Directional and stabilizing device having a faired and slanted antitorque rotor and a disymmetric "V" empennage, and a helicopter equipped with such a device

A directional and stabilizing device for aircraft with rotating wings including at least one rotor which, in lift rotor configuration, is driven mechanically in rotation by at least one engine while absorbing the drive power at least partially, and whose fuselage is subjected to the reaction of the drive torque driving the lift rotor, which reaction must be compensated for, said device being of the type comprising in combination:

• a faired antitorque rotor, including a multiblade variable pitch propeller mounted coaxially in a faired aperture of circular section formed transversally in a fairing situated at the rear of the fuselage, and driven in rotation about the axis of said aperture, and
• a "V" empennage carried by the fairing housing the faired rotor and having two aerodynamic surfaces disposed in a V, which are joined together at the top of the fairing housing the faired rotor without coming below a horizontal plane passing through this top, wherein
• the mean plane of the fairing housing the faired rotor and the plane of rotation of the faired rotor are slanted with respect to the plane of symmetry of the aircraft by an angle situated in an angular range going from greater than 0.degree. to 45.degree.,
• the direction of rotation of the faired rotor and the pitch control of the blades of the rotor are arranged so that, said blades being controlled at a positive pitch, the resultant thrust along the axis of the rotor is directed in a direction such that the component of said thrust parallel to the general transverse axis of the aircraft creates, on the fuselage, with respect to the axis of the main rotor, a moment opposing the drive torque of the main rotor, and the component of this same thrust parallel to the general vertical axis of the aircraft is directed upwards,
• each of the two aerodynamic surfaces has a mean plane and the two mean planes extend on each side of the vertical plane including the general longitudinal axis of the aircraft, the mean plane of the first aerodynamic surface is placed, with respect to the vertical plane, on the side which is opposite that towards which the thrust of the antitorque rotor is directed in stationary flight whereas the mean plane of the second aerodynamic surface is placed, with respect to the vertical plane, on the side towards which the thrust of the antitorque rotor is directed in stationary flight,
• the mean plane of the first aerodynamic surface forms with the horizontal an angle situated in an angular range from 0.degree. to 45.degree. whereas the mean plane of the second aerodynamic surface forms with the vertical an angle situated in an angular range going from 0.degree. to 45.degree.,
• said first aerodynamic surface has an aerodynamic profile such that, in translational flight, it generates a resultant aerodynamic force with a vertical negative lift component directed downwardly, and
• said second aerodynamic surface has an aerodynamic profile such that, in translational flight, it generates a resultant aerodyanmic force having a component parallel to the general transverse axis of the aircraft directed in the same direction as the component, along the same axis, of the thrust of the antitorque rotor and a component parallel to the general vertical axis of the aircraft, directed downwardly.