US3727569A

US3727569A - Missile

Info

Publication number: US3727569A
Application number: US00790976A
Authority: US
Inventors: H Johnson; H Silk
Original assignee: US Department of Navy
Current assignee: US Department of Navy
Priority date: 1959-02-03
Filing date: 1959-02-03
Publication date: 1973-04-17
Anticipated expiration: 1990-04-17

Abstract

1. A weapon for use against a target submarine, said weapon comprising, in combination: an ordnance apparatus effective to operate against a submerged target submarine when delivered to a suspect water area; an airframe severably secured to said ordnance apparatus, said airframe including reaction propulsion means to project said weapon from a launcher and into a ballistic trajectory directed toward said suspect water area; means including a presettable timing device for severing, separating and jettisoning the airframe from said ordnance apparatus at a preselected instant during airflight; deceleration means secured to said ordnance apparatus and operatively associated with said airframe to become effective upon airframe separation and in response to airframe separation; and means for jettisoning said deceleration means upon water entry of said ordnance apparatus.

Description

waited States Pate Johnson et a1.

[ MISSILE [75] Inventors: Harold G. Johnson, Trenton, N. I.;

Harry Silk, Washington, DC

[73] Assignee: United States of America as represented by the Secretary of the Navy [22] Filed: Feb. 3, 1959 [21] Appl. No.: 790,976

[56] References Cited UNITED STATES PATENTS 2,390,677 12 1945 Alkan ..244/14 2,859,722 11/1958 Myers ..244/14 2,539,643 1/1951 Smythe... 14/20 431,210 7/1890 Lassoe .114/20 2,995,319 8/1961 Kershner et al. ..244/14 2,992,794 7/1961 Boyd 2,941,764 6/1960 Lee et al. 2,880,687 4/1959 Kilvert... 2,870,710 1/1959 Miedel 2,824,711 2/1958 Porter 1 1 Apr. 17, 1973 OTHER PUBLICATIONS Aviation Week, Feb. 24, 1958, pp. 56-57. Astronautica Acta, Vol. 3, No. 1, 1957, p. 70.

Primary Examiner-Benjamin A. Borchelt Assistant ExaminerThomas I-l. Webb AttorneyQ. Baxter Warner and V. C. Muller EXEWLARY CLAIM l. A weapon for use against a target submarine, said weapon comprising, in combination: an ordnance apparatus effective to operate against a submerged target submarine when delivered to a suspect water area; an airframe severably secured to said ordnance apparatus, said airframe including reaction propulsion means to project said weapon from a launcher and into a ballistic trajectory directed toward said suspect water area; means including a presettable timing device for severing, separating and jettisoning the airframe from said ordnance apparatus at a preselected instant during airflight; deceleration means secured to said ordnance apparatus and operatively associated with said airframe to become effective upon airframe separation and in response to airframe separation; and means for jettisoning said deceleration means upon water entry of said ordnance apparatus.

PATENTEU APR 1 7 I973 SHEET 1 BF 5 ATTORN'EY'S PATENTEDAPR 1 H973 v 3 727, 569

SHEET 2 OF 5 INVENTORS.

HAROLD G. JOHNSON HARRY SILK ATToRNEY.

PATENTEDAPR1 71973 SHEET 3 OF 5 INVENTORS HAROLD G. JOHNSON HARRY SILK BY ATTORNEYS.

PATENTEBAPR 1 71973 SHEET L; []F 5 INVENTORS. HAROLD G. JOHNSON HARRY SILK ATTORNEYS.

PATENTEDAPR 1 71973 SHEET 5 [IF 5 INVENTORS. HAROLD G. JOHNSON HARRY SILK Q 15L Mal u ATTORNE'YS,

MISSILE The invention described herein may be manufactured and used by or for the Government of the United States of America for governmental purposes without the payment of any royalties thereon or therefor.

This invention relates to ordnance apparatus, and and more particularly to a self-propelled missile intended principally for use by destroyers or other warships against enemy submarines.

