An aircraft having a fuselage with a nose and a flat tail at opposite ends and a pair of wings extending therefrom. A pair of nacelles are detachably connected to the top of respective ones of the wings to be spaced from the fuselage to establish an air flow space therebetween. Each wing-mounted nacelle includes a plurality of fans, a corresponding plurality of electric motors to drive the fans, and dividers that separate the fans from one another. Each wing-mounted nacelle also includes a pair of rotatable air inlet slats at an air intake end and a pair of rotatable air exhaust flaps at an air exhaust end that are rotated relative to one another to control horizontal propulsive thrust, thrust vectoring and thrust reversing of the aircraft. A third nacelle is mounted on top of the flat tail of the fuselage between a pair of horizontal turbo generators.

An aircraft having a fuselage with a nose and a flat tail at opposite ends and a pair of wings extending therefrom. A pair of nacelles are detachably connected to the top of respective ones of the wings to be spaced from the fuselage to establish an air flow space therebetween. Each wing-mounted nacelle includes a plurality of fans, a corresponding plurality of electric motors to drive the fans, and dividers that separate the fans from one another. Each wing-mounted nacelle also includes a pair of rotatable air inlet slats at an air intake end and a pair of rotatable air exhaust flaps at an air exhaust end that are rotated relative to one another to control horizontal propulsive thrust, thrust vectoring and thrust reversing of the aircraft. A third nacelle is mounted on top of the flat tail of the fuselage between a pair of horizontal turbo generators.

An aircraft (41) including a fuselage (14) having a skin (15) and extending along a longitudinal axis (39) from a front end to a rear end (17) of the aircraft, and an engine (30) including an air intake (31) forming an opening in the skin (15) and an exhaust (32) forming another opening in the skin (15). The engine is in a rear fuselage section, in which the exhaust (32) is situated ahead of the air intake (31) along the longitudinal direction (39).

An aircraft (41) including a fuselage (14) having a skin (15) and extending along a longitudinal axis (39) from a front end to a rear end (17) of the aircraft, and an engine (30) including an air intake (31) forming an opening in the skin (15) and an exhaust (32) forming another opening in the skin (15). The engine is in a rear fuselage section, in which the exhaust (32) is situated ahead of the air intake (31) along the longitudinal direction (39).

Apparatuses and systems are provided herein for unducted propulsion systems. The system includes an aft housing for low drag for high subsonic sustained flight. A plurality of blades are affixed to the aft housing, wherein the housing defines a flowpath curve extending from the axial extent of the aft blade root to the aft end of the aft housing. The flowpath curve is described by an axial direction parallel to an axis of rotation and a radius from the axis of rotation. The flowpath curve includes first point having a first radius where the radius reaches a maximum aft of the aft blade root and a second point forward of the first point having a second radius where the radius stops decreasing. The ratio of the first radius to the second radius is greater than or equal to 1.081.

Flexible aft cowls are disclosed. In some examples, an aircraft engine having a flexible aft cowl is disclosed. In some examples, the aircraft engine comprises an aft cowl having a flexible portion defining a throat area adjacent an engine core nozzle of the aircraft engine. In some examples, the flexible portion to move radially between a first radial position in response to pressure within a nacelle not exceeding a pressure threshold and a second radial position in response to pressure within the nacelle exceeding the pressure threshold. In some examples, the throat area defined by the flexible portion is greater when the flexible portion is in the second radial position than when the flexible portion is in the first radial position.

Flexible aft cowls are disclosed. In some examples, an aircraft engine having a flexible aft cowl is disclosed. In some examples, the aircraft engine comprises an aft cowl having a flexible portion defining a throat area adjacent an engine core nozzle of the aircraft engine. In some examples, the flexible portion to move radially between a first radial position in response to pressure within a nacelle not exceeding a pressure threshold and a second radial position in response to pressure within the nacelle exceeding the pressure threshold. In some examples, the throat area defined by the flexible portion is greater when the flexible portion is in the second radial position than when the flexible portion is in the first radial position.

A variable area exhaust nozzle defining an actual area ratio for a gas turbine engine that includes a shroud assembly having a fixed shroud and an adjustable cowl, an adjustable plug, a nozzle adjustment assembly, and a controller configured to receive data indicative of an operating speed of the gas turbine engine; determine a target area ratio based at least in part on received data indicative of the operating speed of the gas turbine engine; and operate the nozzle adjustment assembly to selectively adjust at least one of the adjustable cowl or the adjustable plug such that the actual area ratio is substantially equivalent to the target area ratio.

A variable area exhaust nozzle defining an actual area ratio for a gas turbine engine that includes a shroud assembly having a fixed shroud and an adjustable cowl, an adjustable plug, a nozzle adjustment assembly, and a controller configured to receive data indicative of an operating speed of the gas turbine engine; determine a target area ratio based at least in part on received data indicative of the operating speed of the gas turbine engine; and operate the nozzle adjustment assembly to selectively adjust at least one of the adjustable cowl or the adjustable plug such that the actual area ratio is substantially equivalent to the target area ratio.

An aircraft includes a fuselage extending between a forward end and an aft end; a propulsor mounted to the fuselage at the aft end of the fuselage, the propulsor comprising an outer nacelle, the outer nacelle defining an inlet to the propulsor; and a deployable assembly attached to at least one of the fuselage or the outer nacelle and moveable between a stowed position and an engaged position. The deployable assembly alters an airflow towards the propulsor or into the propulsor through the inlet defined by the outer nacelle when in the engaged position. The propulsor further comprises a tail cone, wherein the outer nacelle defines an exhaust with the tail cone, and wherein the plurality of nacelle panels are movable generally along the axial centerline to a position at least partially aft of the exhaust of the outer nacelle when in the engaged position.