Title:
Bomb
United States Patent 2468140


Abstract:
The invention described herein may be manufactured and used by or -for the Government for governmental purposes without the payment to me of any royalty thereon. The invention relates to ammunition and means for projecting or dropping bombs and the like and has for an object to effect improvements...



Inventors:
Thornton, Lawrence W.
Application Number:
US54516644A
Publication Date:
04/26/1949
Filing Date:
07/15/1944
Assignee:
Thornton, Lawrence W.
Primary Class:
International Classes:
F42B12/20
View Patent Images:
US Patent References:
2354882Incendiary bomb1944-08-01
2330636Aerial bomb1943-09-28
2149254Constructional figure1939-03-07
1765017Drill projectile for bombarding planes1930-06-17
1741195Automatic bomb-dropping device1929-12-31
1632414Bomb dropper for aeroplanes1927-06-14
1623893Device for dropping bombs from aircraft1927-04-05
1546842Shell for infantry use1925-07-21
1359009Aerial bomb1920-11-16
1298222N/A1919-03-25
1272461N/A1918-07-16
0415719N/A1889-11-26



Foreign References:
FR494205A1919-09-03
GB419563A1934-11-14
Description:

The invention described herein may be manufactured and used by or -for the Government for governmental purposes without the payment to me of any royalty thereon.

The invention relates to ammunition and means for projecting or dropping bombs and the like and has for an object to effect improvements in projectiles of this nature, and particularly to .effect economy in materials and manufacture thereof, as well as to perfect details adding to efficiency of the projectiles against personnel .and to enable improvement of tactical practices.

A special aim of the invention is to effect an economy in ,shipping space for projectiles of a given weight of effective material.

Another end in view is to present a novel structure in a knock-down shell body and tail fin permitting shipment of the fins in flat sheet metal form stacked and adapted to be quickly attached without the use of machines by unskilled persons.

It is an important attainment of the invention that it is made possible to throw projectiles of somewhat fragile body structure which-containing high explosive and detonating means would be fractured by ordinary firing apparatus, thus enabling use of very light and cheap materials not ordinarily available for projectiles.

A further aim is to present a novel projectile nose and a novel point detonator construction for such projectiles.

As is well known, the angle of impact of bombs dropped from airplanes is proportional to the height of flight and inversely proportional to the speed of the plane, so that ordinary bombs with tail fins have an angle of impact of in the neighborhood of 70 degrees, even when dropped from a height of 5,000 feet. My invention conplates the dropping of a multiplicity of small projectiles from very low heights, as, for instance, one or two hundred feet, instead of "strafing" at similar heights with machine gunfire. At such levels and at the high speeds necessary both for maintaining effective flight as well as for relative safety from enemy fire, the angle of impact of the missiles will be extremely low, the elements of horizontal movement largely predominating over the vertical components, of this movement.

For this use, as well as for other uses it is a highly important purpose of my invention to present a point-located detonating device which will be highly effective under such conditions of flight of the projectile, and for response to impact on relatively soft materials, such as earth, sod, etc.

A still further important purpose of the invention is to present novel features of shell structure for anti-personnel, for dummy use, and for other special uses.

It is also a purpose to present novel structure in a catapulting device suited to the discharge of the projectiles as indicated.

In relation to economy of manufacture, a primary aim is, of course, to reduce the cost per unit of area of terrain in effecting adequate dispersion and also concentration of destructive elements, either fragmentative or concussive, but it is further an aim to at the same time effect a more uniform distribution of .highly effective concussion, or high velocity fragmentation with :a large number of fragments .per unit of area, than is accomplished by a corresponding use of projectiles currently available.

That is to say, using as a comparison present material and methods capable of distributing either a given quantity of explosive by weight, per unit of area, or projectiles of a given 'cost per unit of area, my method will reduce the changes of escape of enemy material and personnel within such area to a marked extent. In the ýcase of a given quantity of explosive applied t to a unit area, my invention effects improvemeht by a distinct manner of distribution by unit projectiles when exploded, by utilizing a novel structure whereby voids between fragments in the area are materially reduced, and by minia mizing the percentage of ineffective fragments too densely concentrated directly beneath the projectile when detonated and also by a constricbtion which increases the number of fragnientA and the certainty of uniform fragmentation. In addition, both as to material, and cost, I an enabled to produce a larger number of centers bf detonation so that spots between zones of effective concussion or dispersion of individual burst's are fewer, and greater casualties and demolitioi of material are effected.

