Aircraft propeller

Abstract

A VTOL fixed wing aircraft capable of high-speed forward flight. The aircraft has a main wing internally reinforced with front and aft spars. Spar boxed are located in roll-balanced locations along the wing. Each spar box serves as a connection point for a support linkage that supports a leading-edge and trailing-edge propulsion units. The leading-edge propulsion unit is fitted with a puller propeller and designed for articulated movement between a VTOL position in front of the wing leading edge and a forward flight position below the wing leading edge. The trailing-edge propulsion unit is fitted with a pusher propeller and designed for articulated movement between a VTOL position in behind the wing trailing edge and a forward flight position above the wing leading edge. The propeller includes a propulsor thrust ring having an aerodynamic profile and a thrust nozzle to capture and vector radial air leakage into thrust.

1 - 17 . (canceled) 
     
     
         18 . A propeller adapted for operative attachment to the output shaft of a propulsion motor for a fixed wing aircraft assembly, said propeller comprising:
 a hub defining a rotary axis,   a plurality of blades extending radially from said hub, each said blade terminating at a distal tip,   an annular propulsor thrust ring concentrically disposed about said hub, said propulsor thrust ring joining each of said tips of said blades into a monolithic structure, said propulsor thrust ring having an aerodynamic cross-sectional profile as taken in a radial plane intersecting said rotary axis of said hub, said aerodynamic profile having an interior surface and an exterior surface, said interior and exterior surfaces of said aerodynamic profile converging at a leading rim and a trailing rim, said aerodynamic profile having a PTR angle of attack (AOA) that is generally parallel to or diverging relative to said rotary axis,   and wherein said trailing rim has a thrust nozzle conically converging airflow toward said rotary axis at a thrust angle (θ) measured with respect to said PTR angle of attack (AOA).   
     
     
         19 . The propeller of  claim 18  wherein said aerodynamic profile has a PTR angle of attack (AOA) that diverges relative to said rotary axis in the forward direction of flight, said exterior surface of said aerodynamic profile defined by a continuously convex curve, said interior surface of said aerodynamic profile defined by an ogee curve, and said ogee curve is convex adjacent said leading rim and concave adjacent said trailing rim. 
     
     
         20 . The propeller of  claim 18  wherein each said blade has an overall blade length (OAL), each said blade having a leading blade edge and a trailing blade edge, said leading blade edge having a maximum span at a radial distance between about 0.3 and 0.4 times said overall blade length (OAL) as measured from said hub, each said blade having a varied blade pitch, the pitch (HP) of said blade adjacent said hub being greater than the pitch (RP) of said blade adjacent said propulsor thrust ring. 
     
     
         21 . The propeller of  claim 18  wherein said aerodynamic profile has a PTR angle of attack (AOA) that diverges relative to said rotary axis in the forward direction of flight. 
     
     
         22 . The propeller of  claim 18  wherein said exterior surface of said aerodynamic profile is defined by a continuously convex curve. 
     
     
         23 . The propeller of  claim 22  wherein said interior surface of said aerodynamic profile is defined by an ogee curve. 
     
     
         24 . The propeller of  claim 23  wherein and said ogee curve is convex adjacent said leading rim and concave adjacent said trailing rim. 
     
     
         25 . The propeller of  claim 18  wherein each said blade has an overall blade length (OAL), each said blade having a leading blade edge and a trailing blade edge, said leading blade edge having a maximum span at a radial distance between about 0.3 and 0.4 times said overall blade length (OAL) as measured from said hub. 
     
     
         26 . The propeller of  claim 18  wherein each said blade has a varied blade pitch. 
     
     
         27 . The propeller of  claim 27  wherein the pitch (HP) of said blade adjacent said hub is greater than the pitch (RP) of said blade adjacent said propulsor thrust ring. 
     
