Air lubricated ship

Abstract

Presented is an air lubricated ship that offers improved efficiency and stability over the prior art. Features of the preferred embodiment of the invention include: 1) a submerged bow that is generally proximal in depth to the stern, 2) a hydrofoil at the bow that not only adds stability but also allows the pressurized air layer(s) to extend further forward under the hull thereby reducing wetted area friction, 3) use of more than one air layer in series which is generally accomplished by water deflecting steps at the air layers forward portions, 4) special positioning of propulsors so that they do not interfere with the air layer(s) by aspirating pressurized air from the air layer(s), 5) optional outrigger hulls to aid to stability and to also increase useful deck area, 6) optional configurations that allow for use of more than one air lubricated hull where such hulls are connected by structure in a catamaran type hull arrangement, and 7) Configurations of the preceding that do not utilize the hydrofoil.

What I claim is:  
     
         1 . In an improved air lubricated ship, the improvement comprising: 
 a first pressurized gas layer with a forward portion of said first pressurized gas layer disposed, at least in its majority, aft of a first step in an underside of said improved air lubricated ship when said improved air lubricated ship is moving forward and including a first artificial gas pressurization means to supply pressurized gas to said first pressurized gas layer and where said first pressurized gas layer, on average, slopes upward going from forward to aft and wherein a lowermost submerged portion proximal a bow of said improved air lubricated ship is within twenty percent of the submerged depth of a lowermost portion proximal of an aft portion of said improved air lubricated ship when the improved air lubricated ship is moving forward in a calm sea.    
     
     
         2 . The improved air lubricated ship of  claim 1  wherein a lowermost submerged portion proximal a bow of said improved air lubricated ship is within twenty-five percent of the submerged depth of a lowermost portion proximal of an aft portion of said improved air lubricated ship when the improved air lubricated ship is moving forward in a calm sea.  
     
     
         3 . The improved air lubricated ship of  claim 1  wherein a lowermost submerged portion proximal a bow of said improved air lubricated ship is within thirty percent of the submerged depth of a lowermost portion proximal of an aft portion of said improved air lubricated ship when the improved air lubricated ship is moving forward in a calm sea.  
     
     
         4 . The improved air lubricated ship of  claim 1  wherein said first step is disposed, at least in its majority, in a forward fifteen percent of a length of said improved air lubricated ship.  
     
     
         5 . The improved air lubricated ship of  claim 1  wherein said first step is disposed, at least in its majority, in a forward twenty percent of a length of said improved air lubricated ship.  
     
     
         6 . The improved air lubricated ship of  claim 1  wherein said first step is disposed, at least in its majority, in a forward twenty-five percent of a length of said improved air lubricated ship.  
     
     
         7 . The improved air lubricated ship of  claim 1  wherein said first step is disposed, at least in its majority, in a forward thirty percent of a length of said improved air lubricated ship.  
     
     
         8 . The improved air lubricated ship of  claim 1  wherein said first gas layer is bordered over at least a majority of its length by sidekeels.  
     
     
         9 . The improved air lubricated ship of  claim 8  which further comprises a second step in the underside of said air lubricated ship wherein said second step is disposed, at least in its majority, proximal an aft end of said first pressurized gas layer and wherein a second pressurized gas layer is disposed, at least in its majority, aft of said second step and where said second pressurized gas layer, on average, slopes upward going from forward to aft and is bordered over at least a majority of its length by said sidekeels.  
     
     
         10 . The improved air lubricated ship of  claim 9  which further comprises a third step in the underside of the air lubricated ship wherein said third step is disposed, at least in its majority, proximal an aft end of said second pressurized gas layer and where a third pressurized gas layer is disposed, at least in its majority, aft of said third step and wherein said third pressurized gas layer, on average, slopes upward going from forward to aft and is bordered over at least a majority of its length by said sidekeels.  
     
     
         11 . The improved air lubricated ship of  claim 9  wherein the second gas layer receives pressurized gas from the first artificial gas pressurization means.  
     
     
         12 . The improved air lubricated ship of  claim 9  wherein the second gas layer receives pressurized gas from a second artificial gas pressurization means.  
     
     
         13 . The improved air lubricated ship of  claim 10  wherein the third gas layer receives pressurized gas from an artificial gas pressurization means.  
     
     
         14 . The improved air lubricated ship of  claim 1  which further comprises a first downward extending gas restraining seal positioned proximal an aft end of said first pressurized gas layer.  
     
     
         15 . The improved air lubricated ship of  claim 1  wherein a lower surface proximal to and forward of said first step is turned downward to direct water flow downward when the improved air lubricated ship is moving forward.  
     
     
         16 . The improved air lubricated ship of  claim 1  wherein an underwater section of the improved air lubricated ship's hull, as seen in a horizontal plane taken below a waterline when the improved air lubricated ship is moving forward in a calm sea, is at least partially airfoil shaped over its forward portions.  
     
     
         17 . The improved air lubricated ship of  claim 1  wherein an underwater section of the improved air lubricated ship's bow is at least in part bulbous shaped.  
     
     
         18 . The improved air lubricated ship of  claim 14  wherein said first downward extending gas restraining seal, as seen in a vertical transverse plane of the improved air lubricated ship, is angled to horizontal over a majority of its width.  
     
     
         19 . The improved air lubricated ship of  claim 14  which further comprises a second downward extending gas restraining seal positioned proximal an aft end of said second gas layer.  
     
