Defense against hypersonic vehicles by atmospheric dispersal of abrasive material
Patent Information
- Authority / Receiving Office
- WO · WO
- Patent Type
- Applications
- Current Assignee / Owner
- Filing Date
- 2026-02-06
- Publication Date
- 2026-08-13
Smart Images
Figure CA2026050191_13082026_PF_FP_ABST
Abstract
Description
Defense against Hypersonic Vehicles by Atmospheric Dispersal of Abrasive Material
[0001] The present disclosure relates to a general concept consisting primarily as a defensive system designed to disrupt and destroy high velocity vehicles, whether missiles or aircrafts, which will be referred to herein as “incoming threats” or “threats”. It also relates to methods and systems to practically apply this concept.
[0002] The velocity of the incoming threat is referred as “hypersonic”, generally considered as exceeding Mach 5. The invention also relates to the application of the described concept towards vehicles moving at velocities close to hypersonic but below the value mentioned above.
[0003] Defense strategies against ballistic missiles can focus on specific phases of the missile path upon which the defense system intercepts the threat. Concentrating on the boost phase, at which multiple warheads and / or countermeasures have not as yet been deployed, is a strategy that decreases the burden on sensors to distinguish lethal payload from countermeasures (see US patent 7,394,047 B1). However, this requires having missile defense systems deployed relatively close to the launch site and the capability to quickly dispatch an interceptor despite large uncertainties on the nature of the vehicle, its target and more generally the intent of the adversary.
[0004] Intercontinental missiles can also be defeated mid-course, out of the atmosphere (see US patent 8,084,724 B1), or in their terminal phase (see European patent EP 2,955,742 B1). All of these strategies have merits and technical challenges. Interceptors used to defeat warheads in their terminal phase can be based on hard kill, in which the interceptor warhead collides with the incoming threat, or proximity detonation in which the threat is defeated by shrapnel ejected from the interceptor (US patent 7,977,614 B2; Russian patent 2,651,407 C1).
[0005] The defense against cruise missiles is mostly similar to air defense against manned or unmanned aircraft. The missile launch is extremely difficult to detect, and its flight path does not display different phases in which interception strategies are radically different. The overall path is less predictable than a ballistic missile trajectory, but its speed is generally significantly lower. Cruise missiles can be defeated by hard kill or proximity detonation of an interceptor payload, or by directed energy systems (US patents 5,198,607 A, 6,396,577 B1).
[0006] When missiles are moving at a hypersonic velocity, typically in excess of Mach 5, the defense systems reported above for warheads interception in their terminal phase or for cruise missiles are significantly complicated. The use of laser-based systems (whether laser beams directed towards the moving object or the object passing through an array of beams) is not practical since the beam could hardly be focused on such a fast-moving object (or the object surface exposed to a stationary beam) long enough for it to be destroyed, especially since such objects are specifically designed to withstand heat and their body at such speed already behaves as a black-body in terms of light emission and absorption. Physical interceptors, whether related to a direct collision or a proximity detonation, need to come in close proximity to the fast-moving vehicle, which poses many challenges in terms of interceptor guidance. An option describes the use of rockets launched from a carrier guided on a collision course with the hypersonic target (Russian patent 2,777,874 C1), but this requires extremely high accuracy for the guidance systems of both the carrier and its detachable rockets, and offers a very short margin of reactivity. Methods had been proposed to approach the incoming threat from behind (Chinese patent 113,959,268 A; US patent application 2006 / 0000348 A1), therefore reducing the relative speed of the two vehicles, but in the case of hypersonic vehicles this requires interceptors to be hypersonic themselves, and significantly faster than the incoming threat. This would be impractical, especially against high-end strategic warheads.
[0007] The present invention opens the door to a different approach, in which the interception relies on affecting a wide volume of air on the incoming missile path, therefore removing the requirement for a precise encounter (in time and space) and providing the interceptor vehicle with margin in terms of the location and timing of actuation.
