Abstract: A sit-on-top kayak hull having an elevated void in the area between the normal seated position of a paddlers legs. The elevated void which is formed into the hull of the watercraft and extends there-through to a height above the normal laden waterline generally to a level of the approximate height of the gunwales forms a hole in the craft which is surrounded by walls. Various modules may be inserted into the hull void for varying needs, such as storage modules, clear modules for underwater vision, or flotation modules. The hull void additionally allows for changes in the running surface of the kayak by insertion of rudders, skegs, centerboards or other devices The void may be left open in full or part for egress of scuba hoses, anchors or other marine devices without affecting the structural integrity of the kayak, its buoyancy, or adversely affecting its performance.

Abstract: A multi-part kayak whereby the kayak body portion is a hollow perimeter void of a center where a traditional sit-on-top kayak cockpit area would reside. The kayak body is designed to accommodate multiple cockpit configurations via insertion into the void cockpit area. Additionally such arrangement provides removable cockpit central hulls to be affixed in a manner whereby no mechanical fasteners or points of possible water intrusion exist below the waterline. Means are provided so as to prevent occupants weight from forcing the removable cockpit central hull downward through the kayak body and from wave action forcing the removable cockpit central hull upward through the kayak body. One kayak body can accommodate multiple configurations of removable cockpit central hulls thereby eliminating the need for various kayaks to perform various functions.

Abstract: A combination canoe/kayak hull unitarily formed from seamless transparent thermoplastic where said thermoplastic is transparent polycarbonate or polycarbonate-acrylic blend. The canoe/kayak hull is molded in a fashion providing for multiple kayak top cap arrangements or canoe gunnel attachments dependent upon the trimming angle of the formed hull. The peripheral edge of the untrimmed hull is formed 90 degrees to the hull sides allowing for multiple trimming heights so as to be used as either a canoe or kayak hull. When hull is trimmed as a kayak, the trim line is on a horizontal plane following the lower edge of the canoe splash guard resulting in the peripheral edge being approximately 90 degrees to the bottom of the hull. When hull is trimmed as a canoe, the trim line is an arc where the ends of the hull are substantially taller than the midship peripheral edge.