Abstract: An aircraft includes a fuselage; a propulsion system including a power source and a plurality of vertical thrust electric fans driven by the power source; and a wing extending from the fuselage. The plurality of vertical thrust electric fans are arranged along a length of the wing, the wing including a variable geometry assembly extending along the length of the wing and moveable between a forward thrust position and a vertical thrust position, the variable geometry assembly at least partially covering the plurality of vertical thrust electric fans when in the forward thrust position and at least partially exposing the plurality of vertical thrust electric fans when in the vertical thrust position.

Abstract: An aircraft includes a fuselage; a propulsion system including a power source and a plurality of vertical thrust electric fans driven by the power source; and a wing extending from the fuselage. The plurality of vertical thrust electric fans are arranged along a length of the wing, the wing including a variable geometry assembly moveable generally along a horizontal direction between a forward thrust position and a vertical thrust position, the variable geometry assembly at least partially covering at least one vertical thrust electric fan of the plurality of vertical thrust electric fans when in the forward thrust position and at least partially exposing the at least one vertical thrust electric fan when in the vertical thrust position.

Abstract: An unducted thrust producing system has a rotating element with an axis of rotation and a stationary element. The rotating element includes a plurality of blades each having a blade root proximal to the axis, a blade tip remote from the axis, and a blade span measured between the blade root and the blade tip. The rotating element has a load distribution such that at any location between the blade root and 30% span the value of ?RCu in the air stream is greater than or equal to 60% of the peak ?RCu in the air stream.

Abstract: A method for operating a vertical takeoff and landing aircraft includes modifying a first variable component of a wing associated with a first portion of the plurality of vertical thrust electric fans relative to a second variable component of the wing associated with a second portion of the plurality of vertical thrust electric fans to adjust an exposure ratio of the first portion of the plurality of vertical thrust electric fans relative to the second portion of the plurality of vertical thrust electric fans.

Abstract: An aircraft includes a fuselage; a wing coupled to, and extending from, the fuselage; and a hybrid-electric propulsion system. The hybrid-electric propulsion system includes a power source including a combustion engine and an electric generator; a plurality of vertical thrust electric fans integrated into the wing and oriented to generate thrust along the vertical direction, the plurality of vertical thrust electric fans arranged along a length of the wing and driven by the power source; and a forward thrust propulsor. The forward thrust propulsor it is selectively or permanently mechanically coupled to the combustion engine.

Abstract: An aircraft includes a fuselage; a wing coupled to, and extending from, the fuselage; and a propulsion system. The propulsion system includes a plurality of electric fans integrated into the wing and oriented to generate thrust along a vertical direction, the plurality of electric fans arranged along a length of the wing and including an outer-most electric fan along a transverse direction relative to the fuselage. The outer-most electric fan is at least one of a variable pitch fan or a variable speed fan to provide increased stability to the aircraft.

Abstract: A variable-solidity propeller apparatus, comprising a propeller having at least one rotatable hub carrying at least one row of propeller blades, wherein the propeller has a first configuration in which the propeller has a first average solidity, and a second configuration in which the propeller has a second average solidity which is greater than the first average solidity.

Abstract: An apparatus and method of managing negative incidence of an airfoil are provided. The apparatus includes a row of vane pairs including a first row of main vanes extending radially inwardly from a stationary casing member and spaced circumferentially about a first axial location of the stationary casing member. The apparatus also includes a second row of auxiliary vanes extending radially inwardly from the stationary casing member and spaced circumferentially about a second axial location of the stationary casing member. The apparatus also includes a flow channel defined between a pressure side of each auxiliary vane and a suction side of an adjacent main vane proximate a leading edge of the adjacent main vane.

Abstract: A compressor is provided including a casing, a hub, a flowpath, a plurality of blades defining a plurality of axially extending compressor stages and an endwall treatment formed in the casing on at least two downstream most stages of the plurality of compressor stages. The remaining stages of the plurality of compressor stages located upstream of the at least two downstream most stage are devoid of any endwall treatment. Each of the endwall treatments faces a tip of each blade in the at least two downstream most stages. The tip of each blade and the endwall treatment are configured to move relative to each other. The endwall treatment formed in the casing on at least two downstream most stages of the plurality of compressor stages is configured to extend a stall margin to delay stall due to ice ingestion. A method and engine application are disclosed.

Abstract: An aerodynamic stabilizer assembly for stabilizing an aft fan mounted to a fuselage of an aircraft is presented. The stabilizer assembly includes one or more generally horizontal stabilizers for mounting to a nacelle of the aft fan and the fuselage so as to stabilize the aft fan. Each of the generally horizontal stabilizers includes an inner portion and an outer portion. The inner portions are mounted to a nacelle of the aft fan and the fuselage at a predetermined downward angle with respect to a central axis of the aft fan so as to direct airflow upwards and into the aft fan, the outer portion being mounted to the inner portion.