[0008] The invention focuses on release of the payload of a missile defense interception platform at least several seconds before the arrival of the incoming threat and affecting a large cross section around its expected path, therefore reducing the need to precisely determine the point of encounter (in time and space) between the threat and the interceptor. The threat destruction capitalizes on the intense conditions to which vehicles moving at hypersonic velocities already face and abruptly exacerbates those conditions to rapidly degrade and disrupt thermal protection features, leading to the destruction of the vehicle itself. The proposed mechanism to trigger such abrupt increase of the degradation of the heat shield is through the abrasive effect of solid refractory material locally and temporarily dispersed in the atmosphere on the most likely expected path of the incoming threat.
[0009] Another advantage of the proposed option is that since the platform does not approach the threat and does not use a proximity radar, it reduces the likelihood of reactive avoidance maneuvers from the incoming missile.
[0010] The aerial dispersal of powdered material can be carried out by means of explosive release from the release vehicle warhead, the in-flight aerodynamic dispersal from the release vehicle, the explosive release by submunitions ejected from one or several carrier vehicles or any other option in which one or several platforms are used to disperse, directly or indirectly, fine grains or small fragments of material in a large volume.
[0011] This material, unlike the payload of most interceptors of more traditional missile defense systems, is chemically inert, which is a significant consideration for the safety of reloading operations especially for a sea-based system.
[0012] A further advantage of the release of material over kinetic interceptors lies in the possibility to reuse the vector, while dispersing a low-cost material, rather than sacrificing costly interceptors for each threat neutralization.
[0013] schematically illustrates an incoming missile, in the upper right corner of the drawing, and its calculated expected trajectory represented by a dashed line and a cone of probability. A so-called “abrasive material release vehicle” used to disperse powdered material on the expected path of the incoming missile is also represented, moving from right to left on a horizontal trajectory mostly perpendicular to the incoming missile direction and at a slightly higher altitude. The dispersed abrasive material released from the “release vehicle” is represented as a cloud on the most likely path of the incoming missile.
[0014] Investigations – Detailed description of operational employment
[0015] The overall interception sequence comprises but is not limited to: (1) Incoming hypersonic threat detection, (2) Calculation of the most likely incoming threat trajectory, (3) launch and guidance of one or several vehicles used to release abrasive material, (4) release of abrasive powdered material on the most likely expected path of the incoming threat, (5) interaction of the abrasive material with the body of the incoming threat, (6) confirmation of incoming threat neutralization.
[0016] The steps between (1) and (3), including the decision-making process to determine the most suitable defense system to activate as well as the in-flight course correction of the release vehicle on the basis of re-calculated incoming threat trajectory will not be detailed here, as it is common with most defense systems already developed and deployed. A significant difference to highlight is that the guidance of the release vehicle(s) should be based on a predefined pattern related to a reference point that will be adjusted according to the calculated threat trajectory and does not include the use of a proximity radar to approach the incoming threat. The step of confirmation of incoming threat neutralization will not be detailed either.
[0017] Abrasive material, in the form of powder grains, fibers or small fragments or flakes of metal, ceramics, sand, glass, basalt ash or any other finely divided refractory solid, will be dispersed in a wide area around the expected path of the threat to defeat in order to form a large cross-section of interaction. The release will preferably be actuated several seconds before the arrival of the threat. If the time between release actuation and interaction with the threat is lower, the dispersal of abrasive material may not be complete and the actuation point will have to be significantly closer to the actual path of the incoming threat, therefore reducing the specific interest of the present invention in comparison with more traditional interception. Actuating the release of abrasive material less than a second before the interaction with the incoming threat will require guidance systems similar to the use of proximity detonation interceptors, with the technical challenges associated with getting in close proximity to a maneuverable hypersonic vehicle. The release of abrasive material more than 10 seconds before interaction with the threat will considerably increase the uncertainty on the actual threat trajectory since a hypersonic vehicle will still be several tens of kilometers (tens of miles) from the area of interaction. Such a long time would also increase the likelihood of unexpected change of course of the threat and / or drift of the dispersed material in the air.
