WO2022090160A1

WO2022090160A1 - Unexploded ordnance disposal method and system

Info

Publication number: WO2022090160A1
Application number: PCT/EP2021/079547
Authority: WO
Inventors: Adrian DANN; H. J. A. Van De Vleuten
Original assignee: UXO Control B.V
Priority date: 2020-10-27
Filing date: 2021-10-25
Publication date: 2022-05-05
Also published as: GB202017072D0

Abstract

The present invention relates to the disposal/neutralisation of unexploded ordnance, for example leftover mines or bombs that have failed to detonate. More particularly, the present invention relates to a method of disposal/neutralisation of said ordnance by disruption and disintegration that reduces the likelihood of unintended detonation/deflagration of the ordnance during disposal/neutralisation. Aspects and/or embodiments seek to provide an apparatus, system and method for the controlled disposal of unexploded ordnance in a way that substantially reduces or prevents unwanted high order explosive events during the disposal process.

Description

UNEXPLODED ORDNANCE DISPOSAL METHOD AND SYSTEM

Field

The present invention relates to the disposal/neutralisation of unexploded ordnance, for example leftover mines or bombs that have failed to detonate. More particularly, the present invention relates to a method of disposal/neutralisation of said ordnance by disruption and disintegration that reduces the likelihood of unintended detonation/deflagration of the ordnance during disposal/neutralisation.

Various techniques exist for the disposal of unexploded ordnance, depending on the situation of the ordnance that needs to be neutralised. Ordnance can be found in a variety of locations and in conditions that range from being in full working order to being seriously compromised by degradation (for example via the ingress of water into a corroded casing).

When disposing of unexploded ordnance at sea, and for example where the ordnance is located away from coastal dwellings, shipping lanes and other objects, flora, fauna and personnel, it may be deemed appropriate to use a “high order” or “high order detonation” disposal technique. A “high order detonation” technique is a method that causes controlled detonation (i.e. to prevent unacceptable detonation, that for example would damage shipping or cause injury or death) of the unexploded ordnance in order to render it safe, where the explosive event produces a blast pressure front that moves rapidly and shatters any objects in its path. Such a detonation in effect triggers the ordnance to detonate by either triggering it in the way it was designed (e.g. triggering a sensor or mechanism that results in the ordnance exploding) or by causing the explosive material to react and detonate (e.g. by planting another explosive beside or on the unexploded ordnance and causing to detonate which in turn causes the unexploded ordnance to detonate).

Referring to Figure 1 , a typical high order detonation using a high concentration blast of molten metal(s) 100 is shown and will now be described in more detail.

The high order disposal system 104 is positioned in close proximity to the unexploded device 101 that has been targeted for disposal, for example a bomb that had previously been dropped from an aircraft and which had failed to detonate on landing in the ocean and so had sunk to the sea bed. The unexploded device 101 is made up of a casing containing at least an initiator/detonator 103 and an explosive charge body 102. In normal operation, the unexploded device 101 would trigger the primary energetic (i.e. the explosive material) in the initiator/detonator 103 based on some causation (e.g. a timer, or a movement/electromagnetic sensor) which in turn causes the detonation of the explosive charge body 102. The disposal system 104 produces a concentrated stream of molten material or a plasma jet/bullet 105 which engages with the casing of the unexploded device 101. The molten material/plasma jet 105 causes the casing to melt, thereby penetrating the casing and allowing the molten material/plasma jet 105 to enter the body of the unexploded device 101 , engage with the explosive charge body composition 102 and neutralise the ordnance 101.

Referring now to Figure 1A, an alternative typical high order detonation using a blast fragmentation event 100a is presented and will now be described in more detail.

A high order disposal system 104a is attached to or located in close proximity to an explosive device/target 101. The unexploded device 101 is made up of a casing containing at least an initiator/detonator 103 and an explosive charge body 102. In normal operation, the unexploded device 101 would trigger the initiator/detonator 103 based on some causation (e.g. a timer, or a movement/electromagnetic sensor) which in turn causes the detonation of the explosive charge body 102. The high order disposal system 104a is itself an explosive charge that is triggered remotely and causes the initiator/detonator 103 and/or the explosive charge body 102 to detonate thus causing the explosive device 101 to detonate in a controlled fashion (i.e. on remote triggering, once objects and personnel to which a detonation would pose a risk had been moved outside of and away from the blast radius of the detonating explosive device 101).

