Abstract: A baffled muzzle brake and seal system for submerged gun operation includes a muzzle brake chamber mounted to the muzzle of a submerged gun barrel. A baffle assembly mounted within the chamber deflects the propellant gasses produced by operation of the gun and sabot fragments into an annular cher surrounding the baffle assembly while allowing passage of a projectile through the assembly. A valve seal in the muzzle end of the muzzle brake chamber cycles between a fully open condition, to allow passage of the projectile, and a fully closed position, to seal the muzzle brake chamber against the entry of water. At least one pressurized air input allows the muzzle brake chamber to be pressurized when the seal is not in the fully closed position, thereby preventing entry of water. A gas exhaust provides a means for removing propellant gasses from the chamber.

Abstract: The present invention relates to an underwater weapon having a barrel with n opening through which a projectile is discharged. The weapon further has an apparatus for pressurizing the interior of the barrel to a pressure greater than the ambient pressure to keep water from entering the gun barrel at any point around the circumference of the muzzle opening. The pressurizing apparatus includes a source of gas, a pressure regulator for adjusting the flow of the gas and the pressure within the barrel, and a distribution network for distributing the gas near the muzzle opening and at an end of the barrel remote from the muzzle opening.

Abstract: A sealing apparatus which may be mounted on multi or single barreled guns disclosed to provide a watertight seal on an underwater gun. The sealing apparatus comprises a sealing plate connected to a gun barrel and a muzzle seal which fit on the muzzle of the gun barrel and frictionally engages the sealing plate. The sealing plate includes a firing aperture which aligns with the gun barrel when the gun is fired.

Abstract: The present invention relates to an underwater weapon having a system for aling the opening of a gun barrel to prevent the ingress of water. The sealing system includes a non-metallic or metallic tape for covering and sealing the opening and a mating surface on the gun barrel against which the tape is seated to prevent the ingress of water. The sealing system further includes sprockets for advancing the tape across the opening of the gun barrel and for maintaining the tape in a taut position during operation.

Abstract: In a fluid such as water the direction of a vessel is controlled by a fin ving at least one fixed chordwise segment and at least one cantilever mounted movable segment secured to the fixed segment by a backbone or spine spring at the neutral axis, and by differently tensioned control wires that are used to achieve camber variations under the influence of the vessel's control system. An elastomeric skin is supported on stiffeners to maintain the general fin cross section during such camber changes.