[0018] Technical options to disperse abrasive material will be discussed in the section “Investigations – Material dispersal and atmospheric residence time”.
[0019] Given the already extreme conditions to which vehicles moving at hypersonic velocities face due to the friction with air, it is expected that the release of abrasive material on the path of such vehicle will exacerbate thermal and mechanical constraints beyond tolerable conditions and lead to its in-flight destruction. The physical interaction of the abrasive material with the body of the incoming threat will be discussed in the section “Effect of airborne abrasive material”.
[0020] Investigations – Effect of airborne abrasive material
[0021] Basalt ashes ejected from a volcano are known to cause significant damages to engine parts of commercial airliners, as highlighted for example by the multiple flight cancellations and airspaces closures over large areas of Northern Europe following the eruption of the Eyjafjöll in Iceland in 2010 as well as documented cases of commercial aircraft incidents due to volcanic ash. This is due to the abrasive effect of small grains of mineral material in the plume of the volcano. Although the mass of solid material per unit of volume of air is only a tiny fraction of the mass of air in the same volume, those grains have a disproportionate mechanical impact and are comparable to the diamond grains in saw blades or sand on abrasive paper.
[0022] An illustration of the abrasive impact of air-dispersed sand on a moving object is the so-called KOPP-ETCHELLS effect, in which a visible corona is sometimes produced by rotary-wing aircrafts when operating in sandy conditions. The effect is caused by the pyrophoric oxidation of ablated metal particles from the abrasion shield of the rotor blades. This occurs because its freshly exposed surface reacts with oxygen to produce heat. The radial velocity of blade tips is typically subsonic, an order of magnitude slower than the low-end of hypersonic objects.
[0023] In addition to the classical mechanism of erosion, the interaction of dust particles with a solid surface in the hypervelocity regime is reportedly characterized by shockwave generation and release, leading to extensive vaporization of both the projectile and the target surface (De Angeli et Al., Nuclear Materials and Energy 41, 101735 (2024)).
[0024] Another important effect on the impacted surface in the hypervelocity regime is the thermal excitation triggered deep in the material. The extent of this region considerably increases as the temperature of the surface before impact is already elevated, especially above 500K (Dwivedi et Al., Journal of Nuclear Materials 600, 155289 (2024)). This phenomenon begins to be studied in a field related to the degradation of plasma-facing walls of tokamak fusion reactors due to the impact of high-velocity metal particles ejected by runaway electrons from the plasma. This would have a considerable effect on the protective layers of hypersonic vehicles as it will affect the material away from the surface, where radiative cooling features are ineffective.
[0025] In the case of vehicles moving at hypersonic velocity, the vehicle body and especially the leading edges (see US patent 8,256,706 B1), already experience huge thermal constraints due to friction with air, which requires those parts to be protected by a specifically designed heat shield and even active cooling features (see US patent 11,577,817). The abrasive effect of the localized dispersal of fine grains of refractory material, as highlighted above, would considerably be increased by the following factors: (1) the kinetic interaction between a static solid particle and a fast moving object is considerably more important than in the case of commercial airliners motor fans or helicopter blades, increasing with the square of the speed difference, (2) the contact surfaces are already exposed to extreme thermal and mechanical constraints, close to disruption conditions, (3) the surface would have to be made of a heat-resistant material, not a specially designed abrasion shield, (4) an abrupt change in the environmental conditions will have a far higher disruptive impact than a continuous effect on the whole flight path, (5) at this velocity, a destabilization of the vehicle could be sufficient to lead to its destruction due to the exposure of insufficiently protected surfaces, and (6) the dispersed material composition and grains density and shape can be optimized to increase their abrasive power. In addition to the exacerbated erosion factor, the pyrophoric effect on metal parts, as in the Kopp-Etchells phenomenon, would also be significant since, besides the already elevated temperature of the object as reported above, the oxygen partial pressure on the leading edge would be considerably increased.
