A T-tailed deltoid main wing aircraft having a symmetry plane and a transversal axis, said transversal axis being perpendicular to said symmetry plane, said symmetry plane including a longitudinal and a vertical axis, said longitudinal axis coinciding with airflow direction, said T-tailed deltoid main wing aircraft comprising:
- a) a main wing that has a plane of symmetry, said plane of symmetry of said main wing coinciding with said symmetry plane of said T-tailed deltoid main wing aircraft, the main wing planform being shaped as a deltoid, said deltoid having a longitudinal and a transversal diagonal, said longitudinal diagonal being a symmetry axis of said deltoid, said longitudinal diagonal coinciding with said longitudinal axis, said transversal diagonal being parallel to said transversal axis, said longitudinal diagonal having a leading and a trailing tip, said transversal diagonal having two lateral tips, said leading tip and said lateral tips being connected with two straight lines, thus forming a leading edge of said main wing, said trailing tip and said lateral tips being connected with two straight lines, thus forming a trailing edge of said main wing, the main wing cross-sections that coincide with airflow direction are shaped as airfoils, the main wing airfoil chords extending from the main wing leading edge to the main wing trailing edge, said main wing being the main airlifting surface of said T-tailed deltoid main wing aircraft, said main wing having an upper and an under surface, the main wing upper and under surfaces having smooth aerodynamic shapes, said main wing upper and under surfaces enclosing a space for payload disposal, the lengths of said longitudinal diagonal and said transversal diagonal determining the size of the airlifting surface area of said main wing, said longitudinal diagonal may have different longitudinal positions relatively to said transversal diagonal including a fore and an aft position, said longitudinal diagonal being in said fore position when said leading tip being farther away from said transversal diagonal than said trailing tip, while said longitudinal diagonal being in said aft position when said trailing tip being farther away from said transversal diagonal than said leading tip, said main wing leading edge having a sweepback, while said main wing trailing edge having a forward sweep, the length of said longitudinal diagonal, the length of said transversal diagonal, and the longitudinal position of said longitudinal diagonal relatively to said transversal diagonal being the only three geometric variables that are necessary to define and optimize said main wing planform, said three geometric variables affecting the aerodynamic variables and aerodynamic performance of said T-tailed deltoid main wing aircraft, the change of said length of said transversal diagonal affecting the size of the airlifting surface area of said main wing, as well as the main wing leading and trailing edge sweep angles, thus resulting with the change of friction, induced, and wave drag, as well as the lift capacity of said T-tailed deltoid main wing aircraft, while the change of said length of said longitudinal diagonal affecting the size of said airlifting surface area of said main wing, said main wing leading and trailing edge sweep angles, the length of the mean aerodynamic chord of said main wing, and the relative thickness of the main wing airfoils in the area where payload is disposed, thus resulting with the change of friction, induced, profile, and wave drag, as well as the change of lift and payload capacity of said T-tailed deltoid main wing aircraft, whereas the change of said longitudinal position of said longitudinal diagonal affecting said main wing leading and trailing edge sweep angles, the longitudinal position of the neutral point of said T-tailed deltoid main wing aircraft, as well as the longitudinal distance between said neutral point and the gravity center of said T-tailed deltoid main wing aircraft, thus resulting with the change of wave and induced drag, as well as the change of the longitudinal static and dynamic stability of said T-tailed deltoid main wing aircraft,
- b) two outer wings that are mutually symmetrical relatively to said symmetry plane, said outer wings being lateral airlifting surfaces of said T-tailed deltoid main wing aircraft, said outer wings are joined said main wing outwardly from said lateral tips, said outer wings may have different longitudinal positions relatively to said lateral tips, said outer wings having a root and a tip airfoil, as well as a leading and a trailing edge, said outer wings having a simple trapezoidal planform, the outer wings planform being defined with four geometric variables including the length of the outer wings root airfoil chord, the length of the outer wings tip airfoil chord, the distance between the outer wings root and tip airfoil chords in transversal direction, as well as the sweep angle of the outer wings leading edge, while the longitudinal position of said outer wings relatively to said lateral tips being the fifth geometric variable of said outer wings, the above five geometric variables of said outer wings affecting the airlifting surface area, aerodynamic sweep angle, span, and aspect ratio of said outer wings, thereby affecting induced, friction, profile, and wave drag, said lift capacity, said longitudinal static and dynamic stability, as well as the roll control of said T-tailed deltoid main wing aircraft,
- c) two wing transition sections that are mutually symmetrical relatively to said symmetry plane, said wing transition sections covering the outboard portions of said main wing in the vicinity of said lateral tips, said wing transition sections being additional airlifting surfaces of said T-tailed deltoid main wing aircraft, the wing transition sections planform being defined with a wing transition section leading edge and a wing transition section trailing edge, said wing transition section leading edge being tangentially joined said main wing leading edge and said outer wings leading edge, while said wing transition section trailing edge being tangentially joined said main wing trailing edge and the outer wings trailing edge, thus allowing for a smooth three-dimensional integration of said main wing and said outer wings into an integral airlifting surface of said T-tailed deltoid main wing aircraft, said wing transition section leading edge is having a smooth and a slightly concave shape, said slightly concave shape of said wing transition section leading edge providing for a highly aerodynamically efficient leading edge across the span of the entire said integral airlifting surface, while said wing transition section trailing edge is having a significantly more pronounced concave shape, the curvature radii of said wing transition section trailing edge are adjusted to provide for both the smooth aerodynamic transition between said main wing and said other wings in transversal direction and the lowest possible forward sweep angles of said wing transition section trailing edge in order to minimize both the interference drag between said main wing and said outer wings and the vortex activity around said wing transition sections, the shape and size of said wing transition section leading edge and said wing transition section trailing edge are geometric variables of said wing transition sections that are affecting the aerodynamic variables and performance of said T-tailed deltoid main wing aircraft, the change of said shape and size of said wing transition section leading edge and said wing transition section trailing edge is affecting the size of the surface area of said integral airlifting surface, the smoothness of the aerodynamic transition between said main wing and said outer wings in transversal direction, as well as the longitudinal position of the mean aerodynamic chord of said integral airlifting surface relatively to the aircraft gravity center, thereby affecting said friction, interference, and induced drag, lift capacity, as well as the level of application of efficient airfoils with aft camber and consequently the profile drag of said T-tailed deltoid main wing aircraft,
