US3747533A

US3747533A - Short trajectory missile

Info

Publication number: US3747533A
Application number: US00201521A
Authority: US
Inventors: R Rossmann
Original assignee: Werkzeugmaschinenfabrik Oerlikon Buhrle AG
Current assignee: Rheinmetall Air Defence AG
Priority date: 1970-12-08
Filing date: 1971-11-23
Publication date: 1973-07-24
Anticipated expiration: 1990-07-24
Also published as: DE2155467A1; BE775798A; FR2114879A5; DE2155467B2; GB1319923A; CH532240A

Abstract

Short trajectory missile comprising a missile body and a missile head separating during flight. A part of the missile head such as the front end thereof is formed of a material capable of melting due to the friction of air resistance.

Description

United States Patent 1191 1111 3,747,533 Rossmann 11 July 24, 1973 SHORT TRAJECTORY MISSILE [56] References Cited [75] Inventor: Rudolf Rossmann, Zurich, UNITED STATES PATENTS Switzerland 2,987,999 6/1961 Robinson, Jr. et al 102 493 3,106,162 10/1963 Hagerty 102/105 [73] Assgnee' gg f fzl gxf g'g g gg 3,496,869 2 1970 Engel 102/93 3,580,179 5/1971 Gawlick et al l02/92.6 Switzerland i 1 Filed: 23, 1971 Primary Examiner-Verlin R. Pendegrass [21] AppL NO 201,521 AttorneyE. F. Wender0th,.leffrey Nolton e! ill.

[30] Foreign Application Priority Data ABSTRACT Dec. 8, 1970 Switzerland 18326/70 Short trajectory missile comprising a missile body and a missile head separating during flight. A part of the Cl missile head such as the front end] thereof is formed of [51] Int. Cl. .4 F42b 13/20 a material capable of melting due to the friction of air [58] Field ol Search... lO2/49.4, 93, 92.6, resistance.

' vill lIII PATENIEDJuLwm SHEET 1 [1F 3 Fig. J

RUDOLF ROSSMAN'N, Inventor PATENIEDJULMISYS SHEET 2 0F 3 un I l l I I,

'RUDOLF ROSSMANN, Inventor mmmw Attorneys PAIENTEDJuL24|91s SHEET 3 OF 3 RUDOLF ROSSMANN, Inventor 1r) IDIMM 1' Attorneys vlf(((( SI-IORT TRAJECTORY MISSILE BACKGROUND OF THE INVENTION The present invention relates to a short trajectory missile with a missile body and a missile head which separates from the body during the flight of the missile. A missile of this kind should have the same external ballistic characteristics for practice purposes in the range or area of utilization as the or actual type corresponding thereto. In the braking zone of the flight of the missile, means or agents should become effective to alter the ballistic characteristics of the missile in such a way that the flight trajectory will be considerably reduced in comparison with that of the effective or actual missile.

With a known missile of this type, the missile head is held by balls which are introduced into the missile head, into which a groove of the missile body projects and is held by a pin. At the time of firing a safety bolt is sheared off and the pin is thrown backwards, so that the balls become free. However, in the area of utilization these balls are pressed outwardly into the aforementioned groove by centrifugal force. Following a reduction in the centrifugal force, the balls fall out of the groove in the braking area, and the missile head is thrown forward by a spring, as a result of which the missile head and missile body rapidly loose speed and fall to the ground.

A disadvantage with this missile is that a large number of components are required for the separation of the missile head, as a result of which the manufacture of the missile requires considerable expenditure in time and money.

SUMMARY OF THE INVENTION It is an object of this invention to create a short trajectory missile with a very simple and cost-saving design, such missile having the same external ballistic charcteristics in the range or area of utilization as the effective or actual missile corresponding thereto.

In accordance with the invention there is provided a short trajectory missile comprising a missile body and a missile head capable of separating during the flight of the missile, wherein a part of the missile head comprises material capable of melting due to the friction of air resistance. In a particularly advantageous embodiment, a front end of the missile head consists of a material capable of melting as a result of the friction of air resistance, and the missile head has a hollow space, so that after the melting of the aforementioned front end, the missile head bursts as a result of a momentary increase in air pressure into the hollow space and is separated from the missile body.

The advantages achieved with the invention lie in the fact that the missile has a very simple construction, whereby the flight range can be determined by a corresponding dimensioning of the missile head. The exter- 'nal ballistic characteristics of the missile can be matched to those of the effective or actual missle by weight and shaping of the missile body and missile head.

BRIEF DESCRIPTION OF THE DRAWINGS The invention will now be described by way of example with reference to the accompanying drawings in which:

FIG. ll shows a longitudinal section through the short trajectory missile;

FIG. 2 shows the short trajectory missile of FIG. l but without protective hood and plastics sheath during flight in the area of use; and

FIG. 3 shows the short trajectory missile of FIG. 2, without the separated missile head during flight in the braking zone.