[0026] For Hypersonic Glide Vehicles (HGV), which can move at or above Mach 10, the highest expected impact would be on the heat shield and cooling features of aerodynamic control surfaces. Those will be protected by a specially designed layer of passive or sacrificial heat protection (see Chinese patent CN 110,553,554 A) and / or active cooling features (US patent 11,577,817). A degradation of these protection features would expose the underlying material, which provides mechanical stiffness, to extreme temperatures that it is not designed to withstand.
[0027] The presence of solid particles in the air would affect the vehicle surface below the coolant blanket film of actively cooled surfaces and would abruptly degrade the material, especially the porous coolant injectors described in US patent 11,577,817. This will compromise the cooling of leading edge and aerodynamic control surfaces, in addition to the direct degradation of the surfaces themselves, which will have the double, reinforcing, effect of compromising the heat protection of the most exposed parts of the vehicle and disrupting the laminar to turbulent air flow over the surface of the wedge.
[0028] In the case of air-breathing hypersonic vehicles (hypersonic cruise missiles or manned or unmanned hypersonic aircrafts), typically moving in the low-end of the hypersonic range, the effect on the front-end shield may be less important than for HGVs due to the relatively lower velocity, however, a significant impact on the scramjet engine is to be expected, as well as on the engine inlet, stabilization fins or other protuberance of the vehicle body. This would likely trigger a destabilization of the vehicle that would ultimately lead to its in-flight destruction.
[0029] From expert judgment, based on an extrapolation of unsafe operational conditions for aircrafts in terms of volcanic ash concentration in the atmosphere, it is assessed that an order of magnitude of 10 to 100 grams of locally dispersed refractory abrasive material per square meter of cross section (about 0.1 oz / sq ft) would have a disruptive impact on a vehicle moving at hypersonic velocity. Actual tests and / or specifically optimized material could potentially draw this figure lower. If more material is necessary, technical adaptations to the options presented in the embodiments described later can be considered without departing from the spirit of the invention.
[0030] Investigations – Experimental facilities to simulate hypersonic flight conditions
[0031] Experimental facilities intended to simulate the conditions of atmospheric flight at hypersonic velocities typically involve submitting sample surfaces to a jet of plasma to simulate the interaction with the ionized air layer, but do not feature actual interaction between objects moving at relative speeds exceeding Mach 5. For the simulation of impact of high-velocity dust on the walls of fusion reactors, a system featuring a light gas gun system is used (Dwivedi et Al., 2024), involving a two-stage setup in which dust particles, encased within a macro-scale projectile, are accelerated into a vacuum chamber for impact testing. Even though this setup may involve heating the impacted surface, it does not simulate the interaction with the plasma and the corresponding degradation of the material before, during and after the impacts.
[0032] In order to reliably simulate the effect of abrasive material with a hypersonic object, an experimental facility would need to combine plasma heating of the surface with a high-velocity dust impact setup. No currently existing facility is known to be suitable for such a combination.
[0033] Investigations – Material dispersal and atmospheric residence time
[0034] The present invention relies on the technical capabilities to rapidly disperse small grains of material in a large volume of air and have those grains remaining in the target volume for at least several tens of seconds before drifting to the ground.
[0035] The aerial dispersal of powdered material can be carried out by means of explosive release from the release vehicle warhead, the in-flight aerodynamic dispersal from the release vehicle, the explosive release by submunitions ejected from one or several release vehicles or any other option in which one or several platforms are used to disperse fine grains or small fragments of material in a wide area.
[0036] The explosive release of solid material has been studied in the military field in the framework of the development of vectors for chemical or biological warfare agents, as well as the assessment of the potential impact of radiological dirty bombs. Although the results of those studies are classified, it can reasonably be assumed that the current state of the art technical options can rapidly disperse powder material in a radius of at least 100 meters (330 ft). The pyrotechnics industry has also developed significant know-how in this field.
