US2991815A - Elastic bag for aerial delivery - Google Patents

Description

July 11, 1961 P. o. PFEIFFER 2,991,815

ELASTIC BAG FOR AERIAL DELIVERY Original Filed Dec. 17, 1951 2 Sheets-Sheet 1 F 5 INVENTOR 7' Paul 0. Pf'eif'fer ATTORNEYS y 1961 P. o. PFEIFFER 2,991,815

ELASTIC BAG FOR AERIAL DELIVERY Original Filed Dec. 17, 1951 2 Sheets-Sheet 2 INVENTOR Paul 0- Pleifler BY Cam 0% ATTORNEYS United States Patent 2,991,815 ELASTIC BAG FOR AERIAL DELIVERY Paul 0. Pfeifier, Akron, Ohio, assignor to The General Tfirg Rubber Company, Akron, Ohio, a corporation 0 0 Application Aug. '30, 1956, Ser. No. 607,185, which is a continuation of application Ser. No. 262,116, Dec. 17, 1951. Divided and this application Aug. 1, 195"], Ser. No. 675,981

9 Claims. (Cl. 150-1) The present invention relates to an article of manufacture. Specifically, it relates to a strong, flexible, elastic bag which may be filled with flowable material and dropped to the ground.

This application is a division of my copending application, Serial No. 607,185, filed August 30, 1956, which is a continuation of my application, Serial No. 262,116, filled December 17, 1951, now abandoned.

A most pressing military supply problem is to supply isolated pockets and units of men with provisions, particularly liquids, such as gasoline and water. This must be accomplished from the air. In such cases, the transporting plane delivers the goods by landing in the area or by dropping containers by parachute. Often there is no landing area, and the supplies must be dropped by parachute.

Parachute droppings have several disadvantages. If there is any wind, the parachutes tend to blow and drift for mile. When they do land, they are often hung up in trees and are difiicult to reach. Finally, it is a very expensive method of supply in that the parachutes themselves are expensive and are seldom recovered and they occupy considerable space in the plane delivering the goods and thereby reduce the net pay load of supplies in the plane.

The elastic bag of the present invention permits dropping of flowable material at high velocity from an airplane flying at high altitudes so that the material may be dropped without substantial inaccuracy due to wind forces. Such a method of delivery is unusual and very practical since it does not require parachutes or other heavy equipment to reduce the velocity during fall and does not require complicated or expensive equipment. According to the present invention, a strong flexible elastic bag or container is provided having elastic top and bottom walls which may be stretched a substantial amount radially. This bag is filled with liquid or freely flowing fineparticles and while so filled is dropped from an airplane at a substantial altitude and allowed to fall at high velocity. Means are provided for stabilizing the bag during its fall to cause the container to strike the ground with its axis upright, so that the elastic top and bottom walls of the container can absorb the impact with the ground without bursting the container or losing its contents. The bag is stabilized while it falls at high velocity so that its axis remains upright during the fall. The stabilizing step is performed by means carried by the container which does not add materially to the Weight of the container.

The container may be shaped to provide the necessary stabilizing means or may be provided also with auxiliary stabilizing means. A suitable stabilizing means may be provided by shaping the bottom wall of the container so that it presents a convex surface when the container is,

filled and freely falling. Such a convex surface inherently tween the wings of an aircraft so as. to maintain the conhas the same self-righting effect as the dihedral angle betainer in its upright position during its free fall. The vertical projection of any side dropping below level increases as the projection of the opposite side rising above center decreases, resulting in a corresponding shift in wind pressure which in turn causes the container to right itself and equalize the wind pressure about the convex surface.

When the container is dropped as indicated above, it

Patented July 11, 1961 contents of the container can then be removed through a convenient plug or valve, or stored in the container until desired for use.

An object of the present invention is to provide an article for delivering supplies from air vehicles vto the ground receivers in freely falling containers.

