Abstract: The present disclosure is directed to a gas turbine engine defining a longitudinal direction, a radial direction, and a circumferential direction, and an upstream end and a downstream end along the longitudinal direction. The gas turbine engine includes a turbine section, a gearbox proximate to the turbine section, and a driveshaft. The turbine section includes a first rotating component interdigitated with a second rotating component along the longitudinal direction. The first rotating component includes an outer shroud defining a plurality of outer shroud airfoils extended inward of the outer shroud along the radial direction and one or more connecting airfoils coupling the outer shroud to a radially extended rotor. The second rotating component includes an inner shroud defining a plurality of inner shroud airfoils extended outward of the inner shroud along the radial direction. The second rotating component is coupled to an input shaft connected to an input gear of the gearbox.

Abstract: A gas turbine engine having a forward thrust mode and a reverse thrust mode is provided. The gas turbine engine includes a variable pitch fan configured for generating forward thrust in the forward thrust mode of the engine and reverse thrust in the reverse thrust mode of the engine. The engine also includes a fan cowl surrounding the variable pitch fan, wherein the fan cowl forms a bypass duct for airflow generated by the fan. The fan cowl includes an aft edge that defines a physical flow area of the bypass duct, and a deflection device configured for deflecting airflow near the aft edge, wherein the deflection device is configured for operation in the reverse thrust mode of the engine. The physical flow area of the bypass duct at the aft edge remains the same in the forward thrust mode of the engine and in the reverse thrust mode of the engine.

Abstract: The present disclosure is directed to a gas turbine engine including a turbine rotor, a turbine frame at least partially surrounding the turbine rotor, and an outer diameter seal assembly. The turbine rotor includes an inner shroud, an outer shroud, and at least one connecting airfoil coupling the inner shroud and the outer shroud. The outer shroud includes a plurality of outer shroud airfoils extended inward along a radial direction. The outer diameter seal assembly includes a sliding portion disposed between the turbine frame and the outer shroud of the turbine rotor. The outer diameter seal assembly defines a secondary tooth at the outer shroud radially inward of a longitudinal face of the sliding portion, and a primary tooth defined axially adjacent to a radial face of the sliding portion.

Abstract: A gas turbine engine includes a core and a tie shaft. The tie shaft is rotatable about an axial direction of the gas turbine engine by the core of the gas turbine engine. The gas turbine engine additionally includes a modular fan having a plurality of fan blades and a frame. The plurality fan blades are attached to the frame and the frame is slidably received on the tie shaft of the gas turbine engine. The modular fan additionally includes an attachment member removably attaching the frame to the tie shaft of the gas turbine engine to removably install the modular fan in the gas turbine engine.

Abstract: An aircraft includes a fuselage, a forward wing assembly, and aft wing assembly, and a propulsion system. The propulsion system includes a port forward propulsor and a starboard forward propulsor, each of which rotatable between a forward thrust position and a vertical thrust position and together defining a maximum forward thrust capability. The propulsion system also includes a port aft propulsor and a starboard aft propulsor, each of which also rotatable between a forward thrust position and a vertical thrust position, and together defining a maximum aft thrust capability. The maximum forward thrust capability is different than the maximum aft thrust capability to achieve certain efficiencies.

Abstract: The variable pitch propeller assembly includes a hub. The variable pitch propeller assembly also includes a plurality of propeller blade assemblies spaced circumferentially about the hub. Each of the plurality of propeller blade assemblies configured to rotate a respective propeller blade. The variable pitch propeller assembly also includes a hydraulic fluid port assembly integrally formed and including at least three hydraulic fluid ports configured to receive respective flows of hydraulic fluid from a stationary hydraulic fluid transfer sleeve. The variable pitch propeller assembly also includes a pitch actuator assembly coupled in flow communication with at least three hydraulic fluid ports through respective hydraulic fluid transfer tubes. The pitch actuator coupled to the plurality of propeller blade assemblies to selectively control a pitch of the propeller blades. The pitch actuator assembly includes a travel stop configured to limit a rotation of at least one of the pitch actuator assemblies.

Abstract: A method for operating a propulsion system of an aircraft includes moving a plurality of forward and aft propulsors to a vertical thrust position. While in the vertical thrust positions, the method also includes providing a first forward to aft ratio of electric power to the plurality of forward and aft propulsors. The method also includes moving the plurality of forward and aft propulsors to a forward thrust position. While in the forward thrust positions, the method also includes providing a second forward to aft ratio of electric power to the plurality of forward and aft propulsors. The first forward to aft ratio of electric power is different than the second forward to aft ratio of electric power to provide certain efficiencies for the aircraft.

Abstract: An aircraft includes a fuselage and a wing assembly attached to or formed integrally with the fuselage. The aircraft also includes a propulsion system having a port propulsor and a starboard propulsor. The port and starboard propulsors are each attached to the wing assembly on opposing sides of the fuselage and are rotatable between a forward thrust position and a vertical thrust position. The propulsion system also includes a supplemental propulsor mounted to the fuselage to provide certain efficiencies for the aircraft.

Abstract: The present application relates to a frictional damper, a frictional damper assembly and method for installing the frictional damper. The frictional damper comprises a split ring; and a disk spring positioned against the split ring and tensioned by the split ring in an installed state.

