To provide a gate rudder capable of reducing energy consumption during a voyage of a ship.

A gate rudder including a pair of rudders including a left rudder and a right rudder disposed left and right, respectively, of a propeller at a stern, wherein each of the rudders includes a first rudder portion extending in a horizontal direction and a second rudder portion linearly extending in a vertical direction in rear view, wherein a rudder chord length of the second rudder portion in a front-rear direction is 40 to 100% of a diameter of the propeller, wherein the propeller is provided within a range of 15 to 65% of the rudder chord length from a front edge of the second rudder portion in side view, and wherein a rudder shaft that drives each of the rudders is provided at a position within a range of 30 to 50% of the rudder chord length from the front edge of the second rudder portion in side view.

A boat includes a planing hull, a propeller, a main rudder, and a pair of flanking rudders. The planing hull has port and starboard sides, a transom, a hull bottom, and a centerline running down the middle of the boat, halfway between the port and starboard sides. The propeller is positioned forward of the transom and beneath the hull bottom. The main rudder is positioned aft of the propeller. The main rudder has a rotation axis about which the main rudder rotates. The flanking rudders are positioned forward of the propeller. One of the flanking rudders is positioned on the port side of the centerline, and the other flanking rudder is positioned on the starboard side of the centerline.

A rudder device for a hydrojet vessel. The rudder device includes a mounting plate, a primary rudder and a secondary rudder coupled to a hydrojet. The primary rudder and the secondary rudder providing steerage as the hydrojet vessel is displaced through the water.

Disclosed herein is an aquatic towable device comprising a body, a towline connector, a rudder fin, and a steering apparatus. The towline connector is placed at one end of the body and above a waterline of the body when the device is occupied by a passenger. The rudder fin is attached pivotably to an underside of the body and placed toward the towline connector and positioned so at least part of the rudder fin will be underwater when the device is occupied by a passenger. The steering apparatus is attached to the rudder fin that pivots the rudder fin and is accessible from a top side of the body.

A boat includes a planing hull, a propeller, a main rudder, and a pair of flanking rudders. The planing hull has port and starboard sides, a transom, a hull bottom, and a centerline running down the middle of the boat, halfway between the port and starboard sides. The propeller is positioned forward of the transom and beneath the hull bottom. The main rudder is positioned aft of the propeller. The main rudder has a rotation axis about which the main rudder rotates. The flanking rudders are positioned forward of the propeller. One of the flanking rudders is positioned on the port side of the centerline, and the other flanking rudder is positioned on the starboard side of the centerline.

A boat includes a planing hull, a propeller, a main rudder, and a pair of flanking rudders. The planing hull has port and starboard sides, a transom, a hull bottom, and a centerline running down the middle of the boat, halfway between the port and starboard sides. The propeller is positioned forward of the transom and beneath the hull bottom. The main rudder is positioned aft of the propeller. The main rudder has a rotation axis about which the main rudder rotates. The flanking rudders are positioned forward of the propeller. One of the flanking rudders is positioned on the port side of the centerline, and the other flanking rudder is positioned on the starboard side of the centerline.

A rudder device is disclosed for a hydrojet vessel. The rudder device comprises a first mounting bracket coupled to a first hydrojet. A first rudder is coupled to the first hydrojet and the first mounting bracket. A second mounting bracket is coupled to a second hydrojet. A second rudder is coupled to the second hydrojet and the second mounting bracket. A coupling rod is pivotably coupled to the first hydrojet, the second hydrojet and a hull rudder for pivoting in alignment and in unison the first rudder with the first hydrojet and the second rudder with the second hydrojet relative to the hull rudder. The first rudder and the second rudder provide steerage to the vessel during non directional thrust absent from the first hydrojet and the second hydrojet.

There is disclosed a dual rudder system and method of improving the maneuvering ability and versatility of marine vehicles in navigable waters. A dual rudder steering assembly may be utilized in conjunction with a propeller of a marine vehicle. Moreover, multiple dual rudder steering assemblies may be utilized in conjunction with multiple propellers. A system for retrofitting existing marine vehicles with the disclosed devices is also disclosed, as well as a method of retrofitting existing marine vehicles with the steering system. Therefore, the disclosed steering system is compatible with pre-existing steering controls.

A boat includes a planing hull, a propeller, a main rudder, and a pair of flanking rudders. The planing hull has port and starboard sides, a transom, a hull bottom, and a centerline running down the middle of the boat, halfway between the port and starboard sides. The propeller is positioned forward of the transom and beneath the hull bottom. The main rudder is positioned aft of the propeller. The main rudder has a rotation axis about which the main rudder rotates. The flanking rudders are positioned forward of the propeller. One of the flanking rudders is positioned on the port side of the centerline, and the other flanking rudder is positioned on the starboard side of the centerline.

There is disclosed a dual rudder system and method of improving the maneuvering ability and versatility of marine vehicles in navigable waters. A dual rudder steering assembly may be utilized in conjunction with a propeller of a marine vehicle. Moreover, multiple dual rudder steering assemblies may be utilized in conjunction with multiple propellers. A system for retrofitting existing marine vehicles with the disclosed devices is also disclosed, as well as a method of retrofitting existing marine vehicles with the steering system. Therefore, the disclosed steering system is compatible with pre-existing steering controls.