A further object of the invention is to provide a container which is stabilized during fall so that its velocity is limited without the need for heavy parachutes or the like and so that the container can absorb an impact with the ground at high velocity.

Another object of the invention is to provide a container which may be dropped at high velocity so that it will land at the desired location.

Another object of the present invention is to provide'a container which is so shaped and constructed that it can be filled with liquid or the like and dropped from great heights and land without bursting and with its contents intact.

A still further object of the invention is to provide containers which yieldingly resist and absorb the large impact forces arising when such containers strike the ground.

Other objects and advantages of the invention will become apaprent from the following detailed description and from the accompanying drawings illustrating this invention, in which like numerals relate to like parts throughout the several views.

FIGURE 1 is a front elevation, partially in cross section, of a container constructed in accordance with the present invention.

FIGURE 2 is a top plan view of a quarter of the container of FIG, 1;

FIGURE 3 is a front elevation, partially in cross sec tion, of the container of FIG. 1, filled with liquid; i

FIGURE 4 is a cross-sectional detail of the middle juncture of the subject container;

FIGURE 5 is an illustration of the change in shape taken by a loaded container as its strikes the ground, the container being shown in solid lines to show its shape during free fall and at the first instant of impact, and in dotdash lines to show its shape as it stretches radially to absorb the im act;

FIGURE 6 is a front elevation, partially in cross section of a second form of container constructed in accordance with the subject invention;

FIGURE 7 is a front elevation, partially in cross section, of the container of FIG. 6 filled with liquid; and

FIGURE 8 is a detailed enlargement, in cross section, of the valve for the container of FIG. 6.

In accordance with the present invention, a container is filled with flowable materials such as gasoline, water, dry powders, or freely flowing fine particles, such as sugar, salt, flour, and the like, and then dropped from an air'vehicle to the ground. Persons on the ground serving as receivers collect the containers and empty them. Any suitable air vehicle, such as .an airplane, helicopter, balloon, or dirigible may be used. The containers may be filled either on the ground or in the vehicle. It is contemplated that this process may be used in both military and civilian work to supply persons in isolated positions. It is also contemplated that containers may be dropped from air vehicles onto the ocean or inland lakes.

The container of this invention is a relatively thinwalled hollow body and preferably has filling means'or a plug in the top portion, generally in the center thereof. The container shape should be rounded and curving and have no sharp corners or stress concentration points. Ex-

cellent results may be obtained where the container is 'a preferred type of container is symmetrical about its vertical axis so as to have a substantially uniform radial cross section throughout its circumference. The container can be molded in one piece or formed of two disc pieces integrally joined at the edges or otherwise manufactured.

The container may be generally spheroidal or ellipsoidal and is preferably oblate or depressed at the poles so that it has a diameter several times its axial height. Best re- 'sults are obtained where the container, when in the filled condition and resting on a horizontal support has high oblateness and is generally in the form of an oblate ellipsoid of revolution having a horizontal width or diameter that is at least five times the axial height of the container, the convex bottom portion of the container preferably having less curvature than and a blunter profile than the convex top portion of the container.

The containers themselves are subject to extreme forces and are constructed in accordance with definite limitations. In the first place, it is assumed that, in the great majority of drops, the containers will reach their maximum or terminal velocity as they fall to and before reaching the ground. Thus they will normally strike the ground after they reach their terminal velocity. To minimize the impact forces, therefore, the container is designed to have a minimum terminal velocity and to have as much air resistance as can be incorporated therein without being unduly complex, costly, heavy to transport, bulky or cumbersome. The containers are designed to have maximum free fall velocities (terminal velocities) below 300 feetper second and preferably around 100 feet .per second or below. The container is shaped to facilitate aiming and directing on a predetermined flight course and to minimize spinning and whirling in the air or other factors which would tend to cause the container to fall in an erratic fashion.

It will be understood that the term terminal velocity as used in the specification and claims means the maximum velocity of the container when it is allowed to fall freely from a height greater than that necessary to allow the container to reach such velocity. The terminal velocity is, therefore, determined by the air resistance of the container rather than the height from which it is dropped.