Triggering a high order detonation event has been and currently is the preferred disposal technique in most cases providing that environmental mitigation measures are taken to reduce the effects of blast and shock waves inducing damage and trauma due to the proximity to flora, fauna, shipping or personnel and the resulting risk of damage thereto and/or the risk of pollution/contamination of the neighbouring environment.

As a result, “low order” techniques that potentially cause significantly smaller detonation events (provided that the intended technique is successful) are perhaps preferred to “high order” techniques in situations when disposing of unexploded ordnance, might avoid the consequences of a large explosion and the disruption of moving objects and personnel away from the blast radius of a large explosion in advance of a controlled detonation. Such “low order” techniques can produce a lower impact on the environment and a smaller shock wave in the water thus the impact on the seabed and in the surrounding environment is minimised.

An example “low order” technique is the military approved procedure 200 developed over many years and which is taught in both theory and practice to advanced explosive ordnance disposal operators at the Defence Ordnance Disposal School (DEODS) as well as at some private training organisations, and which is shown in Figure 2. This technique will now be described in more detail. This typical low order deflagration initiation using a small high temperature plasma jet technique 200 is one that can be used by explosive ordnance disposal (EOD) operators in an attempt to lessen the resultant effect of blast and shock-wave (resulting in blast/ shock-wave, vibrational and acoustic disturbances) and to reduce potential collateral damage to adjacent infrastructure and hazards when controlled disposal on an explosive device/target 101 where a “high order” detonation is unacceptable.

It is however well understood, and part of the procedures and preparations, that a “low order” result cannot be guaranteed as it carries a 10% - 20% chance of failure and that a “high order” event may well result when a “low order” technique is attempted.

The technique 200 uses a low order disposal system 201 placed in close proximity to the unexploded device 101. The unexploded device 101 is made up of a casing containing at least an initiator/detonator 103 and an explosive charge body 102. In normal operation, the unexploded device 101 would trigger the initiator/primer/detonator 103 based on some causation (e.g. a timer, or a movement/electromagnetic sensor) which in turn causes the detonation of the explosive charge body 102. The low order disposal system 201 may be placed above, next to (at a variety of orientations), or attached to, the target 101 using optional attachment means 202.

The disposal system 201 uses a copper/magnesium (or similar single- or dualcombination) metallic “liner” to form a very high-temperature plasma jet 205, which is introduced into the device by compromising the casing 101 and eventually into the main explosive charge body 102 of the target 101 to initiate a “burn” 206 as shown 200a in Figure 2A by melting a hole 203 in the casing of the explosive device 101 in order to penetrate the casing.

As shown 200b in Figure 2B, the “burn” 206 (which excites the explosive charge body 102 to generate heat and pressure) develops very rapidly, resulting in the explosive filling 102 creating increased pressure and heat within the casing of the explosive device 101 , which should rupture or burst 208 the casing of the explosive device 101 as shown in Figure 2C. This critical part of the process may result in a “deflagration” of the explosive filling 102 in part or in its entirety (i.e. generates a partial energetic reaction of the explosive charge body 102). As a result, following deflagration an innocuous reaction producing a low level detonation of only the remaining un-deflagrated portion of the explosive charge body 102 should occur, which is significantly smaller in magnitude compared to an equivalent “high order” detonation, hence the use of the term “low order” to describe this technique.

However, if the internal “burn” creates a rate of burn which generates heat and pressure which does not rupture the casing sufficiently quickly, the reaction can turn from deflagration to detonation, and a “high order” detonation occurs. As mentioned previously, this occurs approximately 10% - 20% of the time when attempting a “low order” detonation and requires “low order” disposal operations to take all of the precautions required when performing a “high order” disposal due to the non-trivial risk of a “high order” detonation occurring.

Summary of Invention

Aspects and/or embodiments seek to provide an apparatus, system and method for the controlled disposal of unexploded ordnance in a way that substantially reduces or prevents unwanted high order explosive events during the disposal process.

