Abstract: An aircraft engine reduction gearbox includes a power input and a power output, and an epicyclic gear train engaged with the power input and the power output. The epicyclic gear train includes a sun gear engaged with the power input and centrally disposed to define a center axis of the epicyclic gear train. Compound planet gears are mounted to a carrier and rotatable about respective planet gear axes. Each compound planet gear has an input gear in meshed engagement with the sun gear, and output gears axially spaced from the input gear. Ring gears are axially spaced apart and rotatable about the center axis. The ring gears are engaged with the power output. Each ring gear is in meshed engagement with one of the output gears.

Abstract: A vehicle includes at least one side bay equipped with a window, and a device for displaying at least one item of information on the window. The display device includes an image projector fastened to a ceiling of the vehicle. The display device emits light rays. A system of at least one mirror is arranged to reflect light rays emitted by the image projector in the direction of the window.

Abstract: Systems and methods of storing phase history, and enhancing and restoring phase accuracy for a embedded Global Navigation Satellite System (GNSS) receiver include storing a phase history of the GNSS receiver output; determining an expected value of phase of the GNSS receiver output based on the phase history; and, responsive to a degradation of the GNSS receiver output, adjusting the GNSS receiver output utilizing the expected value of phase. The systems and method can further include, responsive to degradation being a loss of the GNSS receiver output, utilizing a holdover output from a physical frequency reference and with a phase adjusted based on the expected value of phase, and, responsive to the variation, utilizing the phase history to re-generate the GNSS receiver output for performance enhancement.

Abstract: A gas turbine engine with an accessory gearbox. The accessory gearbox has a gear shaft rotatable about a gear shaft axis. The gear shaft has a first end drivingly engaged to a first accessory and a second end drivingly engaged to a second accessory. The gearbox has a spline made of a polymer material and rotatably coupled to one of the first and second ends of the gear shaft, and to a corresponding one of a first and second accessory shafts of the first and second accessories. The spline is rotatable about the gear shaft axis.

Abstract: A gas turbine engine with an accessory gearbox. The accessory gearbox is rotatably coupled to the engine drive shaft. The gearbox has a gear shaft rotatable about a gear shaft axis. The gear shaft has a first end drivingly engaged to a first accessory and a second end drivingly engaged to a second accessory.

Abstract: An assembly comprising: a nut having a cylindrical body with a threaded external surface, an axially extending interior tool socket, and a radially outwardly extending flange at a proximal end of the cylindrical body; a first component including a hollow cylindrical tube with a connector end having a radially inwardly extending shoulder, the radially inwardly extending shoulder abutting the radially outwardly extending flange of the nut in an assembled position; and a second component including an annular hub with a threaded internal surface matching the threaded external surface of the nut, and an annular mounting surface abutting the connector end of the propeller shaft in the assembled position.

Abstract: A planet carrier for an epicyclic gear train of a gas turbine engine gearbox includes a centrally disposed torque transfer coupling, a pair of carrier plates parallel to each to each other and perpendicular to a longitudinal axis, and center arms radially extending radially outward from the torque transfer coupling to the carrier plates. A central bore is concentric with the longitudinal axis and forming a torque transmission point on the planet carrier. The center arms are axially disposed between the axially spaced apart carrier plates and have radially outer ends which terminate at an outer perimeter of the carrier plates. The center arms are thus entirely radially disposed within a radial outer perimeter of the carrier plates.

Abstract: Oil tanks for gas turbine engines and associated assembly methods are disclosed. In one exemplary embodiment, an oil tank is configured to be installed to occupy a radially-inner space defined by an annular radial air inlet duct of a reverse flow gas turbine engine. The oil tank may comprise a first tank portion and a second tank portion assembled together to cooperatively define an interior volume of the tank. An optional intermediate spacer may be disposed between the first tank portion and the second tank portion in order to form an oil tank of a larger size.

Abstract: A gas turbine engine has an in-line mounted accessory gear box (AGB) and an accessory drivingly connected to the AGB, the accessory being oriented transversally to the engine centerline.

Abstract: An aircraft engine reduction gearbox includes a power input and a power output, and an epicyclic gear train engaged with the power input and the power output. The epicyclic gear train includes a sun gear engaged with the power input and centrally disposed to define a center axis of the epicyclic gear train. Compound planet gears are mounted to a carrier and rotatable about respective planet gear axes. Each compound planet gear has an input gear in meshed engagement with the sun gear, and output gears axially spaced from the input gear. Ring gears are axially spaced apart and rotatable about the center axis. The ring gears are engaged with the power output. Each ring gear is in meshed engagement with one of the output gears.

Abstract: An epicyclic gear train including a central sun gear, an outer ring gear, and a number of planet gears which are mounted to a planet carrier. The planet carrier includes a centrally disposed torque transfer coupling with a torque transmission point at an axial end thereof. First and second carrier plates extend radially from the torque transfer coupling and are axially spaced apart to support the planet gears therebetween at aligned gear mounting points. The first carrier plate is closer to the torque transfer point than the second carrier plate. The second carrier plate has a stiffness that is greater than that of the first carrier plate.

Abstract: A gas turbine engine with an accessory gearbox. The accessory gearbox is rotatably coupled to the engine drive shaft. The gearbox has a gear shaft rotatable about a gear shaft axis. The gear shaft has a first end drivingly engaged to a first accessory and a second end drivingly engaged to a second accessory.

