US3282714A - Ballistically stabilized white phosphorus shell - Google Patents

Description

Nov. 1, 1966 R. l. WESSELLS 3,282,714

BALLISTICALLY STABILIZED WHITE PHOSPHORUS SHELL Filed Nov. 2. 1964 INVENTOR.

m w a W lw w., Rm 4 BY 6% l n; I W E Q/ 91 a G ATTORNEYS 3,282,714 BALLHSTTCALLY STABILIZED WHITE PHQSPHORUS SHELL Russell 1. Wessells, Baltimore, Md., assignor to the United tates of America as represented by the Secretary of the Army Filed Nov. 2, 1964, Ser. No. 403,444 3 Claims. (Cl. 102-66) 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 to me of any royalty thereon.

This invention relates to munitions, and more particularly to means for flight stabilizing white phosphorus filled projectiles or shells which disseminate the white phosphorus upon impact with a target.

The main object of the invention is the provision of a projectile burster casing that has formed about its outer surface a plurality of fins or impellers of which the main purpose is to ballistically stabilize a white phosphorus filled projectile.

A further object of this invention is to ballistically stabilize a white phosphorus filled projectile when the white phosphorus is in a liquid state. The principle involved is to force the liquid white phosphorus to obtain the same, or nearly the same spin rate or angular velocity as that of the projectile and to eliminate any forces that the liquid white phosphorus may set up within the projectile that would cause it to yaw or tumble in flight and fall short of the intended range. It is to be noted here that the name white phosphorus hereinafter will be referred to, or be called, by its other well known short designation WP. White phosphorus is also called yellow phosphorus.

The problem of projectile stabilization has existed for many years and has become more critical in the modern thin-wall projectiles, in which case the weight of the projectile is proportionately small compared to the weight of the WP filler. Projectiles filled with the WP must be ballistically stable over temperature range from 65 F. to 140 F. White phosphorus becomes a liquid at temperatures above 112.1 F. (445 C.) and has a density of 1.745.

Various methods were exploited in the past to remedy the existing deficiencies in projectile stabilization. For example, internal bafiies, or vanes and bellows have been fastened to the walls of projectiles in an elfort to flight stabilize the latter when WP Was in liquid state. None of the above mentioned methods that were tried proved to be successful. Moreover, the numerous devices that were tried, were difficult to insert or fasten within the projectile. Furthermore, the fastening of these devices to projectile walls interfered with the formation of a void space. A projectile or shell cannot be completely filled with WP, since a space or void must be provided for expansion when the projectile is heated. This void adds to the problem of flight stabilization.

For example, WP shells must be stored upright for best results because if they are left horizontal in the hot sun or stored under tropic conditions, the WP melts and when it hardens again the void will be somewhere on the side of the shell. When this shell is subsequently fired in a rifled cannon, the high revolutions per minute (approximately 25,000 r.p.m.) imparted to the projectile by the action of the rifling bands on the rifled bore, will cause the projectile to wobble or tumble in flight. This greatly reduces the expected range of the weapon and has caused casualties to friendly troops rather than enemy troops. My invention will not correct the problem of improper storage but it will tend to prevent the ballistic problem that arises when these shells are fired since the fins provided by my tates Patent 3,282,714 Patented Nov. 1, 1966 invention tend to act as a heat sink in the center of the molten WP. When this mass is cooling off, there is evidence to show that the void forms at or near the fins in the approximate center of gravity of the shell rather than at the extreme inside surface of the shell. Thus, my invention will stabilize liquid (or hot) WP shells and solid (or cold) WP shells that have been improperly stored.

Projectiles containing the finned type burster casings were tested and proven to be ballistically stable at all ranges and at the required temperatures of -6S F. to F. The fins or the impellers of the burster casing succeeded in acceleration of the liquid WP to the same or nearly the same rate as that of the projectile itself.

Other more important advantages of my invention are that the fins serve the purpose of preventing the free longitudinal movement or oscillation of the liquid WP, that the fins swirl the liquid WP in flight so that the void is reduced to a thin vortex on the axis of rotation of the shell, and that the fins force the WP to act substantially the same as a solid substance.

A still further advantage of my invention is that in mass production of ammunition it is desirable to have one basic shell which can be adapted to suit various requirements rather than have several specialized shells which must be supplied in limited production. My invention supplies this need since the empty shell can be supplied in lots of a million or more and be used as high explosive rounds or WP rounds without extensive and expensive modification of the basic shell.

Other objects and advantages of this invention will become apparent as the following description is read in connection with the accompanying drawing in which:

FIGURE 1 is a sectional view of a projectile showing the finned projectile burster casing.

FIGURE 2 is a cross sectional view taken at 22 showing a plurality of fins.

FIGURE 3 is a diagrammatic view of a shell combined with the shell casing.

