Abstract: A rotating thrust-producing apparatus having a control system includes a rotatable foil having opposite first and second faces and a plurality of spaced apart fins occupying a periphery thereof. A pressure control assembly includes a first adjustable control surface disposed adjacent to a first face of the foil so as to be selectively movable over the fins of the foil. The pressure control assembly may include a second control surface disposed adjacent to the second face of the foil and which may be adjustable. As the foil is rotated, and the at least one adjustable control surface is moved over fins of the foil, a fluid pressure imbalance is created, causing a thrust in the direction of the pressure deficit.

Abstract: A circular foil connectable to a source of power for producing thrust in an axial direction when rotated, includes a flat circular plate and a plurality of closely spaced-apart fins fixed to an upper face of the circular plate, which occupy substantially the entire peripheral portion of the plate. A cylindrical hoop is fixed to the plate adjacent to radially inwardly extending edges of the fins to prevent fluid disposed adjacent to the circular plate and radially inwardly of the fins, from flowing radially outwardly and into the space between the fins as the circular foil is rotated. The foil is rotated at a sufficient speed to discharge fluid molecules from spaces between the fins at a rate faster than they can be replenished. This creates an imbalance of fluid pressure on the first side of the foil relative to an opposite second side thereof. As a result, the circular foil moves in the direction of the deficit.