Additional objects, advantages and features of invention reside in the construction, arrangeniaeit and combination of parts involved in the embodit ment of the invention, as will be apparent frotd the following description and accompanying drawings, wherein: Fig. 1 is a longitudinal sectional view of a shell embodying my invention; Fig. 2 is a cross section on the line 2-2 of Fig. 1; Fig. 3 is a section on the line 3-3 of Fig. 1; Fig. 4 is a view similar to Fig. 1 of a dumfmy shell, but showing the same safety device; Fig. 5 is a section on the line 5-5 of Fig. 4; Fig. 6 is a view similar to Fig. 1 of a modification; Fig. 7 is a section on the line 7-7 of Fig. 6; Fig. 8 is a plan of the blank for the tail fin; Fig. 9 is a fragmentary section of the wall joint or seam of the tail fin; Fig. 10 is a similar view of a modification of the joint or seam; Fig. 11 is a vertical section of a magazine and catapult device; Fig. 12 is a horizontal section of the catapult device; Fig. 13 is a cross section of the magazine and catapult; There is illustrated in Fig. 1 a shell, case, or body 20 consisting of a cylindrical wall 21 and integral slightly bulged back wall or head 22, the mouth or forward end of the shell opening flush with full diameter, being externally threaded and receiving thereon the interiorly threaded flange 23 of a thickened heavy cast iron nose cap 24 of a somewhat flattened ogival form, the head resistance of this projectile being a minor factor in contemplated uses, although in others it may conform to conventional shapes. The cap 24 has a flat inner face 25 in a plane normal to the axis of the body 20 while its outer or forward face 26 extends forwardly thereof a distance of less than one third the maximum diameter of the body 20. This cap is solid between these surfaces so as to afford a substantial mass at the nose, throwing the center of gravity of the body and content well forward of its middle. Clamped by the cap against the extremity of the case there is a planiform plate 27 centrally in which there is set a detonator cup 28 carrying a usual primer and booster, the details of which are well understood in analogous detonators for bursting charges and therefore not illustrated in detail here. Within the case 20 a bursting charge 29 of appropriate explosive is contained. A high explosive such as TNT may be employed, espe- , cially if a concussive effect is desired in addition to fragmentation functions. Various others are also available, suited to appropriate effects.

The shell body 20 is formed with a multiplicity of external conical studs 30 arranged in close 4 orderly relation throughout the areas of the wall 21 and head 22. These are arranged preferably in linear parallel rows extending from top to bottom of the body 21, the studs in each row being in line horizontally (circumferentially) with those in the next adjacent longitudinal row. The longitudinal rows are preferably inclined so that the longitudinal rows are actually spiral, the inclination being such as to include an angle of rotation around the shell axis at least equal to 5 that angle subtended by the spacing of the longitudinal rows, so that no two studs in the same row are located on the same radius of the shell axis, and also so that there will be comparatively few radii on which studs are not located.

For anti-personnel use as herein described, the studs may be circular and conical approximately one quarter inch in diameter at their bases and slightly spaced from each other to facilitate fragmentation of the wall and head, and the 65 studs may be about one quarter inch high from their bases to their apexes. The body portion of the wall 21 between its inner face and the bases of the studs may measure less than one quarter inch. The maximum diameter of the 7C shell may approximate that of a 60 mm. mortar shell and the length may be proportionate to the amount of explosive used, or the proportions and size varied in accordance with other factors.

Preferably, the complete projectile should weigh 75 less than two pounds for the specific use detailed herein.

