US3183904A - Water injection for ejection performance boost - Google Patents

Description

May 18, 1965 E. J. BARAKAUSKAS WATER INJECTION FOR EJECTION PERFORMANCE BOOST Filed Jan. 25, 1963 CONTROL F/G. Z

EB E L BQ I OF WATER TIME INVENTOR Edward J; Bamlrauskaa B WM/ FIG. 3'

ATTORNEY United States Patent 3,183,904 WATER INJECTION FOR EJECTION PERFQRMANCE BOOST Edward J. Barakauskas, Saratoga, Calif., assignor, by mesne assignments, to the United States of America as represented by the Secretary of the Navy Filed Jan. 25, 1963, Ser. No. 254,825

1 Claim. (Cl. 124-41) The present invention relates to a method and apparatus for launching missiles and is particularly directed to that type missile which is launched from an underwater position.

At the present, the ejection system for launching the underwater missile is limited to a keel depth range of feet from the nominal launch depth. With a fixed pressure air system, the same air flow rates are utilized independent of the keel depth of the submarine. At the shallow limit of the keel depth range, the crushing loads on the missile after missile exit limits the amount of air that can be used for ejection. As the keel depth is increased, the missile velocity obtained from that amount of air decreases. At 20 feet greater depth the velocity decreases to the minimum within the specified missile velocity criteria. If the depth is increased further, the velocity falls below the specified velocity range.

A significant improvement in missile launching can be achieved if the range limits for launching can be opened up to :20 feet from the nominal keel depth because the keel depth is very difiicult to control as the ship is hovering during the launching process.

Previous approaches to increasing the keel depth range have been directed towards methods of decreasing the exit pressure at the shallow depths. In such prior systems suflicient air is provided in the launch flask to launch at the deep depths. When the submarine is at the shallow limit of the keel depth band, means are provided to decrease the exit pressure to alleviate the missile pressure loadings. Of several methods the most feasible is to close the air valve while the missile is moving up the launch tube and thus limit the air entering the tube and thereby the exit pressure. Hardware for accomplishing this function has been found to be feasible by virtue of preliminary operational tests. Such a system involves a large amount of hardware and is subject to aborting missile launches in the event of a malfunction.

It is an object of the present invention to operate the compressed air ejection system at pressures which are compatible with the missile pressure loadings at the shallow depth limits when the launching is at the :20 feet keel depth range and to inject additional energy into the launch tube during launchings at greater depth limits.

It is a still further object of the present invention to inject, simultaneously with the compressed air, means of increasing the temperature within the launch tube to provide the additional energy necessary to launch the missile from the greater keel depth.

It is a still further object of the present invention to provide additional energy during the launching movement in a form which due to the temperature drop caused by the expansion of the compressed air will produce a freezing action on water injected therein and in freezing such water will liberate suificient heat to provide energy for increasing the linear speed of the missile.

It is a still further object of the present invention to provide an apparatus including means for injecting compressed air and water into the launching tube at a zone or level below the missile, the subsequent expansion of the compressed air therein causing a drop in temperature sufficient to freeze the water, the freezing of the water liberating heat to provide the additional energy.

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Other objects, advantages and novel features of the invention will become apparent from the following detailed description of the invention when considered in conjunction with the accompanying drawings wherein:

FIG. 1 is a diagrammatic view of the launch tube and associated control apparatus.

FIG. 2 is a diagrammatic view of the same apparatus showing a different control arrangement, and

FIG. 3 is a graph indicating the drop in temperature plotted against time.

Referring particularly to FIGS. 1 and 2 wherein like reference numbers denote like parts throughout theseveral views, a launch tube 5 houses a missile 6. A source of compressed air 7 is connected through pipe 8 to the launch tube 5 at a point below the missile. A source of water 9 is connected by pipe 11 to the tube and by pipe 12 to the source of compressed air 7.

A valve 13 located in the air line 8 controls the flow of air from the source 7 to the tube 5, While a valve 14 located in the water line between the water source and the air source controls the injection. of the water into the launch tube. These valves are connected to a control mechanism 18 in a manner to be operated simultaneously at the time of launching of the missile, when the launching takes place at the deep depth. When at shallow depth, the valve 14 is closed and the water is not drawn into the tube. This tends to compensate for the difference in keel depth approximately :20 feet. Referring particularly to FIG. 2 a similar apparatus is shown with the difference that the line 16 connecting the source of water with the source of air is connected into the air line on the launch tube side at the point 17. The water is then injected into the launch tube by the pressure differential between the pipe and the launch tube. Here again, the valve 14 is used to shut off the water for shallow launch and is opened for a deep launch.

The graph shown in FIG. 3 is illustrative of the drop in temperature.

During the latter half of the ejection cycle, the air in the launch tube gets very cold because the air in the launch tube expands doing work and the air coming in from the launch flask is very cold since it has expanded in the flask from a high to a low pressure. The injection of water during the launch cycle will have no effect until the air temperature drops below the freezing point of water. After this occurrence, the water freezes liberating heat, and prevents the temperature from dropping as far as in the waterless launch situation. By adding energy the temperature and pressure of the air is increased, increasing the missile acceleration and velocity. An increase of missile velocity of 7 fps. has been observed when water is present. This is suflicient to extend the keel depth range for launching by the desired 20 feet.

What is claimed is:

A missile launching apparatus for increasing the energy of launching comprising:

a launching tube closed at its bottom end and having a missile supported in said tube and spaced from said bottom end;

a compressed air delivery tube secured. to and communicating with the tube adjacent the bottom end;

a tank delivering compressed air to said delivery tube;

a valve in said delivery tube between said tank and said launching tube to control the delivery of said compressed air to the launching tube;

a tank containing water;

a water delivery tube connected to said launching tube directly below the bottom end of said missile;

a tube connecting said water tank with said compressed air tank;

' 3 a valve in said connecting tube to control the passage of compressed air from said compressed air tank to said water tank; a mechanism controlling the actuation of each of said valves; whereby compressed air and water are delivered to the space at the bottom of the launching tube as desired, the resultant movement of the missile in the tube increasing the volume of the closed chamber causing an expansion of the air resulting in atem- 10 consequent freezing of the water liberating the latent heat of fusion, the energy of said liberated heat adding to the energy of launching.

References Cited by the Examiner UNITED STATES PATENTS 1,526,256 2/25 Techel 114--238 2,989,899 6/61 Siegel et al. 89--1.7 3,088,377 5/63 Siegel 89--1.7

BENJAMIN A. BORCHELT, Primary Examiner.

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