Referring to the drawing, 10 designates the projectile or shell body which is provided with a pair of riding bands 11, a base plug 13 having a tracer (or dummy of equal weight) 15 and a burster casing 17 containing a rotationally armed impact fuze 19, booster charge 20, and burster charge 21 respectively. The fuze, booster, and the burster may be of any suitable conventional type as those for example which are shown and described in the US. patent to Weeke, No. 1,417,475. The bottom of the well portion of the burster casing 17 has extruded or fastened onto it a plurality of 3-12 (preferably 6) radial and longitudinally extending straight fins or impellers 23.

The projectile 10 is filled with molten white phosphorus 25 and the burster casing 17 is force-fitted within the latter thereby creating a leak-proof joint at 27. Thus, the WP is sealed within the projectile by means of the interference fit between the burster casing and the shell walls. The shell 10 is contained within a shell casing 29.

This invention also enables the present US. Army standard projectile casing to be easily modified to become a WP projectile or a high explosive (HE) projectile. The WP projectile therefore becomes interchangeable with the standard HE projectile when using my invention. This means that the HE projectile can be fired and be followed immediately with the firing of a WP projectile without any gun site corrections being made. It is highly desirable, if not mandatory, that these two types of ammunition be identical in weight and external shape and be a ballistic match over all flight zones. This has been accomplished by adding fins or impellers to the burster casing. This invention can be used in any caliber gun in which a modern thin walled shell is being used such as the 75, 105, 152 and mm. types. The problem which this invention solves is particularly acute in 105 mm. tank mounted guns Where the ammunition frequently is subjected to temperatures above the melting point of WP as for example under desert conditions.

It will, of course, be understood that various details of construction such as the number of fins 23 may be varied through a wide range Without departing from the principles of this invention and I therefore do not wish to be limited to the details shown and described.

I claim:

1. A phosphorus disseminating projectile comprising:

(1) a hollow ogive-shape-d body means having an opening in the base end;

(2) burster casing means mounted in sealing relationship With said opening and extending a predetermined axial distance interiorly of said body;

(a) said casing means having fuze means sealed therein adjacent to said opening;

(b) said casing means having a portion thereof containing explosive means remote from said opening and detonatably connected to said fuze;

(c) said casing means having a plurality of radially and longitudinally extending fin means being wholly supported by and integral with said explosive charge portion.

2. A phosphorus disseminating projectile comprising in combination:

(1) a hollow ogive-shaped body having an axial opening in the base end;

(2) a burster casing mounted in sealing relationship with said opening and extending a predetermined axial distance interiorly of said body;

(a) said casing having a fuze sealed therein adjacent to said opening;

(b) said casing having a portion thereof containing a burster charge remote from said opening and detonatably connected to said fuze;

(c) said casing having a plurality of radially and longitudinally extending fins being Wholly supported by and integral With said burster charge portion.

3. In a phosphorus disseminating projectile comprising a hollow, ogive-shaped body having an axially located, longitudinally extending burster casing with a fuze and burster charge therein sealing the base end of said body, the improvement which comprises providing said burster casing with a plurality of radially and longitudinally extending fins which are Wholly supported by and integral with said burster casing.

References Cited by the Examiner UNITED STATES PATENTS 1,311,521 7/1919 Johnson 102-66 1,819,106 8/1931 McBride et a1. 102-66 3,103,888 9/1963 Rosenthal 102-66 References (Iited by the Applicant UNITED STATES PATENTS 1,417,475 5/1922 Weeke. 1,878,491 9/1932 Goss. 2,774,305 12/ 1956 Fitzgerald et a1.

SAMUEL FEINB-ERG, Primary Examiner.

FRED C. MATTERN, JR., Examiner.

W. KUJAWA, Assistant Examiner.

Claims (1)

1. A PHOSPHORUS DISSEMINATING PROJECTILE COMPRISING: (1) A HOLLOW OGIVE-SHAPED BODY MEANS HAVING AN OPENING IN THE BASE END; (2) BURSTER CASING MEANS MOUNTED IN SEALING RELATIONSHIP WITH SAID OPENING AND EXTENDING A PREDETERMINED AXIAL DISTANCE INTERIORLY OF SAID BODY; (A) SAID CASING MEANS HAVING FUZE A PORTION THEREOF THEREIN ADJACENT TO SAID OPENING; (B) SAID CASING MEANS HAVING A PORTION THEREOF CONTAINING EXPLOSIVE MEANS REMOTE FROM SAID OPENING AND DETONATABLY CONNECTED TO SAID FUZE; (C) SAID CASING MEANS HAVING A PLURALITY OF RADIALLY AND LONGITUDINALLY EXTENDING FIN MEANS BEING WHOLLY SUPPORTED BY AND INTEGRAL WITH SAID EXPLOSIVE CHARGE PORTION.

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