The head cap 24 is flattened at its apex and axially bored entirely therethrough to receive r slidably and frictionally a longitudinally split firing pin 31, having a large mushroom-shaped head 32 of a diameter nearly or quite equal to the diameter of the shell body, and conforming to the shape of the external surface 26 of the nose cap 24 at the under side. This head is suitably spaced from the cap, its outer or forward side being slightly more conical, but of very low altitude, nevertheless. Its radial surface elements preferably extend at a mean angle of more than 45 degrees to the axis of the shell, for reasons which will appear. The pin 31 is formed with a furcated inner end, shaped so as to bind against the sides of the bore through the cap 24, and so that its extremities are pressed together; Sand it is suitably pointed to detonate the primer 28 when the pin is driven inward. Two parallel openings 33 are formed through the head 32 at each side, the pair at one side alined with those at the other side, and all being in a plane normal to the axis of the firing pin. Engaged through the openings are two parallel tines of a U-shaped wire safety pin 34 having an enlarged bight head 35. One of the tines has an outer part 36 inset slightly so as to engage the side of Sthe pin 31 and prevent withdrawal of the safety pin 34 except purposely. The pin 34 is so positioned that with the point of the pin 31 safely spaced from the detonator the pin 34 is immediately next to the flat outer face of the cap 24, and Swill stop inward movement of the firing pin until the safety pin 34 is withdrawn.

The body of the projectile is provided with a tail piece 37, formed as a single blank of sheet metal substantially as shown in Fig. 8, which I! may be assembled on the shell at a supply base.

The tail piece blank is preferably shipped from production plants in flat stacked form and manually or otherwise assembled on the shell body before distribution to the planes from which it is 5 to be fired. The tail blank may be given an initial set by which it tends to spring into cylindrical form when released from the bundled stacks in which it is kept flat. It is an oblong rectangular piece of sheet metal which may be ) of very thin stock, as, for instance, 26 guage elastic steel sheet or thinner material; having two narrow longitudinal annealed tongues 38 extending from one end edge while at the other end two short transverse slots 39 are formed in 5 the sheet parallel to the end edge and spaced from the latter about one-half the length of the tongues.

The length of the blank is equal to the circumference of the shell body 20 at the bases of 0 the studs, and along one longitudinal edge portion, and in close parallel relation to that edge, there is a series of apertures 40 each of a diameter equal to the base diameter of the studs 30, and similarly spaced so that these openings may Sbe engaged over the last series of the studs 30 on the wall 21 next the junction of the latter with the head 22, with the two end edges of the blank meeting flush, although an exact fit is not essential. The bases of the tongues 38 may be Soffset slightly to permit flush edge-to-edge meeting of the opposite sides of the blank. Each tongue is inserted through the respective alined slot 39 and bent inward towards its base, thereby holding the tail assembled.

Other means may be employed if desired to : -i :: hold the tail edges- connected; as forý instance a stapling machine of conventional: form now commercially available, by which a staple 4,1 may be coengaged across the meeting edges of a simple blank 31, as in Fig. 10.

The tail piece has cut and pressed inward therein. a pluarality of longitudinal fingers or vanes 43 formed by U-shaped slits or cuts 42 inw the blank transversely of the blank, the rounded bight portions of the cuts: being toward the edge of the blank having the apertures 40 therein. The extremities of the fingers thus formed are pressed inward a short distance so that each vane extends as a. planiform plate from its base at a very acute angle, to longitudinal elements of the tail, piece, and ports 44. being thus formed, adjacent, the forward part of the tail for functions which will be subsequently described.

In Fig. 4 there; is shown a modification of the shellibody in which a two-ply wall 45 constituting both body and tail is; shown, formed of plastic pulp; board, paper, or other fiber sheet stock, or other material, formed into. tubing by conventional methods. The wall; may consist of two complete tubes fitted telescopically and secured together by adhesives. This wall structure has the same length, and diameter as the combined shell body and tail: before described. At its rear or upper end vanes 43' are formed:of substantially the same size. and- shape as those designated 413. The nose, of this device consists, of a planiform closure plate 46 having a cylindrical flange 41 secured conventionally to andi around the end portion; of the wall .5,. and having set centrally therein a detonator 48: similar to the one 28 or otherwise constituted for detonating the bursting charge 49; which may bei a high explosive.

