Air cushion vehicles

Claim 2

In an air cushion vehicle including a generally horizontal deck or the like; the combination comprising means defining a first plenum below the deck for lifting the vehicle including flexible inflatable substantially impermeable first skirt portions on opposite sides of the deck, means connecting said first skirt portions with respect to the deck such that upon inflation sections of said first skirt portions will extend in a direction outwardly of the vehicle in an arcuate shape, second skirt portions of flexible substantially impermeable material joining said first skirt portions adjacent the bottoms of said first skirt portions to extend downwardly from said first skirt portions and longitudinally along the bottoms of said first skirt portions when the latter are inflated, said first and second skirt portions including a plurality of stiffener members located at spaced intervals along said first and second skirt portions to maintain said second skirt portions in generally vertical disposition below said first skirt portions when said first skirt portions are inflated while permitting said second skirt portions to be flexible in the region between the stiffener members, said stiffener members each including a first arm joined to said first skirt portion and a second substantially rigid arm extending at an angle to said first arm and joined to said second skirt portion and extending generally vertically thereof.

Claim 3

The air cushion vehicle defined in claim 1 wherein said first skirt portions are formed by closed tubular members having a continuous generally circular cross section and wherein the pressure in said tubular members is greater than atmospheric pressure to produce an inward force on said stiffener members preventing outward movement of said lower skirt portions.

Claim 4

The air cushion vehicle defined in claim 2 wherein said first and second skirt portions are formed from flexible sheetlike material.

Claim 5

In the air cushion vehicle defined in claim 1 means defining a second plenum below the deck at the front portion of the vehicle forwardly of said first plenum, air supply means for supplying said second plenum with air, means defining a port between said first and second plenums for discharging air from said second plenum rearwardly into said first plenum for supplying said first plenum with air, said means defining said port including a partition extending transversely between said first skirt portions on the opposite sides of the vehicle generally at the bottom of the vehicle above the surface of travel and located forwardly of the center of the lifting area of the vehicle such that when the deck of the vehicle moves downwardly towards the surface of travel about the center of the lifting area of the vehicle said partition will move closer to the surface of travel to reduce the area of said port and thereby increase the pressure in said second plenum for raising the deck and vehicle to thereby provide longitudinal pitch stability to the vehicle.

Claim 6

The air cushion vehicle defined in claim 1 wherein said first skirt portions extend inwardly under the vehicle with their extremities anchored with respect to the vehicle to define part of said plenum and to enclose a space to be supplied with air to be inflated thereby.

Claim 7

In the air cushion vehicle defined in claim 5 wherein the portions of said first skirt portions which extend inwardly under the vehicle have upper and lower surfaces, said plenum being defined in part by the lower surfaces of said first skirt portions and said inflatable space being defined in part by the upper surfaces of said first skirt portions.

Claim 8

In the air cushion vehicle defined in claim 6 further including, means defining a second lift plenum at the front portion of the vehicle below the deck, a first port means communicating said inflatable space enclosed by said first skirt portions with said second plenum, second port means communicating said second plenum with said first plenum, and air supply means for supplying air into said inflatable space to flow into said second plenum and then into said first plenum.

Claim 9

The air cushion vehicle defined in claim 7 wherein said first and second port means have relatively restricted areas such that the static pressure in said second plenum is less than the pressure in said enclosed space but greater than the static pressure in said first plenum.

Claim 10

In the air cushion vehicle defined in claim 8 wherein said second port means is defined by a partition extending transversely under the vehicle adjacent the lower edges thereof and forwardly of the center of lifting area of the vehicle such that when the vehicle moves downwardly about the center of lifting area towards the surface of travel said second discharge port will be reduced in area To increase the pressure in said second plenum for raising the front of the vehicle to provide longitudinal pitch stability. 10 The air cushion vehicle defined in claim 9 wherein said partition extends upwardly towards the deck in the forward direction of the vehicle terminating below the deck to define said first port means.

Claim 11

In the air cushion vehicle defined in claim 1 wherein said second skirt portions are shallow in depth relative to said first skirt portions.

Claim 12

In the air cushion vehicle defined in claim 11 wherein the bottom edges of said second skirt portions extend linearly into reduce flow of air out of the plenum across the bottom edges for a given clearance height across the second skirts portions over the surface of travel.

