Abstract: An impeller for a centrifugal compressor, the impeller rotatable about a central axis, has: an outer hub body including a first material and extending around the central axis, the outer hub body defining a gaspath face extending from an inlet to an outlet, the gaspath face extending radially away from the central axis from the inlet to the outlet; blades protruding from the gaspath face and circumferentially distributed around the central axis; and an inner hub body extending around the central axis, the inner hub body secured to the outer hub body, the outer hub body axially overlapping and extending around the inner hub body, the inner hub body made of a second material being more cold dwell resistant than the first material.

Abstract: A system is provided for an aircraft. This aircraft system includes a gas turbine engine and a sensor system. The gas turbine engine includes an inlet and a compressor section. A flowpath projects radially inward into the gas turbine engine from the inlet and extends through the compressor section. The sensor system includes a plurality of static pressure sensors at least partially within the flowpath. The sensor system is configured to determine a total pressure characteristic within the flowpath using the plurality of static pressure sensors.

Abstract: Methods and systems for determining an engine temperature for a gas turbine engine are provided. An estimated combustor temperature is determined based on at least one operating condition of the gas turbine engine and an estimated vane mass flow. A corrected vane mass flow is determined based on the estimated combustor temperature, the estimated vane mass flow, and a combustor pressure. The corrected vane mass flow is compared to a reference vane mass flow to obtain the mass flow correction factor. When a condition associated with the mass flow correction factor is not satisfied, the estimated combustor temperature is adjusted based on the mass flow correction factor to produce an adjusted combustor temperature; and the mass flow correction factor is updated based on the adjusted combustor temperature. When the condition associated with the mass flow correction factor is satisfied, the estimated combustor temperature is assigned as the engine temperature.

Abstract: An aircraft engine, comprising: a first wall and a second wall defining a gaspath between the first wall and the second wall, the gaspath extending around a central axis, each of the first wall and the second wall having a gaspath side facing the gaspath and an opposed side facing away from the gaspath; struts circumferentially distributed around the central axis, the struts extending across the gaspath, a strut of the struts having an airfoil including a leading edge, a trailing edge, a first end secured to the first wall, and a second end secured to the second wall; and protrusions extending from a baseline surface of the opposed side of the first wall, the protrusions increasing a thickness of the first wall, a protrusion of the protrusions overlapping a location where the leading edge or the trailing edge meets the gaspath side of the first wall.

Abstract: A gas turbine intake has a swirl housing having a tangential inlet fluidly connecting an exhaust conduit, an annular outlet defined around a central axis and fluidly connecting a turbine gas path, a swirl path extending circumferentially around the central axis from the tangential inlet, and vanes located in the swirl housing, the vanes circumferentially interspaced from one another relative the central axis, each vane having a twisted and flat body having a length extending from a leading end to a trailing end, the leading end being oriented mainly circumferentially and axially at the swirl path, the trailing end being oriented mainly axially and radially at the annular outlet, the twisted and flat body twisting between leading and trailing ends around the central axis, around a radial axis perpendicular to the central axis, and around a tangential axis perpendicular to both the central axis and the radial axis.

Abstract: A bearing housing for a bearing having an outer race, the bearing housing comprising: an annular wall extending about an axis and axially between a first end and a second end, the annular wall including: a plurality of holes spaced circumferentially from one another and spaced axially from the first end, the plurality of holes extending through the annular wall toward the axis; and an interior housing surface extending about the axis and defining interior openings of the plurality of holes, the interior housing surface having a cylindrical portion defining a seat for radial engagement with the outer race, the cylindrical portion extending axially from a first location proximate to the first end to at least a second location between the first location and the interior openings.

Abstract: An electric machine system described herein comprises a first and second electric machines configured to drive a load. The first electric machine has a plurality of first rotors driven using electric power having a first phase. The second electric machine has a plurality of second rotors driven using electric power having a second phase. The second phase differs from the first phase. Each of one or more shafts connects a first rotor with a second rotor. The first rotor is coaxial with and axially spaced apart from the second rotor.

