The invention relates to “containerised” missile systems in which one or more missiles are supplied in and launched from a respective container or box, the container being adapted both for storage of the missile and to act as a missile launcher which redirects the missile motor efflux in the direction of launch. Such systems give a degree of versatility in that a land vehicle, ground station or ship, for example, can be relatively easily adapted to carry one or several of the containers. Generally, the containers are mounted to launch the missiles vertically but this is not essential. Also, for compactness, it may be desirable to store the containers horizontally, e.g. in a stack on or below a ship's deck.
A number of design difficulties associated with such systems concern the management of the efflux from the missile when it is fired. It is known for the mounting arrangement for a battery of containers to include a common plenum chamber and exit stack(s) with which the containers are able to communicate. This adds to the complexity of the mounting arrangement and possibly also the containers, since each must be provided with an openable door or the like to prevent interference with one missile by the efflux of another which has been fired.
The present invention aims to provide a container having improved efflux management compared with known systems.
Accordingly, the invention comprises a container for housing a missile and for having the missile fired therefrom, the container incorporating an integral efflux management system including duct means, deflector means for directing the missile efflux into the duct means, and closure means for maintaining the container normally closed while ensuring, on firing of the missile, that the duct means becomes open to allow exit of said efflux, in which the deflector means comprises a base-plate which is separated from said duct means and whose interior wall is so shaped to define therebetween a chamber having the shape of a flattened dome.
By way of example, the container can comprise an elongate box along the interior surface of which run ducts leading from the chamber located behind the missile, to the exit end of the container, which exit end is closed by a cover openable to allow exit of the missile from the container and the efflux from said ducts.
The purpose of the specially-shaped base plate is to ensure efficient missile efflux management. Compared with a true domed or hemispherical shape, the flattened shape of the chamber also allows a reduced container length without sacrificing efficiency.
The inventors have found that base plate pressures are very sensitive to chamber depth (i.e. missile nozzle exit to base plate separation). It is preferable for this dimension to be optimised for a given missile boost motor, in order to give acceptable base plate pressures while minimising container length.
The interior wall of the base-plate is rounded in order to ensure smooth, steady flow of efflux throughout the ducts and chamber, thereby preventing the occurrence of unstable corner vortices. Such vortices can periodically break away along the ducts, resulting in undesirable pressure pulses.
Preferably, the interior wall of the base plate is lined with an ablative coating.
The container could be of any convenient cross-sectional shape, for example, circular, square or rectangular, and could contain any number of ducts, as convenient.
At the missile exit end of the container, the ducts could be flared outwards, or deflector members could be provided, to deflect the missile efflux outwardly away from the container's longitudinal axis and hence away from the missile's flight path.
The closure means preferably comprises an inner frangible cover and an outer rough-handling cover. Alternatively, the outer cover could comprise a hinged door coupled to a pneumatic, hydraulic, spring-operated or pyrotechnic opening device and held closed by a releasable catch.
The container may be designed for single-shot operation or made more durable so that, with some refurbishment, it can be used a number of times.
Various known safety devices may be incorporated in the container, for example a water deluge mechanism.
Optionally, a valve, suitably located, could be provided for enabling nitrogen filling and gas pressure measurement.
An embodiment of the invention will now be described, by way of example only, with reference to the drawings, of which:
The container 1 shown in
Lifting lugs 2 fitted at one end may be arranged to give the subsidiary function of preventing the container 1 from rolling about when laid on the deck of a ship say, perhaps in a stack along with many other such containers. The container 1 may be mounted in more than one position from which firing of the missile may take place. This position could be with its axis vertical, horizontal or included in which case some suitable vertical or inclined fixing member is provided. The fixed mounting for the container might also comprise some form of cradle and such a cradle might allow for variation of the container axis direction.
Within the container 1 is a missile 3.
Strengthening frames 4 extend the length of the duct section 1a and strengthening ribs 5 are provided on the pedestal section 1c and base plate 1d.
The diffuser 1b is flared outwards in order to deflect missile efflux away from the missile's flight path.
The container is sealed, (at the diffuser end) by an inner frangible cover 6 and, covering this cover 6, an outer rough-handling cover 7. The cover 7 is intended to be removed manually say when the container 1 has been set-up in its position of use and/or at times when it is likely to be needed. The inner frangible cover 6 is burst or blown off just prior to missile firing by say a pyrotechnic rupture device. However, both covers are designed to allow for the possibility of inadvertent firing of the missile while it is held within the container. Being frangible, the cover 6 would be burst by the resultant gas pressure while the cover 7 could be so held in place that it also is ejected by the gas pressure.
The back or tail of the missile 3 lies at a position spaced from the other end of the container, which end is closed by the base plate 1d.
Referring now to
Each duct 8 is defined by a base wall 8a running parallel to and distanced from the container wall, and two side walls 8b which extend from respective edges of the base walls 8a. The distance between a pair of side walls 8b becomes greater with the distance from the base wall 8a. Each side wall 8b terminates in an outwardly-turned flange 8c which is fixed to the container wall. A base wall 8a of a respective duct 8 faces the base wall 8a of an opposite duct 8 and is spaced therefrom.
The missile is positioned in the space bounded by the four base walls 8a of the four ducts with its fins 3a extending between facing side walls 8b of adjacent ducts 8.
The container/missile arrangement can be assembled by locating the missile 3 within the pedestal section 1c, placing the duct section 1a over the missile 3 and making necessary connections to the pedestal section, and finally bolting on the 1d base plate to the pedestal section 1c.
The base plate 1d which is shown in plan and cross-section in
The function of the inner wall 10 is to deflect the missile efflux through 180°, back in the direction from which it arrived and into the ducts 8. The ducts 8 lead the efflux out of the container at the top i.e. in the same direction as the missile emerges. A protective coating of ablative (not shown) material may be applied to all or selected parts of the exposed surfaces of the ducts 9 and/or the inner wall 10.
During launch, the missile boost motor jet efflux is directed at the inner wall 10 of the base-plate 1d. The inner wall 10, which reverses the direction of the efflux is therefore subjected to a total force equally to twice the thrust of the motor. The strengthening ribs 5 provided on the outer wall of the base-plate 1d serve to limit any resulting distortion of the base-plate and possible separation of the ablative coating.
Number | Name | Date | Kind |
---|---|---|---|
2802399 | Little | Aug 1957 | A |
2903124 | Carver | Sep 1959 | A |
3014410 | Anderson | Dec 1961 | A |
3135163 | Mechlin et al. | Jun 1964 | A |
3769876 | Hass et al. | Nov 1973 | A |
4498368 | Doane | Feb 1985 | A |
4934241 | Piesik | Jun 1990 | A |
5012718 | Miller | May 1991 | A |
5194688 | Piesik | Mar 1993 | A |
5239909 | Bell et al. | Aug 1993 | A |
5322002 | Miskelly, Jr. et al. | Jun 1994 | A |
Number | Date | Country |
---|---|---|
0 473 498 | Mar 1992 | EP |
2 555 725 | May 1985 | FR |
1267679 | May 1968 | GB |
1575044 | Sep 1980 | GB |
2142741 | Feb 1984 | GB |
2 140 898 | Dec 1984 | GB |
2145203 | Mar 1985 | GB |