US2470120A - Method of bombing from fast moving planes - Google Patents

Description

May 17, 1949. B. WALKER 2,470,120

METHOD OF BOMBINGr FROM FAST MOVING PLANES Filed May 6, 1943 A llllln lo -g ErnnksWalker Patented May 17, 1949 UNITED STATES PATENT OFFICE METHOD OF BOMBING FROM FAST MOVING PLANES (Granted under theI act of March. 3, 1883, as amended April 30, 1928; 370 O. G. '757) The invention described herein may be manu- 'factured and used by or for the Goverment for governmental purposes without the payment to me of any royalty thereon.

'I'his invention relates to a method of bombing from fast moving planes, a bomb construction, and launching mechanism to be used with this method.

The method pertains mainly to dropping bombs from fast moving planes, so that the bombs drop substantially vertically after leaving the plane due to a jet reaction that propels the bomb so that its horizontal velocity is substantially zero. One advantage of the jet or rocket reaction for dropping bombs vertically is the lack of recoil on the plane parts. With a bomb weighing over 100 pounds and a plane velocity of around 300 M. P. H. the force necessary to give the bomb zero horizontal velocity would be diiicult to counteract if produced in a cannon or mortar reaction device mounted in a plane. For 1000 pound bombs the problem would be aggravated in proportion. By using rocket reactions the recoil problem is non-existent and the scheme more practical of accomplishment than with spring or mortars as proposed in the prior art.

The bombs may be launched from direction controlling tubes as will be shown, or dropped from the regular bomb bays with delayed jet rearward reaction sufllcient to give the bomb a negative horizontal velocity equal to the plane forward velocity, so the horizontal velocity of the dropping bomb will be substantially zero relative to the target.

Other features of the invention are the method of launching the bombs, streamlining the launching tubes when not in use, methods of starting the jet reaction, and safety ignition devices. Another feature is a launching tube set at a substantial angle to the horizontal in the plane with jet reaction such that the horizontal velocity is substantially equal to the velocity of the plane so the bomb will fall straight down with an increased vertical velocity.

Other features of this invention will be more particularly pointed out in the attached specification and drawings in which:

Fig. 1 represents a plane incorporating one Iform of the invention.

Fig. 2 is an enlarged view partly in section of the reaction bomb and launcher of Fig. 1.

Fig. 3 is a sectional view taken on the line 3-3 of Flg. 2.

Fig. 4 is a. sectional view partly cut away show- 2 ing one form of ignition device for the jet reaction.

Fig. 5 is a small scale diagrammatic view of the action of a plane and bombs when used on a target according to the invention.

Fig. 6 is a view of a part of a plane fuselage and an inclined bomb launcher tube.

Fig. 7 is an enlarged view of part of one form of the inclined launcher tube shown in Fig. 6.

In all figures like numerals of reference refer to corresponding parts of the various views. In Figures 1 through 5 an airplane fuselage I0 carries a bomb launching tube II formed below and attached to or integral with its fuselage or it may be lowered for firing from a bomb bay as design and use dictate. 'I'his launcher preferably has streamlined closures I2 and I'3 for its ends when4 not firing. These can be operated by the pilot, bombardier or other crew memberv by power or manual control or by pedal I4 ;-which is connectedto closures I2 and I3 through arms I2A and I3A. l

If an electric initiation is used for starting the jet reaction of the bomb, this is accomplished by a battery 3U, which can be the plane battery, a switch 3l a contact and a collection plate or ring 25 on the bomb. This ring 25 is connected to a squib or other suitable ignitor for the jet reaction charge in the nose of the bomb 20. The jet of the rocket charge in the bomb is faced forward in the bomb in the direction the plane is traveling. A safety feature is provided in the switch 32 which only completes the circuit to ground when the pedal is in the position to open the closures I2 and I3. One side of the battery could be grounded and a two point switch where 32 is located could complete the circuit to the bomb. The bomb is preferably formed with fins 2I at the rear, opposite the jet reaction. During the jet reaction after the bomb leaves the tube I I the air stream passing the bomb as it loses its plane velocity will be opposite the jet reaction. In the subsequent fall of the bomb the tail fins will make the jet reaction nose fall rst. A suitable tail fuse with an arming wire 23 and arming propeller 22 may also be applied as desired.

