Patent 8069808 was granted and assigned to Alaska Native Technologies, LLC on December, 2011 by the United States Patent and Trademark Office.
A buoyancy control system comprises a housing and first and second pistons movably supported by the housing. In a shallow mode, displacement of the first piston alters a buoyancy of the buoyancy control system. In a deep mode, displacement of the first and second pistons alters the buoyancy of the buoyancy control system.