[0037] The release of powder material in a radius of at least 100 meters (330 ft) on the path of an incoming object which would be at about 10 kilometers (6 miles) from the dispersion area at the time of the release actuation represents a maximum angular uncertainty for the determination of the expected path of about 1%. With state-of-the-art tracking radar and computational speed, possibly combined with trajectory prediction algorithms (such as those described in Chinese patents 113,269,363 B or 109,857,145 B) and especially with the rapidly evolving capabilities of artificial intelligence, it is reasonable to assume that such precision requirement is not a limiting factor. If several release vectors are used in a coordinated pattern, a cross-section in the order of magnitude of a square kilometer (0.4 sq mile) could reasonably be covered, increasing the maximum acceptable uncertainty and / or providing some margin for an unforeseen slight change of course.
[0038] It could be assessed that the maneuvering capabilities of hypersonic vehicles can compromise the prediction of their path even if a wide margin is tolerable. However, maneuvers at such velocities come at the cost of speed and range (Wright et Al., Science and Global Security 31, 68-114 (2023)). Such maneuvers would dramatically reduce the velocity of the incoming threat, which would render it vulnerable to terminal defenses, as was the case over Ukraine in early 2024 where Russian Tsirkon missiles could effectively be defeated by interceptors from Patriot systems. Evading such defenses requires hypersonic vehicles to maintain speeds significantly greater than Mach 5 (Wright et Al., 2023), which precludes significant changes of course and therefore renders the vehicles vulnerable to a defense system based on the concept described here. The combination of such a system with another one based on interceptors brings significant synergies not only to improve the likelihood of interception but also to complicate adversary’s strategies to evade missile defenses.
[0039] In terms of residence time in air, several examples show that particles of refractory mineral material can last in the atmosphere for very long periods of time. Basalt ashes from volcano eruptions remain in the atmosphere for many days or even weeks. Sand particles transported by winds can travel very long distances, for example it is not uncommon that sand particles from Sahara are transported as far North as Paris or Brussels. After the 9-11 terror attacks, concrete and asbestos dust remained a significant concern in Manhattan for several days. In the framework of the present invention, dispersed particles should remain in a target area for at least 10 seconds which, on the basis of the examples above, is a reasonable expectation.
[0040] Particles in the range of 0.1 to 1 mm and a density comparable to sand grains have a settling velocity in the range of 1 to 5 m / s (Del Bello et Al., Nature Sci. Rep. 7, 39620 (2017)). Even the high-end of this range represents a drift distance within a few seconds that remains small compared with the expected size of the affected area. This area will therefore be largely determined by the release method and turbulence from the release vehicle and will display relatively minor variation within the timeframe of a few seconds before and after the expected arrival of the threat.
[0041] The considerations above show that, in the optimization of the grains size and density, more emphasis can be placed on factors such as the ease of dispersal or the abrasive power rather than settling velocity. This would especially be valid if the material is released in the troposphere (up to 12 km / 40,000 ft), the layer of the atmosphere with the highest pressure.
[0042] The release of material on the trajectory of the incoming threat during its glide phase, at an altitude of 30 to 40 km (about 100,000 – 130,000 ft), would significantly improve the predictability of the expected trajectory, increase the likelihood of threat neutralization and, should this neutralization fail, allow for a further window of interception for terminal defense. This would however require a careful selection of grain size, shape and density to prevent excessive gravitational drag due to the low air density at such altitude.
[0043] A slow drift of the material, whether due to the gravitational drag or the effect of wind, may be accounted for as an offset in the determination of the point of release on the basis of the calculated flight path of the threat. Besides, a wide range of grain sizes (and therefore of settling velocities) can be exploited to widen the vertical distribution of the affected cross-section.
[0044] Investigations – Cost considerations
[0045] The concept described in this invention can be considered as a low-cost option compared with traditional missile defense approaches for the following reasons: (1) It does not require the vectors to dispatch to be hypersonic, (2) in some embodiments of the invention, the vectors used to disperse material are reusable dispensers rather than expandable interceptors, and (3) although large quantities of material need to be dispersed, it could potentially be as cheap as dry fine sand.