One form of container or bag constructed in accordance with the subject invention is illustrated in FIGS. 1 to 5. This bag 10 comprises a circular top sheet or disc 1 which interlocks with a circular bottom sheet or disc 2 at seam 3. As shown in FIG. 4, the edge 4 of sheet 2 laps over the edge 5 of sheet 1 and they are vulcanized or cemented together to provide an integral construction. At the top of the bag is a filling means or check valve 6 with a 'cover 7, said valve being constructed so that the liquid in the container cannot escape. A suitable construction is shown in US. patent application Serial No. 244,382, filed August 30, 1951, by Clarence H. Nefi, now Patent No. 2,677,388. The valve cover is tied to the bag by a string or lanyard 8.

The inner side of each sheet 1 and 2 should be resistant to aromatic liquids if used to transport gasoline or other chemicals. As herein shown, the inner side of each sheet 1 and 2 has a thin layer 9 of rubber-like material, such as Hycar, Thiokal, or the like, which is resistant to aromatic organic liquids so that gasoline can be transported therein without injury to the bag walls. The inner lining preferably is more flexible than the bag walls proper so that the lining does not absorb shock forces or become separated from the walls.

The material used in making the container 10 should be tough, abrasion resistant and flexible. Suitable materials are natural and synthetic rubbers and other rubberlike materials. The required physical characteristics of the material must be adapted to the goods transported in the container taking into account their specific gravity, solvent action, compatibility, and sanitation requirements of the goods.

A suitable material must satisfy a combination of several requirements in as even a balance as possible. The material has to be elastic and stretchable in order to give and distort on landing and thereby absorb and dis sipate the landing forces. At the same time, its modulus of elasticity should be suflicient so that the container, when filled, retains its shape on the ground and the walls do not collapse. The elastic bag preferably should have suflicient rigidity in the filled state so that it can be stacked readily and moved about. Preferably, it should be shaped and of sufficient rigidity so that the filling means or plug 7 can be removed while the bag 10 is resting on the ground and so that the contents of the bag will not be forced from the opening. The material forming the bag 10 should also have a sufiicient modulus of elasticity so that the shape of the container during free fall is one providing maximum air resistance and is not distorted to a streamline, teardrop shape. The material also should have toughness and abrasion resistance to stand handling and resist ground hazards, such as trees, rocks, and stubble. The walls of the container used in accordance with the present invention should have no unstretchable, continuous, reinforcing material therein because this unduly limits the flexibility and elongation of the bag.

The shape and construction of the container 10 and its elastic rubber walls 1 and 2 will be apparent from the drawings. The container 10, when filled and resting on a fiat horizontal support as shown in FIG. 3, assumes substantially the shape of an oblate ellipsoid of revolution substantially symmetrical about a vertical axis in which the top and bottom discs 1 and 2 are convex or bowed outwardly. If the discs 1 and 2 are laid substantially flatwise against one another, the overlapping disc 2 has a greater diameter than the other as is apparent from the drawings.

The container may be stabilized during its free fall in different ways to cause the container to land with its axis upright. Such a stabilizing step preferably is performed by lightweight means carried by the container itself; for example, by shaping the bottom and marginal portions of the container in such a manner that the axis tends to remain upright during the fall.

The container 10 shown in FIGS. 1 to 5 and the equivalent container 12 shown in FIGS. 6 to 8 of the drawings preferably are shaped to provide means for stabilizing the filled container during its free fall. Such stabilizing means minimizes the terminal velocity of the container, minimizes the landing shock and stresses on the container, and causes the container to land in its normal upright position so as not to injure the valve or plug for filling and emptying the container. The stabilizing means will be further described as applied to the container of FIGS. 1 to 5, it being understood that identical means may be employed with the container 12, the claims appended hereto being drawn to cover both containers.

