A catamaran with a caterpillar track on the underside of each hull.
When afloat, the tracks are covered by "bomb-bay" sideways opening doors for streamlining; the doors are not watertight. The mass of the track mechanism replaces the ballast normally required in hulls.
On approaching shore, the
covers hinge up, fully exposing the tracks. As the speed should be low, turbulence and drag should not be excessive.
On contacting the shore, power to the tracks is engaged and the boat can be driven onto land and steered like any other tracked vehicle.
The track mechanisms are fabricated from stainless steel and other corrosion-resistant materials.
A design for an EkranoCaterpillarmaranPlan is being studied.