Abstract: The present disclosure provides a rotating propeller design that maintains a high efficiency and reduces noise. The design provides an unloaded tip zone of positive lift starting prior to an end of the tip with negligible, if any, positive lift that is counterintuitive to the purpose of a propeller. The unloaded tip zone decreases the strength of a tip vortex and reduces induced drag. The result is a significant reduction in noise while maintaining substantially high mechanical efficiency, even with an optional increase in RPM to compensate for the reduced lift without requiring a longer propeller. At least one propeller design can break the beta angle from the propeller hub with a different beta angle at a first location from the hub and then also break the beta angle at a second location further from the hub into the unloaded tip zone to form a double break propeller.

Abstract: The present disclosure provides a rotating propeller design that maintains a high efficiency and reduces noise. The design provides an unloaded tip zone of positive lift starting prior to an end of the tip with negligible, if any, positive lift that is counterintuitive to the purpose of a propeller. The unloaded tip zone decreases the strength of a tip vortex and reduces induced drag. The result is a significant reduction in noise while maintaining substantially high mechanical efficiency, even with an optional increase in RPM to compensate for the reduced lift without requiring a longer propeller. At least one propeller design can break the beta angle from the propeller hub with a different beta angle at a first location from the hub and then also break the beta angle at a second location further from the hub into the unloaded tip zone to form a double break propeller.

Abstract: A system to improve jet engine powered aircraft performance and efficiency includes a jet engine having a pressurized air port configured to convey a pressurized airflow from a compressor or a bypass fan disposed in the jet engine. A primary airfoil has a trailing edge, a top surface, and a boundary region. The system further includes a secondary airfoil disposed at a distance from the top surface of the primary airfoil. The secondary airfoil has a bottom surface and a trailing edge. An exhaust region is formed by the trailing edge of the primary airfoil and the trailing edge of the secondary airfoil. A primary airfoil ejector port and a secondary airfoil ejector port are pneumatically coupled to the pressurized air port. The primary airfoil ejector port is disposed proximate the boundary region and the secondary airfoil ejector port is disposed on the bottom surface.