Abstract: A large diameter propeller for starting a watercraft or aircraft has blades which fold forward about tangents along the hub circuit for very high speed operation. Then, the flank pressure radial to the propeller axis will reduce induction, cavitation, noise and centrifugal power, and as a consequence, the radial acceleration of the seized medium (while the speed of the traveling craft is very high) will be so slow that turbulances resulting in propulsion losses are minimized.

Abstract: A propeller hub rotatable about an axis is provided with a plurality of airfoil surfaces peripherally arranged about the axis and defining a first pitch angle that is acute and adjustable with respect to the tangent on the circular arc described by rotation of the airfoil surface as seen in a plane perpendicular to the axis, and further by a second pitch angle being acute and adjustable and measured with respect to the axis of rotation within a plane containing the axis of rotation. Peripherally adjacent airfoil surfaces may have their first pitch angles oppositely oriented and second pitch angles oppositely oriented to respectively propel fluid inwardly and outwardly with respect to the axis of rotation. The air foil surfaces may be directly connected to the hub and extend conically outward or connected to the hub by means of arms that may be angled airfoil surfaces functioning as conventional screw propellers. The hub may be mounted coaxially adjacent a counter rotating screw.

Abstract: A propeller hub rotatable about an axis is provided with a plurality of airfoil surfaces peripherally arranged about the axis and defining a first pitch angle that is acute and adjustable with respect to the tangent on the circular arc described by rotation of the airfoil surface as seen in a plane perpendicular to the axis, and further by a second pitch angle being acute and ajustable and measured with respect to the axis of rotation within a plane containing the axis of rotation. Peripherally adjacent airfoil surfaces may have their first pitch angles oppositely oriented and second pitch angles oppositely oriented to respectively propel fluid inwardly and outwardly with respect to the axis of rotation. The air foil surfaces may be directly connected to the hub and extend conically outward or connected to the hub by means of arms that may be angled airfoil surfaces functioning as conventional screw propellers. The hub may be mounted coaxially adjacent a counter rotating screw.

Abstract: A drive for submerged portions of floating bodies, i.e. watercraft comprising a pulsating nozzle including a control device for pulsating the nozzle by expansion and contraction of an open inner nozzle diameter portion. The control device contracts and expands the nozzle such that during expansion the front of the nozzle is expanded to a greater extent than the rear of the nozzle to produce a positive angle of attack, and during contraction the rear of the nozzle remains expanded to a greater extent than the front of the nozzle to produce a negative angle of attack.

Abstract: The invention relates to a flank drive for propelling a boat wherein a plurality of propeller housings are rotatably mounted in a wheel body about and in driving engagement with a normally stationary guide wheel centrally of the wheel body, which wheel body is rotated about its own central axis by means of a propulsion motor to carry the housings about the wheel body axis and rotate the housings about their own axes, so that the propeller housings undergo epicyclic motion.The propeller blade in each propeller housing can be adjusted relative to its housing passively by relative motion between abuttments or positively by means of an automatic hydraulic control to the most effective angle of attack, whereby the blades mainly exert flank force to the surrounding water. The guide wheel may be swivelled to steer the boat.