IL295103A - Method for minimizing detonation damage to a watercraft - Google Patents

Description

thyssenkrupp AG 1 Method for Minimizing Detonation Damage to a Watercraft The invention relate sto a method in which the generation of a liquid mist is used to minimize the effect of a detonation in the watercraft.

Theoretically, it is known that liquid mist can be used to influence the propagation of a detonation wave and thus minimize damage.

The disadvantage is that damage almost always occurs when a liquid mist is generated, 10 in particular electronic components are regularl affectey d. In addition, extinguishing liquid can of course also have an influence on the buoyancy.

To make matters worse, military ships are mainly equipped with the necessary equipment to identify incoming threats. Especially on these ships, however, the different ship 15 systems are shielded against each other, making easy integration difficult.

From US 2006/0196681 A1, the suppression of a fire by means of a water mist is known.

From WO 2003/061769 A1, a fire extinguishing device and a fire extinguishing method 20 are known.

From US 2007/0159379 A1, a method and a device for the protection of a ship against homing missiles is known.

The object of the invention is to generate a method that allows a reduction of detonation damage by the formation of a liquid mist and at the same time minimizes the collateral damage caused by the liquid. The object of the invention is not to compete with short­ range defense systems or countermeasures, but to minimize damage reduction after their failure and thus the damage caused by the impact of a missile.

This object is achieved by the method having the features specified in claim 1. Advantageous developments result from the subclaims, the following description and the drawings. thyssenkrupp AG 2 The method according to the invention for damage minimization on a watercraft has the following steps: (a) providing the watercraft and a database, wherei nthe watercraft has spaces Rn, 5 wherein the database for at least one space Ri contains time information tri, wherein the time information tri is the time required to generate a liquid mist in the space Ri to which this time information tri is assigned; (b) detecting and locating a threa tin the form of a flying object; (c) determining the movement of the flying object; (d) determining the location of a collision between the flying object and the watercraft; (e) identifying the space Ri of the watercraft adjacent to the collision location; (f) determining the time information tri for that space Ri from the database; (g) determining the time t0 at which the flying object has reached a position at which the remaining flight time to the collision location corresponds to the time information tri; (h) at time t0 or at time t0 – Δt0 start the generation of a liquid mist in the space Ri, wherein Δt0 is a predetermin edtolerance time interval.

Watercraft within the meaning of the invention are in particular military watercraft ,in particular military surface vessels, for example and preferably, cruisers, destroyers, 20 frigates, corvettes, task group supply vessels, mine seekers, mine sweepers, aircra ft carrier helicos, pter carrier amphibios, us warships, landing craft ,battleships.

The watercraft has n spaces Rn, wherein n is a natural number. A certain space results from the numbering of the spaces. For example, a watercraft has 10 spaces, so there are 25 spaces R1, R2, R3, R4, R5, R6, R7, R8, R9 and R10. Ri is the ith space of the watercraf t, where i is a natural number between 1 and n.

Spaces in the sense of the invention are spaces inside the watercraft for, example the bridge, mess, galley, quarters, corridor engines, rooms and the like. Spaces are thus 30 interiors of the watercraft, wherein these, such as a hangar, can also have a large opening to the outside. A space usually has walls, a floor and a ceiling. Spaces usually have a door for entry, wherein there are also spaces in a watercraft that can only be entered, for thyssenkrupp AG 3 example, through an opening in the ceiling, for example a battery space. Space is therefore to be understoo din the sense of a room.

Virtual positions outside the watercraft such, as in US 2007/0159379 A1, are not spaces 5 within the meaning of the invention.

The respective time information tr1, tr2, ... trn-1, trn for the spaces R1, R2, ... Rn-1, Rn is placed in the database. The time tri for a space Ri results from the time required to generate a liquid mist in the space Ri. This time depends, for example, on the size of the 10 space and, for example, the number of sprinkle rsystems that can be used to generate the liquid mist.

It is not necessary to store time information tri for each space Ri of the watercraf t.For example, spaces that are internal or permanently below the waterline can be excluded if 15 an impact of a missile is considered unrealistic here. Likewise, spaces could be excluded in which no liquid mist can be generated and should not be generated for, example computer spaces that have an automatic extinguishing device using CO2. Thus at least the spaces Ri which have a device for generating a liquid mist are advantageously recorded in the database. Particularl ypreferably, at least the spaces Ri are recorded 20 which are arranged on the outside of the watercraft in the above water region.

