DE4101960A1 - Guided missile structure - has inflatable air-bag at rear end which reduces air resistance and increases range of missile - Google Patents

Abstract

A guided missile (10) with a cropped rear end is fitted with an inflatable air bag (22) and a gas generator for inflating the bag. When the missile is in flight the air bag is inflated and occupies the region of stagnant flow which arises at the rear end of the missile. The device reduces the air resistance of the missile and increases the missile range. The air bag is initially folded into a small space at the rear end of the missile and so reduces the storage space required in comparison with missiles with rigid rear ends. USE/ADVANTAGE - Guided missile with increased range and reduced storage space.

Description

The invention relates to a device according to the Oberbe handle of claim 1 specified features.

DE 31 42 802-A1 describes a missile with one more or less known cut off floor. To Range increase it is necessary to have an undesirable to reduce or eliminate soil drag. For this there is a nozzle at the tail end of the missile provided from the two combustion gases to avoid a soil vacuum that increases soil drag stream. Such a device is suitable for Nozzle arrangement especially for self-propelled missiles, for example a missile or a projectile; she is ever yet too space-consuming and too complicated when it comes to the ground suction resistance when the flight is not self-propelled bodies, such as one from a cargo floor ejectable submunitions.

From DE 26 45 419-A1, a shaped charge projectile is known which contains, for example, a bellows in front of a hollow charge arranged on the bottom, on which a gas generator is arranged, through which the volume of the bellows is inflatable beyond the projectile diameter. As a result, and due to an unfavorable diameter / length ratio, for example ≧ 1 , the bellows is only able to stabilize and brake, for example, a shaped charge mine during the fall movement. This projectile stabilization and braking measure is therefore not suitable for increasing the range.

In contrast, it is an object of the invention, a Vorrich to create the space-saving and simple structure and is still able to withstand the ground suction decrease significantly.

This task is solved by the in the characteristic Part of claim 1 specified features.

Advantageous embodiments of the invention are shown in the Characteristics of the subclaims.

The invention is based on a Darge in the drawing presented embodiment explained in more detail.

It shows

Fig. 1 a flow missile with a surrounding air and a rear dead water region,

Fig. 2 is a missile with a the dead water region fills the air bag,

Fig an enlarged view of the missile tail shown in FIG. 1. 3,

Fig. 4 is an enlarged view of the inflated air bag shown in Fig. 2.

The missile 10 shown in FIG. 1 is completely blunt on the tail side and therefore causes a dead water area 12 known in fluid mechanics behind the missile (literature: Willi Bohl, "Technical Fluid Mechanics", Vogel Verlag 1971 , pages 126 to 128) . This dead water area 12 is known as an area of not inconsiderable energy dissipation, and significantly causes an increased flow resistance and thus also an increased drag coefficient. As a result, in a missile 10 with such a blunt missile tail, the flight range is shorter than in the case of an aerodynamically formed tail.

Fig. 1 illustrates a direction of flight 11 in Rich device 15 counter-flowing air flow 14 with the dead water area 12 created behind the blunt tail end. The dead water area 12 encloses a swirled Darge flow area behind the detachment line of the umström th missile 10 , in which, in addition to a strongly delayed basic flow, a swirling flow form is present. The outer flow 14 is pushed away from the outer contour of the missile 10 . This, largely caused by boundary layer separation of the air flow 14 formation of the dead water area 12 , is a major cause of the pressure resistance present here.

The dead water area 12 begins immediately behind the comparatively sharp outer edge of an on the missile shell 18 ( Fig. 3) locked retaining cover 26 for an air bag 22 , and is from the missile 10 detached and very slim and streamlined converging merging Air flow 14 limited.

So that this dead water area 12 does not arise or is largely avoided, the invention provides for the space filled by the dead water area 12 to be filled with an air bag 22 which can be filled with gas 20 (FIGS . 2 and 4). The missile 10 thereby adopts a streamline shape adapted to the non-detached air flow, as a result of which flow resistances through the ground suction are reduced to a minimum.

This arrangement makes it particularly advantageous to achieve stable flight behavior and a range increase, for example in the case of an ejectable from a cargo floor (not shown) and provided with tail fins 34 , 36 , not self-propelled submunition 10 .

In such a submunition 10 , the air bag 22 can be filled with gas by, for example, two gas generators 24 arranged on the missile floor 16 briefly, immediately after leaving the carrier projectiles. The generated by the gas generator 24 gas 20 loads the present in FIG. 3 in a rear storage space 30 of the submunition 10 NEN and in a storage length 1 held by the lid 26 NEN air bag 22 . During the filling process, the cover 26 is loosened by the increasing air bag 22 from the missile case 18, so that the air bag 22, the dead water area can fill 12th

The air bag 22 made of known materials, for example textile fabrics, is flanged on the outside at the rear of the missile 10 to maintain a stable streamlined shape via fastening means 32 .

Reference symbol list

10 missiles
11 Direction of flight
12 Dead water area
14 air flow
15 flow direction
16 missile floor
18 missile shell
20 gas
22 Air bag
24 gas generator
26 cover
28 folds
30 storage space
32 fasteners
34 empennage wings
36 empennage wings
1 stowage length

Claims (3)

1. Device for reducing the ground suction resistance of a missile ( 10 ), characterized by a gas ( 20 ) fillable air bag ( 22 ), which - filled - assumes the shape and size of a dead water area ( 12 ) of the missile ( 10 ) . 2. Apparatus according to claim 1, characterized in that at least one gas generator ( 24 ) for filling up the air bag ( 22 ) is arranged on the bottom ( 16 ) of the missile ( 10 ). 3. Apparatus according to claim 2, characterized in that the air bag ( 22 ) on the bottom ( 16 ) of a submunition ( 10 ) is arranged.