According to a first aspect, there is provided a canister for neutralising an unexploded ordnance, wherein the unexploded ordnance comprises an ordnance casing and an explosive content within the ordnance casing, comprising: a substantially tapered cylindrical canister casing having a first and second end; a cap at the first end of the tapered cylindrical canister casing, the cap operable to be positioned against the ordnance casing; a spacer arrangement abutting the cap, the spacer arrangement located within the tapered cylindrical canister casing; a cap at the second end of the tapered cylindrical canister casing; an explosive charge at substantially a second end of the tapered cylindrical canister casing; and wherein the tapered cylindrical canister casing is operable to be filled with liquid and wherein the explosive charge is operable to cause the liquid within the tapered cylindrical canister casing to be forced out of the first end of the tapered cylindrical canister casing along with at least a portion of the cap at the first end of the tapered cylindrical canister casing towards the ordnance casing, compromise the same, and enter into the explosive content within the ordnance body.

Using an explosive-generated jet of water to penetrate the casing of an unexploded ordnance can allow for the explosive content of the unexploded ordnance to be disrupted and disintegrated without triggering the explosive content to cause unwanted/unexpected deflagration or detonation.

Optionally, the canister further comprises a liner within the tapered cylindrical canister casing, the liner formed substantially conically and wherein the explosive charge is operable to cause the liquid within the tapered cylindrical canister casing to be forced out of the first end of the tapered cylindrical canister casing along with the liner and at least a portion of the cap at the first end of the tapered cylindrical canister casing towards the ordnance casing and into the explosive content within the ordnance casing. Optionally the liner abuts the spacer arrangement.

Providing a liner within the canister can increase the effectiveness of penetration of the ordnance casing.

Optionally, the liner comprises a non-metallic material. Using a non-metallic material as the liner can eliminate the risk of deflagration or detonation of the ordnance explosive content.

Optionally, either or both of the cap at the first end of the tapered cylindrical canister casing and the cap at the second end of the tapered cylindrical canister casing are removable.

Allowing either or both caps of the canister to be removable can increase the ease of use of the canister.

According to another aspect, there is provided a method for neutralising an unexploded ordnance, wherein the unexploded ordnance comprises an ordnance casing and an explosive content within the ordnance casing, comprising the steps of: generating one or more jets of liquid that penetrate the ordnance casing, the jets of liquid operable to disrupt and disintegrate the explosive content within the ordnance casing after penetrating the ordnance casing.

Using a jet of liquid to penetrate the casing of an unexploded ordnance can allow for the explosive content of the unexploded ordnance to be disrupted disintegrated without triggering the explosive content to cause unwanted deflagration or detonation.

Optionally, generating one or more jets of liquid comprises generating at least two jets of liquid.

Using two or more liquid jets to penetrate the casing of an unexploded ordnance can allow for the explosive contents of the unexploded ordnance to be removed from within the casing or rendered safe and neutralised using the liquid that is injected by the liquid jets into the casing.

Optionally, each of the jets of liquid is generated simultaneously.

Generating simultaneous liquid jets can allow more comprehensive disruption of the explosive material within the unexploded ordnance.

Optionally, the jets of liquid are operable to penetrate the ordnance casing at substantially opposing ends of the ordnance casing.

Positioning the liquid jets at substantially opposing ends of the unexploded ordnance can allow for an increased amount of the explosive material within the casing to be disrupted and disintegrated by the liquid jets.

Optionally, each of the jets of liquid are operable to penetrate the ordnance casing along an axis offset from each other.

Offsetting the jets of liquid can allow for more comprehensive disruption and/or disintegration of the explosive content of the unexploded ordnance.

Optionally, the unexploded ordnance is located substantially underwater. Optionally, the jets of liquid comprise jets of water, optionally wherein the jets of water comprise jets of high-pressure water.

When disposing of unexploded ordnance that is located underwater, it can be efficient to use water in the liquid jets due to the prevalence of water around the unexploded ordnance. Using water for the jets of liquid can allow the use of a readily available resource that is unlikely to trigger deflagration or detonation of the ordnance.

Optionally, there is additionally performed the step of using a cover to contain the unexploded ordnance, optionally wherein the cover is also operable to contain one or more containers each operable to generate the jets of liquid.

