A boat hull with a pivotally mounted hydrodynamic appendage

摘要

A boat hull with port and starboard side walls that are vertical in cross section whilst the bottom of the hull immediately prior to the commencement of the stern part there-after is horizontal in cross section. Extending throughout the buoyant hulls stern part a longitudinally rectangular flat plate with port and starboard upwardly extending side walls, one each side, are located throughout the length of the vessels stern part. An upwardly directed second rectangular flat plate is arranged fore/aft extends midway between the afore-said side walls to a height in excess of the said side walls. This upstanding plate butts its lowermost edge onto the mid-line of the first said plate. Linking the forward edge of the said longitudinally rectangular plate to the buoyant hull at its aftmost and deepest point are hinges. Thereby allowing an aftwardly upward pivotal movement of the said combined plate, whilst the afore-said upwardly extending fin of the said combination plate to locate within an aftwardly open slot casing that is additionally open upwardly and downwardly, into which the said combination plate moveably but securely fits. Means with which to raise/lower the combination plate are provided. Single or multiple combination plates, as described, operate independently or together.