In order to stabilize the filled container 10, the bottom of the container opposite the filling valve 6 and the portron near the maximum horizontal diameter of the container is shaped so that said container, when filled and freely falling, provides increasing air resistance on one side as it is tilted earthward from the horizontal. The outer portions of the cross-sectional curve of the contamer preferably are made to be fiat (straight), or concave, or only slightly convex when the container is freely falling, for example as shown in FIG. 5, so that when tilted from the horizontal, the air resistance of the upward portion will decrease and the air resistance of the lower portion will increase. This provides a self-righting effect similar to the dihedral angle in airplane wings. The shape of the stabilizing means at the margins of the filled container 10 is clearly shown in FIG. 4, and the convex shape of the bottom wall 2 is clearly shown in FIG. 5. As herein shown the profile (or radial vertical cross section) of the wall 2 of the container 10 ad- .jacent the maximum horizontal width or diameter (margin) when the container is in the filled condition approximates a straight line as will be apparent from FIGS. 4 and 5. The convex shape of the bottom wall 2 of the container provides means for stabilizing the container so that it remains in an upright position as it falls.

The action of the container or bag upon striking the ground is illustrated in FIG. 5. At position A, shown in solid lines, the filled .bag 10 is shown just touching the ground at the instant the bag first strikes the ground, this also representing the shape of the bag as it appears during its free fall. As shown, this shape is substantially lenticular, the filled oblate bag retaining its high ellipticity as it falls. A few instants after initial impact with the ground, at position B shown in dot-dash lines, the bag 10 has increased contact, and the liquid is beginning to spread out horizontally. A few instants later, at position C shown in dot-dash lines, the bag 10 has flattened like a pancake as the liquid moves outwardly in radial directions from the center of impact. Here the bag is severely tensioned as the energy of the liquid is absorbed. Prior to striking the ground, however, the energy is converted into forces which may be resolved into vertical and horizontal forces. The ground absorbs the vertical forces and the bag absorbs horizontal forces. The elastic material forming the bag side walls therefore must be strong enough to absorb and dissipate these horizontal forces-that is, all the forces not absorbed by the ground.

7 The material for the container 10 can be any highabrasion-resistant, nervy, flexible rubber or rubber-like material, such as natural rubber, butadiene and isobutylene copolymers, polyvinyl alcohol, and other elastomeric materials. The material should be compounded to provide high abrasion resistance and toughness. Minimum elongation at break should be 400' percent. The bag wall section, regardless of thickness, ought to pull 2000 p.s.i. or above at 500 percent elongation. In general, the thickness of the bag walls may be reduced as the modulus of the material employed to make the walls increases, and vice versa. A container having a wall pull of 4000 psi. at 500 percent elongation would be suitable. A rubber stock preferably should have 25 parts or more of a reinforcing carbon black or equivalent to provide toughness, hardness, abrasion resistance, and resistance to cutting. High quality tire tread stock satisfying the above-noted physical characteristics is suitable for use in the containers of the present invention.

It is contemplated that bags constructed in accordance with the subject invention Will have a capacity of five, ten, twenty-five, or even more gallons. Using the same stock, the bag wall thickness should be increased when the bag is used to drop heavy liquids, such as water, instead of lighter liquids, such as gasoline or the like.

To illustrate this invention, a container similar to the one disclosed in the drawings was made up of a high quality tread compound of five gallon capacity. This compound had a modulus of elasticity of 4000 p.s.i. at 500 percent elongation and a hardness of around 60 durometer. The wall thickness was 0.156 inch. Such a drum, filled with water, was dropped from an airplane at an altitude of 2000 feet. The drum landed uninl'llled and was drained of the water. Computations showed that the terminal velocity should have been reached after approximately 750 feet of fall so that the container reached its terminal velocity before striking the ground and must have struck the ground at its terminal velocity. Thus the container was subjected to no more severe conditions if dropped from 3000, 4000, or 5000 ft. altitude.