Providing a cover to contain the unexploded ordnance, and optionally the liquid jet devices too, can increase the likelihood of being able to localise and make easier to recover and remove the explosive material once it has been disintegrated and evacuated from within the casing of the unexploded ordnance as it will be contained within the cover and able to be removed from within the casing to prevent environmental damage through it dispersing in the surroundings of the unexploded ordnance. Optionally the cover can comprise a dome completely covering the apparatus. Alternatively, the cover can comprise a ring that surround the base of the apparatus. The cover or ring embodiments can reduce the dispersion of the disrupted explosive content and/or reduce the time needed for cleaning the seabed following neutralisation of the ordnance.

Optionally, an explosive charge is used to initiate the jets of liquid.

By initialising the liquid jets using an explosive charge, the liquid jets can more effectively penetrate the casing of the unexploded ordnance without using explosive charges directly to pierce the casing of the unexploded ordnance (as this can be more likely to trigger a high order detonation of the unexploded ordnance). Optionally, the explosive charge causes the liquid jet to initiate at a speed of 8,000 metres per second.

Optionally, the jets of liquid are controlled remotely, optionally using non-electric shock-tube firing chain initiated by manual or remote means (for example, secure/coded RF transmitter/receiver).

By operating the apparatus remotely, personnel and support vessels can be kept at a safe distance from the unexploded ordnance thereby reducing the risk of injury or fatality when disposing of unexploded ordnance using the apparatus.

According to another aspect, there is provided a system for neutralising an unexploded ordnance, wherein the unexploded ordnance comprises an ordnance casing and an explosive content within the ordnance casing, comprising: one or more tapered canisters, each tapered canister operable to generate a jet of liquid for penetrating the ordnance casing. Brief of

Embodiments will now be described, by way of example only and with reference to the accompanying drawings having like-reference numerals, in which:

Figure 1 shows a typical “high order” detonation using a high-concentration blast of molten metals;

Figure 1A shows a typical “high order” detonation using a blast fragmentation event;

Figure 2 shows a typical “low order” detonation process initiation using a high temperature plasma jet;

Figure 2A shows a typical “low order” detonation process where plasma penetrates the target casing;

Figure 2B shows a typical “low order” detonation process creating an internal burn in the target;

Figure 2C shows a typical “low order” detonation process completed by bursting the target casing;

Figure 3 shows a detailed view of a “low yield” canister for a “low yield” target neutralisation system with an exploded view for the first end and second end of the canister according to an embodiment;

Figure 3A shows a “low yield” target neuralisation system according to an embodiment;

Figure 3B shows the “low yield” target neutralisation system penetrating the target device casing with a non-explosive water-based jet according to an embodiment;

Figure 3C shows the “low yield” target neutralisation system neutralising components of the target device casing with the water-based jet and generating a pressure wave within the casing according to an embodiment;

Figure 3D shows an alternate configuration of the “low yield” target neutralisation system for larger target devices according to an embodiment;

Figure 3E shows an alternate configuration of the “low yield” target neutralisation system according to an embodiment;

Figure 4 shows a “low yield” target neutralisation system with a cover according to an embodiment; and

Figure 4A shows a “low yield” target neutralisation system with an alternate cover according to an embodiment.

Because of the potential uncertainty and somewhat unpredictable results when relying on existing “low order” tools and techniques, the aspects and/or embodiments presented below were developed with the aim to be able to substantially guarantee a “high order” explosion not to occur and the approach has been generally labelled as a “low yield” technique.

The embodiments described can be used in a similar way to which “high order” and/or “low order” detonations are usually planned and can use proven remote initiation systems to control the process.

Referring to Figures 3 to 4A, example embodiments will now be described in more detail in the following specific description.

Referring initially to Figure 3, a detailed view of a “low yield” canister for a “low yield” target neutralisation system 300 according to an embodiment is shown and will now be described in more detail.

The canister 301 comprises a tapered cylinder casing (or barrel) having a cap 310, an internal spacer 320, an internal liner 330, an explosive 350 and a detonator 340. Not shown in Figure 3 is another cap, the “end cap”, at the other end of the canister 301 that is used to fix the explosive 350 and detonator 340 in place. Optionally, a device can be used to hold the explosive charge 350 in place. In preferred embodiments, the canister provides a choked barrel to help achieve a high-pressure output. In some embodiments, the shape of the barrel may be substantially cylindrical.