Claim 13

In an air cushion vehicle having a generally horizontal deck or the like; the combination comprising, means defining a first plenum under the deck for maintaining an air cushion under the deck to lift the vehicle, means defining a second plenum below the deck generally at the front portion of the vehicle for lifting the vehicle, means for introducing air to the second plenum, and means defining a discharge port having a variable area depending on the longitudinally pitched condition of the vehicle for discharging air from said second plenum into said first plenum to supply said first plenum with air, said means forming said second plenum including side skirt portions depending downwardly from the deck on opposite sides of the vehicle, an internal transverse partition member extending transversely between opposite sides of the vehicle between said side skirt portions, said partition member having a bottom portion spaced above the lower edges of said side skirt portions to constitute said means defining said discharge port, the distance between said bottom portion of said partition member and the surface of travel being variable when the vehicle pitches longitudinally, said internal partition member having an upper portion extending adjacent to but below said deck to define an inlet port communicating with said second plenum to constitute said means for introducing air into said second plenum.

Claim 14

In an air cushion vehicle having a generally horizontal deck or the like; the combination comprising, means defining a first plenum under the deck for maintaining an air cushion under the deck to lift the vehicle, means defining a second plenum below the deck generally at the front portion of the vehicle for lifting the vehicle, means for introducing air to the second plenum, and means defining a discharge port having a variable area depending on the longitudinally pitched condition of the vehicle for discharging air from said second plenum into said first plenum to supply said first plenum with air, said means forming said second plenum including side skirt portions depending downwardly from the deck on opposite sides of the vehicle, an internal transverse partition member extending transversely between opposite sides of the vehicle between said side skirt portions, said partition member having a bottom portion spaced above the lower edges of said side skirt portions to constitute said means defining said discharge port, the distance between said bottom portion of said partition member and the surface of travel being variable when the vehicle pitches longitudinally, said internal partition member having an upper portion extending adjacent to but below said deck to define an inlet port communicating with said second plenum to constitute said means for introducing air into said second plenum.

Claim 15

The air cushion vehicle defined in claim 13 further including means for supplying air generally at a rear portion in the vehicle and conduit means extending from said last recited air supply means along the vehicle and communicating with said port for introducing air into said second plenum.

Claim 16

The air cushion vehicle defined in claim 14 wherein said conduit means is formed by flexible inflatable skirt members secured to the deck to be inflatable into an arcuate shape.

Claim 17

The air cushion vehicle defined in claim 15 wherein said inflatable skirt members define portions of said first plenum.

Claim 18

In an air cushion vehicle having a generally horizontal rigid deck with a front end and a rear end, or the like; the combination comprising; means defining a first plenum under the deck for maintaining an air cushion under the deck to lift the vehicle, means defining a second plenum below the deck generally at the front portion of the vehicle for lifting the vehicle, means for introducing air to the second plenum, and means defining a discharge port having a variable area for discharging air from said second plenum into said first plenum to supply said first plenum with air, said means defining said discharge port including a partition member extending continuously transversely of the vehicle to opposite sides of the vehicle generally at but above the bottom of the vehicle and the surface of travel and located forwardly of the center of the lifting area of the vehicle such that when the front end of said deck moves downwardly towards the surface of travel about the center of the lifting area of the vehicle said partition member will move closer to the surface of travel to reduce the area of said port and thereby increase the pressure in said second plenum for raising the deck and vehicle to thereby provide longitudinal pItch stability to the vehicle.

Claim 19

In an air cushion vehicle having a generally horizontal rigid deck with a front end and a rear end, or the like; the combination comprising; means defining a first plenum under the deck for maintaining an air cushion under the deck to lift the vehicle, means defining a second plenum below the deck generally at the front portion of the vehicle for lifting the vehicle, means for introducing air to the second plenum, and means defining a discharge port having a variable area for discharging air from said second plenum into said first plenum to supply said first plenum with air, said means defining said discharge port including a partition member extending continuously transversely of the vehicle to opposite sides of the vehicle generally at but above the bottom of the vehicle and the surface of travel and located forwardly of the center of the lifting area of the vehicle such that when the front end of said deck moves downwardly towards the surface of travel about the center of the lifting area of the vehicle said partition member will move closer to the surface of travel to reduce the area of said port and thereby increase the pressure in said second plenum for raising the deck and vehicle to thereby provide longitudinal pItch stability to the vehicle.

