a height of 100 mm. Three semi-circular plastics formers were fitted, edge to edge, against the inner face of the lid. Each former was covered on its convex surface by a layer of Detasheet plastic explosive 6 mm thick. This gave a total explosive load of approximately 2.5 kg.

[0071] The disruptor was filled with water and placed opposite that part of a transit van within which were stood two plastic bins containing approximately 960 kg of explosive consisting of prilled ammonium nitrate sensitised by the addition of nitromethane and diesel and containing cartridges of gelignite. Initiation of the disruptor opened a wide hole in the distal side of the van and ejected the explosive-filled bins through the opposite side of the vehicle, most of which was also removed. The bins were ripped apart and the explosive they contained widely dispersed. There was no evidence to suggest that any of the explosive target material had been detonated. The vehicle did not catch fire.

[0072] FIGS. 7 to 15 show features of another form of disrupter 40 which consists of two major components, one being a water-filled enclosure 41 placed within the concavity in the explosive charge 42 and the other a water-filled enclosure 43 placed on the convex side of the explosive.

[0073] By providing enclosure 43 with a recessed area 44 extending for most of its length, a space is created to receive the explosive charge 42. The volume of this space is a function of the distance between enclosure 41 and enclosure 43 which is determined by the height of ridges 45 at each end of component 43 upon which the ends of enclosure 31 rest.

[0074] It is necessary for enclosures 41 and 43 to be held closely together after the explosive charge 42 has been placed between them. This is done by end-caps 46 into which the ends of both enclosures 41 and 43 may be fitted so that the peripheral walls 47 of the end-caps 46 constrain them. The end-caps 46 may be prevented from falling off the ends of enclosures 41 and 43 by providing them with one or more small projections 48 which fit into corresponding peripheral grooves 49 in the outer surfaces of enclosures 41 or 43 or both.

[0075] Since it is advantageous on occasion to fire a close array of charges simultaneously, these may conveniently be held in suitable juxtaposition by forming a multiplicity of end-cap sections in a linear array (see FIGS. 12, 16 and 17). Individual end-cap sections comprising such an array may be mutually attached by means of a pair of interlocking ridges 50 on each side. Thus the two major elements of disruptor 40 (namely enclosures 41 and 43) are supported, preferably but not necessarily in close proximity, with an explosive charge 42 trapped between them.

[0076] The disruptor 40 may comprise a single unit with two enclosures 41 and 43 having a charge between them. Alternatively, the disrupter 40 may be a linear array of parallel closely-spaced charges, all pointing in the same general direction. Additionally, disrupter 40 may be formed of two or more units arranged end-to-end in order to increase the overall length of the assembly.

[0077] The casing 41 of the assembled disruptor 40, which consists of the enclosures 41 and 43 with the explosive 42 between them, may conveniently be generally rectangular. Since, however, the water most adjacent to the longitudinal corners of casing 41 defining such a rectangle and most distal from the explosive charge 42 contributes little to the tamping effect on the explosive charge for which it is intended, these corners may advantageously be ablated. In this way, the total weight of the assembly may be reduced without diminishing significantly its performance. In order better to support casing 41, the end-caps may be provided with a correspondingly shaped internal wall 52 although retention of the generally rectangular peripheral wall of the end-caps facilitates the provision of a strong means of inter-attachment, such as the interlocking members 50.

[0078] A suitable method of producing the water-filled enclosures 41 and 43 is blow-forming. Though it is possible to form vessels with thick walls by this method, a greater volume of water and explosive can be contained within a given outer envelope by forming relatively thin walls. In order to reduce the tendency of liquid-filled, thin-walled vessels to undergo deformation as a result of internal hydraulic pressure, the peripheral grooves 49 may advantageously extend round the outward facing sides of casing 41 in planes perpendicular to the longitudinal axis of the charge.

[0079] The inner surface enclosure 43 can be depressed so as to provide space for the explosive 42. Space for the explosive could alternatively be obtain by the provision of a raised area of the other water-containing enclosure 41.