It will be noted that the elastic top wall 1 radially outwardly of the valve 6 and the elastic bottom wall 2 are free of inextensible reinforcement even at the seam 3 so that the bag 10 can readily be stretched radially. However, since .the valve 6 prevents stretching of the central portion of the top wall, it is often preferable to prowide extra material in the top wall of the bag--.-to facilitate stretching thereof. FIGURES '6, 7 and 8 show a modified form of container 12 which may be identical to that of FIGS. 1 to 5 except for the amount of rubber in the top wall. As shown in FIG. '6, the empty rubber bag 12, when collapsed and resting on a flat horizontal support, has a circumferential hump portion 11 around the top portion of the bag adjacent the filler means due to the fact that the top wall of the container has a greater external diameter than the bottom wall connected thereto. The hump portion 11 provides extra stretchable material for the top portion of the container so that it can stretch evenly with the bottom portion, or in other words, so that the top and bottom portions of the container have approximately the same area of stretchable material. The fitting around the plug 13 is unstretchable and reduces the-effective stretch of the top portion of this container. Thus an annular hump 11 can be provided to equalize this situation. When the container 12 is filled, the hump 11 is preferably substantially eliminated as seen from FIG. 7.

The filling means for the container shown in FIGS. 6 to 8 may be the same as in FIGS. '1 to 5; but, as herein shown, the filling means comprises a plug '13 which screws into the socket means 1-4 mounted in the center of the top portion of the container. The plug and socket means are preferably of a molded, shock resistant polymeric plastic, such as a fiberglass-polyester composition. A washer 15 is inserted intermediate the plug and socket to prevent leakage.

It will be understood that the container 12 may be constructed so that it will function substantially the same as the container 10 described above, even where extra material is provided in the top wall of the bag, the bottom and marginal portions of the container preferably being shaped during free fall the same as in the container 10. The bottom wall of the container 12 is convex, when the container is filled and falling freely, so as to provide means for stabilizing the container to maintain the axis of the container in an upright position.

It will be seen that the rubber container of the present invention is made up of many elements which may be united or integrally joined. It is also apparent that the elements making up the rubber container perform several different functions. These elements provide means for enclosing the liquid, means for holding the bag in an oblate shape and for maintaining a high ellipticity, and also means for providing high air resistance and for stabilizing the bag during its free fall. The term means is used in the specification and claims in the broad sense in accordance with the patent laws and is not used in the limited sense to cover only those means which perform a plurality of functions and are shown specifically in the drawings.

It is to be understood that the invention disclosed can be carried out in a number of ways within the scope of the appended claims and that it is not to be limited to the specific embodiments which are herein described for purposes of illustration. I

Having described my invention, I claim:

1. A container for aerial delivery of liquid to the ground from an air vehicle traveling at substantial altitude comprising an extensible elastic rubber bag with a volumetric capacity of at least five gallons having means comprising thin marginally connected generally circular top and bottom walls which may be extended several times their normal diameter, the rubber of said walls containing a reinforcing .carbon black and being capable of withstanding a tension of at least 2000 pounds per square inch when elongated 500 percent, the rubber marginal portion of said bag uniting the top and bottom walls being radially stretchable and stretching with said top and bottom walls when the bag strikes the ground, said bag when completely filled with said liquid and resting on a fiat horizontal surface having an axial height no greater than one-fifth the horizontal width of the container, filling means for the bag forming a part of said bag, the marginal and bottom portions of said bag maintaining the filled bag generally in the shape of an oblate ellipsoid of revolution, said bottom wall providing substantial air resistance to reduce the terminal velocity of the bag during free fall, said marginal portion of said bag having a radially outwardly projecting portion of readily stretchable material forming part of the bag walls and extending along the periphery of said bag at the junction of said top and bottom walls, and a liner of elastic rubber-like material that is resistant to aromatic organic liquids, said liner fitting within the bag and being more readily extensible than said walls.