Flying objects include all sorts of threats from warheads, grenades, cruise missiles, missiles to aircraft. These can fly purely ballistically, fly actively or fly ballistically with control options, wherein the control options can be implemented as active or passive.

The spaces R1, R2, ... Rn-1, Rn can also be grouped in functional groups or contiguous locations and controlled together. For example, the ammunition stores, ship’s sections or external spaces on the por tor starboard side can form common groups. It is essential to form the groups of spaces in such a way that the spread of damage to the ship is slowed 30 down and the damage is reduced. A criterion for the formation of spatial groups can be the structural design of the ship. thyssenkrupp AG 4 An advantage of the invention is also that this additional protection is not recognizable to an enemy. Practically all larger military watercraft have both a radar system and a sprinkler system, which is suitable for generating a liquid mist. However, these are usually integrated into different and strictly separate ship’s systems. While the combat 5 management system is connected to the radar, an integrated platform management system controls the firefighting devices. Such a military watercraft can easily be equipped with a control system for carrying out the method according to the invention, but which is not externally recognizable to an enemy, in contrast to heavy armor for, example, so that the weakened detonation effect of a warhead is not predictable for the enemy in the field.

In step h) a liquid mist is thus generated inside at least one space and thus inside the watercraft .In principle, this is disadvantageous for two reasons. On the one hand, unnecessar yextinguishing water can cause damage, ranging from electronic devices to paper documents to food or clothing. On the other hand, water also gets into the interior 15 of the watercraft which, is usually avoided in the interest sof buoyancy. The core of the invention is now to condone acceptance of these disadvantages in orde tor minimize the effect of the detonation of a warhead. This is not, or at least not primarily, about fighting a potentially occurring fire before it arises, but rather to mitigate the propagation of a pressure wave or a plasma lance generated by a warhead and thus to reduce the primary 20 damage caused by a warhead.

Steps b) and c) are preferably carried out by means of radar, optical sensors and/or acoustic sensors. Particularl ypreferably, steps b) and c) are carried out by means of radar.

The determination of the movement in step c) can be carrie dout with two time separated measurements and the measured position difference Altern. atively, however, it can also be carried out directly, for example by means of a frequency shift (Doppler effect).

Preferably, all steps of the method are carried out on a watercraf t.However, it is also conceivable that, in particular in a convoy, steps b) and c) are carried out by a second watercraft for, example and in particular an escort ship, for example a destroyer, and the determined data are then transferred to the first watercraft for, example a task force thyssenkrupp AG supply ship, which itself does not have a radar system or at least not a comparable radar system. If necessary, step (e) may also be carried out on the second watercraft.

It may be advantageous that in step h) a liquid mist is generated not only in the space Ri, 5 but that in the event of an acute threat this may be carried out in neighboring spaces, for example in spaces Ri-1 and Ri + 1. For this purpose, steps f) to h) are preferably carried out for each space Ri-1, Ri and Ri +1. This results in a time t0,ri-1 for space Ri-1, a time t0,ri for space Ri and a time t0,ri+1 for space Ri+1.

It may also be advantageously provided that all spaces are selected that lie within a ship’s section or a lockable region. This ensures that the region over which a pressure wave or a fire can spread is already filled with liquid mist and the damage is reduced over the entire region.

Of course, after step b), further measures can be taken to prevent the impact of the missile, for example the attempt is made to destroy the missile with short-range defense systems before it reaches the watercraft Coun. termeasures can also be used to deceive the missile's target-seeking function and thus lead the missile away from the watercraf t.

These measures can also be carried out in parallel with step h). Although water damage 20 has already occurred in the spaces concerned, avoiding the impact is always the best option. The method according to the invention thus represent san additional and downstream line of defense to the conventional systems of short-range defense and countermeasures.

In a further embodiment of the invention, steps c) to e) are continuously repeated to detect changes in motion. As a result, both course corrections by the flying object and changes in the movement of the watercraft can be taken into account. This is preferr ed,since today simple artiller shellsy already have a certain degree of maneuverability, especially in a range-increased version. And in the case of anti-ship missiles, strong maneuvers to 30 overcome hardki lldefensive measures are common today, especially for the target approach .If the change in step e) identifies another space Ri, then steps f) and g) are also carried out again. thyssenkrupp AG 6 Likewise, a continuous observation of the flying object can also determine that it could be eliminated, for example, by a hardkill and that a further threat no longer exists. In this case, the method according to the invention is then preferably aborted as quickly as possible to avoid unnecessar ywater damage.

