Abstract: A gas turbine engine comprises a fan, a core turbine engine coupled to the fan, a fan case housing the fan and the core turbine engine, a plurality of outlet guide vanes extending between the core turbine engine and the fan case, and an acoustic spacing. The fan comprises a plurality of fan blades that define a fan diameter and a BEAL. The fan case comprises an inlet and an inlet length between the inlet and the fan. The acoustic spacing comprises a distance between the fan and the plurality of outlet guide vanes, and in combination with the BEAL determines an acoustic spacing ratio of the gas turbine engine.

Abstract: A gas turbine engine includes a gearbox assembly that includes a gearbox and a gutter for collecting a gearbox lubricant scavenge flow from the gearbox. The gutter is characterized by a lubricant extraction volume ratio between 0.01 and 0.3. The lubricant extraction volume ratio defined by: V G V GB . V G is a gutter volume of the gutter and VGB is a gearbox volume. The gas turbine engine includes a lubrication system that includes a lubricant tank that stores lubricant, one or more primary gearbox lubricant supply lines, one or more secondary gearbox lubricant supply lines, and a lubricant pump for supplying the lubricant to the gearbox assembly through the primary gearbox lubricant supply lines and the secondary gearbox lubricant supply lines. The lubrication system modulates a mass flow rate of the lubricant to the gearbox assembly through the primary gearbox lubricant supply lines or the secondary gearbox lubricant supply lines.

Abstract: Systems, apparatus, articles of manufacture, and methods are disclosed to improve fan operability control using smart materials. An engine comprising an engine surface in an airflow path, a sensor positioned on the engine surface, and a smart-material-based feature positioned on the engine surface, the smart-material-based feature triggered to modify the airflow path when the sensor outputs an indication of a detected deviation from a reference value of an operating parameter of the engine.

Abstract: A mounting assembly for a gearbox assembly of a gas turbine engine includes at least one mounting member configured to mount a gear of the gearbox assembly to a component of the gas turbine engine, the at least one mounting member characterized by a lateral impedance parameter, a bending impedance parameter, and a torsional impedance parameter. A gas turbine engine includes the mounting assembly. The at least one mounting member may be a flex mount, a fan frame, or a flex coupling. The gas turbine engine includes an electric power system including at least one electric machine. The electric power system includes a plurality of power converters and a plurality of power distribution management units. At least two of the plurality of power converters or the plurality of power distribution management units are integrated together in a single housing.

Abstract: A gearbox assembly includes a gearbox and a gutter for collecting a gearbox lubricant scavenge flow from the gearbox. The gutter is characterized by a lubricant extraction volume ratio between 0.01 and 0.3, inclusive of the endpoints. The lubricant extraction volume ratio is defined by V G V GB . VG is a gutter volume of the gutter and VGB is a gearbox volume of the gearbox. A gas turbine engine includes the gearbox assembly and a lubrication system. The lubrication system includes a tank that stores a lubricant therein, one or more lubricant pumps for generating a flow of lubricant from the tank to the gearbox assembly, and a flow rate control valve. The flow rate control valve has a flow inlet and a flow outlet and defines a variable throughput from the flow inlet to the flow outlet for controlling a flowrate of the lubricant to the gearbox assembly.

Abstract: A gearbox assembly includes a gearbox and a gutter for collecting a gearbox lubricant scavenge flow from the gearbox. The gutter is characterized by a lubricant extraction volume ratio between 0.01 and 0.3, inclusive of the endpoints. The lubricant extraction volume ratio defined by: VG/VGB. VG is a gutter volume of the gutter and VGB is a gearbox volume. A gas turbine engine includes the gearbox assembly. The gas turbine engine includes an electric power system including at least one electric machine. The electric power system includes a plurality of power converters and a plurality of power distribution management units. At least two of the plurality of power converters or the plurality of power distribution management units are integrated together in a single housing.

Abstract: A gearbox assembly includes a gearbox and a gutter for collecting a gearbox lubricant scavenge flow from the gearbox. The gutter is characterized by a lubricant extraction volume ratio between 0.01 and 0.3, and given by V G V G ? B . VG is a gutter volume of the gutter and VGB is a gearbox volume. A gas turbine engine includes a combustion section and the gearbox assembly. A fuel delivery system includes a fuel supply line for delivering fuel to the combustion section. A lubrication system includes a lubricant supply line for delivering lubricant to the gearbox assembly. A thermal management system includes a fuel-lubricant heat exchanger for cooling the lubricant with the fuel. The thermal management system selectively directs the fuel through fuel bypass lines or the lubricant through lubricant bypass lines to bypass the fuel-lubricant heat exchanger based on a fuel temperature or a lubricant temperature.