DETAILED DESCRIPTION OF THE INVENTION Referring to the drawings FIG. 1 shows a missile body I provided at its front end with an axially drilled channel 2 into which extend four radially drilled holes 3, which are mutually perpendicular to each other. The missile body ll has an annular front surface 4, which is engaged by annular ridge 6 of a missle head 5, the missile head 5 projecting into the channel 2. The missile head 5 tapers to a front end 8 and has an interior hollow space 7 opening rearwardly into channel 2. The missile head 5 is thus hollow and is made from a material capable of melting as a result of the friction of air resistance, in this case plastic material. The missile body I is surrounded by a plastic sheath 9, which at its rear end has a guiding and sealing band 10. A protective hood Ill surrounds the missile head 5 and the front end of missile body l and is secured in an annular groove 112 of the plastic sheath 9.

The missile is shown while in flight in the area of utilization in FIG. 2, whereby the air L striking the missile head 5 creates a ram or pressure point P and flow lines S andS FIG. 3 shows the missile while in the braking zone whereby the unfavourable flow ratios are represented by flow lines S and 8,.

After firing, when the short trajectory missile has left the barrel, the protective hood 11 and plastic sheath 9 are separated from the missile body by centrifugal force. The missile, including the missile head 5, now posses a favourable, low resistance external shape, creating flow lines S, and S (see FIG. 2). At ram point P the front end 8 of the missile head undergoes, as a result of the friction of air resistance, an increase in temperature, which, for example, at a missile velocity of 1,300/m/s is about 850 C and causes the missile head to melt. The wall thickness of the hollow missile head 5 is dimensioned so that the possibility of melting through in the area of utilization :is avoided, that is to say, that the optimum missile shape is maintained in the area of utilization.

On entry of the missile into the braking zone, the melting process has progressed sufficiently that the front end 8 of missile head 5 is melted completely through. The opening occuring as a result of this brings out a displacement of ram point P rearwardly into hollow space '7. The momentarily effective pressure increase therefore brought about in hollow space 7 causes the missile head 5 to burst and separate from missile body ll. The air L flowing into channel 2 is directed radially outwardly through radial holes 3, as a result of which a turbulent flow develops=on the external surface of the missile body. As a result the flow characteristics of the missile become very unfavourable, as shown in FIG. 3 by flow lines 8, and 8,, and air resistance is increased very considerably. The missile body is thus braked very quickly so that the flight trajectory is tremedously reduced.

In this embodiment, the four radial drillings 3 are arranged mutually perpendicular to each other, or in other words, they are arranged symmetrically in relation to a plane running through the longitudinal centre line A of the missile. With an asymmetrical arrangement in relation to the aforementioned plane of at least two radial drillings, the stability of the missile body is additionally disturbed in the braking zone. A resultant movement similar to a pendulum movement occurs, so that the flight trajectory is even further reduced.

I claim: 1. A short trajectory training missile comprising: a missile body; a missile head separably attached to the forward end of said missile body; said attached missile body and missile head having an exterior shape to produce external ballistic characteristics within the range of desired utilization identical to those of a corresponding actual missile; said missile having means for causing said missile head to separate from said missile body upon passage of said missile from said range of utilization, thereby substantially altering the ballistic characteristics of said missile, and for imparting a rapid braking of the trajectory of said missile; said means comprising a hollow space on the interior of said missile head, and a forward end of said missile head closing said hollow space, said forward end being formed of a material capable of being melted through by the friction of air resistance upon the passage of said missile from said range of utilization, whereby said hollow space is subjected to an instantaneous air pressure increase, and said missile head being formed of a material capable of bursting under the force of such interior air pressure increase.

2. A missile is claimed in claim 1, further comprising an axial channel extending into said missile body from the forward end thereof, said missile head extending into said axial channel, said hollow space communicating with said axial channel and at least one radial hole extending outwardly through said missile body from said axial channel to the exterior of said missile, whereby when said forward end of said missile head melts, air passes through said hollow space, inJo said axial channel, and outwardly through said at least one radial hole, thereby creating increased rapid braking of the trajectory of said missile.

3. A missile as claimed in claim 2, wherein said at least one radial hole comprises a plurality of radial holes symmetrically spaced around said missile body.

4. A missile as claimed in claim 2, wherein said at least one radial hole. comprises a plurality of radial holes asymmetrically spaced around said missile body.

5. A missile as claimed in claim 2, wherein said at least one radial hole comprises four radial holes spaced around said missile body.

Claims

1. A short trajectory training missile comprising: a missile body; a missile head separably attached to the forward end of said missile boDy; said attached missile body and missile head having an exterior shape to produce external ballistic characteristics within the range of desired utilization identical to those of a corresponding actual missile; said missile having means for causing said missile head to separate from said missile body upon passage of said missile from said range of utilization, thereby substantially altering the ballistic characteristics of said missile, and for imparting a rapid braking of the trajectory of said missile; said means comprising a hollow space on the interior of said missile head, and a forward end of said missile head closing said hollow space, said forward end being formed of a material capable of being melted through by the friction of air resistance upon the passage of said missile from said range of utilization, whereby said hollow space is subjected to an instantaneous air pressure increase, and said missile head being formed of a material capable of bursting under the force of such interior air pressure increase.

4. A missile as claimed in claim 2, wherein said at least one radial hole comprises a pluralIty of radial holes asymmetrically spaced around said missile body.