Abstract: A gas turbine engine (10) includes a compressor section, a turbine section, and an accessory gearbox (100). A turning unit (200) for the gas turbine engine includes an output assembly (204) configured to be mechanically coupled to the gas turbine engine, and an electric motor (202). The electric motor is operable to rotate, through the output assembly, one or more components of the compressor section or the turbine section at a rotational speed less than about fifty revolutions per minute during a shut-down condition of the gas turbine engine.

Abstract: A gear assembly for use with a turbomachine comprises a sun gear, a plurality of planet gear layshafts that each support a first stage planet gear and a second stage planet gear, and a ring gear. The sun gear is configured to rotate about a longitudinal centerline of the gear assembly, and the plurality of planet gear layshafts comprise an interior passage that receives one or more lubrication supply lines.

Abstract: An aspect of the present disclosure is directed to a method for mitigating rotor bow in a turbo machine. The method includes rotating a rotor over a first period of time; discontinuing rotation of the rotor for a second period of time; and iterating, over an overall period of time, rotation of the rotor over the first period of time and discontinuing rotation of the rotor for the second period of time.

Abstract: A variable pitch propeller assembly operatively coupled with an engine and methods for controlling the pitch of a plurality of propeller blades thereof is provided. In one example aspect, the variable pitch propeller assembly includes features for combining overspeed, feathering, and reverse functionality in a single secondary control valve. The secondary control valve is operable to selectively allow a controlled amount of hydraulic fluid to flow to or from a pitch actuation assembly such that the pitch of the propeller blades can be adjusted to operate the variable pitch propeller assembly in one of a constant speed mode, a feather mode, and a reverse mode.

Abstract: A system for torque measurement is generally provided. The system includes a sensor disposed between an outer bearing race and a static structure of a bearing assembly. The sensor is disposed adjacent along a thrust load direction to the outer bearing race. The system further includes a rotor assembly rotatably coupled to the bearing assembly, and a controller communicatively coupled to the sensor. The controller is configured to store and execute operations. The operations include determining a torque measurement from the rotor assembly based at least on an axial thrust load from the rotor assembly.

Abstract: A fastener cover for a flanged joint including first and second annular flanges extending about an axis, comprising: an annular, axially-extending, inboard wall; an annular, axially-extending outboard wall positioned radially outboard of the inboard wall; and a first radial wall interconnecting the inboard and outboard walls, wherein, collectively, the inboard and outboard walls and the first radial wall define a cavity for receiving a portion of a fastener; at least one fastener pocket including sidewalls extending axially away from the first radial wall and defining a tubular shape, which is closed off opposite the first radial wall by a floor plate having a clearance hole passing therethrough for accepting a shank of the fastener; and wherein the cover includes a balance weight receptacle for accepting at least one balance weight.

Abstract: A method (600) for testing control logic for a propeller driven by a gas turbine engine of an aircraft includes overriding (602) a signal indicating the aircraft is operating in a ground mode. The method can further include testing (604) minimum pitch protection logic when the signal is overridden; determining (606) the gas turbine engine is operating at a ground fine setting; restoring (608) the signal to an original state in which the signal indicates the aircraft is operating in the ground mode; modifying (610) pitch protection logic; determining (614) the propeller is operating at an overspeed condition; and testing (616) the propeller overspeed protection logic. In addition, the method can also determine (612) the propeller is operating at a low pitch condition when the gas turbine engine is operating at the ground fine setting.

Abstract: A gas turbine engine defining a longitudinal direction and a radial direction is provided.

Abstract: A gear assembly comprises a plurality of planet gear layshafts that have an outer surface having a plurality of gear surfaces and a surface having one or more bearing surfaces. The one or more bearing surfaces of the surfaces of the planet gear layshafts have a first case hardening depth and a first nitriding hardness depth. The gear surfaces of the outer surface of the planet gear layshafts have a second case hardening depth.

Abstract: A turbomachine engine can include a fan assembly, a vane assembly, a core engine, a gearbox, and a gearbox efficiency rating. The fan assembly can include a plurality of fan blades. The vane assembly can include a plurality of vanes, and the vanes can, in some instances, be disposed aft of the fan blades. The core engine can include one or more compressor sections and one or more turbine sections. The gearbox includes an input and an output. The input is coupled to the one or more turbine sections of the core engine and comprises a first rotational speed, the output is coupled to the fan assembly and has a second rotational speed, and a gear ratio of the first rotational speed to the second rotational speed is within a range of 4.1-14.0. The gearbox efficiency rating is 0.10-1.8.

Abstract: A turbine engine with at least a compressor section, combustor section, turbine section and a set of airfoils. The airfoils include geometric characteristics to create a high contraction ratio (CR), a low blade turning (BT) at a radially inward location the airfoil, a low solidity, or a low aspect ratio (AR).

