Abstract: A method of operating a variable guide vane assembly of an aircraft engine, the variable guide vane assembly including guide vanes rotatable about respective spanwise axes and circumferentially distributed about a central axis, the method comprising: obtaining a target exit flow angle defined between a direction of a flow exiting the guide vanes and the central axis; predicting an exit flow angle as a function of at least a geometric angle, the exit flow angle defined between the direction of the flow exiting the guide vanes and the central axis, the geometric angle defined between the guide vanes and the central axis; and when a difference between the exit flow angle and the target exit flow angle is above a threshold, modulating the guide vanes to modify the geometric angle until the difference between the exit flow angle and the target exit flow angle is at or below the threshold.

Abstract: A multi-engine system for an aircraft, has: a first engine having a first output shaft, a first core shaft, and a first electric machine drivingly engaged by the first output shaft or the first core shaft; a second engine having a second output shaft, a second core shaft, and a second electric machine drivingly engaged to the second core shaft; a reduction gearbox drivingly engaged by the first output shaft and by the second output shaft for driving a common load; and a transmission path between the first engine and the second engine, the transmission path being independent from the reduction gearbox and being one or more of: a torque-transfer connection between the second core shaft and the first core shaft or the first output shaft via a coupling gearbox, and an electrical connection between the generator and the electric motor to transmit electrical power to the electric motor.

Abstract: The torque transfer assembly can have a torque shaft rotatable around a rotation axis, the torque shaft having a first end and a second end opposite the first end along the rotation axis, a first reference feature at an intermediary location between the first end and the second end, and a sun gear integrated to the torque shaft, at the first end, the second end has a first external diameter, and the sun gear having a second external diameter greater than the first external diameter; and a reference tube having a fixed end secured to the torque shaft adjacent the second end, a free end having a second reference feature adjacent the first reference feature, the reference tube extending around the torque shaft, the reference tube having an internal diameter, the internal diameter being between the first external diameter and the second external diameter.

Abstract: A rotary engine, has: an outer body defining a rotor cavity; a rotor rotatable within the rotor cavity and in sealing engagement with walls of the outer body and defining at least one chamber of variable volume in the rotor cavity; a pilot subchamber defined by the outer body, the pilot subchamber having an outlet in fluid flow communication with the rotor cavity; and a fuel injector having a tip in communication with the rotor cavity at a location spaced apart from the outlet of the pilot subchamber, the tip of the fuel injector having: a first outlet in fluid communication with the rotor cavity independently of the pilot subchamber; and a second outlet in fluid communication with the rotor cavity through the pilot subchamber.

Abstract: A sensor signal produced by a sensor as a feedback device rotates with a propeller about an axis and moves along the axis with adjustment of a blade angle of the propeller is received, the sensor signal indicative of a rotational speed and of the blade angle of the propeller. From the sensor signal, it is determined whether the rotational speed is within a predetermined range of a reference speed and an expected change in the blade angle has occurred in response to a command to adjust the blade angle to maintain the rotational speed at the reference speed. In response to determining that the rotational speed is within the predetermined range of the reference speed and the expected change in the blade angle has failed to occur in response to the command, inoperable movement of the feedback device along the axis is determined and an alert is output.

Abstract: An electric machine system disclosed herein comprises first and second electric machines configured to drive a load. The first electric machine has a plurality of first rotors. The second electric machine has a plurality of second rotors. At least one of the second rotors is indexed relative to a respective one of the first rotors to, in use, provide a torque phase offset between the first and second electric machines. A shaft is coupled to the load and connects the respective one of the first rotors with the at least one of the second rotors. The respective one of the first rotors is coaxial with and axially spaced apart from the at least one of the second rotors.

Abstract: Electromagnetic chip detectors and associated methods of detecting a metallic chip in engine fluid of an engine are provided. The method comprises supplying an electric current to a circuit extending between a first node and a second node to magnetize both a first electrically conductive terminal and a second electrically conductive terminal spaced apart from each other to define a chip-receiving gap therebetween, and detecting a change in resistance across the first node and the second node. The change in resistance is indicative of a capture of the chip by the electromagnetic chip detector. The chip electrically connects the first electrically conductive terminal to the second electrically conductive terminal. The first electrically conductive terminal is electrically connected to the first node. The second electrically conductive terminal is electrically connected to the second node.

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: 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 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: 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 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 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.