Abstract: A planetary gear train for an aircraft engine, has: a sun gear; planet gear assemblies having main gears meshed with the sun gear, fore lateral gears and aft lateral gears disposed on opposite sides of the main gears and rotating therewith; journal bearings rotatably supporting the planet gear assemblies for rotation about rotation axes, gaps defined between the journal bearings and the planetary gear assemblies; a planet carrier supporting the journal bearings; a fore ring gear meshed with the fore lateral gears; an aft ring gear meshed with the aft lateral gears; and a lubrication system extending within the planet carrier and hydraulically connected to the gaps between the journal bearings and the planet gear assemblies.

Abstract: A planetary gear train for an aircraft engine, has a sun gear rotatable about a rotation axis, planet gears meshed with the sun gear and circumferentially distributed about the rotation axis, and a ring gear meshed with the planet gears, a planet carrier having first and second disk members axially offset from one another relative to the rotation axis, the planet carrier having planet bearings secured to the first and second disk members and extending axially therebetween, the planet gears rotatably supported by the planet bearings, the planet carrier having connecting members secured to both of the first and second disk members, the connecting members located circumferentially between the planet bearings, a lubrication network extending within the planet carrier and in fluid flow communication with the planet bearing and extending within the connecting members, the connecting members defining outlets of the lubrication network, the outlets oriented toward the sun gear.

Abstract: In one aspect, there is provided a gear train having a sun gear, planet gear assemblies. Each planet gear assembly has a main gear meshed with the sun gear, a fore lateral gear and an aft lateral gear disposed on opposite sides of the main gear and rotating therewith. A diameter of the main gear is different than a diameter of the fore and aft lateral gears. Each planet gear assembly is rotatably mounted on a bearing for rotation about an axis. The bearing includes a journal defining two undercuts. A planet carrier rotatably supports the planet gear assemblies. Ring gears are meshed with the fore and aft lateral gears. One of the sun gear, the planet carrier, and the ring gears connected to an input, one is connected to an output, and rotation of a remaining one is limited.

Abstract: The epicyclic gear stage has a carrier body receiving the planet gears via corresponding planet bearings, a first bearing plane where a first axial end of the planet bearings are received by the carrier body, a second bearing plane where a second axial end of the planet bearings are received by the carrier body, a torque transfer body made integral to the carrier body externally to the sun gear, at a balanced torque transfer plane located between the first bearing plane and the second bearing plane, and extending away therefrom to a shaft coupler, for transferring torque between the carrier body and a shaft, and an oil network extending within the carrier, the oil network having an inlet in the torque transfer body, extending within the torque transfer body and into the carrier body, and extending within the carrier body and into the planet bearings.

Abstract: A turbo propeller engine comprises a housing circumferentially extending around a longitudinal axis and disposed around a gearbox. The turbo propeller engine includes a propeller outside of the housing and a shaft surrounded in part by the housing and extending along the longitudinal axis. The shaft has a front end and a rear end. The propeller is mounted to the front end. The rear end is in a driven engagement with an output of the gearbox. The shaft is rotatably supported by a first bearing and by a second bearing separated from the first bearing by an axial distance along the longitudinal axis. The first and second bearings are disposed on opposite sides of the gearbox. The first bearing is disposed between the shaft and the housing, the second bearing is disposed between the housing and a component of the gearbox to rotatingly support the component of the gearbox.

Abstract: In one aspect, there is provided a gear train having a sun gear, planet gear assemblies. Each planet gear assembly has a main gear meshed with the sun gear, a fore lateral gear and an aft lateral gear disposed on opposite sides of the main gear and rotating therewith. A diameter of the main gear is different than a diameter of the fore and aft lateral gears. Each planet gear assembly is rotatably mounted on a bearing for rotation about an axis. The bearing includes a journal defining two undercuts. A planet carrier rotatably supports the planet gear assemblies. Ring gears are meshed with the fore and aft lateral gears. One of the sun gear, the planet carrier, and the ring gears connected to an input, one is connected to an output, and rotation of a remaining one is limited.

Abstract: There is described herein methods and systems for detecting a shaft event in a gas turbine engine comprising a power turbine having a first shaft extending in a first direction and a second shaft extending in a second direction opposite from the first direction. A first speed measurement is obtained at a first location along the first shaft and a second speed measurement is obtained at a second location along the second shaft. A speed ratio is determined between the first speed measurement and the second speed measurement, and is compared to a detection threshold. The shaft event is detected when the speed ratio is beyond the detection threshold.

Abstract: In a method for authenticating a user, a device accesses a key and an initial vector. The vector is generated by using a first algorithm, a reference vector and reference user authentication data. The device accesses data and provided user authentication data. The device generates an intermediary vector by using a second algorithm, the initial vector and the user authentication data. The device generates a cryptogram by using a third algorithm, the key, the intermediary vector and the data. A server receives a request for authenticating a user accompanied with the cryptogram and the data. The server accesses the key and the reference vector. The server generates a reference cryptogram by using the third algorithm, the key, the reference vector and the data. The server verifies whether the reference cryptogram matches the cryptogram. If the reference cryptogram matches the cryptogram, the server authenticates the user.