     
         20 . The improved air lubricated ship of  claim 19  wherein said second downward extending gas restraining seal, as seen in a vertical transverse plane of the improved air lubricated ship, is angled to horizontal over a majority of its width.  
     
     
         21 . The improved air lubricated ship of  claim 19  which further comprises a third downward extending gas restraining seal positioned proximal an aft end of said third gas layer.  
     
     
         22 . The improved air lubricated ship of  claim 21  wherein said third downward extending gas restraining seal, as seen in a vertical transverse plane of the improved air lubricated ship, is angled to horizontal over a majority of its width.  
     
     
         23 . The improved air lubricated ship of  claim 1  which further comprises outrigger hulls disposed either side of a main hull of said air lubricated ship.  
     
     
         24 . The improved air lubricated ship of  claim 23  wherein said outrigger hulls are retractable.  
     
     
         25 . The improved air lubricated ship of  claim 24  wherein said outrigger hulls are retractable downward such that a portion of at least one of the outrigger hulls is disposed below one of the sidekeels of said improved air lubricated ship.  
     
     
         26 . The improved air lubricated ship of  claim 1  wherein propulsors are disposed proximal an aft end of said sidekeels.  
     
     
         27 . The improved air lubricated ship of  claim 26  wherein said propulsors are waterjets that take in inlet water from a portion of a periphery of said sidekeels.  
     
     
         28 . The improved air lubricated ship of  claim 27  which further comprises one or more air fences disposed above and proximal to water inlets of said waterjets whereby said air fences restrict air from flowing downward into the waterjet's water inlets.  
     
     
         29 . The improved air lubricated ship of  claim 26  wherein said propulsors are propellers with said propellers rotating, as seen in an aft view of the improved air lubricated ship, with an upper blade rotating in an outboard direction to thereby aid in restricting gas leakage from an aft gas layer by building up a pressure front of water over an aft end of said aft gas layer.  
     
     
         30 . The improved air lubricated ship of  claim 26  wherein an external portion of the sidekeels proximal the propulsors is, at least in their majority, curvilinear.  
     
     
         31 . The improved air lubricated ship of  claim 1  wherein there are multiple air lubricated hulls in mechanical communication by means of a connecting structure.  
     
     
         32 . The improved air lubricated ship of  claim 1  wherein a bow, as seen in a profile view, is within five degrees of vertical over a majority of its height.  
     
     
         33 . The improved air lubricated ship of  claim 1  wherein a bow, as seen in a profile view, is within ten degrees of vertical over a majority of its height.  
     
     
         34 . The improved air lubricated ship of  claim 1  wherein a bow, as seen in a profile view, is within fifteen degrees of vertical over a majority of its height.  
     
     
         35 . The improved air lubricated ship of  claim 1  which further comprises a hydrofoil proximal its forward underwater portions.  
     
     
         36 . In an improved air lubricated ship, the improvement comprising: 
 a first pressurized gas layer with a forward portion of said first pressurized gas layer disposed, at least in its majority, aft of a first step in an underside of said improved air lubricated ship when said improved air lubricated ship is moving forward and including a first artificial gas pressurization means to supply pressurized gas to said first pressurized gas layer and where said first pressurized gas layer, on average, slopes upward going from forward to aft and wherein a bow of said improved air lubricated ship, as seen in a profile view, is within five degrees of vertical over a majority of its height.    
     
     
         37 . The improved air lubricated ship of  claim 36  wherein a bow, as seen in a profile view, is within ten degrees of vertical over a majority of its height.  
     
     
         38 . The improved air lubricated ship of  claim 1  wherein a bow, as seen in a profile view, is within fifteen degrees of vertical over a majority of its height.  
     
     
         39 . The improved air lubricated ship of  claim 1  which further comprises a hydrofoil proximal its forward underwater portions.  
     
     
         40 . The improved air lubricated ship of  claim 36  wherein a lowermost submerged portion proximal a bow of said improved air lubricated ship is within twenty percent of the submerged depth of a lowermost portion proximal of an aft portion of said improved air lubricated ship when the improved air lubricated ship is moving forward in a calm sea.  
     
     
         41 . The improved air lubricated ship of  claim 1  wherein a lowermost submerged portion proximal a bow of said improved air lubricated ship is within twenty-five percent of the submerged depth of a lowermost portion proximal of an aft portion of said improved air lubricated ship when the improved air lubricated ship is moving forward in a calm sea.  
     
     
         42 . In an improved air lubricated ship, the improvement comprising: 
 a first pressurized gas layer with a forward portion of said first pressurized gas layer disposed, at least in its majority, aft of a first step in an underside of said improved air lubricated ship when said improved air lubricated ship is moving forward and including a first artificial gas pressurization means to supply pressurized gas to said first pressurized gas layer and where said first pressurized gas layer, on average, slopes upward going from forward to aft and wherein an underwater section of the improved air lubricated ship's hull, as seen in a horizontal plane taken below a waterline when the improved air lubricated ship is moving forward in a calm sea, is at least partially airfoil shaped over its forward portions.    
     
     
         43 . The improved air lubricated ship of  claim 42  wherein a bow of said improved air lubricated ship, as seen in a profile view, is within five degrees of vertical over a majority of its height.  
     
     
         44 . The improved air lubricated ship of  claim 42  wherein a bow of said improved air lubricated ship, as seen in a profile view, is within ten degrees of vertical over a majority of its height.  
     
     
         45 . The improved air lubricated ship of  claim 42  wherein a bow of said improved air lubricated ship, as seen in a profile view, is within fifteen degrees of vertical over a majority of its height.