Abstract: An amphibious vehicle, normally an automobile, has a centrally located displacement hull body portion, containing a passenger compartment and an engine, that is of excellent hydrodynamic profile similar to a canoe. Wheels located at the end of four-wheel-drive axle half-shafts in, preferably, a DeDion suspension are located entirely outboard of the displacement hull. The wheels are conventionally suspended in their lowered positions on land, and are raised by actuators on water. Moveable skis first move on a pantograph linkage from first locations upwards and to the rear of the front wheels into second, forward, locations where the ski tips slide under the raised front wheels, deflecting water under the front wheels and generally improving vehicle hydrodynamics in the manner of outriggers. With increasing speed of the vehicle through the water, the skis are moved aft and downward on the pantograph linkage to lowered third locations.

Abstract: Hydrofoil watercraft (HFWC)--particularly including extended-performance hydrofoil watercraft (E-P HFWC) characterized by a submerged demi-hull mounting hydrofoils, and also high-performance personal hydrofoil watercraft (P HFWC)--are rendered both tractable and pleasant to operate throughout broad operational ranges by the provision of selective upwards (i) flotation and (ii) planing forces from two sponsons moveable in position at the ends of hinged arms. At their maximally elevated, inboard, positions the sponsons are integrated with the contours of the main displacement hull--preferably a "V"-shape hull--so as to permit the HFWC to operate efficiently and handle well while not on plane, including while cutting through heavy seas.