The cap 310 is removable and is formed in this embodiment with a screw thread to mate with a screw thread on the canister 301 allowing the cap 310 to be fastened to the end of the canister 301. Optionally a canister seal 340 can be included to seal the cap 310. In alternative embodiments, the cap can be formed as part of the canister 301 or attached non- removably to the canister 301.

The spacer 320 in this embodiment holds the liner 330 a spacing distance of 120mm away from the cap 310 and with liner 300, the spacing distance between the casing of the target device and the start of the generated high-pressure jet is approximately 300mm. This allows the canister 301 to be placed with the cap 310 abutting the unexploded ordnance, and therefore the liner 330 is held the spacing distance away from the casing of the unexploded ordnance to ensure the generated high-pressured jet reaches its optimal pressure and size before engaging with the target device 101 .

In use, the canister 301 is filled with liquid, and in this embodiment is filled with water. Optionally the water can be sea water or in some cases distilled water to prevent gas being present in the distilled water to allow for post-disposal forensics to be carried out more accurately. If no optional canister seal 340 is used and the canister is used for underwater disposal operations, then the canister 301 will fill with sea water. If the canister is used for land-based disposal operations, then the optional canister seal 340 will prevent the water in the canister from leaking out. The optional canister seal 340 can be a double O-ring seal. The explosive charge 350 is preferably held and optionally shaped in a way that it emits a shock wave/blast along the central axis of the barrel of the canister 301 towards the point of the internal liner 330. In this embodiment, approximately 750g of high explosive is used as the explosive 350. Optionally, a conical charge shaper (not shown) can be fitted either to the end cap (not shown) or held in place between the end cap (not shown) and the point of the conical internal liner 330. The end cap can be removable and use a screw thread as with the cap 310. The detonator 340 can be fitted to either side of the end cap and the explosive on the inside of the end cap and inside the canister 301 .

In operation, the canister 301 is filled with water and placed with the cap 310 abutting the unexploded ordnance to be neutralised. Then, the detonator 340 is triggered remotely, preferably using a non-explosive trigger, and causes the primary energetic/explosive 350 to fire. The explosive 350 once fired first causes the internal liner to invert, pushing the cone into a mirror image shape as the shock wave from the explosive 350 initially reaches the point of the conical liner 330 and finally reaches the lower ring of the liner 330. The liner 330 and the water filling the canister 301 move away from the explosive 350 within the canister and are pushed out of the end of the canister 301 along with fragments of the cap 310 and into the casing of the unexploded ordnance located abutting the cap 310 at a speed of approximately 8,000 metres per second. In this way, the canister generates a high pressured jet by forcing out the water within the canister 301 as well as fragments of the liner 330 and/or the cap 310 in order to penetrate, with accuracy, the often thick walls of unexploded ordnance devices. In some embodiments, the liner 330 will collapse upon detonation of the explosive 350 and the mass of the collapse or fragmented liner will combine with the water to provide a more precisive penetrative force when the jet reaches the unexploded ordnance device. As a result, the canister does not inject a molten projectile in the target device 101 that would cause deflagration or detonation but instead disrupts and disintegrates substantially all internal components of the target device and its main explosive filling 101. This ensures a guaranteed low yield neutralisation of the target device 101 without substantial disruption to the environment nor harming any surrounding sea-life.

In some embodiments, the pressure of the resulting output from the canister 301 can be adjusted by changing the dimensions of the canister and the net explosive content (NEQ) “load” 301. In this way, a canister 301 (with tapered barrel) with a specific pressure can be manufactured for a given need.

Referring next to the embodiment shown in Figure 3A, an embodiment of a low yield target neutralisation system 300a will now be described in more detail below.

The low yield target neutralisation system 300 shown in Figure 3A comprises a low yield disposal system 301 positioned near or around an explosive device/target 101. The unexploded device 101 is typically made up of a casing containing at least an initiator/detonator and an explosive charge body 102. In some embodiments, the initiator/detonator of the unexploded ordnance 101 may be positioned at the nose, tail or transvers of the device 101. Although a “shaped charge” is depicted in the figures, embodiments of this application can be used with any type of explosive ordnance, for example, bombs, ground mines, buoyant mines, etc. In normal operation, the unexploded device 101 would trigger the initiator/detonator based on some causation (e.g. a timer, or a movement/electromagnetic sensor) which in turn causes the detonation of the explosive charge body 102.