Abstract: A control system (50) for a turbopropeller engine (2) of an aircraft (1) having a gas turbine (11) and a propeller assembly (3) coupled to the gas turbine (11), the gas turbine (11) having a compressor (12) coupled to an air intake (13) and a temperature sensor (22) being arranged in the air intake (13) to measure the temperature of engine intake air and provide a sensed temperature (T1sens); the control system envisages: a compensation system (40) to receive the sensed temperature (T1sens) from the temperature sensor (22) and to add to the sensed temperature (T1sens) a compensation quantity (comp) to compensate for a delay introduced by the time constant (?) of the temperature sensor (22) and generate a compensated temperature (T1comp); and a control unit (20) to perform engine control operations based on the compensated temperature (T1comp).

Abstract: A turbomachine includes a rotatable annular outer drum rotor connected to a first plurality of blades. The rotatable annular outer drum rotor is constructed of, at least, a first drum segment and a second drum segment. The turbomachine further includes a retaining ring arranged and secured between the first and second drum segments of the rotatable annular outer drum rotor for radially retaining each of the first plurality of blades via their respective blade root portions within the rotatable annular outer drum rotor.

Abstract: A turbomachine engine according to aspects of the present disclosure is provided. The engine includes a fan assembly including a plurality of fan blades, and a core engine surrounded by an outer casing. The core engine includes a power output component operably connected to the fan assembly, a first input power source and a second input power source. The first input power source is counter-rotatable relative to the second input power source. The core engine includes a gear assembly operably connected to the power output component and configured to receive power from the first input power source and the second input power source.

Abstract: The present disclosure is directed to a shaft assembly (95) for a turbine engine (10), wherein the turbine engine includes a fan or propeller assembly (14) and an engine core (20), and further wherein the fan or propeller assembly includes a gearbox (45), and wherein the engine core includes one or more rotors (32). The shaft assembly (95) includes a flexible shaft (100) defining a first end (101) and a second end (102) along the axial direction, wherein the first end is connected to the engine core (20) and the second end is connected to the gearbox (45), and wherein a plurality of splines (110) is defined at the second end (102) and coupled to a spline interface (46) at the gearbox (45); and a coupling (120) extended at least partially in the radial direction and coupled to the engine core and the flexible shaft.

Abstract: A gear assembly for an aeronautical engine that includes a first gear disposed at a centerline axis of the gear assembly; a second gear coupled to the first gear in adjacent radial arrangement to form a first mesh between the first gear and the second gear; a third gear coupled to the second gear in adjacent radial arrangement to form a second mesh between the second gear and the third gear; a collector rotatably coupled with the third gear; and a lubricant input portion disposed between a portion of the first gear and the second gear such that a first supply opening of the lubricant input portion is directed at the first mesh between the first gear and the second gear. The first supply opening provides a flow of lubricant to the first mesh with a portion of the flow of lubricant is collected by the collector.

Abstract: A gear transmission for aeronautical applications including an input shaft rotating about an axis, an output shaft rotating about the axis, and a transfer group for transferring the torque from the input shaft to the output shaft. The transfer group includes a first torque splitting stage, receiving the torque from the input shaft, and a second torque splitting stage, receiving the torque from the first stage. The first stage presents at least one first rotating member and the second stage presents at least one second rotating member. The input shaft and the first rotating member cooperate with one another at respective interaction surfaces. The rotating members cooperate with one another at respective friction surfaces. One of the interaction surfaces has first engagement elements, and another of the interaction surfaces has second engagement elements that are clutch coupled to one another.

Abstract: A control system (50) for an electro-hydraulic servo-actuator (26) envisages: a controller (55), to generate a control current (Ic), designed to control actuation of the electro-hydraulic servo-actuator (26), implementing a position control loop based on a position error (ep), the position error (ep) being a difference between a reference position (Posref) and a measured position (Posmeas) of the electro-hydraulic servo-actuator (26); and a limitation stage (58), coupled to the controller (55) to provide a limitation of the actuator speed of the electro-hydraulic servo-actuator (26); the limitation stage (58) limits a rate of change of a driving current (Id) to be supplied to the electro-hydraulic servo-actuator (26), in order to limit the actuator speed.

Abstract: A gear assembly of an aircraft including an engine is generally provided. The gear assembly includes a first gear meshed with a second gear to define a gear mesh, and a walled lubricant tank defining a lubricant reservoir and a reservoir inlet opening. The reservoir inlet opening is defined adjacent to an out-of-mesh side of the gear mesh. At least a portion of lubricant from the gear mesh enters the lubricant reservoir through the reservoir inlet opening.

Abstract: An electronic control system (30) for a turbopropeller engine (1) having a gas turbine (2, 4, 5, 6) and a propeller (7), coupled to the gas turbine, the control system (10) having a propeller control unit (14) and a turbine control unit (15) to jointly control engine power output based on an input request (PLA), wherein the propeller control unit (14) has a first reference generator (16), to determine a reference propeller speed (Npref) based on the input request (PLA), and a first regulator (19), to regulate a propeller speed (Np). The propeller control unit (14) has a reference correction stage (31) to apply a correction to the reference propeller speed (Npref) and generate thereby a corrected reference propeller speed (I), and the first regulator (19) regulates the propeller speed (Np) based on the corrected reference propeller speed (I) to achieve optimized efficiency.