Abstract: A self-propelled ski is powered by an engine connected to a pair of treads disposed on opposite lateral sides of the ski. The treads are mounted on a chassis which is pivotally connected to the ski and can be moved between an operative position with the treads engaging the ground surface and an inoperative position with the treads disposed above the surface.

Abstract: An improved ski device which incorporates a power unit for providing forward thrust and which is capable of operation over water, snow, ice, artificial surfaces, or the like. In one embodiment, the unit utilizes an upright chassis which is articulated to a single runner and has a seat with handles that preferably include control and brake means. The power unit may be mounted in the chassis or rearwardly of the seat on a framework. The framework may be made adjustable so as to permit the angle of thrust imparted by the power unit to be varied. In an alternative embodiment, steering means may be provided in the form of a separate, steering ski pivotally mounted to a steering column and handle bar assembly which extends from the forward portion of the chassis. Outrigger pontoons or skis may be provided as the intended use dictates.

Abstract: A new and improved ski device capable of operation over water, snow, ice, artificial surfaces, or the like. The unit utilizes a seat design articulated to a single runner in a fashion analogous to the spacing of foot bindings in an ordinary ski. The unit features a stremlined chassis, an anti-sway linkage, improved shock-absorbing means, and a pair of auxiliary foot-mountable short skis for stability, control, and added performance.