Abstract: A borescope plug assembly includes a housing, a plug, and a spring. The housing extends between a first housing end and a second housing end. The housing includes a plug aperture, an internal chamber, and a bayonet interface. The plug aperture is located at the second housing end. The internal chamber extends from the plug aperture toward the first housing end. The plug includes a shaft, a first sealing surface, and at least one tab. The shaft extends between a first shaft end and a second shaft end. The first sealing surface is disposed at the first shaft end. The at least one tab projects radially outward from the shaft. The plug extends through the plug aperture with the second shaft end and the at least one tab disposed within the internal chamber. The spring is positioned within the internal chamber between the first housing end and the at least one tab.

Abstract: A measurement system for an aircraft gas turbine engine includes an instrumentation hub disposed about a rotational axis. The instrumentation hub includes at least one probe. The measurement system further includes a shield hub disposed about the rotational axis and positioned axially adjacent the instrumentation hub. The shield hub includes at least one shield configured to be radially aligned with the at least one probe of the instrumentation hub. The shield hub is rotatable about the rotational axis independent of the instrumentation hub. The at least one shield is axially translatable between a first axial position and a second axial position. The at least one shield in the first axial position is axially aligned with the at least one probe. The at least one shield in the second axial position is axially separated from the at least one probe.

Abstract: A method of forming a component from a part in the green state, including selecting at least one first portion of the part to undergo a different local volume reduction from at least one second portion to obtain the component. The green part is provided with the first portion(s) having a first solid loading and the second portion(s) having a second solid loading different from the first solid loading, then debound and sintered to obtain the component. The different first and second solid loadings produce the different local volume reduction in the first portion(s). The first portion(s) can be selected by determining a resulting final shape obtained from debinding and sintering a green part having a uniform first volumetric proportion of binder, and selecting the first portion(s) requiring a different local deformation than that producing the resulting final shape to obtain a desired final shape.

Abstract: A flow measuring system for one or more oil nozzles of a lubrication system of an aircraft engine comprises an external supply of a testing liquid and a pump fluidly connecting the external supply of the testing liquid to an inlet of the lubrication system via a first conduit. The inlet to the lubrication system is disposed upstream of the one or more oil nozzles. A second conduit fluidly connects an outlet of the lubrication system to the external supply of the testing liquid. The outlet of the lubrication system is disposed downstream of the one or more oil nozzles. A flow measuring device is operable to measure a flow resistance through the one or more oil nozzles.

Abstract: A compressor for an aircraft engine, has: a dual-impeller having: a first impeller having a first inlet and a first outlet located radially outwardly of the first inlet, and a second impeller rotatable with the first impeller, the second impeller having a second inlet and a second outlet located radially outwardly of the second inlet, the first inlet and the second inlet facing opposite axial directions; and first conduits having first conduit inlets and first conduit outlets, the first conduit inlets fluidly connected to the first outlet of the first impeller, the first conduit outlets fluidly connected to the second inlet of the second impeller; and second conduits having second conduits inlets fluidly connected to the second outlet of the second impeller, a second conduit of the second conduits disposed circumferentially between two adjacent first conduits of the first conduits.

Abstract: Ice accumulation and shedding mitigation devices associated with sensor probes extending into a stream of air entering an aircraft engine are provided. An exemplary device comprises a wedge-shaped blade configured to be exposed to the stream of air and disposed upstream of the sensor probe. The wedge-shaped blade has two faces meeting at a leading edge oriented to face the stream of air.

Abstract: A secondary air system (SAS) of an aircraft engine that produces secondary airflow from a source of secondary air includes a hollow strut and one or more SAS feed pipes upstream thereof. The hollow strut extends radially through the main gas path of the engine and defines therein a strut conduit extending between a strut inlet and a strut outlet at opposite ends of the hollow strut. The strut outlet is in fluid flow communication with a buffer cavity for feeding the secondary airflow to the engine core. The SAS feed pipe includes an inlet receiving the secondary airflow from the source of secondary air, and an outlet in fluid flow communication with the strut inlet to feed the secondary airflow into the strut conduit. The SAS feed pipe has a sonic orifice therein, between the inlet and the outlet thereof.