- d) at least two lateral jet engine nacelles with pylons that are mutually symmetrical relatively to said symmetry plane, the jet engine nacelles being fastened to the top of jet engine pylons, said jet engine pylons being fastened to the rear portion of said integral airlifting surface as rear cantilevers, said jet engine pylons overlapping said integral airlifting surface in upward, downward, and aft directions, the vertical position of said top of said jet engine pylons being adjusted to minimize the negative influence of the boundary layer of the upper surface of said integral airlifting surface on jet engine efficiency, said jet engine nacelles with pylons separate the airflow over the rear portion of said integral airlifting surface from the free airflow outboard of said jet engine nacelles with pylons, thus acting as winglets of said rear portion of said integral airlifting surface, thereby significantly reducing the vortex activity around said rear portion of said integral airlifting surface, hence reducing the induced drag of said T-tailed deltoid main wing aircraft, said jet engine pylons that are positioned on both lateral sides of said rear portion of said integral airlifting surface are additionally acting as air deflectors, thus significantly decreasing the airflow slip in lateral direction over a highly curved upper surface of said rear portion of said integral airlifting surface, thereby increasing the aerodynamic efficiency of said rear portion of said integral airlifting surface, the length and height of said jet engine pylons, as well as the lateral position thereof being optimized to minimize total drag including the friction drag of said jet engine pylons, induced drag over said rear portion of said integral airlifting surface, as well as the increased compression drag over said rear portion of said integral airlifting surface at higher subsonic speeds that is caused by the presence of said jet engine nacelles with pylons,
- e) at least two jet engine pylon transition sections being mutually symmetrical relatively to said symmetry plane, said jet engine pylon transition sections closing the gap between said jet engine pylons and the trailing edge of said integral airlifting surface in the area where said jet engine pylons are overlapping the trailing edge of said rear portion of said integral airlifting surface, said jet engine pylon transition sections preventing the vortex activity around said rear portion of said integral airlifting surface, said jet engine pylon transition sections being the constituent part of said integral airlifting surface, hence increasing the airlifting surface area of said T-tailed deltoid main wing aircraft, while additionally reducing the induced and interference drag in the area of said jet engine pylons,
- f) a fin with rudder that is symmetrical relatively to said symmetry plane, said fin with rudder being joined the upper side of said main wing in the vicinity of said trailing tip, said fin with rudder is significantly increasing directional stability and yaw control of said T-tailed deltoid main wing aircraft, the height and aerodynamic sweepback angle of said fin with rudder are allowing said fin with rudder to provide for the efficient yaw control of said T-tailed deltoid main wing aircraft in all flight regimes, said fin being additionally used as connecting means by which a main aerodynamic surface for pitch control of said T-tailed deltoid main wing aircraft is fastened to said main wing, said fin having a rigid airframe, said airframe of said fin being fastened to the main wing airframe, said fin with rudder may have different longitudinal positions relatively to said main wing including the outermost aft position thereof, said outermost aft position of said fin with rudder allowing for a viable connection between the fin airframe and said main wing airframe, said viable connection between said fin airframe and said main wing airframe are providing for the efficient transfer of all aerodynamic and inertia forces generated by said fin with rudder, as well as the transfer of all aerodynamic and inertia forces generated by said main aerodynamic surface for pitch control of said T-tailed deltoid main wing aircraft into said main wing airframe,
- g) a tailplane that is symmetrical relatively to said symmetry plane, said tailplane being said main aerodynamic surface for pitch control of said T-tailed deltoid main wing aircraft, said tailplane having a root and a tip airfoil, as well as a leading and a trailing edge, said tailplane having a simple planform, the tailplane planform being defined by four geometric variables including the length of the tailplane root airfoil chord, the length of the tailplane tip airfoil chord, the distance between the tailplane root and tip airfoil chords in transversal direction, as well as the sweep angle of the tailplane leading edge, said tailplane being joined said fin, said tailplane having a rigid airframe, the tailplane airframe being fastened to said fin airframe, said tailplane may have different longitudinal positions relatively to said fin including the outermost aft position thereof, said outermost aft position of said tailplane relatively to said fin allowing for a viable connection between said tailplane airframe and said fin airframe, said viable connection between said tailplane airframe and said fin airframe providing for the effective transfer of aerodynamic and inertia forces of said tailplane into said fin airframe, the longitudinal position of said tailplane relatively to said fin, the longitudinal position of said fin relatively to said main wing, as well as said height and aerodynamic sweepback angle of said fin with rudder being additional four geometric variables of said tailplane that define the longitudinal position of said fin with rudder and said tailplane relatively to said integral airlifting surface, thus the above total of eight geometric variables of said tailplane and said fin with rudder having a significant influence on the longitudinal position of the neutral point of said T-tailed deltoid main wing aircraft relatively to the mean aerodynamic chord of said integral airlifting surface and the gravity center of said T-tailed deltoid main wing aircraft, thereby further having the crucial impact on the longitudinal dynamic and static stability, yaw and pitch control, as well as the longitudinal trim efficiency of said T-tailed deltoid main wing aircraft.