Abstract: A gas turbine engine comprises a turbine, a combustor fluidly coupled to the turbine, and a cooling air system. The turbine includes including a turbine rotor having a shaft mounted for rotation about an axis of the gas turbine engine and a set of turbine blades coupled to the turbine rotor for rotation therewith. The combustor includes an outer combustor case and an inner combustor case that cooperate to define a combustion chamber. The cooling air system is configured to cool the turbine using air form the combustion chamber of the combustor.

Abstract: An example hybrid aircraft propulsion system includes one or more power units configured to output electrical energy onto one or more electrical busses; a plurality of propulsors; and a plurality of electrical machines, each respective electrical machine configured to drive a respective propulsor of the plurality of propulsors using electrical energy received from at least one of the one or more electrical busses.

Abstract: A system including a turbine engine configured to generate rotor power and produce an engine air flow. The system is configured to provide rotor power to one of more shaft-driven lift fans to generate a first thrust on an aircraft body and provide a gas flow to one or more gas-driven lift fans to generate a second thrust on the aircraft body. The gas flow may be at least a portion of the engine air flow produced by the turbine engine. The turbine engine may be configured to exhaust another portion of the engine air flow through a jet nozzle to generate an engine thrust. In examples, the system includes at least a second turbine engine. The one of more shaft-driven lift fans and/or one of more gas-driven lift fans be powered by the turbine engine, the second turbine engine, or both the turbine engine and the second turbine engine.

Abstract: Airfoils and methods of cooling an airfoil are provided. The airfoil may comprise a spar; a coversheet on the spar; and a dual feed circuit between the spar and the coversheet. The dual feed circuit may include a first dam, a second dam spaced apart from the first dam along the chord axis of the spar, a first inlet disposed adjacent to the first dam, a second inlet disposed adjacent to the second dam, a circuit outlet disposed between the first inlet and the second inlet, and a plurality of diamond and/or hexagonal pedestals disposed on an outer surface of the spar. The diamond and/or hexagonal pedestals may form a plurality of cooling channels between the first inlet, the second inlet, and the circuit outlet. There may be no other circuit inlets are located between the first inlet and the second inlet.

Abstract: A starter generator located within a sump region of a turbofan engine and coupled to an adapter shaft. The adapter shaft rotationally coupled to the high pressure shaft, forward of a high pressure shaft bearing, and secured by a spanner nut. The engine makes use of two pluralities of electrical conductors, the first extends through an electrical conduit defined by a forward strut extending from the sump region to the outward casing, the second extends axially away from the electric starter. Each of the first plurality of electrical conductors makes reversible contact with a respective one of the second plurality of electrical conductors via an elbow/pin connector, producing a tight turn in area of limited space.

Abstract: An article that includes a substrate; a first layer including yttria and zirconia or hafnia, where the first layer has a columnar microstructure and includes predominately the zirconia or hafnia; a second layer on the first layer, the second layer including zirconia or hafnia, ytterbia, samaria, and at least one of lutetia, scandia, ceria, neodymia, europia, and gadolinia, where the second layer includes predominately zirconia or hafnia, and where the second layer has a columnar microstructure; and a third layer on the second layer, the third layer including zirconia or hafnia, ytterbia, samaria, and a rare earth oxide including at least one of lutetia, scandia, ceria, neodymia, europia, and gadolinia, where the third layer has a dense microstructure and has a lower porosity than the second layer.

Abstract: A rotating machine including a thrust bearing configured to receive an axial thrust exerted by a rotor. The thrust bearing may be configured to transfer the axial thrust from the rotor to a housing or other structural component of the rotating machine using a plurality of ball bearings. The rotating machine includes a magnetic apparatus configured to cause the rotating machine to exert an axial force on the thrust bearing in the direction of the axial thrust of the rotor, such that the magnetic apparatus loads the ball bearings in the direction of the axial thrust. The magnetic apparatus may be configured to generate a magnetic field causing a first magnetic component of the magnetic apparatus to repel or attract a second magnetic component of the apparatus. The first magnetic component may be configured to rotate relative to the second magnetic component.

Abstract: An inlet duct for a gas turbine engine includes a particle separator, a scavenge duct, and a layer of material having a low coefficient of restitution. The particle separator including an outer wall spaced, an inner wall, and a splitter located radially between the outer wall and the inner wall. The scavenge duct is coupled with particle separator. The layer of material is located on at least one of the outer wall, the splitter, and the scavenge duct.

Abstract: A gas turbine engine comprises an engine core and an electric fan array. The engine core includes a compressor, a combustor, and a turbine. The compressor compresses and delivers air to the combustor. The combustor mixes fuel with the compressed air received from the compressor and ignites the fuel. The hot, high-pressure products of the combustion reaction in the combustor are directed into the turbine to cause the turbine to rotate about an axis and drive the compressor. The electric fan array may include at least two non-concentric fans having parallel shafts.