Abstract: A centrifugal compressor, has: an impeller; and a housing including: a shroud extending between a first end and a second end; a structural member having an outer end securable to a casing of the gas turbine engine, an inner end of the structural member intersecting the rear side of the shroud; and a reinforced region at the location where the structural member and the rear side of the shroud intersect, a thickness of the reinforced region in a direction normal to the gaspath side greater than a nominal thickness of the shroud, the reinforced region defining a curved surface extending from a first location on the structural member to a second location on the rear side of the shroud, a portion of the curved surface having a radius that increases from a first radius to a second radius at the second location.

Abstract: A tool assembly is provided for removing a component from a carrier. The component circumscribes and is mounted on the carrier. The tool assembly includes a tool head, an adaptor and an actuator. The tool head is configured to couple to the component. The adaptor extends longitudinally along a centerline between an adaptor first end and an adaptor second end. The adaptor is attachable to the tool head at the adaptor first end by a first quick coupler. The actuator includes a housing and a ram. The housing is attachable to the adaptor at the adaptor second end by a second quick coupler. The ram extends longitudinally along the centerline within the adaptor and the tool head to a ram distal end. The ram distal end is configured to engage the carrier.

Abstract: A fuel nozzle assembly comprising an annular slot surrounding a fuel nozzle, the annular slot having gas passages for feeding a gas into the slot and against an opposing wall of the slot. A method of operating a gas turbine engine including directing a gas flow into and across the slot against an opposing wall of the slot to generate a circulating gas flow filling the slot, the gas flow passing into the slot through one or more gas outlets within the slot and thereafter said gas flow exiting the slot into the combustion chamber, the gas outlets spaced away from the closed end of the slot. A gas turbine engine comprising a slot formed in a fuel nozzle assembly, the slot having one or more gas passages extending through a wall of the slot and feeding a gas into the slot against a another wall of the slot.

Abstract: A method of repair for a metallic part of an aircraft engine includes detecting a defect inside a bore of the metallic part wherein the defect represents a departure from an intended geometry of the bore, the bore having a diameter and defining a longitudinal axis, and wherein the defect is located within the bore at a depth of at least greater than one diameter along the longitudinal axis. The method also includes measuring a geometry of the defect, preparing a patch with a complementary geometry to fill the geometry of the defect, placing the patch in the bore with the complementary geometry of the patch seated against the geometry of the defect, directing a welding beam from outside the bore, through the bore and onto the patch to weld the patch to the bore, and removing a portion of the patch to provide the intended geometry for the bore.

Abstract: A hybrid electric propulsion (HEP) system can include a heat engine torque sensor connected between a heat engine and a combining gear box to sense a heat motor input torque input to the combining gear box, an electric motor torque sensor connected between an electric motor and the combining gear box to sense an electric motor input torque input to the combining gear box, and a combining gear box torque sensor connected to an output of the combining gearbox. The system can include a HEP controller operatively connected to each of the heat engine torque sensor, the electric motor torque sensor, and the combining gear box torque sensor to receive one or more torque signals therefrom. The controller can be configured to output one or more output signals as a function of the signals from each of the heat engine torque sensor, the electric motor torque sensor, and the combining gear box torque sensor.

Abstract: An aircraft engine has: a compressor section having a compressor rotor rotatable about a central axis; a diffuser downstream of the compressor rotor, the diffuser including a diffuser ring extending circumferentially around the central axis; a bearing housing secured to the diffuser ring, the bearing housing contained within a volume located radially inwardly of the diffuser ring; and an air manifold secured to the diffuser ring, the air manifold defining inlets in fluid flow communication with the compressor section and an outlet in fluid flow communication with the volume.