[0080] Further depressions 55 can be provided in either water-filled components to accommodate such other pieces of priming explosive as may ensure reliable initiation of the main charge 42 by a primary means of initiation such as a detonator.

[0081] It is desirable that explosive charges incorporate a strong means of attachment of the means of initiation, which include an electric detonator, a shock-tube detonator, a detonating cord booster or detonating cord, to the assembly. This is in order to prevent accidental separation or, in the case of electric detonators, accidental violent pulling of the electric wires through the end plug. Thus, the end-caps 46 may be provided with one or more projections 57 in the form of a hoop or hook to which detonating cord or detonator leads may be secured.

[0082] Thus disruptor 40 is based around a structure having two or more end-cap portions in line, with adjacent end-cap portions having an intervening web portion. In this way, there may be provided strips of end-caps (e.g. each strip having six end-caps in line with intervening web portions) which can be separated into single end-caps, pairs or whatever by cutting through web portions as appropriate. The end-caps are used to hold together all the other elements of the structure in a disruptor, namely the former, the box parts, the top and the explosives.

[0083] The strip of end-caps constitute a line of end-caps with intervening webs; the end-caps may be of shapes other than square or rectangular e.g. triangular (whether in identical orientations or in alternating opposite orientations), or hexagonal. The end-caps may be in two-dimensional blocks rather in one-dimensional lines, e.g. to provide a curved arrangement after selective cutting out of some end caps.

[0084] The intervening web between adjacent end-cap portions may be rigid and/or solid. Alternatively, the web may be flexible and/or expandable.

[0085] In one embodiment, the disruptor comprises units in a parallel array in a concave or a convex plane in order to concentrate, or focus the disruptive forces or, conversely, to generate a divergent mass of projectile material.

[0086] The end-caps may employ flexible means of attachment. Interconnection, for example, by blocks of flexible plastic or rubber foam enable an array to be flexed into a curved (convex or concave) configuration. When the material is stiff but crushable (as with paper or thin plastic honeycomb), then the hinge is made deformable but inelastic, thus facilitating rapid adjustment. The end-cap may have an expandable web.

[0087] FIG. 13 shows an alternative means of providing an adjustable means of inter-connection between end-caps in order to allow variable convergence or divergence of adjacent components of an array. A circular and rotatable turret-like insert 60 is passed through a hole 61 in the end-cap 46 and is constrained in that position by an integral external lip 62. The ability of insert 60 to rotate after insertion in the end-cap 46 may be prevented by the teeth 63 on the periphery of the lip 62 which engage in any of a multiplicity of possible positions in the teeth 63 surrounding the hole 61 on the inside of the end-cap 46. The insert 60 has a transverse hole 61 which may conveniently be rectangular. Insertion of a rigid rectangular sectioned lath 64 through the holes 61 in an array of interlocked end-caps 46 stiffens the assembly and provides a means of grasping and manipulating the array by remote means.

[0088] By rotating the inserts 60 in the end-caps 46 of two or more casings 41, an array 70 may be assembled by passing a pair of laths 64 through the holes 61 in the inserts 60 in which the individual charges project the matter contained within enclosures 41 in a convergent or a divergent manner, thereby to suitably direct or spread the effect of the disrupter as appropriate.

Claims

1. A device for generating a liquid jet, the device comprising an enclosure containing a plurality of formers, each defining a concave cavity partially enclosed by the former, each of the formers supporting an explosive charge, and a filler material adjacent the charge within the cavity, the filler material being a liquid, a gel or a non-metallic solid that will liquefy upon detonation of the device.

2. A device for generating a liquid jet, the device comprising an enclosure containing a former with a plurality of concave cavities each partially enclosed and supporting an explosive charge, and a filler material adjacent the charge within each cavity, the filler material being a liquid, a gel or a non-metallic solid that will liquefy upon detonation of the device.