[0046] Investigations – Potential environmental side-effects
[0047] Potential environmental side effects of the atmospheric release of powdered refractory material will not be different in nature, and significantly lower in intensity, than naturally occurring dispersal of sand by wind blowing from desert areas or basalt ash ejected from volcanoes.
[0048] A release of the material in the troposphere, as suggested earlier, would be significantly below the ozone layer, and would not affect it.
[0049] If small fragments of metal or ceramics are used, their residence time in air will be lower than powdered mineral material, and their area of ground deposition will be far more localized, in the region of the dispersal actuation and therefore of the interaction with the incoming threat. Their impact will be dwarfed by the fall of the multiple components of the defeated threat itself.
[0050] Investigations – Assessment of Prior Art
[0051] To the knowledge of the inventors, the closest earlier invention describing the spreading of bulk material on the path of an incoming missile relates to the sprinkling of fuel or explosive material specifically targeting air-breathing missiles (JP 6,572,007 B2). Since the concept does not involve the exploitation of the abrasive properties of refractory material, requires the ignition of the material dispersed, is specific to air-breathing missiles, does not specifically relate to hypersonic vehicles, does not involve guided release vehicles and makes use of a sprinkling device that would only be suitable for low-altitude tactical missiles, there are compelling evidence to claim that both inventions are sufficiently different to not overlap.
[0052] Dispensing particulate matter as an option to disrupt or destroy hypersonic weapons had been suggested (Karako, Dahlgren, Complex Air Defense, Report of the CSIS Missile Defense project (2022)), but this could not be considered a genuine invention as it was more an hypothesized exploitation of an identified vulnerability, among a range of other suggestions, rather than a concept description. The particulate material broadly considered in the relevant section of the report include metallic, pyrotechnic as well as other “purpose-designed” particles with potentially incendiary or corrosion properties but it does not detail degradation processes by chemically inert grains of refractory material. Besides, the proposed employment explicitly focuses on dispensing material in the upper atmosphere, and early in the missile trajectory, which would hardly be practical as described in the preceding sections of the present disclosure.EXAMPLES
[0053] In the following description, the invention will be discussed primarily as a defense layer in the phase of a missile path where its velocity is in the hypersonic range and interception by classical means is particularly difficult. In addition to the expected destruction of the identified incoming threat, the relatively persistent nature of the threat-countering conditions in the vicinity of the targeted asset will also create significant uncertainty for the adversary regarding the expected efficiency of considering a salvo of missiles.
[0054] The present invention is specifically intended to defeat incoming missiles or aircrafts moving at hypersonic velocities. Without prior knowledge of the type of vector to defend against, it should be used in coordination with other air defense systems. Ideally, several aspects that are common to different systems can be provided by a shared, centralized, capability. These aspects typically cover threat detection, tracking, determination of most probable trajectory, selection, activation and guidance of interception system and / or post-interception threat neutralization confirmation. In this process, release vehicles of abrasive material will be treated as classical interceptors, although their guidance and payload actuation will be specific.
[0055] The system would be a layer of defense on the path of long-range hypersonic vehicles after their entry in the troposphere, where the atmosphere pressure allows for longer latency for dispersed material, but still at a significant distance from the asset that was targeted to allow for the disrupted features of the vehicle to lead to its destruction without damaging the high-value asset to protect. The window of interception would most likely be in the high troposphere, at an altitude of 6 to 12 km (20,000 to 40,000 ft). This would be on the descending phase from the cruise altitude / glider trajectory towards the target. Higher altitude release to defeat an HGV in its glide phase may also be considered in other exemplary strategies.
[0056] Depending on the asset or area to protect, one or several threat destruction regions will be identified, which will then determine the pre-positioning of interceptors (or release vehicles) launch sites according to the range and speed of those vectors. After detection of a specific threat and determination of its speed, a stage-gate approach will determine decision points at times determined by the remaining time to reach the threat destruction area. Such decision points (which would ideally be automatic selections based on the data provided by sensors and processed by artificial intelligence) will involve but are not limited to (1) the selection of the most suitable system to activate, (2) launch orders of interception vehicles, (3) determination of the threat destruction box within the threat destruction region, and guidance of interceptors towards this area, (4) actuation of abrasive material release.
