Kinetic energy cavity penetrator weapon

Abstract

A method to increase the penetration of kinetic energy penetrating weapons designed to engage hardened and hardened deeply buried targets. The concept utilizes a projecting nose pin on the front of the penetrator to establish a terradynamic cavity similar to hydrodynamic cavities generated when certain projectiles penetrate water at velocities sufficient to penetrate in a supercavitation mode. The creation of a terradynamic cavity in which only the nose pin is in contact with the material being penetrated significantly reduces the drag of the penetrator enabling it to penetrate deeper into various media than other more conventional designs. The invention uses two modes of penetration. A guided mode is employed where the penetrator, with its projecting nose pin, normally would be unstable and is maintained stable in a straight-line trajectory utilizing an inverse, angle-angle rate guidance law and jet reaction control system. The guided mode also can be used on a normally unstable penetrator penetrating in a cavity penetration mode to change the trajectory and guide the penetrator on a predetermined path using best remaining path guidance concepts. An unguided penetrator mode utilizes a standoff pin which reduces the drag but is tailored so that the penetrator, in the penetration process, is normally stable and penetrates in a straight-line.

I claim:  
     
         1 . In a terradynamic penetrator having an elongated body, the improvement comprising: 
 a nose pin attached to the elongated body at a first end, said nose pin sized relative to a size of the elongated body to create a terradynamic cavity in a target through which said body passes substantially entirely within said cavity.    
     
     
         2 . The terradynamic penetrator in accordance with  claim 1 , in which said nose pin is of stepped configuration.  
     
     
         3 . The terradynamic penetrator in accordance with  claim 1 , in which a diameter of said nose pin relative to a diameter of said body is in a range of 1 to 3.5 or less.  
     
     
         4 - 11 . (Canceled)  
     
     
         12 . The terradynamic penetrator in accordance with  claim 1 , in which said nose pin is flat-faced.  
     
     
         13 . The terradynamic penetrator in accordance with  claim 1 , in which said nose pin includes a forwardly-facing surface of any of round, conical, ogival and spherical configuration.  
     
     
         14 . The terradynamic penetrator in accordance with  claim 1 , in which said nose pin is of tapered configuration.  
     
     
         15 . (Canceled)  
     
     
         16 . The terradynamic penetrator in accordance with  claim 1 , including a delayed ignition system.  
     
     
         17 . The terradynamic penetrator in accordance with  claim 3 , wherein the diameter of said nose pin relative to the diameter of said body is less than 1 to 2.5.  
     
     
         18 . The terradynamic penetrator in accordance with  claim 17 , wherein the diameter of said nose pin relative to the diameter of said body is about 2.5.  
     
     
         19 . A penetrator comprising: 
 an elongated body; and    a nose cap on a first end of the elongated body,    wherein the elongated body has an outer surface having a first diameter, wherein the nose cap has an outer surface having a second diameter, and wherein a ratio of the first diameter to the second diameter is in a range of 3.5:1 to 1:1.    
     
     
         20 . The penetrator of  claim 19 , wherein the ratio is about 2.5:1.  
     
     
         21 . The penetrator of  claim 19 , wherein said nose cap is of stepped configuration having a first stepped diameter at a distal end from the elongated body and a second stepped diameter at a proximal end toward the elongated body, the first stepped diameter less than the second stepped diameter.  
     
     
         22 . The penetrator of  claim 19 , wherein the ratio is from 2.5:1 to 1:1.  
     
     
         23 . The penetrator of  claim 22 , wherein the ratio is about 1:2.5.  
     
     
         24 . The penetrator of  claim 19 , wherein the nose cap includes a forwardly-facing surface at a distal end from the elongated body, the forwardly-facing surface have a shape selected from the group consisting of round, conical, ogival and spherical.  
     
     
         25 . The penetrator of  claim 19 , wherein the nose cap is of tapered from a base at a proximal end toward the elongated body to a distal end from the elongated body.  
     
     
         26 . The penetrator of  claim 19 , comprising a stabilizer.  
     
     
         27 . The penetrator of  claim 26 , wherein the stabilizer employs an angle-angle rate inverse guidance law.  
     
     
         28 . The penetrator of  claim 26 , wherein the stabilizer includes a jet reaction control system.