Patent ID: 7290496

Claim:
An unmanned autonomous submarine, comprising: a hull formed by at least two hull sections and defining an interior cabin therein, said cabin adapted to retain pressurized air; a plurality of fasteners affixed to said hull sections and adapted for joining said at least two hull sections, said plurality of fasteners being one of internally and externally affixed to opposing connecting ends of said hull sections; a plurality of hydrofoils attached to opposed external side surfaces of said hull sections for providing stability and maneuverability of said hull; a propulsion system for providing propelling force to said hull; and a ballast system for raising and submersing said hull, said ballast system comprising: a ballast tank adapted to receive a predetermined level of water externally from the submarine and a predetermined amount of the pressurized air from said cabin; and a compressor coupled to said ballast tank to form a closed loop system, said compressor adapted to force air into said cabin from said ballast tank to increase the water level in the tank and thereby cause said hull to submerge, and said compressor being adapted to force air into said ballast tank from said cabin to decrease the water level in the tank and thereby cause the submarine to ascend.