Aircraft having helicopter rotor and front mounted propeller

Abstract

An aircraft features a nose mounted propeller on a fuselage having a typical helicopter rotor assembly. By reducing the amount of forward thrust needed from the main rotor, the propeller allows greater forward speeds as the angle of attack on the rotor's blades can be kept low to avoid the stalling and violent vibration experienced by conventional helicopters at relatively high speeds. By greatly reducing the amount of thrust produced by the main rotor but still using it to generate lift, the addition of wings can be avoided. The aircraft can be flown in a forward direction in a generally horizontal orientation, as the nose does not have to be pitched downward to create thrust from the main rotor.

1 . An aircraft comprising:
 a fuselage having a front end and a longitudinal axis;   a main helicopter rotor supported for rotation about an axis thereof on top of the fuselage, said rotor being operable to control both vertical and horizontal movement of the aircaft;   a propeller supported for rotation about an axis thereof at the front end of the fuselage operable to selectively produce thrust to move the aircraft forward; and   at least one powerplant supported on the fuselage;   the main rotor and propeller each being operatively connected to the at least one powerplant for selective driven rotation thereby;   wherein on at least one side of the fuselage, vertical lift is provided substantially wholly by the main helicopter rotor during forward cruising.   
     
     
         2 . The aircraft according to  claim 1  wherein the at least one powerplant comprises a propeller powerplant and a rotor powerplant, the propeller and main helicopter rotor being operatively connected to the propeller and rotor powerplants respectively. 
     
     
         3 . The aircraft according to  claim 1  wherein the at least one powerplant comprises a common powerplant having a rotor output and a propeller output, the propeller and main helicopter rotor being operatively connected to the propeller and rotor outputs respectively. 
     
     
         4 . The aircraft according to  claim 1  wherein the propeller is adjustable in pitch. 
     
     
         5 . The aircraft according to  claim 1  further comprising a clutch operable to couple and decouple the propeller and the at least one powerplant. 
     
     
         6 . The aircraft according to  claim 1  wherein the main helicopter rotor, at a forwardmost point of its rotation, and the propeller, at an uppermost point in its rotation, move in a common direction. 
     
     
         7 . The aircraft according to  claim 6  further comprising a horizontal stabilizer supported rearward of the fuselage and extending obliquely with respect to the longitudinal axis of the fuselage so as to extend downward from front to rear. 
     
     
         8 . The aircraft according to  claim 7  wherein the horizontal stabilizer is disposed rearward of a tail rotor supported for rotation rearward of the fuselage. 
     
     
         9 . The aircraft according to  claim 6  wherein the propeller is supported for rotation in a plane generally perpendicular to a rotational plane of the main helicopter rotor. 
     
     
         10 . The aircraft according to  claim 1  wherein the main helicopter rotor, at a forwardmost point in its rotation, and the propeller, in an uppermost point in its rotation, move in opposite directions. 
     
     
         11 . The aircraft according to  claim 10  further comprising a horizontal stabilizer supported rearward of the fuselage and extending obliquely with respect to the longitudinal axis of the fuselage so as to extend upward from front to rear. 
     
     
         12 . The aircraft according to  claim 11  wherein the horizontal stabilizer is disposed rearward of a tail rotor supported for rotation rearward of the fuselage. 
     
     
         13 . The aircraft according to  claim 10  wherein the propeller being supported for rotation in a plane transverse to the fuselage, said plane being inclined with respect to the longitudinal axis of the fuselage so as to extend upward from front to rear with said longitudinal axis horizontally oriented. 
     
     
         14 . The aircraft according to  claim 10  wherein the propeller being supported for rotation in a plane transverse to the fuselage, said plane being inclined with respect to the longitudinal axis of the fuselage so as to extend downward from front to rear with said longitudinal axis horizontally oriented. 
     
     
         15 . The aircraft according to  claim 1  further comprising a wing extending laterally from one side of the fuselage to counter dissymmetry of lift of the main helicopter rotor during forward flight. 
     
     
         16 . A method of flying an aircraft comprising a fuselage having a front end and a longitudinal axis, a main helicopter rotor supported for rotation about an axis thereof on top of the fuselage, said rotor being operable to control both vertical and horizontal movement of the aircraft, and a propeller supported for rotation about an axis thereof at the front end of the fuselage operable to selectively produce thrust to move the aircraft forward, the method comprising:
 transitioning from hover or other in-flight manoeuvre to forward flight;   providing half of an amount of vertical lift needed to maintain an altitude of the aircraft during forward flight on a first side of the fuselage substantially wholly by powering the main helicopter rotor;   providing a remaining half of the amount of vertical lift needed to maintain the altitude of the aircraft during forward flight on a second side of the fuselage opposite the first side; and   powering the propeller to provide forward thrust of the aircraft in forward flight.   
     
     
         17 . The method according to  claim 16  wherein transitioning to forward flight comprises adding forward cyclic to create forward thrust from the main helicopter rotor, increasing power to the propeller as the aircraft beings moving forward and removing the forward cyclic. 
     
     
         18 . The method according to  claim 17  wherein transitioning to forward flight further comprises adding rearward cyclic to pitch the front end of the fuselage upward. 
     
     
         19 . The method according to  claim 16  wherein powering the main helicopter rotor provides substantially wholly the remaining half of the amount of vertical lift needed to maintain the altitude of the aircraft during forward flight on the opposite side of the fuselage. 
     
     
         20 . The methods according to  claim 16  wherein flowing air around a wing extending laterally from the fuselage on the second side thereof, and powering the main helicopter rotor, together provide substantially wholly the remaining half of the amount of vertical lift needed to maintain the altitude of the aircraft during forward flight.