Abstract: A gas turbine engine includes a core turbine engine and a fan mechanically coupled to the core turbine engine. The fan includes a plurality of fan blades, each fan blade defining a base and an inner end along a radial direction of the gas turbine engine. The fan also includes a hub covering the base of each of the plurality of fan blades. Further, the fan includes one or more bearings for supporting rotation of the plurality of fan blades. The one or more bearings define a fan bearing radius along a radial direction of the gas turbine engine. Similarly, the hub defines a hub radius along the radial direction of the gas turbine engine. The ratio of the hub radius to the fan bearing radius is less than about three, providing for desired packaging of the various components within the fan of the gas turbine engine.

Abstract: The present disclosure is directed to an electric machine defining a longitudinal direction, a radial direction, and a circumferential direction, and an axial centerline defined along the longitudinal direction. The electric machine includes a rotor assembly that includes a plurality of carriers arranged along the circumferential direction. Each pair of carriers defines a carrier gap therebetween along the circumferential direction, and each carrier includes a rotor magnet. The rotor assembly further includes an outer ring radially outward of and surrounding the plurality of carriers along the circumferential direction, the outer ring defining a unitary structure.

Abstract: A turbomachine and method for operating a turbomachine comprising a first rotatable component and a second rotatable component each defining a rotatable speed mechanically independent of one another, and an electric machine electrically coupled to the first rotatable component and the second rotatable component such that a load level relative to the first rotatable component and the second rotatable component is adjustable is generally provided.

Abstract: The present disclosure is directed to a gas turbine engine defining a radial direction, a circumferential direction, an axial centerline along a longitudinal direction, and wherein the gas turbine engine defines an upstream end and a downstream end along the longitudinal direction, and wherein the gas turbine engine defines a core flowpath extended generally along the longitudinal direction. The gas turbine engine includes a turbine frame defined around the axial centerline, the turbine frame comprising a first bearing surface disposed inward along the radial direction. The gas turbine engine further includes a turbine rotor assembly including a bearing assembly coupled to the first bearing surface of the turbine frame and the turbine rotor assembly. The turbine rotor assembly further includes a first turbine rotor disposed upstream of the turbine frame and a second turbine rotor disposed downstream of the turbine frame.

Abstract: A variable pitch fan for a propulsion device is provided. The variable pitch fan includes a plurality of fan blades coupled to a disk and a rotatable front hub covering the disk. Each fan blade is rotatable about a pitch axis to vary a pitch of the fan blade. The pitch is variable within a pitch range that is at least about 80° to about 130°. Each fan blade extends radially outward from the disk along a span from a root to a tip. A portion of the span adjacent the root defines a root span region, a portion of the span adjacent the tip defines a tip span region. A solidity of the variable pitch fan is at least 1.0 in the root span region.

Abstract: A gas turbine engine including a first rotor assembly is generally provided. The first rotor assembly includes outer drum and an outer drum airfoil. The outer drum airfoil is coupled to the outer drum and extended inward along a radial direction. A damper structure is coupled to one or more of the outer drum or the outer drum airfoil.

Abstract: An aircraft includes a fuselage, a forward wing assembly, and aft wing assembly, and a propulsion system. The propulsion system includes a first primary thrust propulsor and a first secondary thrust propulsor, the first primary thrust propulsor being different than the first secondary thrust propulsor. Both the first primary thrust propulsor and the first secondary thrust propulsor are mounted to the same one of: a starboard side of the aft wing assembly, a port side of the aft wing assembly, a starboard side of the forward wing assembly, or a port side of the forward wing assembly.

Abstract: A turbomachine includes a spool and a turbine section. The turbine section includes a turbine center frame and a turbine, with the turbine including a first plurality of turbine rotor blades and a second plurality of turbine rotor blades. The first plurality of turbine rotor blades and second plurality of turbine rotor blades are alternatingly spaced along the axial direction. The turbomachine also includes a gearbox aligned with, or positioned aft of, a midpoint of the turbine. The gearbox includes a first gear coupled to the first plurality of rotor blades, a second gear coupled to the second plurality of rotor blades, and a third gear coupled to the turbine center frame. The turbomachine also includes a support member, the first plurality of turbine rotor blades coupled to the spool through the support member, the support member extending aft of the gearbox.

Abstract: A turbomachine includes a spool; and a turbine section including a turbine and a turbine center frame. The turbine includes a first plurality of turbine rotor blades and a second plurality of turbine rotor blades alternatingly spaced along an axial direction and rotatable with one another. The turbomachine also includes a first support member, the first plurality of turbine rotor blades coupled to the spool through the first support member; a second support member, the second plurality of turbine rotor blades supported by the second support member; and a bearing assembly including a first bearing and a second bearing, the first bearing and the second bearing each rotatably supporting the second support member and each being supported by the turbine center frame.

Abstract: The present disclosure is directed to a gas turbine engine including a torque frame. The torque frame includes an inner shroud defined circumferentially around the axial centerline, an outer shroud surrounding the inner shroud and defined circumferentially around the axial centerline, and a structural member extended along the radial direction and coupled to the inner shroud and the outer shroud. The torque frame is configured to rotate around the axial centerline.

Abstract: A turbomachine includes a turbine section including a turbine center frame and a turbine, the turbine including a plurality of low-speed turbine rotor blades and a plurality of high-speed turbine rotor blades alternatingly spaced along the axial direction. The plurality of low-speed turbine rotor blades each extend between a radially inner end and a radially outer end. At least two of the plurality of low-speed turbine rotor blades are spaced from one another along the axial direction and coupled to one another at the radially outer ends. The turbomachine also includes a gearbox aligned with, or positioned forward of, a midpoint of the turbine. The gearbox includes a first gear coupled to the plurality of low-speed turbine rotor blades, a second gear coupled to the plurality of high-speed turbine rotor blades, and a third gear coupled to the turbine center frame.