[0057] The threat destruction box is determined by an axial and a radial component, forming a cylinder around a section of the incoming threat calculated trajectory. The axial component will be determined on the basis of the optimum lapse of time between release of material in the box and the arrival of the incoming threat and will account for the time required for the release vehicle(s) to reach the box. The radial component would be a distance from the expected path, representing the uncertainty of the actual trajectory determination. This component will get smaller as the threat gets closer and the calculated trajectory is refined. The time-sensitive determination of the threat destruction box, the suitable guidance of release vehicles towards this box and the precise actuation of their release system require state of the art tracking capabilities, high-speed calculation, real-time data link with the vectors and a good 3-D representation of the environment.
[0058] In a preferred strategic employment of the present invention, one or several release vehicles will approach the threat destruction box, in which abrasive material will be released, from a direction horizontal and perpendicular to the expected path of the incoming threat which will likely be a downwards trajectory at an angle lower than 45 degrees. With this approach, a late correction of the vertical component of the calculated trajectory can be matched with a correction of the flight altitude of the release vehicle, whereas a correction of the horizontal component can be addressed by a slightly earlier or later actuation of the release. In order to increase the level of reactivity of the system for such late corrections, two vehicles will preferably approach the box from opposite directions. With no vehicle heading towards the incoming threat, the likelihood of course change would be reduced since sensors based on proximity radar detection or on corrected Doppler effect would not trigger reactive avoidance maneuvers.
[0059] In an exemplary embodiment of the strategy described above, two fast-moving release vehicles with an explosive warhead intended to disperse a payload of about 100 kg (several hundred pounds) of specially optimized powder material are launched and guided towards a threat destruction box from both sides. This box will be continuously re-calculated and guidance corrections provided to the vehicles. At about 100 meters (330 ft) from the threat destruction box, several seconds before the arrival of the threat, both vehicles’ warheads will explosively disperse their payload, covering a cross-section of about 100 meters (330 ft) vertically and 200 meters (650 ft) horizontally. This would bring about 10 grams of abrasive material per square meter of cross-section (0.03 oz / sq ft) on the path of the incoming threat, in addition to the possible collision with fragments of the vehicle itself that would not yet have fallen to the ground. If a horizontal correction of the threat trajectory is to be applied before material dispersal, the actuation of both vectors can be corrected, with the vector in the direction of the path correction being actuated earlier, and the other vehicle later. Note that it is not necessary that the release vehicles reach the expected threat trajectory simultaneously. Instead, they can each be assigned a different threat destruction box, depending on their estimated time of arrival in the area.
[0060] In another embodiment, reusable release vehicles, less maneuverable and reactive but with a larger payload, will be used. Each vector will release a payload of about a metric ton of powdered material as a curtain in its wake. As in the previously described embodiment, two vectors will approach the threat destruction box from both sides. They will be guided so that they will arrive at about one kilometer (0.6 miles) from the calculated threat path about 10 seconds before the arrival of the threat, allowing for some margin of uncertainty on the actual encounter timing. At this point, the material release will be actuated, as aerodynamic dispersal from the vehicle itself or through the ejection of bomblets or submunitions each carrying several kilograms (several pounds) of material. This would create a curtain of about 100 meters (330 ft) high and one kilometer (3,300 ft) wide on each side of the path of the incoming threat, that should be completely released about 5 seconds before the threat arrival, with both vehicles closing the gap from each side. As for the previous embodiment, if a late vertical correction needs to be applied the flight altitude of the release vehicles can be adapted, and for a horizontal correction before the beginning of the abrasive material release, the release actuation of the vehicle in the direction of the correction can be set earlier and the other one delayed. A late horizontal correction, after the material release actuation, is addressed by the wide coverage on both sides of the affected area. To account for a drift of dispersed material at the beginning of the release process, the vehicles can approach the threat destruction box from a higher altitude at a slight downward angle.
