Propulsion system for a V/STOL airplane

A propulsion system for a vertical and short takeoff and landing airplane, comprising;

• a nacelle having an upper surface and a lower surface forming an upper surface and a lower surface of an airfoil, respectively;
• the nacelle having a generally rectangular inlet and outlet;
• a turbofan engine, including a fan and a turbine engine, both mounted in the nacelle;
• an upper flap pivotally secured adjacent the trailing edge of the nacelle and forming a part of the airfoil upper surface, the upper flap having a pair of vanes secured between the upper surface of the upper flap and the trailing edge of the nacelle upper surface;
• the vanes being secured to the upper flap and pivotal with the upper flap, the vanes being spaced vertically apart from each other and vertically from the upper surface of the upper flap, defining an upper slot and an intermediate slot, the intermediate slot discharging a portion of the fan exhaust, the upper flap being pivotal between a horizontal flight position generally aligned with the nacelle upper surface, and a vertical flight position pointing generally downward for vectoring fan and engine exhaust downward;
• a shroud extending from the rear of the turbine engine to the upper slot for discharging the engine exhaust separate from the fan exhaust;
• a lower flap pivotally secured to the nacelle lower surface and forming a part of the airfoil lower surface, the lower flap being pivotal between a horizontal flight position generally aligned with the nacelle lower surface and a vertical flight position, pointing generally downward to vector the fan exhaust downward;
• and
• an intermediate flap pivotally secured to the nacelle and pivotal between a horizontal flight position to the rear of the lower flap and forming a part of the airfoil lower surface, and a vertical flight position below the upper flap, pointing generally downward and forming a part of the airfoil upper surface;
• in the vertical flight position, the upper flap and intermediate flap being positioned with a lower slot between their trailing and leading edges, respectively, for discharging a portion of the fan exhaust;
• in the horizontal flight position, the upper and intermediate flaps defining a horizontal flight main thrust nozzle;
• in the vertical flight position, the lower and intermediate flaps defining a vertical flight main thrust nozzle;
• normally, the sum of the areas of the upper slot, intermediate slot, and horizontal flight main thrust nozzle being substantially equal to the sum of the areas of the upper slot, intermediate slot, lower slot and vertical flight main thrust nozzle, and also equal to the sum of the areas of all the slots and the spaces between the flaps in all transition positions, and the flaps also may be actuated such that the sum of the areas of the slots and the nozzles vary according to a predetermined schedule in any flight position from horizontal to vertical.