3. A device for generating a liquid jet, the device comprising an enclosure containing at least one former defining a cavity partially enclosed by the former supporting an explosive charge and a filler material adjacent the charge within the cavity, wherein the filler material is a decontaminant.

4. A device according to claim 3 wherein the decontaminant comprises sodium hypochlorite.

5. A device according claim 3, wherein the filler material is pressed or melt-cast solid material.

6. A device according to claim 4, wherein the filler material is disodium hydrogen phosphate dodecahydrate.

7. A device according to claim 5 wherein the filler material is sodium bicarbonate.

8. A device according to claim 1 wherein the filler material is contained in a flexible bag.

9. A device according to claim 8 wherein the or each explosive charge, former and bag are placed within the enclosure, the explosive charge and its former being placed within the bag.

10. A device according to claim 8 wherein the explosive charge, the former and the bag are placed within an outer enclosure, the explosive charge and its former being placed within a fold of the bag.

11. A device according to claim 8 comprising an outer case within which are positioned the explosive charge, the former, the bag within the cavity and a second bag containing filler material positioned at the opposite side of the former to the cavity, within the outer enclosure.

12. A device according to any one claims 8 to 11 wherein the former is a part cylindrical or semi-cylindrical former and the explosive charge is applied to one or more of the inner and outer surfaces of the former.

13. A device according to claim 12 wherein the explosive charge is a detonating cord secured to the surface or surfaces.

14. A device according to claim 13 wherein crenations are provided at opposite ends of the former and the detonating cord is passed longitudinally to and for through notches and round projections of the crenations at each end.

15. A device according to claims 12 or 13 wherein the detonating cord is also passed along the inside of the former.

16. A device according to claim 14 wherein the notches between some of the projections are left empty, thereby using less detonating cord thus providing lighter loads.

17. A device according to any one or more of claims 1 to 9 wherein the explosive charge is sheet explosive stuck by an adhesive or double-sided sticky tape to the former.

18. A device according to any of the preceding claims wherein the or each flexible bag is contained within an outer container and filled through nozzles projecting from the container.

19. A device according to any of the preceding claims wherein the formers and/or an outer enclosure comprise different filler materials.

20. A device for generating a liquid jet, the device comprising an enclosure containing a former with a plurality of cavities each partially enclosed and supporting an explosive charge, and at least one end-cap to hold the former within the enclosure.

21. A device according to claim 20 comprising at least one former supporting an explosive charge; and two end-caps each having a recess to engage with the former thereby securing the former(s) within the enclosure.

22. A device according to claim 21 wherein an end-cap comprises a web which separates two portions of the end-cap, each portion securing a former within the enclosure.

23. A device according to claim 22 wherein the end-cap comprises a plurality of portions, each portion holding a former and a plurality of webs each separating two portions of the end-cap.

24. A device according to any of claims 21 to 23 comprising two end-caps, one at each opposite end of the enclosure and the end-caps holding the former(s) therebetween.

25. A device according to any of claims 20 to 24 wherein an end-cap comprises a peripheral wall(s) to position and constrain the former and one or more walls of the enclosure to thereby hold them in the enclosure.

26. A device according to any of claims 20 to 25 wherein the end-cap and former/wall(s) of the enclosure have co-operating projections/cavities for engagement therebetween.

27. A device according to any of claims 20 to 25 wherein the end-cap comprises an internal wall with an ablated corner shape.

28. A device according to any of claims 20 to 27 wherein an end-cap comprises means to interlock with another end-cap.

29. An array of devices at least one of which as claimed in any of claims 20 to 28, wherein the devices are in a single plane.

30. An array of devices at least one of which as claimed in any of claims 20 to 28 wherein the devices are in a divergent array.

31. An array of devices at least one of which as claimed in any of claims 20 to 28, wherein the devices are in a convergent array.

32. An end-cap for use with a device according to any of claims 20 to 28.