Over this a wad 50 is disposed.

Over the wad 50 a quantity of: dust-producing, or weight-imparting, or otherwise functioning material 51 is disposed, sand being indicated, in this instance. This sand is retained by a disc 52 consisting in this instance of a double thickness of strong fiber plate- or other sheet material.

The disc is shown as secured to the wall by means of an L angle collar 53 riveted or otherwise secured to the wall in tight engagement with the disc.

The nose of this projectile is completed by a dome-like pressed sheet metal nose piece 54 having a cylindrical base portion or flange 55 fitted snugly over and riveted to the flange 47 and underlying portion of the wall 45. A planiform circular plate 56 it secured at its peripheral edge to the nose piece 54 near its base. The apex of the nose piece is flattened in a plane normal to the axis of the projectile, and-both this flat and the plate 56 are axially punched and'formed with annular guide sleeves as at 571 through which the firing pin 31 is engaged' slidably and frictionally as in the cap 24. All details of' the firing pin. and: its head, as well- as the safety pin 34 are the same as before described.

The wall 45- has secured exteriorly thereon three, longitudinally spaced metal collars 58, Lshaped in section, one flange secured against the wall and the other projecting at right angles in a:plane normal to the projectile axis; These may reinforce the wall of the projectile body, but are especially intended, to serve as; holds or thrust ribs to be engaged by fingers of a propelling device or catapult to be described; The shell last described; has a. use coordinated with the use of the first; described' projectile which, will be., understood; by: tacticians, and the form shownI in, Fig. 6 now to be described has possibilities of related use in conjunction with the first two described,, as wilt be explained.

In Fig. 6, the projectile body consists of a silpie cylindrical thin, relatively soft metal-walled barrel or tube 59 of the same diameter andlength as the body and tail part in each of the first two. forms: of projectile- described herein. Three integral planiform circumferential ribs 60 are formed thereon,, spaced longitudinally to correspond to the positions of the collars 58; and intended for the same uses. The wall portion above the uppermost rib 60 constitutes, the tail: 611 and is formed with inwardly pressed vanes 43, the same as. in. the tail 371 of Fig. 1. A liquid-tight head 62 is fixed across the barrel at or adjacent the upper rib 60W The barrel extends a distance below the lowermost rib 60 and is formed with pressed' threads 63 extending to its extremity. This end of the barrel, is closed by an introverted conical head 64, forming a chamber 65 inwardly thereof and' a cavity in the end of the barrel.

Within this cavity a, bursting charge 66 is confined by means off a planiform outer head plate 67 having a screw flange, 69 screwed onto the threads of the barrel end. Within the chamber 65 an inflammable liquid 656 is confined. The plate 67; has a primer-detonator 68 set therein, which may be the same as thoseý 28 and 48.

An outer heavy cast iron cap 0: similar to the one 24; except that coarser threads. are formed thereon is screwed on to the end of the barrel, and has the firing pin' 31 engaged therethrough the same as before described, and' having the same safety pin 34. The wall-of the- barrel between the ribs. 60 is scored as at 71 in. a suitable manner to weaken it slightly along certain lines so that on, detonation of the charge 66. the material will, split under thet hydrostatic pressure, inducing the projection of masses of- the liquid to considerable distances; rattherthan spraying the liquidifinely.

It is planned to use the projectiles of Fig. 1 very largely as an anti-personnel weapon, and the others for special purposes which are well understood. In addition, projectiles of the same size and shape may be produced in accordance with practices known for producing smoke, fog vapors or other gases or effects.

All are intended principally to be dropped or discharged from airplanes, and for this purpose I have disclosed: means for effecting this mechanically and automatically. On account of the mass of the projectiles: and their relatively frail structure, as well as to avoid complication in machine details and to minimize weight in 'the apparatus, I.have preferred to embody the machine so as- to discharge the shells at a very moderate speed, say, one per second; and where tree top strafing requires the dropping of several each second along a given line, I am able to connect my discharge machines in gangs mutually connedted to operate successively in rapid succession to each other without requiring abrupt or rapid movement of any projectile, or operating mechanism.