It is of course the immediate purpose of anti-submarine operations to effect delivery and detonation of explosive charges within lethal distance of the enemy submarines under attack. Of present interest in such respect are the shipborne anti-submarine weapons of prior art homing torpedo type, these being launched from tubes, or catapulted into the water a short distance from the ship, such weapons in any event being characterized by an entirely or principally underwater mode of transport to the suspect target area. It might seem that such anti-submarine homing weapons would be particularly efficacious at all times because of their target-seeking, pursuing and attack capabilities. Homing torpedoes nevertheless present limitations which are bound to seriously reduce their effectiveness in certain tactical situations likely to be encountered in actual sea warfare. Specifically, an enemy submarine can be expected to approach a target ship closely enough to place it within range of torpedoes carried by the submarine, but not so closely as to place itself within easy reach of depth charges or homing torpedoes carried by that target ship or by escort destroyers or other warships. Prior art shipborne anti-submarine torpedoes are at an immediate disadvantage under such circumstances, since the range at which a homing torpedo can detect the presence and direction of a target submarine is no more than a small fraction of the stand-off range from which a submarine can fire its spread of torpedoes. In an attempt to overcome this difficulty, advanced types of ship-launched anti-submarine torpedoes have been designed to first proceed along a predetermined course toward the suspect area, then to enter some type of scanning search for the target, followed by switchover to a homing and pursuit phase if and when the target submarine is in fact detected. Despite such automatized sophistication of modern anti-submarine homing torpedoes, they will not have good kill probability when employed by vessels under circumstances as indicated above, due to inherent limitations of the torpedo itself as to speed, total range and target detection range, but particularly as to relatively long swim-out time which will generally enable the target submarine to have escaped from the target detection field of the ship-launched torpedoes by the time they arrive at the originally suspect area.

In accordance with the present invention this serious difficulty is now overcome by providing an anti-submarine weapon which is rocket-launched from a vessel to travel at high speed above water toward a suspect target area, and which delivers an anti-submarine payload to that area by means which decelerates the payload prior to water entry in order to overcome malfunction problems which would otherwise be occasioned by high-speed water impact forces.

The primary object of the present invention, therefore, is to provide an improved anti-submarine weapon, more specifically, to provide a missile which effects high-speed above-water delivery of an anti-submarine payload to a suspect target area, reduces the waterentry speed, and frees the said payload to engage in its underwater operations.

Another object is to provide an anti-submarine weapon which is self-propelled above water in an initially ballistic path toward a suspect target area.

A further object of the invention is to provide an anti submarine weapon having an increased delivery range and a shortened delivery time.

These and other objects and many of the attendant advantages of this invention will be readily appreciated as the same becomes better understood by reference to the following detailed description when considered in connection with the accompanying drawings wherein:

FIG. 1 depicts in general manner the above-water operational characteristics of an anti-submarine weapon in accordance with the present invention;

FIG. 2 illustrates the overall configuration of a prototype version of the weapon, comprising a homing torpedo type of payload severably secured to an airframe having a rocket engine;

FIG. 3 is a fragmentary view of the weapon, partly in section, showing several details in the region of the juncture between the rocket motor, airframe and payload torpedo;

FIG. 4 illustrates the manner in which airbrake members of the airframe release and open away from the payload torpedo after a preselected period of airflight;

FIG. 5 is a sectional view on the line 5-5 of FIG. 3, showing a banding arrangement which secures the airbrake members of the airframe to the payload torpedo;

FIG. 6 illustrates one of the explosion units underlying the banding and for rupture thereof at a predetermined instant after launching;

FIG. 7 is a perspective view of the airframe with the air-brake members removed for clarity;

FIG. 8 details the manner in which airframe thrust struts engage and bear against the fixed fins of the payload torpedo;

FIG. 9 is an end view of airframe structure at line 9 9 of FIG. 3;

FIGS. 10 and 11 detail an airbrake member and its association with the airframe and the payload torpedo;

FIG. 12 is an end view of the airframe, taken along direction line 12 in FIG. 2; and

FIG. 13 is a schematic circuit diagram of the separation fire control apparatus.

Referring first to FIG. 1 of the drawing there is diagrammatically indicated the general configuration of the anti-submarine weapon 15 and the sequence of events which occur during its airflight and at waterentry of its payload l6. Described later in greater detail, the weapon 15 comprises a Wingless airframe 17, the payload 16 extending from the forward end of the airframe and severably joined thereto, propulsion means 18 which is preferably a rocket engine supported in the stern portion of the airframe, means for releasing, separating and jettisoning the airframe from the payload at a predetermined instant after launching, a packed parachute 19 having its shroud lines running to the stem end of the payload and arranged to open and deploy during separation of the airframe, and a parachute coupling release mechanism 20 which frees the payload from the parachute at water-entry.