Abstract: A vane adjustment assembly includes a plurality of vanes, an annular ring coupled to the vanes, and a ring adjustment assembly. The ring adjustment assembly includes a shim plate having a first shim surface removably arranged on an axially facing surface of the annular ring, a carrier plate having a first carrier surface removably arranged on a second shim surface of the shim plate opposite the first shim surface, and a roller pin coupled to a second carrier surface of the carrier plate opposite the first carrier surface. The shim plate is sized so as to locate the roller pin at a predetermined distance from the annular ring so as to adjust a position of the plurality of variable vanes relative to the roller pin.

Abstract: In some examples, an article may include a substrate and a coating system on the substrate. The coating system may include a layer comprising a plurality of voids, wherein respective voids of the plurality of voids define respective void volumes; and a nucleating agent within at least some of the respective void volumes of the layer, wherein the nucleating agent is configured to induce crystallization of the molten CMAS. The coating system may include an environmental barrier coating, thermal barrier coating, and/or abradable coating.

Abstract: A guide vane assembly includes a fan case, a vane, and a retention ring. The fan case extends circumferentially partway about an axis. The vane extends radially inward away from the fan case and is coupled to the fan case. The retention ring extends circumferentially partway about the axis and is coupled with the fan case and supports the vane.

Abstract: Systems and methods to increase the recharge rate of a supplemental cooling system are provided. The system may include a primary cooling system configured to cool a thermal load, a supplemental cooling system, and a thermoelectric cooling apparatus. The thermoelectric cooling apparatus may assist the primary cooling system in recharging the supplemental cooling system in response to the supplemental cooling system operating in a recharge state, to the availability of electrical capacity, and to one or more operating parameters of the primary cooling system falling outside a predetermined range, wherein the operating parameter affects a cooling capacity of the primary cooling system.

Abstract: An additive manufacturing technique includes depositing, via a filament delivery device, a filament onto a surface of a substrate. The filament includes a binder and a high entropy alloy powder. The technique also includes sacrificing the binder to form a preform and sintering the preform to form a component.

Abstract: A method of fabricating cooling features on a CMC component may comprise compressing a fabric preform within tooling including holes and/or recesses facing the fabric preform. During the compression, portions of the fabric preform are pushed into the holes and/or recesses. Gases are delivered through the tooling to deposit a matrix material on exposed surfaces of the fabric preform while the fabric preform is being compressed. The matrix material builds up on the portions of the fabric preform pushed into the holes and/or recesses, and a rigidized preform with surface protrusions is formed. The tooling is removed, and the rigidized preform is densified, thereby forming a CMC component including raised surface features.

Abstract: In some examples, a method comprising: controlling a first ratio of a first liquid to a second liquid to form a first suspension comprising a powder and a first carrier liquid composition comprising at least one of the first liquid or the second liquid; directing the first suspension comprising the first carrier liquid and the powder to a plume of a thermal spray device; forming a first portion of a coating comprising the powder on a substrate from the first suspension; controlling a second ratio of the first liquid to the second liquid to form a second suspension comprising a second carrier liquid composition and the powder; directing the second suspension comprising the second carrier liquid composition and the powder to the plume of the thermal spray device; and forming a second portion of the coating comprising the powder on the substrate from the second suspension.

Abstract: A compressor adapted for use in for a gas turbine engine includes a diffuser and a housing. The diffuser is arranged circumferentially around an axis and includes a fore plate, an aft plate spaced apart axially from the fore plate to define a flow path therebetween, and a plurality of vanes that extend between the fore plate and the aft plate. The housing is arranged circumferentially about the axis and located adjacent the diffuser.

Abstract: A propulsion system includes two gas turbine engines and an air-provisioning system. The air-provisioning system includes a first ejector, a second ejector, a plenum fluidically connected with the first ejector and the second ejector, and a first propulsor. The air-provisioning system is configured to bleed and mix air from each gas turbine engine in the ejectors so as to provide selectively a flow of plenum air from the plenum to the first propulsor at a desired pressure and a desired flow rate to power the first propulsor.

Abstract: A heat transfer system for controlling two or more heat loads, including a high transient heat load, is provided. The heat transfer system may include sensible-heat thermal energy storage. A method of transferring heat from two or more heat loads to an ambient environment is further provided.

Abstract: An additively manufactured component that includes a tool with a region having a plurality of overlying metal layers each derived from a metal powder filament. The region has a predetermined yield point selected based on an operation to be performed with the tool.