The device illustrated comprises a magazine 5: constructed to hold a quantity of the projectiles, formally represented in Figs. 11' to 13 inclusive, and to deliver them in ordered arrangement through a loading device to the catapult.

In this instance the base structure 16 of the catapult includes a trough-like tray 77 which extends from under the- magazine in the desired direction' of. discharge to, a proper distance; as, to a port in the fuselage or other body structure of an airplane. It is contemplated that one or more may be mounted in each wing and also on the longitudinal medial vertical plane of the craft.

Or, instead of in the wings, the lateral devices may a be arranged to discharge shells at opposite sides of the fuselage so that they will reach the ground at a desired distance from a ground course of the craft.

The magazine includes a lower chute 78 the 1 interior cross sectional dimensions of which correspond to the longitudinal and diametrical dimensions of the projectile to be accommodated, and the chute is vertically alined with a receiving port of the shuttle 80 as in Figs. 11 and 131 ]1 The chute terminates a distance above the tray 77 slightly more than twice the diameter of the projectile.

In a suitable horizontal guide framing 79 immediately under the chute a projectile feeding ^ valve or shuttle 80 is reciprocable consisting of a box-like member twice the length of the projectile, reciprocable from a rear position as in Fig. 11 with its forward half under the chute to a forward position with its rear half under the 2V chute. The forward half of the shuttle includes a top plate 8 Iclose under the mouth of the chute and closing the same in its rear position while the rear part of the shuttle is open at the upper side, with a port 82, so as to form a continuation 3C of the chute when the shuttle is in forward position. The bottom of the shuttle is closed at its rear part by a bottom plate 83 of the same extent as the plate 81 while the forward end of the bottom is open with a port clearance the .5 same as that in the chute 78. The shuttle in. cludes vertical side walls 84 extending throughout its length. It may include also a front wall 85 closing its forward end. It is supported conventionally for its sliding movement. The walls 84 are longitudinally slotted midway of their height, these slots 86 being coextensive with the bottom plate of the shuttle, and a stationary cross bar 87 is fixed on ,the framing 79 extending horizontally across the shuttle through the slots as a support for the shuttle and stop for rounds dropped from the magazine, this bar being positioned under the rear side of the mouth of the chute 78. The shuttle has pivot ears 88 projected rearwardly therefrom between which there is pivoted a pitman 89, the opposite end of which is connected to the wrist 105 of a crank shaft 90 with a throw equal the extent of movement required in the shuttle, the shaft being shown as horizontal. In the lower part of the framing there is a pair of horizontal guide channels 91 located adjacent the level of the longitudinal axis of a projectile laid in 'the tray 77, and reciprocable in these there is a catapult carriage 92 consisting of parallel side bars 93 in respective channels, connected at their rear ends by a cross member 94 having rigidly fixed thereon a rearwardly extended plunger 95 carrying a lateral wiper wheel 96 arranged to rotate in a vertical plane to one side of the plunger and beyond the plane of movement of the crank of the shaft 90.

On the shaft 90 beside the crank there is a cam 97 consisting of a planiform plate having a cam flange 98 projected laterally therefrom at the side next the wiper 96. This cam may be considerably varied in form but in the present instance has a form correlated as will be later explained, to the function of the carriage and certain grippers thereon now to be described, Pivoted on each of the side bars 93 there arq pivoted pusher dogs 99 having gripper jaws 100 which in normal position project over the tray 77 sufficiently to engage behind respective collars 58 or ribs 60 of projectiles or to engage between rows of studs 30 of the first described projectile, as the case may be. The dogs are free to move forwardly on their pivots to clear the projectiles, but are checked in rearward move0 ment when fully extended, by suitable means, pins 101 being shown set in the bars 93 to receive the jaws thereagainst under rearward movement.

Leaf springs 102 are mounted on the bars 93 bearing the jaws rearwardly against the pins, Sbut yieldable to pressure of ribs or collars of projectiles when the projectile moves forwardly with the tips of the jaws striking the collars or ribs, or the tips of the studs 30. The jaws 100 may be broadened if desired to insure their engageSment with two or more of the studs 30 if desired.