The low yield disposal system 300a comprises a first low yield canister 301 and a second low yield canister 301a positioned facing two target locations of the unexploded ordnance 101. Preferably, the two target locations are chosen to offset an axis so as not to negate the substantially linear force generated the by a corresponding low yield canister. The first 301 and second low yield canisters 301a generate a first high-pressure water-based jet 305 and a second high-pressure water-based jet 305a, respectively. In some embodiments, the two canisters can be positioned at two opposite sides of the unexploded ordnance 101 and secured in place, either to the target device 101 or a substantially stable surface such as a seabed with the optional attachment means 302. Alternatively, rather than using optional attachment means 302, other positioning means to hold the canisters 301 , 301a in place can be used. Further alternatively, the canisters 301 , 301a may be positioned in different places relative to the explosive device 101 to target weak points of the unexploded ordnance 101 or strategically positioned to neutralise any mechanical or electronic components, or any type of initiator/detonator 103 components to reduce, or eliminate, the likelihood of a high order detonation.

Referring now to Figures 3B and 3C, the embodiment shown in Figure 3 will now be described during operation in more detail below.

In Figure 3B, the low yield target neutralisation system penetrating the casing of the target 101 with non-explosive water-based jets 300b is shown. In some embodiments, the user may implement the same or similar apparatus’ and techniques used in high order detonations, however, upon piercing the casing of the target with a non-explosive liquid such as water, the explosive charge body does not react to the external substance and thus will not detonate the device.

The low yield disposal system 301 causes the first high-pressure water-based jet 305 to enter the casing 306 at a first location on the casing 303 and causes the second high- pressure water-based jet to enter the casing 306a at a second location on the casing 304.

In this embodiment two high-pressure water-based jets, in contrast to the high- temperature plasma jet of the prior art, are used to achieve the penetration and selective disruption of the explosive material in the unexploded ordnance, and this can reduce the risk of unwanted and perhaps unexpected “high order” detonation.

To increase the likelihood of penetrating the casing of the target 101 , an explosive (a primary energetic as described with reference to Figure 3) is used to initiate the canisters 301 , 301a at a sufficiently high energy to produce high-pressure liquid jet which is capable of piercing the casing of the target device 101 without being compromised by the environmental surroundings of the target device 101. For example, the high-pressured water-based jets remain unaffected by the ocean water, sand bed, debris, etc., which may be engulfing the target device 101. In the preferred embodiment of the canisters 301 , 301a abutting the target device, the aforementioned problem is alleviated due to the spacing means 320 implemented within the canisters 301 , 301a. In comparison to existing low-order techniques, a much- reduced mass of primary energetic is used (in this embodiment 2 x 750 g charges) as opposed to the prior art, where typically 2.5 kg or 5 kg of primary energetic material is used for systems configured for shaped charges or blast fragmentation charges respectively. The result of the use of the primary energetic to initiate the water-based jets is that instead of either a plasma jet forming, if configured as a shaped charge, or a very violent explosion occurring adjacent to the target 101 if configured as a blast fragmentation charge, a very powerful, precise and penetrative disruptive but explosive free “hyper” water-based jet is generated when the canisters 301 , 301a are initiated.

When initiated, the small quantity of primary energetic in each canister (750 g) forces the water from the flooded barrel of the canister 301 , 301a, together with any fragments components of the canister 301 , 301a, at a very high speed and pressure, forming a concentrated and very powerful “jet” of water which will easily penetrate the casings of the target 101 (for example, including by not limited to bombs, torpedoes, ground mines, moored- mine shells/charge cases, missiles, depth-charges, naval shells) with the intention to disrupt any arming mechanisms and disintegrate the primary energetic explosive filling 102 before the explosive molecules can react. In embodiments, the canisters 301 , 301a are initiated substantially simultaneously to generate multiple high-pressured water-based jets to the target device 101 at substantially the same time.