Abstract: A gearbox assembly includes a gearbox and a gutter for collecting a gearbox lubricant scavenge flow from the gearbox. The gutter is characterized by a lubricant extraction volume ratio between 0.01 and 0.3 that is defined by V G V G ? B . VG is a gutter volume of the gutter and VGB is a gearbox volume. A gas turbine engine includes the gearbox assembly, a fan, a combustor that generates combustion gases, a turbine, a nacelle that surrounds the fan, and a steam system. The combustor and the turbine define a core air flowpath. Core air flows through the core air flowpath. The steam system that extracts water from the combustion gases, vaporizes the water to generate steam, and injects the steam into the core air flowpath to add mass flow to the core air. A bypass ratio of the gas turbine engine is in a range of 18:1 to 100:1.

Abstract: A lubrication system for a gearbox assembly for a turbine engine. The gearbox assembly includes a gear assembly including one or more gears and one or more bearings. The lubrication system includes a sump. The sump is a primary reservoir that has a first lubricant level. The lubrication system also includes a secondary reservoir in the gearbox assembly. The secondary reservoir has a second lubricant level that is greater than the first lubricant level. A plurality of drain ports includes a first drain port and a second drain port. The lubrication system fills the secondary reservoir with lubricant between the first lubricant level and the second lubricant level and a portion of the lubricant drains though the second drain port. The one or more gears collects the lubricant to supply the lubricant from the secondary reservoir to the one or more gears or to the one or more bearings.

Abstract: An engine includes a gearbox coupled to a first element and a second element. The engine may include a first speed sensor positioned on an input side of the gearbox, the first speed sensor operable to detect a first speed of the first element. The engine may further include a second speed sensor positioned on an output side of the gearbox, the second speed sensor operable to detect a second speed of the second element. The engine includes a controller comprising a processor and a memory coupled to the processor. The processor may be configured to receive data from the first speed sensor and the second speed sensor. The processor is also configured to detect a trigger event based on the data from the first speed sensor and the data from the second speed sensor. Upon detecting the trigger event, the processor communicates a command to an engine operational system.

Abstract: Fluid-filled thrust link apparatus and associated method are disclosed. A thrust link for an aircraft engine includes a first wall having a forward portion and an aft portion at opposite ends of the thrust link, the forward portion coupled to the aircraft engine, the aft portion coupled to the aircraft engine, a pylon, or an aircraft associated with the aircraft engine, and a second wall within an interior area surrounded by the first wall, the second wall spaced apart from the first wall, a space between the first wall and the second wall defining a channel within the interior area, the channel including a fluid, the fluid pressurized based on a damping ratio to withstand a resonant vibration frequency generated by the aircraft engine.

Abstract: A gas turbine engine includes a fan, a combustor positioned in a core air flowpath that generates combustion gases, a steam system that extracts water from the combustion gases and generates steam, and a gearbox assembly. The steam system includes water storage devices that store the water therein. The water storage devices include a first state in which a level of the water increases or is maintained and a second state in which the level of the water decreases as the water flows through the water storage devices. The gearbox assembly includes a gearbox and a gutter for collecting a gearbox lubricant scavenge flow from the gearbox. The gutter is characterized by a lubricant extraction volume ratio between 0.01 and 0.3, inclusive of the endpoints. The lubricant extraction volume ratio defined by: V G V G ? B · V G is a gutter volume of the gutter and VGB is a gearbox volume.

Abstract: Variable diameter thrust link apparatus are disclosed. A thrust link for an aircraft engine includes a forward end coupled to the aircraft engine, the forward end having a first diameter, and an aft end coupled to the aircraft engine or a pylon, the aft end having the first diameter, wherein the thrust link defines a thrust link span that extends from the forward end to the aft end, wherein a second diameter greater than the first diameter is defined between the forward end and the aft end, wherein the second diameter spans a center diameter span that is equivalent to or between 60% and 90% of the thrust link span.

