US 3318241 A
Description (OCR text may contain errors)
1967 B. B. GOULD 3,318,241
DISPERSAL OF ROCKETS Original Filed June 21, 1961 Fly. 1
I INVENTOR. 1a
5527 5. 60040 Fl;- 5 BY ATTOZ/VEKS 3,318,241 DISPERSAL OF RUCKETS Bert B. Gould, Berkeley, Calif., assignor, by mesne assignments, to MB Associates, San Ramon, Calif. Continuation of application Ser. No. 118,685, June 21, 1961. This application Feb. 4, 1965, Ser. No. 431,778 4 Claims. (Cl. 102-7.2)
This invention relates to a method and apparatus for the aerial launching of a plurality of miniature rockets.
This application is a continuation of my copending application Ser. No. 118,685, filed June 21, 1961, now abandoned, and entitled, Dispersal of Rockets.
Aerial launching of large rockets is accomplished singly, with orientation and guidance supplied by the launching platform (aircraft or first stage rockets) or the target. The miniature rockets to which this invention relates are too small to include guidance mechanisms and, to be effective, are launched in such large numbers that individual launching platforms would be impracticable. Said miniature rockets are extremely small in size wherein the rocket has a diameter about 1.5 to 3 millimeters. Such miniature rockets, aerially launched in a downward direction, are an effective weapon against dispersed troops in foxholes or trenches. It is, of course, desirable that excessive concentrations of such miniature rockets be avoided directly below the launching point.
A suitable method for accomplishing these objectives has been devised, comprising three steps of dispersion, orientation and ignition. Dispersion is effected by the use of a slow explosive, by air blast, or by centrifugal force. A timed period of free fall will orient rockets of proper design. Ignition effected by the ambient atmosphere ends the free fall and starts powered flight to the target.
In the drawings forming part of this application:
FIGURE 1 is a side view of a warhead of a shell or rocket opening to permit dispersion;
FIGURE 2 is a section through the warhead after the protective insulation has been removed;
FIGURE 3 is an enlarged diagram of the essential elements in the orientation of a miniature rocket;
FIGURE 4 is an elevation view of the paths of free fall and powered flights; and
FIGURE 5 is an enlarged section view of a miniature rocket showing the method of ignition.
Turning now to a description of the drawings by reference characters, there is shown the body of a projectile 1, either shell or rocket, at the instant of separation of segments 2, of forward insulating skin. An explosive charge 3 is used to accomplish separation. A series of trays 4, inside the warhead, hold miniature rockets 6.
If the projectile 1 is rotating on its axis when the charge 3 is exploded, centrifugal force will disperse the miniature rockets 6 to all sides. Alternatively, or in addition thereto a second charge may be exploded in the central cavity 5 to propel the trays 4 and thereby the miniature rockets 6 to all sides. Also, a conical forward entrance 7 to the cavity 5 may be employed to propel the trays 4 to all sides by air pressure generated from the downward motion of the projectile. The trays may be connected to each other by lengths of cable (not shown) to insure movement of the miniature rockets free of the trays 4 after lateral acceleration.
Once a miniature rocket 6, as shown in FIGURE 3, is in free flight, the inertial force resulting from its lateral velocity and the similar force from the original downward velocity of the projectile 1, plus gravity, will act on the center of gravity 8A of the rocket as shown by the arrow. Air drag will act on the center of pressure 8B of the rocket as shown by the arrow attached to that point. Because the center of gravity 8A is forward of the center pressure 8B, the rocket will rotate as shown by the curved arrows nited States Patent ice until it is oriented in the direction of its motion through the air. To aid in the separation of the centers of gravity and pressure, fins may be added to move the center of pressure rearward, or the nose of the rocket may be weighted to move the center of gravity forward.
From the point of aerial dispersion 9, FIGURE 4 shows the theoretical trajectories 10, 11, 12 of miniature rockets expelled laterally with high, intermediate and low velocity respectively. After the ignition point 13 these trajectories are powered and substantially straight. However, such trajectories are not desirable in that the pattern at ground level 15 will not cover an area directly below the point of dispersion 9, and since most of the miniature rockets will receive substantially identical lateral accelerations, said trajectories will tend to concentrate in a ring at ground level. On the opposite side of the centerline of FIGURE 4 are shown more realistic trajectories 14, in which allowance has been made for random variations in orientation and time of free fall before ignition. Such variations effect even coverage of the ground level 15. It is therefore important to avoid excessive orientation moments (FIGURE 3) that will bring all rockets to complete alignment with their theoretical trajectories before powered flight. Variations in the time of free fall act to select a different slope on the descending parabola and add to the randomness of the distribution.
In FIGURE 5, the enlarged section of a miniature rocket 6, shows the method by which ignition may be accomplished. The fuse 16 extends through the nozzle 17 and the central port of the propellant grain 18. A small piece of white phosphorus 19 is fastened into the nozzle exit in contact with the fuse 16 with a combustible cement 20 such as nitrocellulose. An inert, non-oxidizing atmosphere such as nitrogen, argon, or carbon dioxide is maintained around the rocket. Handling of the miniature rockets is thereafter accomplished in a similar non-oxidizing atmosphere, including delivery over the target in the warhead of a projectile. When the insulating skin is removed as shown in FIGURE 1, air reaches the pellet of white phosphorus and causes ignition of the fuse. Since ignition of the propellant will not occur until the fuse has burned substantially through the propellant, the time of free fall may be altered by adjusting the burning speed of the fuse.
1. The method of dispersal firing of clusters of miniature rockets towards a target area comprising the steps of releasing a bomblet containing a multiplicity of miniature tubular rockets containing propellant for self-propulsion and having a center of gravity and a center of pressure with the center of gravity between the center of pressure and the forward end of the rocket and the center of pressure between the center of gravity and the aft end of the rocket, opening the bomblet while in flight above the surface of the earth, allowing the rockets to fall in free flight free of the bomblet whereby the centers of gravity and the centers of pressure react to the surrounding atmosphere substantially to align the rockets with the direction of flight and to effect dispersal of the rockets, and igniting the propellant while in the directed flight whereby the rockets become self-propelled towards the target area.
2. The method of dispersal firing of clusters of miniature rockets comprising the steps of releasing a bomblet containing a multiplicity of miniature tubular rockets containing propellant for self-propulsion and having their center of gravity and center of pressure arranged with the center of gravity between the center of pressure and the forward end of the rocket and the center of pressure between the center of gravity and the aft end of the rocket, opening the bomblet in flight above the surface of the earth to release the multiplicity of rockets, allowing the rockets to fall in free flight for a distance short of the surface of the earth whereby the centers of gravity and the centers of pressure operate to align the rockets with the direction of flight and to effect dispersal of the rockets, causing the propellant to ignite during directed free flight whereby the rockets are propelled in the direction of flight to the earth.
3. The method as claimed in claim 2 which includes the step of firing an explosive within the bomblet for opening the bomblet and dispersing the rockets originally housed therein.
4. A warhead for a projectile or rocket comprising in combination:
(a) a protective covering enclosing a holding structure;
(b) a plurality of miniature rockets within said cover- (c) said covering being hermetically sealed and having an inert gas filling;
(d) Said plurality of miniature rockets within said cover being held by said holding structure;
(e) each of said rockets having a fuse therein which References Cited by the Examiner UNITED STATES PATENTS Dunajeif 10250 Rouse 1027.2 Gillon 1026 Stanly 102-50 Loedding 10249 'Snelling 1026 Pigrnan 1027.2 Pigman 1027.2
BENJAMIN A. BORCHELT, Primary Examiner.
SAMUEL W. ENGLE, Examiner.