Abstract: A method of controlling a multi-engine aircraft includes receiving input for commanded thrust and modifying the commanded thrust using a model of an incumbent powerplant to generate a modified commanded thrust for matching aircraft performance with a new powerplant to the aircraft performance with the incumbent powerplant. The method includes applying the modified commanded thrust to the new powerplant.

Abstract: There is provided an exhaust mixer arrangement for a turbofan engine having a bypass passage for channelling a bypass flow and a core passage for channelling a core flow around a central axis. The exhaust mixer arrangement comprises a mixer body mounted for rotation about the central axis. The mixer body has an annular wall extending around the central axis. The annular wall defines a plurality of circumferentially distributed alternating inner and outer lobes, with each inner lobe protruding into the core passage, and each outer lobe protruding into the annular bypass passage. A driving unit is operatively connected to the mixer body for selectively driving the mixer body in rotation about the central axis. A controller is operatively connected to the driving unit for controlling a rotational speed of the mixer body as a function of a flight operating condition.

Abstract: The present disclosure provides methods and systems for determining a synthesized engine parameter of a gas turbine engine. An initial model parameter is obtained from an onboard model associated with the gas turbine engine. A correction factor for the onboard model is determined by modifying a difference between the onboard model and an aero-thermal model of the gas turbine engine using first and second engine parameters and first and second operating conditions, wherein the first and second engine parameters are independent from one another over an operating envelope of the gas turbine engine. The initial model parameter is scaled by applying the correction factor thereto to obtain a corrected model parameter. The corrected model parameter is output as the synthesized engine parameter.

Abstract: An intake device for a gas turbine engine includes a snorkel and a particle separator. The snorkel is configured to be mounted to a panel defining at least a portion of a gas flow path within the gas turbine engine. The snorkel includes a tubular body extending between a closed end and an open end opposite the closed end. The snorkel further includes an inlet aperture formed through the tubular body adjacent the closed end. At least a portion of the snorkel is configured to be disposed within the gas flow path. The particle separator is mounted to the snorkel downstream of the inlet aperture. The particle separator includes at least one gas flow passage extending between a flow inlet and a flow outlet. The at least one gas flow passage is configured to remove particulate matter from the at least one gas flow passage upstream of the flow outlet.

Abstract: The gas turbine intake can have a swirl housing assembly with 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 around the central axis and between the tangential inlet and the annular outlet, the swirl housing assembly having a proximal portion defining a first portion of the swirl path, a distal portion defining a second portion of the swirl path, vanes located in the swirl housing assembly, the vanes circumferentially interspaced from one another relative the central axis and extending between the proximal portion and the distal portion, the proximal portion fastened to the distal portion via a plurality of fasteners, a gasket sandwiched between the proximal portion and the distal portion by the plurality of fasteners, the gasket extending in a radial plane relative the central axis.

Abstract: A failure detection method and system for a propeller control unit coupled to a propeller are provided. An actual value of a blade angle and/or a rotational speed of the propeller are obtained. A comparison between the actual value and a threshold is performed. In response to determining, based on the comparison, that the actual value exceeds the threshold, the propeller control unit is caused to adjust the blade angle to bring the blade angle and/or the rotational speed towards the threshold. A subsequent actual value of the blade angle and/or the rotational speed is obtained. From the subsequent value, it is determined whether the blade angle and/or the rotational speed has been brought towards the threshold. In response to determining that the blade angle and/or the rotational speed has failed to be brought towards the threshold, failure of the propeller control unit is detected and an alert is output.

Abstract: A structure for a gas turbine engine includes a first engine component, a second engine component and fasteners. The component apertures include first fastener apertures and intergroup apertures. The first fastener apertures are arranged into a plurality of groups. The first group is formed by N1-number of the first fastener apertures. The second group is formed by N2-number of the first fastener apertures where the N2-number is different than the N1-number. Each of the intergroup apertures is disposed circumferentially between and adjacent a respective circumferentially neighboring pair of the groups. The second engine component includes a surface and second fastener apertures. The surface axially engages the first engine component and covers the intergroup apertures. The fasteners attach the first engine component and the second engine component together. Each of the fasteners is mated with one of the first fastener apertures and one of the second fastener apertures.

Abstract: A measurement system for an aircraft gas turbine engine includes an instrumentation hub including at least one probe, and a shield hub positioned axially adjacent the instrumentation hub. The instrumentation hub is rotatable about a rotational axis. The shield hub includes at least one shield which is 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.

Abstract: An apparatus is provided for a turbine engine. This turbine engine apparatus includes a journal bearing extending axially along and circumferentially about an axis. The journal bearing extends radially between an inner side and an outer side. The journal bearing includes a bore, a passage and a groove. The bore extends axially within the journal bearing and is formed by the inner side. The passage extends radially within the journal bearing and is fluidly coupled with the bore and the groove. The groove is arranged at the outer side. The groove extends longitudinally within the journal bearing between a first end and a second end. The groove extends axially within the journal bearing between a first side and a second side. An axial distance between the first side and the second side changes as the groove extends longitudinally between the first end and the second end.

Abstract: A shaft assembly for an aircraft engine includes a first shaft coupled to a second shaft with a splined coupling made of an electrically-insulating material. The first and second shafts and the splined coupling are rotatable about an axis. A positioning device is mounted to the splined coupling and to the first shaft about the axis. The positioning device is displaceable along the axis relative to the first shaft to vary an axial position of the splined coupling.