In using this invention the pilot can hedge hop at low elevations or higher as desired until over his objective, then with the pedal I4 forward to open the tube or closures I2 and I3 he presses the switch 3| and the rocket jet of the bomb will propel it rearward relative to the plane afl; a velocity equal to the forward velocity of the plane and the bomb will drop straight down on the target. This is particularly desirable when bombing by links I5 and ls A certain marine targets that can be best seen by observation from directly above. Fig. 5 shows a plane using this tactic to bomb a bridge directly below the plane.

In Figs. 6 and 7 I have shown an inclined bomb launching tube 40 in a plane I0 adapted to obviate inteference with the streamlining of the plane.

This tube 40 has a rotating port closure 4I through which a bomb can be loaded. The tail of this bomb is on the same end as the rocket orice. This bomb gets vertical velocity from the rocket reaction as Well as a horizontal component of velocity about equal to the horizontal velocity of the plane. This would be desirable where penetration is desired from low altitudes. The usual safety wire and time delay or safe dropping features which are well knownfcan be incorporated. In considering the practice of my invention it should be borne in mind that the forward progression of the modern airplane and the functioning of its propellers produces a slipstream, or mass of air, moving rearwardly at high velocity not only with respect to the plane itself, but also, usually, with respect to the ground. Of course, the factor of drift of air bodies, and wind speed aiect this, but it may be assumed that in the practice of my invention the aircraft may be brought over the target while progressing with or against the prevailing wind, so that the wind factor is either negative or positive in the direction in which the plane is moving. Under either of these last named conditions the slipstream will move rearwardly relatively to the ground. The decelerating charge or other decelerating means by which the bomb is moved from the launching may be proportioned to the requirement of the wind factor so that the bomb reaches substantially zero velocity horizontally. It will be understood that notwithstanding the zero velocity of the bomb with respect to the earth the slipstream is still acting upon the tail ns so as to preserve dynamic stability in the bomb, preventing momentary erratic movements which might otherwise occur if it were not in the slipstream. While this stabilizing continues acceleration by gravity begins, and functioning of the tail iins to bring the bomb onto a vertical axis becomes eiective.

While I have shown preferred forms of the invention many modifications will be evident and `all uses as pointed out here and in the attached claims are a part of this invention.

I claim: 1. The method of bombing a target from an `airplane in ight which comprises jet propelling a bomb from the airplane when substantially directly above the target with a horizontal velocity substantially equal and opposite to the horizontal velocity with which the airplane is passing over the target, said jet propelling means acting for a substantial period of time after said bomb leaves the support of said airplane.

2. The method of bombing'from an airplane in night, using a bomb positioned within a tube fixed to said airplane, and having a nose portion containing jet propelling means and a trailing tail portion, which comprises launching said bomb' by said jet propelling means with its longitudinal axis horizontal, tail portion first and away from the rear of such airplane with a rearward component of motion relativel to said airplane but substantially static in relation to the earth, said jet propelling means acting for a substantial period `of time after said bomb leaves the support of said airplane and imparting to said bomb a velocity substantially equal to and `,opposite to the velocity of said plane, said jet propelling means producing substantially no reaction on said airplane. Y

3. A method of bombing from a fast moving airplane which consists in imparting a rearward velocity to said bomb by jet reaction, part of said rearward jet reaction taking place while said bomb is supported by said airplane and the majority of said jet reaction on said bomb taking place after said bomb leaves the support of said airplane, the net velocity of said bomb relative to the earth in a horizonal direction after termination of said jet reaction being substantially zero.

BROOKS WALKER.

REFERENCES CITED 'Ihe following references are of record in the le of this patent:

UNITED STATES PATENTS Number Name Date 502,713 Gathmann Aug. 8, 1893 511.418 Gathmann Dec. 26, 1893 1,186,023 Moore June 6, 1916 1,294,240 Cooke Feb. 11, 1919 1,621,654 Boos Mar. 22, 1927 1,734,501 Schwoebel Nov. 5, 1929 1,758,170 Parker May 13, 1930 2,382,016 Love Aug. 14, 1945 FOREIGN PATENTS Number Country Date 854 Great Britain 1913 79,542 Austria Dec. 29, 1919 328,847 Italy Aug. 22, 1935 374,785 Italy Sept. 8, 1939 437,399 France Feb. 16, 1912 463,601 France Dec. 20, 1913` 702,040 Germany Jan. 30, 1941 'i 804,838 France Apr. 10, 1936 832,464 France July 4, 1938 OTHER REFERENCES Popular Mechanics, October 1942, page 45.

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