     
         28 . A propeller adapted for operative attachment to the output shaft of a propulsion motor for a fixed wing aircraft assembly, said propeller comprising:
 a hub defining a rotary axis,   a plurality of blades extending radially from said hub, each said blade terminating at a distal tip,   an annular propulsor thrust ring concentrically disposed about said hub, said propulsor thrust ring joining each of said tips of said blades into a monolithic structure, said propulsor thrust ring having an aerodynamic cross-sectional profile as taken in a radial plane intersecting said rotary axis of said hub, said aerodynamic profile having an interior surface and an exterior surface, said interior and exterior surfaces of said aerodynamic profile converging at a leading rim and a trailing rim, said aerodynamic profile having a PTR angle of attack (AOA) that is generally parallel to or diverging relative to said rotary axis, said aerodynamic profile having a PTR angle of attack (AOA) that diverges relative to said rotary axis in the forward direction of flight, said exterior surface of said aerodynamic profile defined by a continuously convex curve, said interior surface of said aerodynamic profile defined by an ogee curve, and said ogee curve is convex adjacent said leading rim and concave adjacent said trailing rim,   wherein said trailing rim has a thrust nozzle conically converging airflow toward said rotary axis at a thrust angle (θ) measured with respect to said PTR angle of attack (AOA)   and wherein each said blade has an overall blade length (OAL), each said blade having a leading blade edge and a trailing blade edge, said leading blade edge having a maximum span at a radial distance between about 0.3 and 0.4 times said overall blade length (OAL) as measured from said hub, each said blade having a varied blade pitch, the pitch (HP) of said blade adjacent said hub being greater than the pitch (RP) of said blade adjacent said propulsor thrust ring.   
     
     
         29 . A fixed wing aircraft and propeller assembly, comprising:
 an airframe comprising an elongated fuselage extending between nose and tail ends, at least one main wing fixed to said fuselage between said nose and tail ends,   a propulsion system supported from said main wing, said propulsion system including a motor having an output shaft turned about a rotary axis,   a propeller fixedly attached to said output shaft for driven rotation, said propeller having a hub directly attached to said output shaft along a common rotary axis,   a plurality of blades extending radially from said hub, each said blade terminating at a distal tip,   an annular propulsor thrust ring concentrically disposed about said hub, said propulsor thrust ring joining each of said tips of said blades into a monolithic structure, said propulsor thrust ring having an aerodynamic cross-sectional profile as taken in a radial plane intersecting said rotary axis of said hub, said aerodynamic profile having an interior surface and an exterior surface, said interior and exterior surfaces of said aerodynamic profile converging at a leading rim and a trailing rim, said aerodynamic profile having a PTR angle of attack (AOA) that is generally parallel to or diverging relative to said rotary axis,   and wherein said trailing rim has a thrust nozzle conically converging airflow toward said rotary axis at a thrust angle (θ) measured with respect to said PTR angle of attack (AOA).   
     
     
         30 . The assembly of  claim 29  wherein said motor comprises an electric motor. 
     
     
         31 . The assembly of  claim 29  wherein said aerodynamic profile has a PTR angle of attack (AOA) that diverges relative to said rotary axis in the forward direction of flight. 
     
     
         32 . The assembly of  claim 29  wherein said exterior surface of said aerodynamic profile is defined by a continuously convex curve. 
     
     
         33 . The assembly of  claim 32  wherein said interior surface of said aerodynamic profile is defined by an ogee curve. 
     
     
         34 . The assembly of  claim 33  wherein and said ogee curve is convex adjacent said leading rim and concave adjacent said trailing rim. 
     
     
         35 . The assembly of  claim 29  wherein each said blade has an overall blade length (OAL), each said blade having a leading blade edge and a trailing blade edge, said leading blade edge having a maximum span at a radial distance between about 0.3 and 0.4 times said overall blade length (OAL) as measured from said hub. 
     
     
         36 . The assembly of  claim 29  wherein each said blade has a varied blade pitch. 
     
     
         37 . The assembly of  claim 36  wherein the pitch (HP) of said blade adjacent said hub is greater than the pitch (RP) of said blade adjacent said propulsor thrust ring.