Abstract: The present disclosure relates to methods and systems for validating a measurement machine. A group of validation measurements associated with a reference part is obtained. The group of validation measurements includes at least a first measurement associated with a first tolerance and a second measurement associated with a second tolerance, the second tolerance being smaller than the first tolerance. A dimension of the reference part associated with the first measurement is measured to obtain a measurement value. The measurement value is compared to a nominal value associated with the first measurement to obtain a measurement error. The measurement error is compared to the second tolerance associated with the second measurement. When the measurement error is less than the second tolerance, a validation signal is issued to the measurement machine.

Abstract: An apparatus is provided for a gas turbine engine. This gas turbine engine apparatus includes a first platform, a second platform, a plurality of vanes and a plurality of beams. The first platform extends axially along and circumferentially about an axis. The second platform extends axially along and circumferentially about the axis. The vanes are arranged circumferentially about the axis. Each of the vanes extends radially across a gas path between the first platform and the second platform. The vanes include a first vane movably connected to the first platform. The beams are arranged circumferentially about the axis. The beams are fixedly connected to the first platform and the second platform. The beams include a first beam extending radially through the first vane.

Abstract: Methods and systems for measuring an axial position of a rotating component of an engine are described herein. The method comprises obtaining a signal from a sensor coupled to the rotating component, the rotating component having a plurality of position markers distributed about a surface thereof, the position markers having an axially varying characteristic configured to cause a change in a varying parameter of the signal as a function of the axial position of the rotating component. Based on the signal, the method comprises determining a rotational speed of the rotating component from the signal, determining the varying parameter of the signal, and finding the axial position of the rotating component based on a known relationship between the axial position, the rotational speed, and the varying parameter of the signal.

Abstract: An aircraft engine, has: a low-pressure compressor and a high-pressure compressor located downstream of the low-pressure compressor; a gaspath valve upstream of the high-pressure compressor, the gaspath valve movable between an open configuration and a closed configuration; and a bypass flow path having in flow series a bypass inlet, a bypass valve, and a bypass outlet, the bypass inlet fluidly communicating with the gaspath upstream of at least one stage of the low-pressure compressor, the bypass valve having an open configuration in which the bypass valve allows a bypass flow and a closed configuration in which the bypass valve blocks the bypass flow, the bypass outlet fluidly communicating with the bypass inlet via the bypass valve and with the gaspath at a location in the gaspath fluidly downstream of the gaspath valve, downstream of the low-pressure compressor, and upstream of the high-pressure compressor.

Abstract: An apparatus is provided for a turbine engine. This turbine engine apparatus includes a journal bearing extending axially along and circumferentially about an axis. The journal bearing extends radially between a bearing inner side and a bearing outer side. The journal bearing includes a bore, a passage, a groove and a slot. The bore extends axially within the journal bearing and along the bearing inner side. The passage extends radially within the journal bearing and is fluidly coupled with the bore and the groove. The groove extends longitudinally within the journal bearing at the bearing outer side between a groove first end and a groove second end. At least a portion of the slot extends circumferentially about the axis within the journal bearing at the bearing outer side from the groove first end to the groove second end.

Abstract: A tangential on-board injector (TOBI), comprising: a body defining an annular passageway to receive cooling air, the TOBI defining a plurality of discharge nozzles; a rotating component mounted for rotation relative to the body about an axis of rotation; a seal extending between the body and the rotating component; a plurality of vanes circumferentially distributed about the axis of rotation and located downstream of the plurality of discharge nozzles relative to a flow of the cooling air circulating toward the seal from the plurality of discharge nozzles and upstream of the seal; and flow passages defined between the plurality of vanes, a flow passage of the flow passages extending along a passage axis, the passage axis having a tangential component at an outlet of the flow passage that is different than a tangential component of an exit flow axis of a nozzle of the plurality of discharge nozzles.

Abstract: A fuel system can include a first fuel circuit, a second fuel circuit, and an inert gas purge system operatively connected to both the first fuel circuit and the second fuel circuit to purge at least a portion of either or both of the first and/or second fuel circuit. The first fuel can be a liquid fuel and the second fuel can be a gaseous fuel. The first fuel circuit can include a first fuel manifold configured to fluidly communicate a first fuel supply with at least one dual fuel nozzles downstream of the first fuel manifold.

Abstract: Methods and tools for facilitating the installation and/or removal of a rotor on a shaft of a gas turbine engine are provided. The tool includes a stabilizer attachable to the shaft and including a first guide counterpart. The tool also includes a holder attachable to the rotor and including a second guide counterpart for engagement with the first guide counterpart of the stabilizer. Engagement of the first and second guide counterparts guides movement of the holder relative to the stabilizer along a guide axis and prevents movement of the holder relative to the stabilizer transverse to the guide axis.

Abstract: The nacelle can have an inlet portion having a duct wall and an outer skin, the duct wall being annular around an axis and having a surface forming a radially-outer delimitation to a gas path upstream of a fan area, the duct wall extending from a rounded inlet edge of the nacelle to the fan area, a cavity located inside the inlet portion, a compressed air inlet leading into the cavity, and an outlet fluidly connecting the cavity to the gas path, the outlet having a plurality of apertures disposed circumferentially around the duct wall, the apertures sloping circumferentially.

Abstract: A method is provided for assembling a rotor of a gas turbine engine. During this method, a rotor disk is provided that includes an axis and a plurality of slots arranged circumferentially about the axis in an array. A plurality of rotor blades are provided that include a plurality of airfoils and a plurality of attachments. Each of the rotor blades includes a respective one of the airfoils and a respective one of the attachments. Each of the attachments is inserted partially into a respective one of the slots. The rotor blades are rested on top of a blade support structure. The blade support structure is lowered axially downward along the rotor disk to simultaneously seat the attachments into the slots.