US2347412A

US2347412A - Self-defensive lighter

Info

Publication number: US2347412A
Application number: US419474A
Authority: US
Inventors: Higgins Andrew Jackson
Original assignee: Individual
Current assignee: Individual
Priority date: 1941-11-17
Filing date: 1941-11-17
Publication date: 1944-04-25
Anticipated expiration: 1961-04-25

Description

April 25, 1944.

A. J. HIGGINS SELF -DEFENS IVE LIGHTER Filed Nov. 17, 1941 2 Sheets-Sheet l gnwwrvlloz April 25, 1944. A. .1. HIGGINS SELF-DEFENSIVE LIGHTER Filed Nov. 17, 1941 2 Sheets-Sheet 2 l .P l l I Patented Apr. 25, 1944 UNITED STATES, PATENT OFFICE SELF-DEFENSIVE LIGHTER, Andrew Jackson Higgins, New Orleans, La. Application November 17, 1941, Serial No. 419,474

2 Claims.

This invention relates to a fast speed powerdriven lighter, self-defensive against attack by submarines.

One of the objects of the invention is to provide a craft of the type described in which the rear deck slopes downward toward the stern to approximately water level forming a ramp, and

in which the transom -bulwark is transversely hinged approximately at the level of the lower end of the ramp andadapted to be lowered while the vessel is in fast motion so that its free portion drags through the water, said hinged transom being then an extension of the ramp, the lighter carrying one or more fast speed combat boats supported on tethered cradles and suitably armed with depth bombs, machine guns, etc., capable of being launched down said ramp including the ramp extension while the lighter is travelling at high speed, the cradle remaining tethered.

Another object of the invention is to provide a lighter which can be driven up on the beach without the benefit of wharves or docks, and to provide combat boats of the type which can be driven under their own power on to their cradles to be hauled up again upon the deck.

Other objects of the invention will appear as the following description ,of an illustrative embodiment thereof proceeds.

In the drawings which accompany and form a part of the following specification and throughout the several figures of which the same characters of reference have been employed to designate identical parts:

Figure 1 is a side elevation partly in section;

Figure 2 is a plan view of the same;

Figure 3 is a longitudinal section on an enlarged scale of the afterpart of a lighter and the cradle carried thereby, the hinged portion of the transom being shown in broken lines in position as an extension of the ramp;

Figure 4 is a plan view of what is shown in Figure 3; and

Figure 5 is a cross section taknalong the line 5-5 of Figure 4.

Referring now in detail to the several figures, the numeral i represents in general the hull of the lighter which preferably has the shape of the boat'hull forming the subject of my Patent No. 2,144,111, granted January 1'7, 1939, and known as the Eureka hull having a transversely flat overhanging bow, the underpart of which starts with smooth curvature which merges into a dead rise or Vbottom shape, the latter con-- tinuing to a point adjacent the midship section of the hull. The rear portion of the hull has a cross section from a point forwardly of the pro- R peller and proceeding toward the stern. A hull of this shape engulfs the aerated water churned by the forefoot and travels upon an aerated film which is gradually dissipated toward thechines by the slope of the bottom in the dead rise portion. The tunnel has the function of producing a vacuum which draws solid-water up from the depths into the propeller paths avoiding cavitation. A hull of this type travels at high speed with minimum friction and with a moderateexpenditure of power. The transversely fiat shape f the bow and its overhang permits the vessel to be driven upon'a beach, permitting the landing of cargo andmen even where thereare no wharves and docks, and permitting the vessel to be retracted from the shore by its own power.

Such a vessel, particularly when made of large size, is advantageous in the interest of national defense. It is contemplated that large ships sh'all transport cargoes of defense supplies to the limits of the Western Hemisphere, as for example, oif the coast of Iceland without landin at ports which might be the targets for hostile aircraft. Here they would be met by the lighters of the present invention, one on each side 'to which the cargoes of the large ships would be transferred. The lighters, being speedy boats. would require but a few hours to make the coast of Scotland, for example. They would avoid large seaports where they might have to wait their turn for docking facilities and meanwhile be the targets for aircraft, but would run upon predetermined isolated beaches where their cargoes could be readily transferred directly to railroads.

