Aircraft having improved performance with beaver-tail afterbody configuration

In a supersonic aircraft having propulsion means, stabilizer fin means and a supersonic configuration fuselage provided with wings extending to opposite sides thereof, the improved fuselage that has a cambered airfoil configuration of high fineness ratio in which the airfoil fuselage extends flat-like and is cambered substantially continuously from the forebody portion of the fuselage to the trailing edge thereof and defines a relatively wide flat-like afterbody portion having a transversely hinged auxiliary pitch control means forming the fuselage trailing edge comprising:

• a supersonically faired fuselage forebody component for accommodating the aircraft crew and for housing conventional apparatus and instruments for operation and control of the aircraft;
• a fuselage afterbody component having a beaver-tail-like planform and a longitudinally cambered airfoil cross-sectional profile with a relatively wide flat-like lateral cross-sectional for effecting optimum pitch trim while operating in a desired supersonic speed regime;
• a fuselage intervenient body component adapted for attachment of aircraft wings thereto and having a generally flat-like lateral cross-section flattening progressively from the forebody component towards the rear of the aircraft so as to aerodynamically blend and fair said forebody into said afterbody,
• said fuselage forebody component extending from the aircraft nose to about the area of attachment of the forward portion of the wing structure to the fuselage;
• the intervenient body component extending therefrom aft to about the area of attachment of the rear portion of the wing to the fuselage;
• and the afterbody component extending therefrom aft to the rearmost edge or tip of the airplane fuselage;
• the upper and lower surfaces of said fuselage intervenient and fuselage afterbody components forming a substantially smoothly continuous airfoil section extending continuously from said forebody component to the trailing edge of said afterbody component, the upper surface of the fuselage intervenient body component extending as a flat-like substantially constant transverse curvature throughout substantially the full longitudinal extent of the intervenient body component and at least a portion of said afterbody component
• attachment means carried by said intervenient body component for affixing aircraft wing structure thereto so as to extend on opposite sides thereof;
• said forebody component, intervenient body component and afterbody component forming a high fineness ratio fuselage cambered longitudinally substantially continuously throughout said fuselage intervenient and afterbody components;
• the rearmost portion of said afterbody component being hinged for movement about a line transverse thereof to form the fuselage trailing edge portion as an auxiliary pitch control means which can be angled up and down above and below the mean camberline of the fuselage forward of said line so as to alter fuselage longitudinal camber for control of aircraft trim and pitch.

In a supersonic aircraft having propulsion means, stabilizer fin means and a supersonic configuration fuselage provided with wings extending to opposite sides thereof, the improved fuselage that has a cambered airfoil configuration of high fineness ratio defining a relatively wide flat-like afterbody portion having a transversely hinged auxiliary pitch control means forming the fuselage trailing edge comprising:

• A. a supersonically faired fuselage forebody component for accommodating the aircraft crew and for housing conventional apparatus and instruments for operation and control of the aircraft;
• B. a fuselage afterbody component having a beaver-tail-like planform and a longitudinally cambered airfoil cross-sectional profile with a relatively wide flat-like lateral cross-section for effecting optimum pitch trim while operating in a desired supersonic speed regime;
• C. a fuselage intervenient body component adapted for attachment of aircraft wings thereto and having a generally flat-like lateral cross-section flattening progressively from the forebody component towards the rear of the aircraft so as to aerodynamically blend and fair said forebody into said afterbody,
• upper and lower surfaces of said intervenient and afterbody components being substantially smoothly continuous airfoil surfaces from said forebody component to the trailing edge of said afterbody component;
• D. attachment means carried by said intervenient body component for affixing aircraft wing structure thereto so as to extend on opposite sides thereof;
• E. said forebody component, intervenient body component and afterbody component forming a high fineness ratio fuselage having longitudinal camber in said fuselage afterbody component;
• F. the rearmost portion of said afterbody component being hinged for movement about a line transverse thereof to form the fuselage trailing edge portion as an auxiliary pitch control means which can be angled up and down above and below the mean camberline of the fuselage forward of said line so as to alter fuselage longitudinal camber for control of aircraft trim and pitch;
• G. airbrake means on said fuselage afterbody component in association with said auxiliary pitch control means and including upper and lower braking panels adapted to lie flat-like against outer-directed control surfaces of the auxiliary pitch control means so as to form at least a portion of the effective control surfaces thereof when in retracted position;
• means for moving said panels away from said pitch control means into the airstream passing over said fuselage afterbody component to create an air flow passage between the panels and the pitch control means when the airbrake means is to be deployed;
• and
• H. vertical translation means operatively connecting said braking panels with said auxiliary pitch control means for maintaining a substantially constant planar relation therebetween as the said airflow passage is varied during movement of the panels into and out of the airstream passing over said pitch control means, whereby laminar airflow is sustained over the control surfaces thereof to maintain the effectiveness of said pitch control means for aircraft trim and pitch control when the braking panels are so moved.