2. A free falling droppable container for aerial delivcry of free-flowing material to the ground from an air vehicle traveling at substantial altitude comprising an elastic rubber bag which may be extended radially several times its normal diameter, said bag comprising means having a volumetric capacity of at least five gallons and having thin marginally united top and bottom generally circular wall portions of an elastic rubber material which withstands a tension'of at least 2000 pounds per square inch when elongated 500 percent so that the bag may be stretched radially to absorb landing forces, filling means near the center of said top wall whereby the bag may be filled and emptied, said top and bottom wall portions being free of inextensible reinforcement radially outwardly of the filling means and free to stretch radially, the bag when filled with at least five gallons of a liquid hydrocarbon and resting on a flat horizontal surface having an axial height no greater than one-fifth its diameter, the bottom wall being generally flat when the bag is empty and said bottom wall is unstressed and being convex when the bag is filled with liquid, the convex bottom wall having a central portion that increases in curvature from the center radially outwardly and a marginal portion that increases in curvature from the margin of the bag radially inwardly to said central portion, whereby the bottom wall assists in stabilizing the freely falling bag and faces the ground throughout the fall of the bag, said bottom wall providing the bag with a large air resistance relative to the weight of liquid and with a terminal velocity of not substantially more than 100 feet per second, and a liner of an elastic rubber that is resistant to aromatic organic liquids fitting against the walls of the bag and enclosing the liquid therein.

3. A free-falling droppable container for aerial delivery of gasoline to the ground from an air vehicle traveling at substantial altitude comprising an elastic rubber bag which may be stretched radially several times its normal diameter, said bag having generally circular top and bottom wall portions integrally joined by an annular marginal portion and having a volumetric capacity of at least ten gallons, said top, bottom and marginal portions comprising an elastic rubber material which pulls at least 2000 pounds per square inch when elongated 500 percent to enable said portions to stretch radially and absorb impact forces when the bag strikes the ground in an upright positon, means near the center of said top wall for filling and emptying of said bag, said bag being free of inextensible reinforcement radially outwardly of the filling means, the wall portions and marginal portions of the bag causing the bag to have an oblate shape when the bag is filled with gasoline and falling freely and to have a large air resistance limiting the terminal velocity of the bag to not more than 100 feet per second, said bag when filled with gasoline and resting on a horizontal surface having an axial height not more than one-fifth its diameter, the interior portion of said bag enclosing and contacting the gasoline being formed of an elastic rubber-like material that is resistant to aromatic organic liquids.

4. A container as defined in claim 3, wherein said means for filling the bag consists of non-metallic polymeric material.

5. A free falling droppable container for aerial delivery of gasoline to the ground from an air vehicle traveling at an altitude of several thousand feet comprising an extensible elastic rubber bag with a volumetric capacity of at least five gallons having generally circular top and bottom wall portions overlapped at the margins and integrally joined to provide a thickened annular marginal portion that projectsradially outwardly when the bag is filled with liquid, said top, bottom and marginal portions comprising an abrasion-resistant elastic rubber material containing a reinforcing carbon black and capable of pulling 4000 pounds per square inch when elongated 500 percent to enable said top, bottom and marginal portions to stretch radially and absorb impact forces when the bag strikes the ground at its terminal velocity, means near the center of said top wall for filling and emptying of said bag, said bag when filled with liquid and resting on a fiat horizontal surface having an axial height no greater than one-fifth the horizontal diameter of the container, the wall and marginal portions of said bag maintaining the filled bag in an oblate shape during its fall and limiting the terminal velocity of the bag during free fall to no more than feet per second, and a liner of elastic rubber-like material that is resistant to aromatic organic liquids, said liner fitting within the bag and enclosing the liquid.