Impelled by rocket propulsion, the weapon projects itself from a launcher 21, which is preferably trained at an angle of substantially 45, and pursues an essentially ballistic trajectory 22 at relatively high speed until, at a predetermined instant associated with the desired range, explosive sundering means carried by the weapon are detonated, as indicated at 23, to initiate separation of the airframe from the payload. By such means, hinged airbrake members 24 of the airframe are unlocked and released from the payload, opening as indicated at 25 and thus retarding the airframe so that it is separated and jettisoned from the payload. A parachute-opening lanyard 26, secured at one end to the airframe, and at the other end to the canopy 27 of the packed parachute coupled to the payload, thus comes under tension and breaks as the parachute pulls out, the airframe 17 then tumbling free as indicated. The parachute 27 deploys, and the payload 16 continues its airflight along a non-ballistic path toward the suspect area, the payload descending at a comparatively steep angle, as indicated, but with decrease in speed because of parachute drag. At water-entry of the payload 16, the reduction in pull force then experienced by the shroud lines 28 causes the coupling mechanism 20 to unlock, releasing the parachute 27 and enabling the payload 16 to proceed unimpeded in its underwater phase of attack against the target submarine 29.

It will be understood in view of the foregoing that any operational system in which the anti-submarine weapon disclosed herein would be employed must of course function to detect and to determine target direction and range information, such that a separation timing circuit in the weapon itself and the training direction of the weapon launcher may be suitably set to result in delivery of the weapon to the suspect or predicted target area. This presetting may be accomplished simply by operator control before launching; in its most advanced version, such a system may be fully automatized to continuously provide training orders for the weapon launcher, and timing orders for the weapon itself, so that the weapon is always suitably set and ready to be fired at any instant in the period during which the launching vessel is at suitable position and range relative to the target submarine to be attacked. Further description of the several elements of a complete system, however, is not included herein since the system may be entirely conventional and since details thereof are unnecessary to an understanding of the present invention which is concerned with the weapon per se. It should also be understood that the representation of launcher apparatus at 21 in FIG. 1 is simply schematic, and that the anti-submarine weapon indicated as launched therefrom is shown in exaggerated relative size for ease of illustration.

The anti-submarine weapon 15 is here described in terms of a prototype version shown in FIG. 2, the payload 16 in this instance being an acoustic homing torpedo which may be conventional in all respects, except for minor adaptive modifications as to external elements for attachment of the airframe 17 as will be detailed, and as to launching lugs 32 which, with one or more additional lug members 33 on the airframe, enable the weapon to be supported from overhead rail members of suitable launcher apparatus and to be guided along said rail members during self-projection of the weapon from the launcher apparatus. Thus, the torpedo may if desired be of type which is self-energizing by means of depth-responsive hydrostat switch assemblies which complete electronic, steering control and propulsive circuits when the torpedo has reached a depth of say 18 feet after water-entry, or of other type wherein the electronic and steering control circuits are energized, at some instant prior to water entry, by a timing mechanism or by other means.