In a further embodiment of the invention, after the impact of the flying object into the watercraft at time tein, the generation of the liquid mist is continued for a period of ΔtEin. During the period from tein to tein + ΔtEin, fire monitoring is carrie dout in the space Ri to determine whether the impact has caused a fire in the space Ri. In the event that a fire 10 has been detected, the generation of the liquid mist is continued beyond the time tein + ΔtEin. In the event that no fire has been detected, the generation of the liquid mist is stopped at time tein + ΔtEin.

In a further embodiment of the invention, steps b) and c) are carried out by a combat 15 management system. The combat management system on a military watercraft includes, for example, the controls of the sensors for detecting the threat situation, for example the radar, as well as the control of the effectors, for example guns, missiles or short-rang e defense systems. The combat management system is therefor pare ticular lyshielded for safety reason sin order to prevent any unwanted intervention from the outside. Steps d) 20 to h) are carried out by a control system. The control system may be in particular in the form of an independent system for carrying out only this part of the method according to the invention outside the other ship systems, which allows an optimal integration into the safety architecture and an optimal retrofit. The combat management system and the control system are only connected via a one-way connection for the transfe rof data from 25 the combat management system to the control system. Unidirectional connections are established, for example, via so-called data diodes and ensure that, for example, no malware can be transferred from the control system to the combat management system and thus the security of the system is fully guaranteed.

In a further embodiment of the invention, the generation of a liquid mist in step h) is carried out by a control system in that the control system transmits a fire message to the firefighting system. As a result ,the firefighting system initiates firefighting measures that lead to the generation of the liquid mist. For example, and preferably, the sprinkler system thyssenkrupp AG 7 in the space Ri is activated. The advantage of this system is that no new systems have to be installed on the watercraft apart from a control system. The control system uses the existing ship systems. This saves space, weight and integration complexity and enables optimal retrofitting.

In a further embodiment of the invention, a non-conductive fluid is used to generate the liquid mist, for example CF3CF2C(O)CF(CF3)2. For example and preferably, the watercraft has a stock of non-conductive fluid to allow the generation of the liquid mist at least from t0 to tein+ ΔtEin. If the non-conductive fluid is used up, further firefighting can also be carried 10 out with fresh water or seawater. Damage to electronics, for example, is then accepted, as an arbitrarily large supply of non-conductive fluid does not make sense and firefighting takes precedence over damage caused by extinguishing water.

In a further embodiment of the invention, course data and speed data of the watercraf t are used to determine the collision location in step d). Due to the current course ,an accurate prediction of the future location of the watercraft is possible. While this information for the flying object can only be predicted based on the past, this additiona l information is available to the watercraft for its own future, which increases the probability of prediction.

In a further aspect, the invention concerns a military watercraft which is designed to carry out the method according to the invention.

In the following, the method according to the invention is explained in more detail on the 25 basis of an exemplary embodiment shown in the drawings.

Fig. 1 watercraft Fig. 2 first threat scenario Fig. 3 second threat scenario In Fig. 1 a watercraft 10 is shown strongly schematized. The watercraft 10 has a radar 40, which is controlled by a combat management system 50. The combat management system 50 is connected to a control system 30 via a data diode 60. Via the data diode 60, thyssenkrupp AG 8 the combat management system 50 transmits information about approaching flying objects 80 to the control system 30. The control system 30 has a database in which the time information tri is stored for all spaces Ri of the watercraft 10. If the control system 30 identifies a space Ri that is threatened by an approaching flying object 80 and is to be 5 protected by a liquid mist, the control system 30 transmits a fictitious fire message for the space Ri to the integrated platform management system 70 at time t0. The integrate d platform management system 70 has control over a firefighting system, which also includes the firefighting means Bi in the spaces Ri. Due to the fictitious fire message, the integrated platform management system 70 activates the firefighting means Bi in the 10 affected space Ri. As a result, a liquid mist is formed in the space Ri at exactly the moment tein when the flying object 80 hits the space Ri and the detonation effect is minimized.

