Propeller

A propeller comprising:

• a central post coincident with a rotational axis;
• one or more separate blades each having a distal end and a proximate end, each blade having an airfoil-shaped cross section;
• each of the one or more blades comprising a top section, a bottom section, and a side section, the side section disposed at or toward the distal end;
• a length from the central post to the distal end of each of the one or more blade's leading edge is greater than a length from the central post to the distal end of each of the one or more blade's trailing edge such that an outermost foil of the side section is configured to pull fluid inward from the side section of the one or more blades toward the propeller rotational axis by having a non-zero blade angle, wherein the blade angle is defined as the angle between a lateral cross section of a blade and the plane of rotation;
• the top section and the bottom section of each of the one or more blades connected at the proximate end to and extending radially outward from the central post;
• wherein the top section extends from the central post outward to the side section at a top section distal end and the side section folds back to the central post to a bottom section distal end so a top surface of the top section becomes a bottom surface of the bottom section;
• a gap between central post connections of the top section and bottom section of at least one of the one or more blades;
• and
• the one or more blades further configured to pull fluid from a propeller front end to a propeller back end;
• wherein the bottom section of the one or more blades forms a more extreme intersection angle with the central post than the top section of the one or more blades forms with the central post, wherein more extreme indicates more toward the vertical.