Referring now to the weapon as illustrated in FIGS. 2, 3 and 4, the stern portion of the airframe in this instance is constructed as a sleeve section 34, within which the rocket engine 18 is supported as shown, in preference to an alternate arrangement wherein the rocket engine would itself form a body element of the airframe. The rocket thrust may be transmitted to the sleeve section of the airframe through the forwardly located shoulder of rocket nozzle 35, as indicated, or by any other arrangement such as through a thrust shoulder generally provided on the rocket chamber. In order to provide improved stability and to reduce ballistic dispersion, the weapon is provided with a cruciform arrangement of fins 36 which may be of trapezoidal planform, these fins being secured to the sleeve section 34, for example simply by riveting as indicated, and similarly to a retaining ring structure 37, better detailed in FIG. 12, which serves to clamp against the neck portion of rocket nozzle 35 and to thus hold rocket engine 18 in place within sleeve section 34. Referring again to FIGS. 2, 3 and 4, central section 40 of the airframe in this instance is of frusto-conical configuration and is fitted with a removable panel 41 which provides access to various components, later detailed, enclosed by the central section 40. Four struts 42, secured to and protruding from the central section of the airframe to bear against the cruciform arrangement of torpedo fins 43, serve to take the thrust compression loads resulting from the acceleration forces imposed by rocket engine 18. Aligned engagement of the thrust struts 42 with the torpedo fins 43, against which they must bear, is provided, and maintained when the airframe is banded to the torpedo as will be described, by means of metal dowels 44 which may be press-fitted into the strut ends 45 and received in the oppositely positioned holes in the torpedo fins 43, as detailed in 7 FIG. 8. For the purpose of joining the airframe to the payload torpedo, and also for later enabling separation of the airframe from the remaining missile structure at some instant during the airflight phase, the forward part of the airframe includes members 24 hinged to the central section 40, as shown in FIGS. 2, 3 and 4. These members 24 are clamped against the payload torpedo and so maintained, by banding 46, until the banding is automatically severed, as will be described, at which time the hinged members 24 are released to open away from the payload torpedo, as best shown in FIG. 4, to serve as airbrakes for separating, retarding and jettisoning the airframe as has been indicated.

When the hinged members 24 are closed toward the torpedo and bound thereto by means of the banding 46, the airframe is drawn tightly against the payload torpedo by means of the roller brackets 47, mounted upon the hinged members 24, which engage with the mating fittings 48 secured to the torpedo, as detailed in FIGS. and l 1. Until separation time, the airbrake members serve as a fairing between the payload torpedo and the central section 40 of the airframe. To insure that the airbrake members 24 will not be prevented, by air slipstream forces, from opening when the banding is severed, the weapon includes ejection springs 49 under compression between the airbrake members and the torpedo, as shown in FIGS. 3, 4 and 10, these ejection springs being secured to bracket members 50 mounted upon the inner surfaces of the airbrake members and seating upon pads 51 mounted upon the torpedo.

The airbrake members 24 are secured to hinge assemblies 54, as also shown in FIG. 10, the hinge assemblies including shearing blades 55 for purposes which will appear. Best detailed in the perspective view given in FIG. 7, (which view is simplified by omission of the airbrake members shown in other figures), the hinge assemblies 54 pivot upon pins 56 carried by arms 57 which extend into and are secured by any suitable means to the forward end of central section 40. Shearing blades 55 and hinge arms 57 project through accommodating slots formed in a generally conical diaphragm 58 which is secured to the forward end of central section 40, the blade and diaphragm arrangement also being shown in FIGS. 3 and 10. By way of examples, blades 55 may be made of commercial sheet steel, say A inch thick, tapered to provide a blunt shearing edge; diaphragm 58 may be formed of a suitable thickness of sheet metal, say No. 14 gauge (0.075 inch) low carbon steel. By such means, the shearing action which takes place as the airbrakes open (FIGS. 1 and 4) and experience large aerodynamic forces, at the relatively high speed provided by rocket propulsion, absorbs sufficient energy to provide retardation of airbrake opening. Except for this blade and diaphragm arrangement, or equivalent retardation means, the airbrakes may otherwise open much too quickly and tend to break off, in any event failing to suitably decelerate the airframe during airbrake opening, leading to possible interference with parachute deployment and consequently to weapon malfunction.

Packed parachute 19, and the coupling release mechanism to which the parachute shroud lines are secured, may be of any suitable type normally intended for use with aircraft-launched torpedoes. While thus conventional and therefore not further detailed, it may be noted that in the embodiment illustrated in FIG. 3, member 59 of the coupling mechanism 20 is to be understood as threadedly engaging a stub extension of the propeller shaft to which propeller hub 60 is secured, and that the parachute shroud lines are secured to the separable mating member 61 of coupling mechanism 20. For the purpose of unfolding or extracting the packed parachute when the airframe separates from the torpedo as has been described, the parachute static line or lanyard 26 is anchored to a clevis member 62 which is mounted upon conical diaphragm 58 in alignment with a central opening therein, as shown in FIGS. 3 and 9.