Abstract: A containment structure comprising an annular structure configured to provide close tolerance to a rotation structure. The containment structure includes a first abradable structure, a second abradable structure, and a shroud that is defined in part by the first abradable structure and in part by the second abradable structure. An annular surface of the shroud is defined by the first abradable structure and by the second abradable structure. The first abradable structure is harder than the second abradable structure.

Abstract: A fan for a gas turbine engine includes: an annular casing; a disk disposed inside the casing and mounted for rotation about an axial centerline, the disk including a row of fan blades extending radially outwardly therefrom; each of the fan blades including an airfoil having circumferentially opposite pressure and suction sides extending radially in span from a root to a tip, and extending axially in chord between spaced-apart leading and trailing edges, with the airfoils defining corresponding flow passages therebetween for pressurizing air; the row including no more than 21 and no less than 13 of the fan blades; and wherein each of the fan blades has a solidity defined by a ratio of the airfoil chord over a circumferential pitch of the fan blades, measured at 60% of a radial distance from the root to the tip, of less than about 1.6.

Abstract: A method of manufacturing a frangible laminate is provided. The method comprises constructing a reinforced polymer matrix, cutting the reinforced polymer matrix into a plurality of laminae, forming a laminate via stacking the plurality of laminae and at least one energy dissipating member, and consolidating the laminate.

Abstract: A variable-cycle compressor includes: an axial-flow compressor, a flowpath downstream of the compressor, and at least one variable-cycle device operable to vary a choked flow capacity of the downstream flowpath. The compressor includes: a rotor having at least one rotor stage including a rotatable disk defining a rotor flowpath surface and an array of axial-flow rotor airfoils extending outward from the flowpath surface; at least one stator stage including a wall defining a stator flowpath surface, and an array of axial-flow stator airfoils extending away from the stator flowpath surface. At least one stage includes splitter airfoils alternating with the rotor or stator airfoils of the corresponding stage. At least one of a chord dimension of the splitter airfoils and a span dimension of the splitter airfoils is less than the corresponding dimension of the airfoils of the at least one stage.

Abstract: A turbofan engine includes: a turbomachinery core; and a low-pressure turbine configured to drive a fan to produce a fan flow, the fan being configured such that at least a portion of the fan flow exits the engine without passing through a turbine. The fan includes: a rotor having at least one rotor stage including axial-flow rotor airfoils, and at least one stator stage including axial-flow stator airfoils. At least one of the rotor or stator stages includes an array of airfoil-shaped splitter airfoils alternating with the rotor or stator airfoils of the corresponding stage. At least one of a chord dimension of the splitter airfoils and a span dimension of the splitter airfoils is less than the corresponding dimension of the airfoils of the at least one stage.

Abstract: The present disclosure is directed to an aerodynamic stabilizer assembly for stabilizing an aft fan mounted to a fuselage of an aircraft. For example, the stabilizer assembly includes one or more generally horizontal stabilizers for mounting to a nacelle of the aft fan and the fuselage so as to stabilize the aft fan. Each of the generally horizontal stabilizers includes an inner portion and an outer portion. As such, the inner portions are mounted to a nacelle of the aft fan and the fuselage at a predetermined downward angle with respect to a central axis of the aft fan so as to direct airflow upwards and into the aft fan, the outer portion being mounted to the inner portion.

Abstract: A frangible airfoil that mitigates adverse conditions associated with release of material resulting from impact damage to the composite blade is provided, the airfoil having provisions for dissipating energy, self-shredding, and predetermined release trajectory.

Abstract: A method and system for a turbofan gas turbine engine system is provided. The gas turbine engine system includes a variable pitch fan (VPF) assembly coupled to a first rotatable shaft and a low pressure compressor LPC coupled to a second rotatable shaft. The LPC including a plurality of variable pitch stator vanes interdigitated with rows of blades of a rotor of the LPC. The gas turbine engine system also includes a speed reduction device coupled to said first rotatable shaft and said second rotatable shaft. The gas turbine engine system further includes a modulating pressure relief valve positioned between an outlet of said LPC and a bypass duct and a controller configured to schedule a position of said plurality of variable pitch stator vanes and said modulating pressure relief valve in response to an operational state of said turbofan gas turbine engine system and a temperature associated with said LPC.

Abstract: An apparatus and method of controlling a multi-stage compressor of a gas turbine engine having a front-block of stages with variable stator vanes (VSVs), a rear block of stages downstream of the front-block, and a bleed air off-take from at least one of the stages. The method includes sensing the pressure of the bleed air from the bleed air off-take and adjusting the position of the VSV for the front-block.

Abstract: An aircraft having a fuselage terminating in an empennage with a tail extending upwardly from the empennage. An engine strut extends from the empennage with an engine mounted to the engine strut and a moveable control surface provided on the engine strut.