[0061] In a variant of the previously described embodiment, the release vehicle(s) may already be in flight before the assessment of the velocity of the incoming threat. Reusable release vehicles can be dispatched pre-emptively upon reception of intelligence reports pointing towards an imminent threat and / or the detection of the launch of a long-range missile, even before the actual nature of the warhead is known.
[0062] An exemplary employment of this variant would consist in the design and use of powder release canisters (as described in Canadian patent application CA-3264423) attached to the under-wing and / or underbody pylons of a loitering unmanned vehicle. For example, a decommissioned fighter jet equipped with a remote-control kit and typically used as target for training, such as the QF-16, could be used as unmanned vector in the framework of this invention. It can carry an external payload of 2,000 lbs under each wing, significantly more than the amount discussed above. Such a platform could loiter at subsonic speed for a significant amount of time and reach the treat destruction box in full after-burner at up to Mach 2 upon request, releasing between 1 and 2 metric tons of powder material on a 1 km long section in about 2 seconds. In this configuration, the powder material could be released at an altitude of up to 50,000 ft (15 km), the service ceiling of this kind of platform. Similarly, a QF-18 version could be considered for a carrier-based defense system and could be fitted with the same canisters.
[0063] In another exemplary employment of the variant, a bulk material dispenser may be fitted in the cargo bay of a subsonic transport aircraft that would release tens of tons of material over a large area more than several seconds before the arrival of an incoming threat. Such a release mechanism may resemble the large-scale dispersal of fire-quenching powder from fire-fighting aircrafts, although from a higher altitude, or would preferably involve more controlled distributed release over a longer flight section. This exemplary employment would be less specific to the expected path of the threat but would further create uncertainty for the adversary regarding the expected efficiency of its strikes, especially if the affected region bridges areas more densely covered by terminal-phase missile defense systems based on other technologies.
[0064] The use of a larger amount of bulk material and / or more release vehicles than described in the exemplary embodiments would increase the affected cross-section, the quantity of dispersed material per unit of cross-section and / or the redundancy of the system.
[0065] In another strategic employment of the present invention, a screen of powder material may be deployed at low altitude between a high-value asset (such as an aircraft carrier) and an identified launch platform for short-range hypersonic cruise missiles upon detection of launches, in order to protect the asset against a salvo of missiles that would otherwise be challenging for point defenses.
[0066] It is to be understood that the present invention is not limited to the specific embodiments described above, and that various changes or modifications may be made by one skilled in the art within the scope of the appended claims without departing from the spirit of the invention. The embodiments and features of the embodiments of the application presented may be combined with each other arbitrarily without conflict.
Claims
A method to defend against missiles or aircrafts by atmospheric dispersal of abrasive material on the expected path of a vehicle moving at or close to hypersonic velocity.The method of claim 1 where the abrasive material consists in small grains, fibers, fragments, flakes or foils of metal, sand, glass, ceramics or other solid refractory material whose composition and particles size, density and shape are chosen and optimized for both their abrasive power at elevated temperatures and low gravitational drag in air so that dispersed material remains close to the point of release for at least several seconds.The method of claim 1 or 2 where the expected path of the vehicle is determined with artificial intelligence algorithms.A method to simulate, in experimental facilities, environmental conditions created by the methods described in claims 1 or 2, through the simultaneous or sequential combination of target material exposure to a jet of plasma and the impact of accelerated grains of powder material.The method of any preceding claim where one or several vectors are used to disperse solid bulk material.A system to implement the dispersal of abrasive material as described in claims 1 to 5.A system to disperse material according to claim 6 where the vector(s) comprises at least a vehicle and a device to actuate the dispersal of solid bulk material.A system of claim 7 where the dispersion device is made of one or several material dispensers or storage canisters, each coupled with an actionable release mechanism, designed to be attached to an external pylon or fitted in the internal bay of a manned or unmanned platform.A system to develop and optimize the methods and systems described in Claims 1 to 8.A system to test and optimize the resistance of hypersonic vehicles to an environment modified by methods and systems described in Claims 1 to 8.