The dogs on each bar are spaced longitudinally the same as the collars and ribs of the projectiles and respective circumferential rows of studs 30 also fall at the same intervals, so that any of the three forms of projectiles may be used alternatively in the catapult, as well as other projectiles having similarly spaced lateral projections.

The framing includes a back plate 103 through which the plunger 95 extends slidably, the wiper Sbeing spaced rearwardly of this plate when the carriage 92 is at the forward limit of its movement.

The helical compression spring 104 is confined between the cross member 94 of the carriage and the back plate 103 of the framing, the cross member having movement with the carriage longitudinally somewhat less than the length of one of the projectiles although the proportions may be varied in this respect as found desirable Sand expedient.

The cam flange has ends of maximum and minimum radius adjacent diametrically opposite radii of the shaft and the wrist 105 of the crank of the shaft may be close to or on the same radius as the cam end of maximum radius. The flange is curved progressively between its extremities.

The mounting of the wiper 96 may include a head block 106 positioned on the plunger to engage the back plate 103 when the carriage is at its forward limit of movement, the wiper being then spaced from the back plate. The shaft rotates in the direction in which the part of the cam of maximum radius is advanced as indicated by the arrow in Fig. 11, and with the wiper in released position, it is sufficiently within the maximum radius of the cam to permit entry of the advancing end of the cam between the wiper and back plate 103. Continued rotation of the cam then draws the wiper and carriage rearwardly, at the same time that the crank and wrist 105 draw the shuttle rearwardly. The inner face of the cam flange thus serves as the cam surface.

Near the end of minimum radius, the flange 98 is formed with a slight rise or lobe 107 comprising a thickening of the flange at the inner side only and involving an abrupt reduction of radius of the cam surface, the flange continuing at 108 a short distance beyond this lobe to its trailing extremity 109 as a symmetrical continuation of the curved part of the cam inward of the lobe-that is, with somewhat increased radius. As a result, when the trailing end portion of the cam engages the wiper the carriage is drawn rearwardly and then allowed to move forwardly a short distance before the wiper clears the cam.

The position of the carriage when the wiper is at the apex of the lobe 107 is such that the jaws 100 are rearwardly of position for engagement with the collars or corresponding parts of projectiles, but as the wiper engages the extreme part of the cam, the carriage is permitted to move forwardly sufficiently for the jaws to engage properly if a projectile is in place. 1 The pitman 89 is connected to the shuttle 80 at a higher level than that of the plunger, and in order to prevent interference with the plunger may be connected with the shuttle at one side of the vertical plane of the plunger. 1 The crank of the shaft is likewise spaced from the cam so that it may swing clear of the plunger.

Before loading the magazine 15, the safety pins 34 are extracted.

In the use of the apparatus, the shaft 90 may be 2 manually or power driven, and when set in motion, operation of the crank and pitman will reciprocate the shuttle as a loader for the catapult, while rotation of the cam will cause operation of the catapult immediately after each round 2 is loaded by the shuttle.

With the shuttle in position as in Fig. 11, its next movement will be forward, allowing the first projectile in the chute to drop through the port 82 to rest on the bottom plate 83. The rear edge 3 of the top plate 81 is bevelled on its upper side, and the projectile next above the one newly received in the shuttle will have an inclined part of its cap 24 in line with this bevelled edge. At about the time that the shuttle starts its forward movement the wiper 96 will clear the trailing end of the cam flange and the compressed spring will expand, propelling the carriage 92 forwardly and throwing the preceding projectile along the tray 77 with sufficient velocity to carry it to a proper distance, according to the strength of the spring.

Expedients for varying the degree of compression of the spring under the same movements of the carriage may be used if desired, to vary the range attained.

On return rearward movement of the shuttle from its position last named, the projectile resting on the bottom plate 83 will be held against rearward movement by the cross bar 87, while the rear edge of the top plate will cam the lowermost projectile in the chute upward and pass rearwardly thereunder, the bevelled edge of the plate engaging below the collars or ribs and lifting the projectiles in the chute.

