GB2054110A - Ballistic and Splinter Protection - Google Patents

Abstract

The invention relates to apparatus such as turrets, gun carriages. armoured hulls, weapon platforms or the like for use on land or sea and of light metal construction, comprising a load-bearing outer part 2 provided on its inner surface with a steel or plastics plate 3 which distributes and disperses and largely absorbs residual kinetic energy of a projectile, missile, splinter or the like which penetrates the outer part in use. <IMAGE>

Description

SPECIFICATION Ballistics and/or Splinter Protection Technical Field of the Invention The invention relates to an arrangement for improving protection against bombardment and splinters, particularly in the case of external loadcarrying parts such as turrets, gun carriages, armoured hulls or the like of weapon platforms for use on land or sea and of light metal construction, preferably of a cast or welded type.

Background Art Weapon systems such as automatic quick firing guns or the like installed on, in or comprising weapon platforms for land or sea use are normally protected against direct hits and splinters from missiles, mines or bombs by means of protective devices in the form of hood-like cladding, domes, towers, turrets or the like. These are more or less heavily armoured.

Present-day developments are basically aimed at providing armour for weapon platforms for use on land or sea that is as light as possible while providing a high degree of protection, in order to reduce the total weight of such platforms and keep it at least within tolerable limits.

Although in the case of specifically heavy weapon platforms, for example combat armour of fairly high tonnage, bulkhead armour consisting of several steel armour plates, layers of armour of various materials including also non-metallic materials such as ceramics, etc., have already been considered and used, such protective devices and arrangements appear relatively unsuitable, on grounds of weight alone, for use in specifically light weapon platforms in for example armoured combat vehicles or armoured reconnaissance vehicles, motor torpedo boats, etc. When using such weapon platforms, the weapons are to an increasing extent surrounded with ballistic protective hoods of light metal.

Whether or not it is preferred to have for example a hood or turret of cast or welded construction depends, inter alia, on the intended use or application of the platform.

In British Patents 17 224 and 20 020 it has already been proposed to cast alloy steel plates in specific geometrical configurations, for example overlapping or staggered, integrally in ballistic protective arrangements consisting of light metal or the like.

Bearing in mind the actual state of ballistics and the relevant circumstances, protective arrangements of the type proposed in British Patent Specifications Nos. 17 224 and 20 020 were able reliably to provide sufficient enemy action shortly after the end of the 1 9th century.

However, they no longer satisfy present-day requirements in view of the increasingly sophisticated highly combat-effective ammunition, and are thus of relatively limited value.

Disclosure of the Invention In view of the diametrically opposed developments of ballistic protection on the one hand and highly combat-effective ammunition on the other hand, it is an object of the invention to provide a weapon protection arrangement which, while fully retaining the advantages of a light metal construction, is not only a match for highly combat-effective ammunition but is even superior to it, and which is also highly cost-effective.

According to the invention there is provided apparatus such as turrets, gun carriages, armoured hulls, weapon platforms or the like for use on land or sea and of light metal construction, comprising a load-bearing outer part provided on its inner surface with a steel or plastics plate which distributes and disperses and largely absorbs residual kinetic energy of a projectile, missile, splinter or the like, which penetrates the outer part in use.

Using the invention it is possible to provide a loadbearing external part, for example a turret, gun carriage or armour plating, etc., on its inside with one or more suitably and adequately shaped steel or plastics plates that will distribute and disperse and at the same time absorb residual kinetic energy of a projectile, missile, splinter or the like which in use penetrates the external part.

The plate or plates which may distribute and at the same time largely absorb the residual energy may consist either of a sufficiently thin but high alloy and tough steel, or of a tough and elastic plastics material, for example a plastics from the polycarbonate range.

The manner in which the plates are secured to the load-bearing outer part may vary. Thus, the steel plates may be cast integrally in one piece with the inside of the load-bearing outer part, while the plastics plate or plates is or are detachably secured to the inside of the loadbearing outer part by releasable securing means, e.g. by bolts or the like.

