A propeller having a plurality of blades extending radially outward from a hub, the blades forming a loop. Each loop can have an intake portion, an exhaust portion and a tip portion extending radially outward from the hub and a gap between the intake root and the exhaust root.

A propeller having a central post to which one or more blades are connected. The blades are disposed and configured to pull air in from the propeller's sides toward the propeller's axis of rotation to create pressure in an area in the vicinity of the center of the propeller's rotating axis for generating thrust.

A propeller having a means for creating fluid flow in a non-axial direction and redirecting it in an axial direction.

A propeller having a means for creating fluid flow in a non-axial direction and redirecting it in an axial direction.

A duo propeller disclosed having a forward propeller having increased loading distribution and high swirl near the tip. The duo propeller has an aft propeller with a more optimal loading distribution that can cancel the high tip swirl from the forward propeller. The duo-propeller an enhanced ability for the aft propeller to capture the energy lost to the swirling flow of the forward propeller's outflow.

A propeller having a plurality of blades extending radially outward from a hub, the blades forming a loop. Each loop can have an intake portion, an exhaust portion and a tip portion extending radially outward from the hub and a gap between the intake root and the exhaust root.

A duo propeller disclosed having a forward propeller having increased loading distribution and high swirl near the tip. The duo propeller has an aft propeller with a more optimal loading distribution that can cancel the high tip swirl from the forward propeller. The duo-propeller an enhanced ability for the aft propeller to capture the energy lost to the swirling flow of the forward propeller's outflow.

A propeller having a plurality of blades extending radially outward from a hub, the blades forming a loop. Each loop can have an intake portion, an exhaust portion and a tip portion extending radially outward from the hub and a gap between the intake root and the exhaust root.