As the bottom plate 83 passes from under the projectile last received, in the shuttle, this projectile will drop to the now empty tray; first the forward end of the projectile fa!ling, and finally the rear end. At about the time the shuttle starts its rearward motion, the advancing end of the cam will be engaging in .front of the wiper, and the rearward camming of the carriage will be effected as the shuttle moves rearward, the spring 94 being thereby compressed.

The wiper will be at the apex of the lobe 107 of the cam about when the rear end of the projectile drops to the tray. The jaws 100 will then be located just to the rear of the collars, studs, or ribs of the projectile. As the lobe 107 passes the wiper, the carriage is thereby permitted to move slowly forward so that the jaws 100 engage the collars or ribs of the projectile, or the studs 30, as the case may be. Thereafter, the wiper clears the trailing end of the cam, permitting the catapult action to be repeated.

Upon discharge of a projectile at low altitude it will describe a trajectory in accordance with its velocity and mass, speed of the plane, air resistance and other factors, reaching the ground or object while still moving at a substantial speed due to remaining inertia of momentum imparted by movement of the plane, as well as with elements of motion due to operation of the catapult device. By directing the catapults 0 toward the rear of the plane, much, if not all, of the movement of the plane may be negative in the trajectory so as to increase the angle of impact, but, even without such or other correction for the same purpose, due to the construction of my firing pin the projectile is effective at very small angles of impact, and on moderately yielding materials, such as sod, plowed soil, hay stacks, etc.

On account of the periphery of the head 32 0 being very close to the sides of the projectile, the likelihood of ricochet before detonation is reduced materially.

The angle of the axis of the projectile to the horizontal is considerably increased by the ,3 weighting of the nose caps 24.

In the event that a number of the catapults are used to project the bombs in one general direction, a common operating shaft 90 may be used for all, with the cams and cranks for reio spective catapults arranged on different radii of the shaft, so that the several devices connected with the shaft will be operated in succession at proper intervals. In this way several projectiles may be fired within a second of time, although 35 each catapult may operate at one second intervals. This minimizes liability of accident by too abrupt movement and stoppage of projectiles in the loader, as well as relieving the mechanism of severe stresses, and avoiding likelihood of frac40 ture of frail projectile structure.

In the flight of the projectile any movement thereof with its axis at a material angle to the trajectory will be quickly corrected by reason of the extreme forward position of the center of 45 gravity with relation to the lateral air pressures, and in this respect the construction proportions and tail form may be found of value more generally for bombs.

With the projectile axis alined with or ap5o proximating more closely the line of the trajectory, the ports 44 serve to lessen retardation by reducing without abruptness the vacuous condition developed behind the projectile and also oppose rotation of the projectile.

The conical head 64 is preferably of weaker material than the external walls of the barrel 59 and may be weakened specially at its inner part if a low pressure explosive is used. Preferably the bursting charge 66 is a relatively slow burnSing one, so as to effect cleavage of the wall without fragmentation or scattering of pieces of the wall, but so that a moderate pressure will be maintained after sufficient opening of the wall of the barrel to form jets of liquid, or to project ,. moderately large masses of the liquid.

In one construction of the tail, the securing means at the longitudinal seam may be perfected while the tail is separate from the body, leaving the seam open for a distance from the end, after 70 which the tail may be put in place by simply thrusting it longitudinally on to the body until the lugs 30 snap-engage the apertures 40.

While I have disclosed my invention with particularity in its best form known to me, it will 75 nevertheless be understood that this is purely exemplary and that modification in the structure arrangement and combination of parts, and substitution of materials and equivalents, mechanical and otherwise, may be made without departing from the spirit of the invention as set forth in the appended claims.

As a part of the tactical coordination of the explosives shown, it is significant that the several projectiles of widely differing functions and explosive effects, differing in weights if necessary, and using a wide range of materials, some of them too frail for mortar firing may all be fired from the same apparatus, with good effect.

