Swap type floating platforms

A ship water plane area protected, tied, anchored, floating platform comprising:

• a platform upper deck;
• and
• at least three struts, each of said at least three three struts further comprising,
• a vertical hollow column having a bottom end open to surrounding water and having an upper end connected to said platform upper deck;
• a downward extension of said vertical hollow column which has a flange on an upper end which is connected to said vertical hollow column;
• a buoyancy vessel inserted into said vertical hollow column having a lower end closed and an upper end open;
• and
• a ring connecting said upper end of said buoyancy vessel to said upper end of said vertical hollow column;
• a conduit located below water level connecting a space between said vertical hollow columns and the respective buoyancy vessel of each said strut to a similar space in each other said strut;
• means for generating vertical forces, acting on said ring, located between each of said buoyancy vessels and each of said vertical hollow columns, to control the trim and list of the platform;
• a foundation on the bottom of the sea including a pontoon with ballasts, an anchoring means and a well template;
• and
• catenary mooring lines from the platform to said anchoring means of said foundation.

A ship water plane area protected type catamaran comprising:

• a propulsion system;
• at least two submerged hulls, each of said submerged hulls comprising at least two struts interconnecting said upper deck with said submerged hull;
• each of said struts comprising a vertical hollow column having the form of an elongated box shaped to reduce drag and having its bottom at least partially open to the surrounding water;
• a buoyancy vessel inserted into said hollow column having a form of an elongated box, a lower end which is closed and an upper end open to the atmosphere and a cover plate connecting said upper end of said buoyancy vessel to an upper end of said hollow column;
• cross-conduits located below water level and having a form of an elongated box shaped to reduce drag, interconnecting said hollow columns and said inserted buoyancy vessels of oppositely located struts;
• longitudinal conduits located below water level and passing through said submerged hull interconnecting said hollow columns and said inserted buoyancy vessels of said struts located along one of said submerged hulls;
• and
• means for generating vertical forces acting on said cover plate located between said buoyancy vessel and said vertical hollow column to control list and trim of said catamaran.

A ship water area protected single body ship comprising:

• an outer hull, including sidewalls;
• an inner hull, comprising at least two water-level equalizing conduits crossing said inner hull at said inner hull's lowest part;
• an upper deck;
• at least two partitions dividing a space between said outer hull and said inner hull into sections, said sections being connected to each other through openings in lower portions of said partitions;
• means for generating vertical forces, acting on said upper deck in an area covering said space between said inner hull and said outer hull, thereby controlling trim and list of the single body ship.