Buoyant structure

Abstract

A buoyant structure having a hull, a main deck, an upper cylindrical side section extending downwardly from the main deck, an upper frustoconical side section, a cylindrical neck, a lower ellipsoidal section that extends from the cylindrical neck, an ellipsoidal keel and a fin-shaped appendage secured to a lower and an outer portion of the exterior of the ellipsoid keel. The upper frustoconical side section located below the upper cylindrical side section and maintained to be above a water line for a transport depth and partially below the water line for an operational depth of the buoyant structure.

What is claimed is: 
     
         1 . A buoyant structure comprising: a hull having a main deck, an upper cylindrical side section, an upper frustoconical side section, a cylindrical neck, a lower frustoconical side section that extends from the cylindrical neck, a lower ellipsoidal section, an ellipsoid keel, and a fin-shaped appendage secured to a lower and an outer portion of the exterior of the ellipsoid keel. 
     
     
         2 . The buoyant structure of  claim 1 , wherein a pendulum is positioned to move between a transport depth and an operational depth, and wherein the pendulum is configured to dampen movement of a watercraft as the watercraft moves from side to side in water. 
     
     
         3 . The buoyant structure of  claim 1 , wherein the main deck has a superstructure comprising at least one member selected from the group consisting of: crew accommodations, a heliport, a crane, a control tower, a dynamic position system in the control tower, and an aircraft hangar. 
     
     
         4 . The buoyant structure of  claim 1 , wherein the hull has a berthing facility and catenary mooring lines for mooring the buoyant structure to a seafloor. 
     
     
         5 . The buoyant structure of  claim 1 , further comprising a gangway for traversing between the buoyant structure and a watercraft. 
     
     
         6 . The buoyant structure of  claim 1 , comprising the hull with a center of gravity below a center of buoyancy to provide an inherent stability to the buoyant structure. 
     
     
         7 . The buoyant structure of  claim 1 , wherein the upper frustoconical side section engages the cylindrical neck, wherein the buoyant structure comprises:
 a. the upper cylindrical side section extending downwardly from the main deck; and   b. the upper frustoconical side section located below the upper cylindrical side section and maintained to be above a water line for a transport depth and partially below a water line for an operational depth of the buoyant structure; and   
       wherein the upper frustoconical side section has a gradually reducing diameter from a diameter of the upper cylindrical side section.