-In the making of this run from Iceland to Scotland, for example, the lighters would be in hostile waters, subject to attack by submarines and one of the principal objects of the present invention, as has been above suggested, -is to make them self-defensive against such attack. With this end in view the lighter is provided with a rear decktion shown in Figure 3, forming an extension of the ramp 5. The free portion of the bulwark B sinks wine distance below thewater level as shown, but rides high due to the forward motion of the lighter.

The bulwark or ramp extension 6 may be oi. any desired width, but is here shown as being the full width of the stern of the lighter. The ramp 5 is provided with two pairs of tracks I and 8, each pair for receiving a cradle for the launch-- combat boats will at once move of! from the cradles and proceed in the work finding and attacking the submarine. The cradles may be hauled up the ramp by winding the cables on the ,winches, the cradles being guided in position to engage the respective tracks 1 and 8 by the upwardly tapering guide members I! and IS on the ramp extension.

When the combat boats are to be taken on board again, the cradles are lowered into position to receive them. They drive into the cradles under their own power and the cradles are ported above the ramp 5 upon cradles l4 and I5.

These cradles are provided with suitable rollers l8 which ride upon the respective tracks 1 and 8. The cradles are buoyant, being double-walled as shown with an enclosed air space between the walls and are so shaped as to receive the combat boats between their sides with the propellers I l of said combat boats free from any obstruction. The stem ends of the cradles are open'to permit the combat boats to back out therefrom or to be driven into aid cradles. Said cradles are tethered at their forward ends by the cables l8 which are wound upon power driven winches l9 and 20.

It is contemplated that the cradle will be let down the ramp including the ramp extension until a suflicient portion of the cradle floats in the water behind the ramp to permit the combat boats to be driven off in reverse under their own power. Y

.The operation is as follows: In the event that an enemy submarine is sighted or detected by sound detection devices, the screw of the combat boats will take their places and may start the power plants of the combat boats even while the latter are. in their repose position upon the cradles. Without even reducing the speed of the lighter the bulwark or ramp section 8 is let down to the position shown in Figure 3, the winches started and the cables [8 unwound so that the cradles descend until they float in the water over and aftof the rear part of the ramp extension 8. The buoyancy of the cradles is such that the rear portion of the combat boat or perhaps the entire combat boat float relative to the cradle. In the meantime, thatis to say, if time is of the essence in the launching operation, the crews of the combat boats will have put them into reverse gear so that the moving propellers strike the water in the wake of the forwardly moving boat with minimum shock to the propeller blades. The

hoisted to their normal repose position on the lighter. The ramp section 8 is raised and secured becoming a continuous part of the bulwark oi. the vessel.

It will be understood to those skilled in the art that the construction asshown and described is merely illustrative of the inventive concept and that numerous other equivalent constructions come within the purview of the invention which is defined in the appended claims.

What I claim is:

1. In combination, a vessel having a deck sloping downwardly to meet the stem at a line close to water level, forming a ramp, and having a.

transom section normally extending above said line and outwardly hinged approximately at said line whereby it can be swung outwardly and downwardly into the water to form a free floating extension of said ramp, and a buoyant launching cradle normally positioned at the top of said ramp adapted to travel on said ramp including said ramp extension, and tethered to prevent its moving substantially beyond the lower'end of said ramp extension.

2. In combination, a vessel having a deck sloping downwardly to meet the stem at a line close to water level, forming a ramp, and having a transom section normally extending above said line and outwardly hinged approximately at said line whereby it can be swung outwardly and downwardly into the water to form an extension of; said ramp, a launching cradle normally positioned at the top of said ramp adapted to travel the length of said ramp including said ramp extension, a boat on said cradle adapted to be launched therefrom, said vessel and boat being both of that type having a transversely flat bow portion merging into a dead rise hull shape from a point adjacent the bow to a point adjacent amidships and having a substantially flat bottom adjacent the stem with a tunnel extending above and forwardly of the propeller of progressively ANDREW JACKSON HIGGINS.