Closed tunnel system for outboard jet motors

Abstract

Described is a hull with a transom for supporting an outboard jet motor; a tunnel disposed in a bottom surface of the hull and extending to the transom; an adapter disposed where the transom and the tunnel meet, the adapter comprising a shrouded opening for communication with the outboard jet motor at an intake of the outboard jet motor; wherein the tunnel is configured for directing a flow of water through the tunnel, into the adapter, and into the intake of the outboard jet motor. Also described is a directional device which receives the jet output of the outboard jet motor and provides a capability for making vertical or horizontal adjustments to the jet output or reversing the jet output, and a boat which includes the boat hull and directional device.

1 . A boat hull comprising:
 a transom for supporting an outboard jet motor;   a tunnel disposed in a bottom surface of the hull and extending to the transom; and   an adapter disposed where the transom and the tunnel meet, the adapter comprising a shrouded opening for communication with the outboard jet motor at an intake of the outboard jet motor;   wherein the tunnel is configured for directing a flow of water through the tunnel, into the adapter, and into the intake of the outboard jet motor; and   wherein the adapter is configured to provide the outboard jet motor intake disposed at an angle that slopes upwardly toward the tunnel.   
     
     
         2 . The boat hull of  claim 1 , wherein the tunnel comprises a front end that merges with a bottom surface of the hull and a back end that terminates at the transom. 
     
     
         3 . The boat hull of  claim 2 , wherein the tunnel slopes upwardly at an angle from the front end of the tunnel to the back end of the tunnel. 
     
     
         4 . The boat hull of  claim 2 , wherein the tunnel slopes upwardly from the front end of the tunnel to the back end of the tunnel at an angle between about 5 degrees and about 45 degrees. 
     
     
         5 . The boat hull of  claim 4 , wherein the depth of the tunnel increases from the front end of the tunnel to the back end of the tunnel. 
     
     
         6 . The boat hull of  claim 4 , wherein the tunnel has a width that is wider at the front end of the tunnel than at the back end of the tunnel. 
     
     
         7 . The boat hull of  claim 1 , wherein the tunnel is disposed on a centerline along the bottom surface of the hull. 
     
     
         8 . The boat hull of  claim 1 , wherein the hull is a modified V hull. 
     
     
         9 . The boat hull of  claim 1 , wherein the adapter comprises a plate in communication with the shrouded opening and the shrouded opening is disposed at an angle relative to the plate. 
     
     
         10 . The boat hull of  claim 1 , wherein the intake of the outboard jet motor is disposed in communication with the shrouded opening. 
     
     
         11 . A boat hull comprising:
 a transom for supporting an outboard jet motor;   a tunnel disposed in a bottom surface of the hull, the tunnel sloping upwardly at an angle toward the transom; and   an adapter comprising a shrouded opening for communication with an intake of the outboard jet motor, wherein the adapter is configured to provide the intake of the outboard jet motor at an angle that slopes upwardly toward the tunnel;   wherein the tunnel is configured for directing a flow of water through the tunnel, into the adapter, and into the intake of the outboard jet motor.   
     
     
         12 . The boat hull of  claim 11 , wherein the tunnel slopes upwardly from the front end of the tunnel to the back end of the tunnel at an acute angle. 
     
     
         13 . The boat hull of  claim 11 , wherein the tunnel has a width that is wider at the front end of the tunnel than at the back end of the tunnel. 
     
     
         14 . The boat hull of  claim 11 , wherein the tunnel is disposed on a centerline along the bottom surface of the hull. 
     
     
         15 . The boat hull of  claim 11 , wherein the tunnel shape is parabolic, U-shaped, trapezoidal, triangular, square, rectangular, pentagonal, hexagonal, or octagonal in shape. 
     
     
         16 . The boat hull of  claim 11 , wherein the tunnel walls are parallel to one another. 
     
     
         17 . The boat hull of  claim 11 , wherein the tunnel walls slope outwardly from the top of the tunnel to the bottom of the hull. 
     
     
         18 . A boat hull comprising:
 a modified V hull providing a tunnel in a bottom of the hull for flow of water;   a transom for supporting an outboard jet motor; and   an adapter disposed in a manner to provide a transition from the tunnel to the transom, the adapter comprising a shrouded opening for communication with the outboard jet motor at an intake of the outboard jet motor;   wherein the tunnel is configured for directing a flow of water through the tunnel, into the adapter, and into the intake of the outboard jet motor.   
     
     
         19 . The boat hull of  claim 18 , wherein the tunnel slopes upwardly from a front end of the tunnel to a back end of the tunnel. 
     
     
         20 . The boat hull of  claim 18 , wherein the tunnel comprises walls that slope outwardly from a top of the tunnel to the bottom of the hull.