U.S. patent application number 10/466942 was filed with the patent office on 2004-06-17 for device for the disruption of explosive objects.
Invention is credited to Alford, Sidney C.
Application Number | 20040112241 10/466942 |
Document ID | / |
Family ID | 32510384 |
Filed Date | 2004-06-17 |
United States Patent
Application |
20040112241 |
Kind Code |
A1 |
Alford, Sidney C |
June 17, 2004 |
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.
Inventors: |
Alford, Sidney C; (Corsham,
Wiltshire, GB) |
Correspondence
Address: |
RYAN KROMHOLZ & MANION, S.C.
POST OFFICE BOX 26618
MILWAUKEE
WI
53226
US
|
Family ID: |
32510384 |
Appl. No.: |
10/466942 |
Filed: |
January 16, 2004 |
PCT Filed: |
January 18, 2002 |
PCT NO: |
PCT/GB02/00242 |
Current U.S.
Class: |
102/364 |
Current CPC
Class: |
F42B 3/08 20130101; G01M
13/022 20130101; F41B 9/0046 20130101 |
Class at
Publication: |
102/364 |
International
Class: |
F42B 012/44 |
Foreign Application Data
Date |
Code |
Application Number |
Jan 19, 2001 |
GB |
0101364.5 |
Dec 12, 2001 |
GB |
0129666.4 |
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.
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.
* * * * *