While the hinged airbrake members 24 may be severably secured to the payload torpedo 16 by means of a series of explosive bolts such as have been used in other ordnance devices, a severable banding arrangement as detailed in FIGS. 5 and 6 is preferred since rupture of the banding at any point therealong will definitely release all of the airbrake members and substantially simultaneously. In this instance, a continuous band 46, say of stainless steel, is double-wrapped over the forward ends 63 of the hinged airbrake members 24, tightened thereagainst and over say a pair of explosion units 64 containing small explosive charges in the form of electric primers or detonator caps 65, and is so maintained by any suitable clamping means 66 until, at the time the detonator caps are fired by means as next described, the banding is ruptured at the explosiondirecting slits 67 provided in the explosion units 64.

Each explosion unit 64 is bored as shown to accept the explosive primer 65, in this instance an easily available commercial type identified as Hercules No. 6 Vibracap and having a 2-ohm electrical firing element. The primer 65 is encased in explosion unit 64 and retained in position by means of an obturator member 68 which threadedly engages the explosion unit 64, the electrical leads 69 of the primer extending through an aperture provided in the outer end of the obturator member 68, thence to the separation fire control assemblies next described.

The separation fire control assemblies 72, contained within central section 40 of the airframe as indicated in FIG. 3, may be of any type adapted to provide an adjustable predetermined delay between the weapon launch instant and the instant at which it fires the detonator caps 65 to separate the airframe from the payload torpedo. These assemblies 72 may consist of entirely conventional elements, such as those briefly described in connection with a typical fire control circuit as given in FIG. 13, wherein the separation fire control assembly 72 begins charging capacitor 73 very soon after the weapon is launched, and at a later instant closes switch 74 to complete the electrical circuit between capacitor 73 and detonator cap 65. Switch 74 here forms part of and is controlled by a timing device 75 such as employed for flare fuzes, generally of clockescapement type adapted to be pre-set to effect its switch-closing operation at any desired time-interval after release of the escapement mechanism to initiate its timing function. Such release may be accomplished by the simple yet effective conventional arrangement which employs an escapement-unlocking pull-wire 76 as indicated at one of the assemblies in FIG. 3, in this instance operated at missile-launching by means of a lanyard 77 anchored to the launcher (not shown). As a safety measure, the capacitor charging circuit includes an arming switch 78 forming part of a conventional acceleration-responsive device 79, preferably of the type which does not close its arming switch 78 until the weapon experiences a sustained acceleration, say 106 for a period of I second, which values are normally exceeded in the described embodiment. Capacitor 73 then charges to substantially the voltage delivered by 'source 80, charging resistor 81 being of very low ohmage compared to the protective bleeder resistor 82. The circuit element values are not critical but, by way of example, capacitor 73 may have a value of 2 microfarads, charging resistor 81 may be 0.1 megohm, bleeder resistor 82 may be 44 megohms, and source may deliver volts to the charging circuit. The

separation fire control assemblies 72 are provided in duplicate as shown in FIG. 3 and, as indicated by the schematic given in FIG. 13, separately control the pair of explosion units 64 in order to improve reliability of the weapon as to opening of the airbrake members at the desired instant.

Referring again to FIG. 3, the shield 85 is provided to protect principally the separation fire control units against damage from the elevated temperatures of the rocket engine, and may comprise an insulating materia1, say glass wool, housed in an aluminum pan 86 located as shown and facing toward the rocket engine. The electrical leads from the igniter assembly 87 of the rocket engine terminate at a connector 88 mounted on the central section 40 of the airframe, connector 88 being of conventional type adapted to mate with a breakaway connector, associated with the launching apparatus, through which ignition voltage may be supplied as required to detonate the igniter charge to in itiate burning of the solid-propellant grain 89, thus firing the weapon. Rocket engine 18 may be of conventional JATO type ordinarily used for boosting aircraft power and acceleration at take-off, these rocket engines being available with various burning time and total impulse characteristics such that a suitable selection can be made to provide a desired maximum range for the weapon. Such range is principally dependent upon the thrust and impulse characteristics of the rocket engine, the weight of the complete weapon, and the drag of the weapon prior to separation time. By way of example, employment of a JATO unit weighing approximately 260 pounds and designed to deliver about 25,000 lb-secs total impulse over a period of 2.2 seconds, in a prototype anti-submarine weapon, as described, having a total weight of approximately 1,200 pounds, provides a maximum safe-delivery range of approximately 3,000 yards, the separation time in this instance being 16 seconds and the delivery time being about 33 seconds. Intermediate ranges are of course obtained by presetting the weapon for earlier separation times, and by way of example a range of approximately 2,100 yards for the described embodiment is obtained by imposing a separation time of 10 seconds.