A further embodiment of the invention also envisages, when using steel plates to distribute and disperse the kinetic energy, providing the steel plates with a plurality of reinforing hooks or clamps arranged in different planes, and which are cast integrally in the material of the loadbearing outer part when the latter is reinforced with the steel plates.

The invention provides, inter alia, the following technological advantages: (i) The plates joined to the loadbearing outer part do not exercise any kind of load-bearing function. They serve primarily and exclusively to absorb and also distribute and disperse the residual kinetic energy of projectiles, missiles, splinters or the like that have penetrated the light metal of the load-bearing outer part.

(ii) The plates also, as a secondary function, serve as a protective trap for any splinters that may have been chipped off or become detached from the load-bearing light metal part.

It will be understood that the system of steel plates cast from the inside onto the load-bearing light metal wall, or bolted-on plastics plates, does not noticeably increase the weight of the overall construction.

The use of steel plates does not additionally increase the wall thickness of the load-bearing outer part, and they simply occupy the space of the displaced light metal. On the other hand, when using plastics plates the loadbearing outer part can be reduced from the front inwards by the amount of the plate thickness by means of an appropriate structural design and casting technique.

Although high alloy and tough materials of relatively small wall thickness have proved advantageous for the steel plates, plastics plates based on polycarbonate provide outstanding advantages in certain specific appiications on account of their extremely high toughness and elasticity. Such materials are also particularly suited to absorb and distribute the residual kinetic energy of a projectile, missile, splinter or the like that has penetrated the light metal wall.

In the case of an unaltered or even reduced wall thickness, e.g. of a turret, a higher ballistic protection and at the same time a shorter penetration length can be achieved if in the first place the full wall thickness of the load-bearing light metal wall is effective in converting the impact kinetic energy before the steel or plastics plate, which is by far tougher and more elastic, disperses and fully absorbs the residual kinetic energy.

Even with high residual energies, a missile that is for example lodged in the steel or plastics plate no longer presents any danger to the operationg crew or those parts of the weapon platform requiring protection since, in contrast to the material behaviour of the light metal, the tough elastic steel or plastics plate(s) fully eliminates any splintering effect. This means that the steel or plastics plate(s) arranged on the inside of the load-bearing outer part, e.g. the turret of an armoured vehicle, is an ideal protective trap for secondary splinters that may be formed if the light metal body experiences a direct hit. Such secondary splinters cannot harm or damage humans or the interior of the weapon platform since they are rendered ineffective by the "skintight" steel or plastics plate(s).

The proposed steel plate(s) in or on the interior of the load-bearing outer part can be reinforced by means of suitable structural and constructional measures by mounting reinforcing hooks or clamps in different planes on the steel plates, which are cast integrally with the plates in the light metal.

Finally, the steel plate cast on the light metal proves to be advantageous insofar as it acts as a chill plate, by means of which the material structure and constitution of the light metal body adjacent to the steel plate can be compacted or homogenised in a completely desirable manner.

Embodiments of the invention are hereinafter described, by way of example, with reference to the accompanying drawings.

Brief Description of the Drawings Fig. 1 is a vertical section through a turret according to the invention made of a light metal and reinforced on the inside with steel or plastics plates; Fig. 2 is a vertical section through the turret of Fig. 1 along the section line A-B; and Fig. 3 is a vertical section through a turret according to the invention having a steel or plastics plate bolted on the inside thereof.

Best Modes for Carrying Out the Invention Referring to the drawings, Fig. 1 diagrammatically illustrates an armoured turret 1 in vertical section, which turret 1 consists of a light metal hood 2 as a load-bearing outer part.

The turret 1 may, depending on requirements, either be cast or made in the form of a welded construction.