The three projectiles of Figs. 1, 4 and 6 are designed for cooperative military use, and while projectiles of differing functions have heretofore been use in coordination, as, demolition, incendiary and fragmentation devices, there is a peculiar coordination in the present instance that would leave, say, the device of Fig. 4 without peculiar utility if used alone and in which the device of Fig. 6 would be otherwise constructed if mere incendiary functions were required.

Thus, it is contemplated to carry out an aerial attack to a stage of effectiveness using the projectile of Fig. 1, and also using projectiles as in Fig. 6 conjointly and especially in the latter part of the attack with the Fig. 1 projectile, then discontinuing the use of the Fig. 1 projectile and the one of Fig. 6, and concurrently, and with sustained fire and continuity of average interval, as to times or number of explosive units, and as to distribution, beginning the use of the projectiles of Fig. 4, ceasing the use of the first two projectiles or any actually or comparatively destructive projectiles. The projectiles of Fig. 4 will throw no fragments of dangerous nature and will produce only loud explosions accompanied by the appearance of destructive effect, but actually only throwing the sand contents 51 harmlessly, possibly accompanied by a small amount of dirt or rubble in which the projectile may have fallen, and which will be thrown only a few feet with small force.

An infantry force will have been prepared as a part of the attack, and before discontinuance of the use of the Fig. 1 projectiles in this attack the infantry will be moved forward to the edge of the zone of effectiveness of the Fig. 1 projectiles.

The use of the latter projectiles will then, or immediately before, be discontinued; and the use solely of the Fig. 4 form continued while the infantry moves forward into the zone of effectiveness of the earlier dropped Fig. 1 projectiles.

The dropping of the Fig. 4 projectiles is discontinued at the line of infantry advance but moved forward over the enemy-occupied territory and beyond, so that the whole objective area becomes fully occupied by the attacking infantry while explosions simulating aerial attack are continued so near that it would be dangerous if the missiles were antipersonnel in nature.

In the infantry advance some of the last projectiles of Fig. 6 may still be functioning, or the fires caused thereby in buildings and other material will still be raging, so that activity of the enemy will be greatly limited and the infiltrating infantry carrying on the attack may select and take positions of vantage to subdue any survivors of the earlier destructive attack who may appear from places of cover or concealment.

I claim: 1. A projectile of the character described comprising a body having a plurality of stud-like members, and a substantially tubular tail member of thin sheet material having openings positioned to receive the stud-like members when the body and tail member are in flight relation.

2. The structure of claim 1 in which the last named means consists of peripheral studs on the body, said tail having corresponding openings at one end to engage over the studs.

3. A projectile body having peripheral studs and a tail piece comprising a blank of sheet metal adapted to be bent around the base of the projectile and having apertures to engage over the studs, and means to hold the tail in engaged form on the body.

4. A projectile of the character described comprising a shell including a wall having, at one part at least, a circumferential part, said wall being formed with a multiplicity of studs to define lines of fragmentation, a plurality of said studs being located on said circumferential part and spaced thereon, and a tail including a contractable embracing part to fit said circumferential part and apertured at intervals corresponding to the studs, 85 whereby to receive those at the circumferential part.

LAWRENCE W. THORNTON.

REFERENCES CITED The following references are of record in the file of this patent: UNITED STATES PATENTS Number 415,719 1,272,461 1,298,222 1,359,009 1,546,842 1,623,893 1,632,414 1,741,195 1,765,017 2,149,254 2,330,636 2,354,882 Number 494,205 419,563 Name Date Langfitt --------- Nov. 26, 1889 Kocialek ----------- July 16, 1918 Kane _------------- Mar. 25, 1919 Williams ---------- Nov. 16, 1920 Lafitte _----------_ July 21, 1925 Swiatecki----------- Apr. 5, 1927 Nosan ------------ June 14, 1927 Lombardo --------- Dec. 31, 1929 Marie ------------- June 17,1930 Corswirt ----------- Mar. 7, 1939 Smith ------------ Sept. 28, 1943 Samann ------------ Aug. 1, 1944 FOREIGN PATENTS Country Date France _________-- May 24, 1919 Great Britain ------- Nov. 14, 1934