6. A free falling droppable container for aerial delivery of gasoline to the ground from an air vehicle traveling at substantial altitude comprising an elastic rubber bag which may be stretched radially several times its normal diameter, said bag having generally circular top and bottom wall portions integrally joined by an annular marginal portion and having a volumetric capacity of at least 10 gallons, said top, bottom and marginal portions being formed of an abrasion-resistant carbon-black-reinforced elastic rubber material which may be elongated 500 percent and which is capable of withstanding a tension of 4000 pounds per square inch to enable said portions to stretch radially and absorb impact forces when the bag strikes the ground, means near the center of said top wall for filling and emptying of said bag, said bag being free of inextensible reinforcement radially outwardly of the filling means, said bag when filled with gasoline and resting on a fiat horizontal surface having a high oblateness and an axial height no greater than onefifth the horizontal width of the container, the wall and marginal portions of the bag maintaining the high oblateness of the filled bag during its free fall and providing substantial air resistance to limit the terminal velocity of the bag during free fall to no more than 100 feet per second, the interior portion of said bag enclosing and contacting the gasoline being formed of an elastic rubberlike material that is resistant to aromatic organic liquids.

7. A container as defined in claim 6 wherein the marginal portion of the bag includes means for stabilizing the bag to maintain the axis thereof in an upright position during its fall.

8. A free falling droppable container for aerial delivery of gasoline to the ground from an air vehicle traveling at substantial altitude comprising two substantially flat circular sheets of tough abrasion-resistant elastic rubber joined at their margins to provide a hollow radially extensible bag with a capacity of at least five gallons having a thickened annular marginal portion, the rubber of said sheets being reinforced with carbon black and being capable of withstanding a tension of at least 2000 pounds per square inch when elongated 500 percent, said marginal portion projecting radially outwardly and having an outside diameter at least five times the axial height of the bag when said bag is filled with liquid and resting on a flat horizontal surface, shock-resistant polymeric filling means for the bag forming a part of said bag, the wall and marginal portions of the bag maintaining the filled bag in a generally lenticular shape and limiting the terminal velocity during free fall to no'more 9 than 100 feet per second, the bottom wall of the filled bag being convex and having a downwardly bowed cross section decreasing in radius of curvature adjacent said marginal portion, and a liner of elastic rubber that is resistant to aromatic organic liquids fitting within the bag and enclosing the liquid therein.

9. A free falling droppable container for aerial delivery of gasoline to the ground from an air vehicle traveling at substantial altitude comprising an extensible elastic rubber bag with a volumetric capacity of at least five gallons having thin marginally connected generally circular top and bottom walls which may be extended several times their normal diameter, the rubber of said walls containing a reinforcing carbon black and being capable of withstanding a tension of at least 4000 pounds per square inch, the rubber marginal portion of said bag uniting the top and bottom walls being radially stretchable and stretching with said top and bottom walls when the bag strikes the ground, said bag when filled with gasoline and resting on a flat horizontal surface having an axial height no greater than one-fifth the horizontal width of the container, filling means for the bag having an opening at the wall of the bag to permit filling of the bag and means for closing said opening, means including the wall and marginal portions of said bag maintaining the filled bag in an oblate shape during its free fall and limiting the terminal velocity of the bag during free fall to no more than feet per second, and a liner of elastic rubberlike material that is resistant to aromatic organic liquids References Cited in the file of this patent UNITED STATES PATENTS 685,894 Williams Nov. 5, 1901 1,166,862 Smoot Jan. 4, 1916 1,335,467 Traynor Mar. 30, 1920 1,340,236 Moeble May 18, 1920 1,834,978 Shapiro Dec. 8, 1931 2,209,570 Kraft July 30, 1940 2,406,903 Rethorst Sept. 3, 1946 2,423,940 Krupp July 15, 1947 2,430,905 Bradley Nov. 18, 1947 2,641,292 Quillinan June- 9, 1953 2,724,418 Krupp Nov. 22, 1953 2,784,755 Bender Mar. 12, 1957 OTHER REFERENCES Marks Handbook, third edition, page 760, published 1930 by McGraw-Hill Book Co., NY. (Copy in Div.

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