In Figure 3C, the low yield target neutralisation system neutralising the internal components of the target device 101 with the water-based jets and generating a pressure wave 300c is shown and will now be described in more detail.

The high-pressured water-based jets have now pierced the casing at both the first location 303 and the second location 304 and the casing has now been filled with water 307 and a pressure wave 308 has been created within the target device 101. The pressure wave 308, in combination with the powerful water-based jets, assists in the disintegration of the explosive material (e.g. the primary energetic in the explosive device/target 101) which has often been compromised by the deterioration and loss of water-tight integrity of its casing. Even if the explosive material (i.e. the explosive energetic contents) of the target 101 has not been compromised by water contamination, the method of this embodiment substantially results in disintegration and disruption as opposed to a high order detonation or deflagration because the water-based jets, the pressure wave and because the barrel of the cannisters 301 , 301a are flooded prior to use, no explosive is used directly on the target 101 (nor is a plasma jet formed) which would induce a detonation.

Due to the pressure caused within the casing of the target device 101 , the exit wounds 309, 309a of the first and second high pressure water-based jets are often significantly larger than the ingress wounds 303, 304.

Any arisings (i.e. the parts, components, elements of the target 101 which remain on completion of the disruption by the use of the canisters), which could contain small amounts of primary energetic such as primer tubes, can be safely recovered, wet-stored and disposed of safely and in an environmentally safe manner at specialized disposal facilities.

As a result of the process of this embodiment, the casing of the target 101 will rupture and/or split and the primary energetic contents 102 will disintegrate into either thousands of tiny pieces of material, which is harmless in water and will dissipate completely over a short period of time (a few months) and/or production of an “emulsion” and tiny fragments of energetic, which forms an “emulsion” I “cloud” and will dissipate almost immediately. Thus, this low yield system also enables a more efficient and environmentally friendlier method of cleaning up the seabed or the surrounding area where the target device may have been found.

Due to the precise and efficient nature of this low yield system, from surveying the surrounding area, neutralising the target device and cleaning any arisings, the system and method provides a more cost-effective solution. As an example, the guaranteed nature of the low yield system removes the need for one or often multiple bubble curtains to be deployed around the target device which is an expensive device.

As shown in the Figure 3D, in other embodiments more than two canisters 301 , 301a, 301 b, 301c generating additional water-based jets may be used as part of the low yield system to safely neutralise a larger unexploded ordnance 101. In some embodiments, when presented with a large (volume) unexploded ordnance 101 the low yield system may require four to eight canisters that are all offset from each other and initiated simultaneously.

In Figure 3D, an embodiment is shown whereby it differs from that of Figures 3 to 3C by positioning the first and second low yield canisters 301 , 301a in an alternative configuration by moving the first and second low yield canisters 301 , 301a to a different position relative to the explosive device/target 101 thus causing the casing of the explosive device 101 to be pierced in different places depending on the needs of the neutralisation of the target device 101. Referring now to Figure 4, an embodiment of a low yield target neutralisation system with a cover 400 will now be described in more detail.

In this embodiment, the first and second low yield canisters 301 , 301a are positioned at opposing positions of an explosive device/target 101 , either side of the main body of the target 101. As with the previous example embodiment of Figures 3A to 3C, the canisters 301 , 301a generate waterjets that pierce the casing at two points 303, 304 and cause the casing to fill with water 307 and create a pressure wave 308 thus neutralising the explosive device 101. In addition, in this embodiment, a dome shaped cover for the low yield disposal system 401 is provided to encapsulate the low yield system and capture the disintegrated contents of the canisters 301 , 301a and/or arisings or emulsion from the target device within the dome shaped cover 401 for safe removal and disposal using for example tubes connected to the casing to evacuate the primary energetic contents in order to prevent their dispersal into the neighbouring environment. Optionally, the cover 401 rests on the seabed 402 or any other substantially stable surface surrounding the target device 101.

Referring now to Figure 4A, an embodiment of a low yield target neutralisation system with a cover in an alternative configuration 400a will now be described in more detail.

Similar to the embodiment described in relation to Figure 4, this embodiment differs from that of Figure 4 by using an open top ring-shaped cover 401a. In this embodiment, the disintegrated contents of the canisters 301 , 301a and/or arisings or emulsion from the target device is encapsulated within the ring shaped cover 401a and is then easily retrievable via the open top using any known retrieving methods/robots.

