Watercraft

Abstract

There is described a watercraft ( 1 ), comprising a hull ( 6 ) pivotally mounted for rotation about a longitudinal axis ( 10 ) relative to a float assembly ( 2, 3 ) having only two stable floating positions. The float assembly may comprise two spaced floats extending longitudinally of the watercraft and joined by transverse spars ( 4, 5 ), the hull being mounted between the transverse spars. Alternatively, the watercraft may comprise a first float assembly ( 27 ) mounted to a forward end of the hull and a second float assembly ( 33 ) mounted to an aft end of the hull, each float assembly comprising a pair of floats ( 28, 29; 35, 36 ) spaced transversely from the longitudinal axis of rotation of the hull.

1 . A watercraft, comprising a hull pivotally mounted for rotation about a longitudinal axis relative to a float assembly, wherein the float assembly has only two stable floating positions angularly separated by 180 degrees about a longitudinal axis of the watercraft. 
     
     
         2 . A watercraft according to  claim 1 , wherein the watercraft comprises a first float assembly mounted to a forward end of the hull and a second float assembly mounted to an aft end of the hull. 
     
     
         3 . A watercraft according to  claim 2 , wherein the first and second float assemblies each comprise spaced floats extending longitudinally of the watercraft and symmetrically spaced transversely from the longitudinal axis, the floats being joined by a transverse spar, the hull being mounted between the transverse spars of the first and second float assemblies. 
     
     
         4 . A watercraft according to  claim 2 , wherein the first and second float assemblies each comprise two floats. 
     
     
         5 . A watercraft according to  claim 2 , wherein the first and second float assemblies each comprise four floats arranged side-by side along a spar. 
     
     
         6 . A watercraft according to  claim 2 , wherein the first and second float assemblies each comprise a single float having orthogonal axes of symmetry intersecting on the longitudinal axis of rotation of the watercraft. 
     
     
         7 . A watercraft according to  claim 1 , wherein the float assembly comprises a pair of spaced floats extending longitudinally of the watercraft and joined by two transverse spars, the hull being mounted to the transverse spars for rotation about the longitudinal axis. 
     
     
         8 . A watercraft according to  claim 1 , wherein the hull comprises propulsion means extending from the hull and adapted to be immersed when the craft is afloat. 
     
     
         9 . A watercraft according to  claim 8 , wherein the propulsion means comprises a propeller. 
     
     
         10 . A watercraft according to  claim 8 , wherein the propulsion means comprises a water jet. 
     
     
         11 . A watercraft according to  claim 2 , further including means to selectively resist or prevent relative rotation between the hull and the float assemblies. 
     
     
         12 . A watercraft according to  claim 2 , wherein the hull and the float assemblies may be selectively locked in one or more relative angular positions. 
     
     
         13 . A watercraft according  claim 2 , further including sensor means to detect the orientation of the hull relative to the vertical, actuator means to rotate the hull relative to one or more of the float assemblies, and control means responsive to an output of the sensor means and operable to drive the actuator means to maintain the hull in a desired orientation relative to the vertical. 
     
     
         14 . (canceled)