Abstract: A gas turbine engine is provided having a turbomachine comprising a compressor section, a combustion section, and a turbine section arranged in serial flow order, the compressor section having a high pressure compressor defining a high pressure compressor exit area (AHPCExit) in square inches and the turbine section having a drive turbine defining a drive turbine exit area (ADTExit) in square inches, the turbomachine further comprising a drive turbine shaft coupled to the drive turbine; wherein the gas turbine engine defines a maximum exhaust gas temperature (EGT) in degrees Celsius, a maximum drive turbine shaft torque (TOUT) in Newton meters, and a corrected specific power (CSP) in Newtons squared times degrees Celsius over meters squared, wherein the corrected specific power is determined as follows: ( T OUT A DTExit ) 2 * EGT A HPCExit * 1 ? 0 - 1 ? 1 ; wherein CSP is greater than 0.0001194×EGT2?0.103×EGT+22.14 and less than 0.0003294×EGT2?0.306×EGT+77.

Abstract: A gas turbine engine includes a gearbox assembly that includes a gearbox and a gutter for collecting a gearbox lubricant scavenge flow from the gearbox. The gutter is characterized by a lubricant extraction volume ratio between 0.01 and 0.3, inclusive of the endpoints. The lubricant extraction volume ratio defined by: V G V G ? B · V G is a gutter volume of the gutter and VGB is a gearbox volume. The gas turbine engine includes a lubricant flow control system that includes a variable flow lubricant pump that generates a pump variable flow of lubricant to the gearbox assembly. The gearbox assembly has a variable consumption demand for delivery of lubricant. A lubricant flow controller is configured to generate a pump control command for the variable flow lubricant pump to produce the pump variable flow of lubricant based on the variable consumption demand.

Abstract: A gearbox assembly includes a gearbox having a gear assembly and a gutter for collecting a gearbox lubricant scavenge flow from the gearbox. The gutter is characterized by a lubricant extraction volume ratio between 0.01 and 0.3, inclusive of the endpoints. The lubricant extraction volume ratio is defined by V G V GB . VG is a gutter volume of the gutter and VGB is a gearbox volume. A gas turbine engine includes the gearbox assembly and a lubrication system. The lubrication system includes a sump that is a primary reservoir having a first lubricant level and a secondary reservoir in the gearbox assembly. The secondary reservoir has a second lubricant level. The lubrication system fills the secondary reservoir with a lubricant between the first lubricant level and the second lubricant level. The gear assembly collects the lubricant in the secondary reservoir to supply the lubricant to the gear assembly.

Abstract: Viscous damper apparatus and associated methods to control a response to a resonant vibration frequency are disclosed. An apparatus to support an aircraft engine includes a thrust link including a forward end and an aft end, the forward end of the thrust link coupled to the aircraft engine, and a damper including a piston rod coupled to the aft end of the thrust link, the piston rod including a piston, and a chamber including a fluid, the piston to move within the chamber.

Abstract: A turbine engine for an aircraft. The turbine engine includes a core turbine engine and a steam system. The steam system extracts water from combustion gases, vaporizes the water to generate steam, and injects the steam into a core air flow path of the core engine to add mass flow to core air. A core hot gas path component may be fluidly connected to a hot gas path that routes combustion gasses from the combustor. The core turbine engine may also include a turbine fluidly connected to the hot gas path to receive the combustion gases. The turbine may include a turbine airfoil. Each of the core hot gas path component and the turbine airfoil includes a combustion-gas-facing surface facing the hot gas path. A hydrophobic coating is formed on the combustion-gas-facing surface, reducing wetting of water vapor within the combustion gases on the core hot gas path component.

Abstract: A turbine engine for an aircraft. The turbine engine includes a combustor and a steam system. Fuel and steam are injected into the combustor to mix with compressed air to generate a fuel and air mixture. The fuel and air mixture is combusted in the combustor to generate combustion gases. The steam system is fluidly coupled to the combustor as the steam source to provide steam to the combustor. The steam system includes a hot gas path and a steam hot gas path component. The hot gas path is fluidly coupled to the combustor to receive the combustion gases and to route the combustion gases through the steam system. The steam hot gas path component includes a wall having a combustion-gas-facing surface facing the hot gas path and a hydrophobic coating formed on the combustion-gas-facing surface.

Abstract: A turbine engine for an aircraft. The turbine engine includes a combustor and a steam system. Fuel and steam are injected into the combustor to mix with compressed air to generate a fuel and air mixture. The fuel and air mixture is combusted in the combustor to generate combustion gases. The steam system is fluidly coupled to the combustor as the steam source to provide steam to the combustor. The steam system includes a hot gas path and a steam hot gas path component. The hot gas path is fluidly coupled to the combustor to receive the combustion gases and to route the combustion gases through the steam system. The steam hot gas path component includes a wall having a combustion-gas-facing surface facing the hot gas path and a hydrophobic coating formed on the combustion-gas-facing surface.