It will now be understood that the described weapon is accelerated during the relatively short burning time of the rocket engine, and that the complete weapon proceeds along a ballistic trajectory until airframe separation takes place at a preselected and preset instant associated with the desired range, the payload thereafter continuing without the airframe to that range along a comparatively steeply descending path under deceleration and with limited terminal velocity as imposed by a drag parachute, the latter becoming uncoupled upon water-entry of the payload.

It will also be appreciated that while the detailed description of the invention has been given in terms of an embodiment specifically employing a conventional homing torpedo as the payload, other types of anti-submarine payloads may be used, e.g. of depth charge type having extremely high yield and adapted to detonate at a predetermined instant or at a predetermined depth, details of the particular payload however forming no part of the present invention.

Obviously many modifications and variations of the present invention are possible in the light of the above teachings. It is therefore to be understood that within the scope of the appended claims the invention may be practiced otherwise than as specifically described.

What is claimed is:

2. A weapon as defined in claim 1, wherein said ordnance apparatus is a homing torpedo for underwater search, pursuit and attack against a target submarine.

3. A weapon as defined in claim 1, wherein said deceleration means comprises a packed parachute having its opening-lanyard anchored to said airframe for parachute deployment during airframe separation.

4. A weapon as defined in claim 3, wherein said parachute is secured to the ordnance apparatus by a releasable coupling adapted to jettison the parachute upon water-entry of said ordnance apparatus.

5. A weapon for use against a target submarine, said weapon comprising, in combination: an ordnance apparatus effective to operate against a submerged target submarine when delivered to a suspect target area; a Wingless airframe positioned rearwardly of said ordnance apparatus and having hinged airbrake members folded forwardly against and engaging said ordnance apparatus; reaction propulsion means secured to said airframe and operative to project said weapon from a launcher and into a ballistic trajectory directed toward said suspect water area; releasable means for holding said airbrake members in engagement with said ordnance apparatus until a preselected instant during airflight of the weapon; separation means, including a presettable timing device, for releasing said releasable means upon expiration of a predetermined interval measured from the launch instant, whereby to render said airbrake members effective, at said preselected instant, to release, separate and jettison said airframe from said ordnance apparatus; and deceleration means secured by a releasable coupling apparatus to said ordnance device and becoming effective, upon separation and jettisoning of said airframe, to decelerate said ordnance apparatus to a safe water-entry speed, said coupling device being operative to jettison said deceleration means upon water-entry of said ordnance apparatus.

6. A weapon as defined in claim 5, wherein said ordnance apparatus is a homing torpedo operative to execute search, pursuit and attack against a target submarine.

7. A weapon as defined in claim 5, wherein said deceleration means comprises a packed parachute and a parachute-opening lanyard extending therefrom, said lanyard being anchored to said airframe to effect parachute extraction and deployment at substantially said preselected instant.

8. A weapon as defined in claim 5, wherein said releasable means includes a banding structure encircling and clamping said hinged airbrake members against said ordnance apparatus, said separation means including an explosive device positioned to sever said encircling band structure upon detonation of said explosive device, and means operated by said timing device at said preselected instant to detonate said explosive device.

9. A weapon for use against a target submarine, said weapon comprising, in combination: an ordnance apparatus effective to operate against a submerged target submarine when delivered to a suspect water area; a Wingless airframe severably secured to said ordnance apparatus, said airframe including reaction propulsion means to project said weapon from a launcher and into a ballistic trajectory directed toward said suspect water area; separation means including a presettable timing device for severing the airframe from said ordnance apparatus at a preselected instant during airflight; said airframe comprising hinged airbrake members folded into engagement with said ordnance apparatus and so maintained by banding until ruptured by said separation means; deceleration means secured to said ordnance apparatus and becoming effective upon separation of the airframe; and means for jettisoning said deceleration means upon water entry of said ordnance apparatus.