Claim 20

The air cushion vehicle defined in claim 15 further including a longitudinally extending partition depending from the deck in the second plenum generally at the longitudinal center line of the vehicle to provide roll stability for the vehicle.

Claim 21

In an air cushion vehicle having a generally horizontal deck or the like; the combination comprising means defining air conduits extending partly along opposite sides of the vehicle and a plenum chamber communicating with said air conduits to be supplied with air for lifting the vehicle, said means including opposite side skirt portions depending from opposite sides of the deck downwardly from the deck and under the deck, said side skirt portions having upper surfaces defining in part said air conduits and lower surfaces defining in part said plenum, said means further including a partition member extending transversely under the deck between the opposite side skirt portions and having a lower surface partly defining said plenum, said partition terminating at a forward end below said deck to define therewith a port for communicating said conduits with said plenum.

Claim 22

In an air cushion vehicle having a generally horizontal deck or the like; the combination comprising means defining air conduits extending partly along opposite sides of the vehicle and a plenum chamber communicating with said air conduits to be supplied with air for lifting the vehicle, said means including opposite side skirt portions depending from opposite sides of the deck downwardly from the deck and under the deck, said side skirt portions having upper surfaces defining in part said air conduits and lower surfaces defining in part said plenum, said means further including a partition member extending transversely under the deck between the opposite side skirt portions and having a lower surface partly defining said plenum, said partition terminating at a forward end below said deck to define therewith a port for communicating said conduits with said plenum.

Claim 23

An air cushion vehicle comprising in combination, a generally horizontally extending deck, inflatable skirt members depending from the deck and under the vehicle to include inflatable spaces while at the same time to define a plenum chamber below the surfaces of said skirt members for lifting the vehicle, air supply means for supplying air into said inflatable spaces to inflate said skirt members, and duct means communicating said inflatable spaces with said plenum to supply air into said plenum for lifting the vehicle, said skirt members including a rear skirt member attached to the rear end of the deck and extending outwardly and under the vehicle and upwardly and forwardly in curved configuration, side skirt members attached to opposite side portions of the deck and extending outwardly and under the vehicle then upwardly and being secured to opposite side portions of said rear skirt member, said air supply means communicating with the inflatable space enclosed by said rear skirt member, and said rear skirt member converging with said side skirt members toward the deck of the vehicle such that air entering into the space enclosed by the rear skirt member moves transversely at the rear of the vehicle and then forwardly along the sides of the vehicle.

Claim 24

An air cushion vehicle comprising in combination, a generally horizontally extending deck, inflatable skirt members depending from the deck and under the vehicle to include inflatable spaces while at the same time to define a plenum chamber below the surfaces of said skirt members for lifting the vehicle, air supply means for supplying air into said inflatable spaces to inflate said skirt members, and duct means communicating said inflatable spaces with said plenum to supply air into said plenum for lifting the vehicle, said skirt members including a rear skirt member attached to the rear end of the deck and extending outwardly and under the vehicle and upwardly and forwardly in curved configuration, side skirt members attached to opposite side portions of the deck and extending outwardly and under the vehicle then upwardly and being secured to opposite side portions of said rear skirt member, said air supply means communicating with the inflatable space enclosed by said rear skirt member, and said rear skirt member converging with said side skirt members toward the deck of the vehicle such that air entering into the space enclosed by the rear skirt member moves transversely at the rear of the vehicle and then forwardly along the sides of the vehicle.