Fig. 2 shows a first scenario with a purely ballistic flying object 80. At a time td, the flying object 80 is detected, and the directio nand speed are determined. This time td is shown 15 in fig. 2a. However ,since the watercraft 10 is not at rest, it is moving, as can be seen in the course of fig. 2a via fig. 2b to fig. 2c. Since the control system 20 receives the information on this own movement from the integrated platform management system 70, the control system can already recognize the space R5 as the impact site at time td. At the time t0 shown in fig. 2b the remaining residua flightl time of the flying object 80 is equal 20 to the time required to generate a liquid mist in the space R5, which is why the contro l system initiates it at this time. Fig. 2c then shows the impact at time tein, at which the liquid mist in the space R5 is fully formed.

Fig. 3 shows a slightly different picture. Analogous to fig. 2a, at time td in fig. 3 the flying 25 object 80 is detected, the directio nand speed are determine dand the impact for the space R5 is predicted At. this time, however, the flying object 80 slightly changes its directio nof flight, which is detected by the radar 30 between td and t0. As a result, the prediction of the impact on space R3 is changed and at the time t0, which is shown in fig. 3b, the liquid mist is generated in the space R3. The impact of the flying object 80 in the 30 space R3 at time tein is shown in fig. 3c.

In orde rto cover a further change in the trajector yof the flying object 80, which is unpredictable, a liquid mist can be generated at time t0 in spaces R2, R3 and R4. This thyssenkrupp AG 9 increases the damage caused by the liquid mist, but a possible deviation of the flying object 80 from the predicted course still leads to damping of the detonation, even in the event of an impact into the space R2 or R4. Spaces located further away have too low a probability of threat ,so that no liquid mist is generated here. thyssenkrupp AG Reference Characters Watercraft Database Control system 40 Radar 50 Combat management systems 60 Data diode 70 Integrated platform management system 80 Flying object R Space i (i is a natural number) B Fire extinguishing means i (i is a natural number) thyssenkrupp AG 11

Claims (8)

Claims

1. A method for minimizing damage on a watercraft (10), wherei nthe method has the following steps: 5 a) provision of the watercraft (10) and a database (20), wherein the watercraf t (10) has spaces Rn, wherei nthe database (20) contains time information tri for at least one space Ri, wherein the time information tri is the time required to generate a liquid mist in the space Ri to which this time information tri is assigned, 10 b) detecting and locating a threat in the form of a flying object (80), c) determining the movement of the flying object (80), d) determining the location of the collision between the flying object (80) and the watercraft (10), e) determining the space Ri of the watercraft (10) adjacent to the location of the 15 collision, f) determining the time information tri for this space Ri from the database (20), g) determining the time t0 at which the flying object (80) has reached a position at which the remaining flight time to the collision location corresponds to the time information tri, 20 h) at the time t0 or at the time t0 – Δt0 star tthe generation of a liquid mist in the space Ri, wherein Δt0 is a predetermined tolerance time interval.

2. The method as claimed in claim 1, characterized in that steps c) to e) are continuously repeated to detect changes in motion, wherein another space Ri is 25 identified by a change in step e), and the steps f) and g) are carrie dout.

3. The method as claimed in any one of the preceding claims, characterized in that after the impact of the flying object (80) into the watercraft (10) at time tein the generation of the liquid mist is continued for a period of time ΔtEin, wherei nduring 30 the time from tein to tein + ΔtEin fire monitoring is carried out in the space Ri and, in the case of a detected fire, the generation of the liquid mist is continued over the time tein + ΔtEin, wherei nin the absence of a detected fire the generation of the liquid mist is stopped at time tein + ΔtEin. thyssenkrupp Marine Systems GmbH thyssenkrupp AG 12

4. The method as claimed in any one of the preceding claims, characterized in that the steps b) and c) are carried out by a combat management system (50), wherein the steps d) to h) are carrie dout by a control system, wherein the combat 5 management system (50) and the control system (30) are only connected to the control system (30) via a unidirectional connection for the transfe rof data from the combat management system (50) to the control system (30).

5. The method as claimed in any one of the preceding claims, characterized in that 10 the generation of a liquid mist in step h) by a control system (30) is carrie dout in that the control system (30) transmits a fire message to the firefighting system and as a result the firefighting system initiates firefighting measures leading to the generation of the liquid mist. 15

6. The method as claimed in any one of the preceding claims, characterized in that a non-conductive fluid is used to generate the liquid mist.

7. The method as claimed in any one of the preceding claims, characterized in that course data and speed data of the watercraft (10) are used to determine the 20 collision location in step d).

8. A military watercraft (10) for carrying out the method as claimed in any one of the above claims.