Abstract: Vortex reduction apparatus for use with airfoils are disclosed. An example vortex reduction apparatus includes a housing to couple to a tip of an airfoil. The housing defines a volute fluid flow passageway between an inlet and an outlet. The volute fluid flow passageway is structured to induce a rotational fluid flow in a first rotational direction opposite a second rotational direction of a shed vortex induced at the tip of the airfoil during flight.

Abstract: Vortex reduction apparatus for use with airfoils are disclosed. An example vortex reduction apparatus includes a housing to couple to a tip of an airfoil. The housing defines a volute fluid flow passageway between an inlet and an outlet. The volute fluid flow passageway is structured to induce a rotational fluid flow in a first rotational direction opposite a second rotational direction of a shed vortex induced at the tip of the airfoil during flight.

Abstract: Systems and methods for rotor/wing aircraft are disclosed. In one embodiment, an aircraft includes an airframe, a high-lift canard and tail, a rotor/wing, a propulsion system, and a drive assembly. The drive assembly, which may include a radial inflow turbine, is configured to extract work from the propulsion system to selectively rotate the rotor/wing assembly thus enabling the aircraft to conduct rotary-wing flight, fixed wing flight as well as smoothly transition between the two modes of flight.

Abstract: A hub fairing system (12) for a stopped-rotor aircraft (10) having a fuselage (14) including a hub (16). The hub (16) is mechanically coupled to the fuselage (14) and to multiple blades (40) and is rotated by an engine (22). A retractable fairing (60, 64) covers a portion of the hub (16). An actuator (26) is coupled to the fairing (60, 64). A controller (28) is coupled to the actuator (26) and retracts the fairing (60, 64). A method of reducing drag on the aircraft includes transitioning between a rotary-wing mode and a fixed-wing mode. The fairing (60, 64) is deployed over a portion of the hub (16) upon the completion of the transition between flight modes.

Abstract: A hub fairing system (12) for a stopped-rotor aircraft (10) having a fuselage (14) including a hub (16). The hub (16) is mechanically coupled to the fuselage (14) and to multiple blades (40) and is rotated by an engine (22). A retractable fairing (60, 64) covers a portion of the hub (16). An actuator (26) is coupled to the fairing (60, 64). A controller (28) is coupled to the actuator (26) and retracts the fairing (60, 64). A method of reducing drag on the aircraft includes transitioning between a rotary-wing mode and a fixed-wing mode. The fairing (60, 64) is deployed over a portion of the hub (16) upon the completion of the transition between flight modes.

Abstract: Aircraft including an airframe having a fuselage extending between a forward end and an aft end. The aircraft further includes a power plant mounted on the airframe producing exhaust during operation. The aircraft also includes a rotor/wing including a plurality of blades connected to a drive shaft rotatably mounted on the airframe and a radial inflow turbine mounted on the airframe in fluid communication with the power plant for receiving exhaust from the power plant. The radial inflow turbine includes a body forming an annular vortical chamber having an upper portion and a lower portion. The radial inflow turbine also includes a hub rotatably connected to the body and operatively connected to the drive shaft. In addition, the radial inflow turbine includes a plurality of vanes extending radially outward from the hub. The hub and the vanes are positioned in the vortical chamber.

Abstract: Systems and methods for rotor/wing aircraft are disclosed. In one embodiment, an aircraft includes an airframe, a high-lift canard and tail, a rotor/wing, a propulsion system, and a drive assembly. The drive assembly, which may include a radial inflow turbine, is configured to extract work from the propulsion system to selectively rotate the rotor/wing assembly thus enabling the aircraft to conduct rotary-wing flight, fixed wing flight as well as smoothly transition between the two modes of flight.

Abstract: A hub fairing system (12) for a stopped-rotor aircraft (10) having a fuselage (14) including a hub (16). The hub (16) is mechanically coupled to the fuselage (14) and to multiple blades (40) and is rotated by an engine (22). A retractable fairing (60, 64) covers a portion of the hub (16). An actuator (26) is coupled to the fairing (60, 64). A controller (28) is coupled to the actuator (26) and retracts the fairing (60, 64). A method of reducing drag on the aircraft includes transitioning between a rotary-wing mode and a fixed-wing mode. The fairing (60, 64) is deployed over a portion of the hub (16) upon the completion of the transition between flight modes.

Abstract: Aircraft including an airframe having a fuselage extending between a forward end and an aft end and a fixed wing extending laterally from the fuselage. The aircraft includes a power plant mounted on the airframe producing exhaust during operation. The aircraft includes a rotor/wing rotatably mounted on the airframe including a plurality of blades and an adjustable nozzle mounted on the airframe downstream from the power plant exhaust for selectively directing the power plant exhaust to exit the aircraft at a pre-selected angle with respect to the airframe within a range of angles extending from about horizontally rearward to about vertically downward.

Abstract: A hub fairing system (12) for a stopped-rotor aircraft (10) having a fuselage (14) including a hub (16). The hub (16) is mechanically coupled to the fuselage (14) and to multiple blades (40) and is rotated by an engine (22). A retractable fairing (60, 64) covers a portion of the hub (16). An actuator (26) is coupled to the fairing (60, 64). A controller (28) is coupled to the actuator (26) and retracts the fairing (60, 64). A method of reducing drag on the aircraft includes transitioning between a rotary-wing mode and a fixed-wing mode. The fairing (60, 64) is deployed over a portion of the hub (16) upon the completion of the transition between flight modes.