Claim 25

In an air cushion vehicle including a generally horizontal deck or the like; the combination comprising means defining a first plenum below the deck for lifting the vehicle including flexible inflatable first skirt portions on opposite sides of the deck, means connecting said first skirt portions with respect to the deck such that upon inflation sections of said first skirt portions will extend in a direction outwardly of the vehicle in an arcuate shape, second skirt portions of flexible material joining said first skirt portions adjacent the bottoms of said first skirt portions to expend downwardly from said first skirt portions and longitudinally along the bottoms of said first skirt portions when the latter are inflated, said first and second skirt portions including a plurality of stiffener members located at spaced intervals along said first and second skirt portions to maintain said second skirt portions in generally vertical disposition below said first skirt portions when said first skirt portions are inflated while permitting said second skirt portions to be flexible in the region between the stiffener members, said stiffener members each including a first arm joined to said first skirt portion and a second arm extending at an angle to said first arm and joined to said second skirt portion and extending generally vertically thereof, said second skirt portions being shallow in depth relative to said first skirt portions, and said second skirt portions being made from relatively thin sheet material having a narrow bottom edge and the surface of travel.

Claim 26

In an air cushion vehicle including a generally horizontal deck or the like; the combination comprising means defining a first plenum below the deck for lifting the vehicle including flexible inflatable first skirt portions on opposite sides of the deck, means connecting said first skirt portions with respect to the deck such that upon inflation sections of said first skirt portions will extend in a direction outwardly of the vehicle in an arcuate shape, second skirt portions of flexible material joining said first skirt portions adjacent the bottoms of said first skirt portions to expend downwardly from said first skirt portions and longitudinally along the bottoms of said first skirt portions when the latter are inflated, said first and second skirt portions including a plurality of stiffener members located at spaced intervals along said first and second skirt portions to maintain said second skirt portions in generally vertical disposition below said first skirt portions when said first skirt portions are inflated while permitting said second skirt portions to be flexible in the region between the stiffener members, said stiffener members each including a first arm joined to said first skirt portion and a second arm extending at an angle to said first arm and joined to said second skirt portion and extending generally vertically thereof, said second skirt portions being shallow in depth relative to said first skirt portions, and said second skirt portions being made from relatively thin sheet material having a narrow bottom edge and the surface of travel.

Claim 27

In an air cushion vehicle including a generally horizontal deck or the like; the combination comprising means defining a first plenum below the deck for lifting the vehicle including flexible inflatable first skirt portions on opposite sides of the deck, means connecting said first skirt portions with respect to the deck such that upon inflation sections of said first skirt portions will extend in a direction outwardly of the vehicle in an arcuate shape, second skirt portions of flexible material joining said first skirt portions adjacent the bottoms of said first skirt portions to extend downwardly from said first skirt portions and longitudinally along the bottoms of said first skirt portions when the latter are inflated, said first and second skirt portions including a plurality of stiffener members located at spaced intervals along said first and second skirt portions to maintain said second skirt portions in generally vertical disposition below said first skirt portions when said first skirt portions are inflated while permitting said second skirt portions to be flexible in the region between the stiffener members said stiffener members each including a first arm joined to said first skirt portion and a second arm extending at an angle to said first arm and joined to said second skirt portion and extending generally vertically thereof, said second skirt portions being shallow in depth relative to said first skirt portions, said first skirt portions containing sufficient air pressure producing a moment on said first stiffener arm about a fulcrum located at the common juncture of said stiffener arms which moment maintains the second skirt portions downwardly in desired position.

Claim 28

In an air cushion vehicle including a generally horizontal deck or the like; the combination comprising means defining a first plenum below the deck for lifting the vehicle including flexible inflatable first skirt portions on opposite sides of the deck, means connecting said first skirt portions with respect to the deck such that upon inflation sections of said first skirt portions will extend in a direction outwardly of the vehicle in an arcuate shape, second skirt portions of flexible material joining said first skirt portions adjacent the bottoms of said first skirt portions to extend downwardly from said first skirt portions and longitudinally along the bottoms of said first skirt portions when the latter are inflated, said first and second skirt portions including a plurality of stiffener members located at spaced intervals along said first and second skirt portions to maintain said second skirt portions in generally vertical disposition below said first skirt portions when said first skirt portions are inflated while permitting said second skirt portions to be flexible in the region between the stiffener members said stiffener members each including a first arm joined to said first skirt portion and a second arm extending at an angle to said first arm and joined to said second skirt portion and extending generally vertically thereof, said second skirt portions being shallow in depth relative to said first skirt portions, said first skirt portions containing sufficient air pressure producing a moment on said first stiffener arm about a fulcrum located at the common juncture of said stiffener arms which moment maintains the second skirt portions downwardly in desired position.