The covers 401 , 401a depicted in Figure 4 and 4A are only possible due to the low yield neutralisation process mentioned herein. The purpose of the covers 401 , 401a is to prevent the spread of the explosive fill or any debris following the completion of the neutralisation process.

Any system features as described herein may also be provided as a method feature, and vice versa. As used herein, means plus function features may be expressed alternatively in terms of their corresponding structure.

Any feature in one aspect may be applied to other aspects, in any appropriate combination. In particular, method aspects may be applied to system aspects, and vice versa. Furthermore, any, some and/or all features in one aspect can be applied to any, some and/or all features in any other aspect, in any appropriate combination.

It should also be appreciated that particular combinations of the various features described and defined in any aspects can be implemented and/or supplied and/or used independently.

Claims

CLAIMS:

1 . A canister for neutralising an unexploded ordnance, wherein the unexploded ordnance comprises an ordnance casing and an explosive content within the ordnance casing, comprising: a substantially tapered cylindrical canister casing having a first and second end; a cap at the first end of the tapered cylindrical canister casing, the cap operable to be positioned against the ordnance casing; a spacer arrangement abutting the cap, the spacer arrangement located within the tapered cylindrical canister casing; a cap at the second end of the tapered canister casing; an explosive charge at substantially a second end of the tapered cylindrical canister casing; and wherein the tapered cylindrical canister casing is operable to be filled with liquid and wherein the explosive charge is operable to cause the liquid within the tapered cylindrical canister casing to be forced out of the first end of the tapered cylindrical canister casing along with at least a portion of the cap at the first end of the tapered cylindrical canister casing towards the ordnance casing and into the explosive content within the ordnance casing.

2. The canister of claim 1 further comprising a liner within the tapered cylindrical canister casing, the liner formed substantially conically and wherein the explosive charge is operable to cause the liquid within the tapered cylindrical canister casing to be forced out of the first end of the tapered cylindrical canister casing along with the liner and at least a portion of the cap at the first end of the tapered cylindrical canister casing towards the ordnance casing and into the explosive content within the ordnance casing.

3. The canister of any preceding claim, wherein the liner abuts the spacer arrangement.

4. The canister of any preceding claim, wherein the liner comprises a non-metallic material.

5. The canister of any preceding claim wherein either or both of the cap at the first end of the tapered cylindrical canister casing and the cap at the second end of the tapered cylindrical canister casing are removable.

6. A method for neutralising an unexploded ordnance, wherein the unexploded ordnance comprises an ordnance casing and an explosive content within the ordnance casing, comprising the steps of: generating one or more jets of liquid that penetrate the ordnance casing, the jets of liquid operable to disrupt the explosive content within the ordnance casing after penetrating the ordnance casing.

7. The method of claim 6 wherein generating one or more jets of liquid comprises generating at least two jets of liquid.

8. The method of claim 7 wherein each of the jets of liquid is generated simultaneously.

9. The method of any of claims 7 to 8 wherein the jets of liquid are operable to penetrate the ordnance casing at substantially opposing ends of the ordnance casing.

10. The method of any of claims 7 to 9 wherein each of the jets of liquid are operable to penetrate the ordnance casing along an axis offset from each other.

11. The method of any of claims 6 to 10 wherein the unexploded ordnance is located substantially underwater.

12. The method of any of claims 6 to 11 wherein the jets of liquid comprise jets of water, optionally wherein the jets of water comprise jets of high-pressure water.

13. The method of any of claims 6 to 12 further comprising the step of using a cover to contain the unexploded ordnance, optionally wherein the cover is also operable to contain one or more containers each operable to generate the jets of liquid.

14. The method of any of claims 6 to 13 wherein an explosive charge is used to initiate the jets of liquid.

15. The method of any of claims 6 to 14 wherein the jets of liquid are controlled remotely, optionally using non-electric shock-tube firing chain initiated by manual or remote means. A system for neutralising an unexploded ordnance, wherein the unexploded ordnance comprises an ordnance casing and an explosive content within the ordnance casing, comprising: one or more tapered canisters, each tapered canister operable to generate a jet of liquid for penetrating the ordnance casing.

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