The hood 2 is reinforced on its inside 2a with one or more steel or plastics plate or plates 3. In the case where the hood is cast from light metal, the steel plate or plates 3 are cast integrally therewith or thereon. If it is intended to use a plastics plate or plates instead of steel plate(s), this is secured by being bolted in a manner to be described hereinafter to the interior 2a of the hood 2. (The steel plate(s) 3 can also be bolted to the interior 2a of the hood 2 should this appear necessary or desirable for any reason).

Stringent requirements as regards the specific properties are placed on the material of the steel or plastics plates in order to distribute and disperse and at the same time largely absorb the residual kinetic energy of a projectile, missile, splinter or the like that has penetrated the hood 2.

Although the plate or plates 3 to be mounted on the inside 2a of the hood 2 should of course be relatively thin, they must at the same time possess suitable toughness and elasticity properties. Such properties can be obtained in a known manner by alloying in the case of steel plate(s). In addition to other steel alloys that are suitable for the aforementioned purpose, an alloy having for example the following composition is suitable: C < 0.1%; Sil%; Mn < =2%; Cr=17.... Ni=9 1 1.5%; Ti~5%xC; P~0.45%; S~0.035%; remainder: Fe. The tensile strength of such an alloy is for example of the order of magnitude of > 500 750 N/mm2.

If it is intended to use plastics plate(s) instead of steel plate(s), a suitable plastics material may be chosen from the polycarbonate range since this provides at least the required toughness and elasticity properties.

In order to join a steel plate to a hood 2 of light metal, according to Fig. 2, reinforcing hooks or clamps 4 are mounted in different planes to the steel plate 3, for example by welding or the like.

The free ends 4a of these hooks 4 serve to provide anchoring points in or during the casting of the hood 2. As a result of the different doefficients of expansion of light metal and steel, a type of shrinking effect occurs when the light metal casting is cooled, which ensures an intimate and positive bonding between the steel plate or plates 3 and the inner wall 2a of the hood 2.

Fig. 3 shows a steel or plastics plate 3 secured to the inside 2a of the hood 2 by means of a releasable securing means such as a bolt 5. In this embodiment, a projection 2b in which a thread 5a is machined out is cast on the inside 2a of the hood 2 at each attachment point in order to assist accurate positioning of the steel plate or the like 3. The steel plate 3 is secured in a known manner by means of a bolt 5 and washer 7. A plastics plate may in principle also be secured in a similar manner to the inside 2a of the hood 2.

Claims (9)

Claims

1. Apparatus such as turrets, gun carriages, armoured hulls, weapon platforms or the like for use on land or sea and of light metal construction, comprising a load-bearing outer part provided on its inner surface with a steel or plastics plate which distributes and disperses and largely absorbs residual kinetic energy of a projectile, missile, splinter or the like which penetrates the outer part in use.

2. Apparatus according to Claim 1, the plate that distributes and disperses and largely absorbs the residual energy comprising a relatively thin but tough high alloy steel.

3. Apparatus according to Claim 1, the plate that distributes and disperses and at the same time largely absorbs the residual energy comprising a tough elastic plastics material.

4. Apparatus according to Claim 3, the plastics being a polycarbonate.

5. Apparatus according to Claim 2, the plate being cast integrally with or on the inside of the load-bearing outer part.

6. Apparatus according to any of Claims 1-4, the plate being secured by releasable securing means to the inside of the load-bearing outer part.

7. Apparatus according to Claim 6, the releasable securable means comprising bolts.

8. Apparatus according to any of Claim 1, 2 and 5-7, the steel plate including a plurality of reinforcing hooks or clamps arranged in different planes which are cast integrally with the material of the load-bearing outer part when the latter is reinforced with the steel plate.

9. Apparatus according to any preceding Claim, there being a plurality of said steel or plastics plates on the inner surface of the loadbearing outer part.

1 0. Apparatus such as turrets, gun carriages, armoured hulls, weapon platforms or the like substantially as hereinbefore described with reference to and as shown in any of the drawings.

1 A vehicle including apparatus according to any preceding Claim.