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: Methods and apparatus to determine engine status with plenum measurements are disclosed. A disclosed example apparatus includes interface circuitry, and programmable circuitry configured to at least one of instantiate or execute machine readable instructions to: determine, based on output from at least one sensor, at least one parameter corresponding to: (i) a first plenum in a casing of a gas turbine engine, the first plenum positioned at or downstream of a volume at which flows from respective ones of bleed offtakes of the gas turbine engine are combined, and (ii) a second plenum in the casing, the second plenum positioned upstream of the first plenum, a status of at least one of the bleed offtakes or the at least one sensor based on the at least one parameter and provide or indicate a notification of the status in response to the status indicating improper operation of at least one of the bleed offtakes or the at least one sensor.

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 includes a fan, an engine core, a fan case housing the fan and the engine core, a plurality of outlet guide vanes extending between the engine core and the fan case, and an acoustic spacing. Relationships between acoustic spacing and a high-speed shaft rating allow for a gas turbine engine that reduces noise emissions while maintaining high performance.

Abstract: A gas turbine engine includes a fan, a core engine coupled to the fan, a fan case housing the fan and the core engine, a plurality of outlet guide vanes extending between the core engine and the fan case, and an acoustic spacing. The fan includes a plurality of fan blades that define a fan diameter and a BEAL. The acoustic spacing includes a distance between the fan and the outlet guide vanes, and in combination with the BEAL determines an acoustic spacing ratio of the gas turbine engine. The combination of the acoustic spacing and a corrected specific thrust of the gas turbine engine provide enhanced propulsive efficiency.

Abstract: Methods and apparatus to vary geometry of a thrust link are disclosed. An apparatus to support an aircraft engine includes a thrust link including a forward end coupled to the aircraft engine, an aft end coupled to the aircraft engine or a pylon, and a bumper coupled to (i) the thrust link between the forward end and the aft end and (ii) to an annular fan casing, a nacelle, the pylon, or an aircraft associated with the aircraft engine, a bumper distance percentage defined between the aft end and a location on the thrust link at which the bumper couples to the thrust link, wherein the location is aft of the forward end.

Abstract: A gas turbine engine comprises a fan, a core engine coupled to the fan, a fan case housing the fan and the core engine, a plurality of outlet guide vanes extending between the core engine and the fan case, a blade effective acoustic length (BEAL), and an acoustic spacing. The fan comprises a fan disk, a fan diameter, and a plurality of fan blades. 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. The fan case comprises an inlet and an inlet length between the inlet and the fan, and in combination with the fan disk determines a disk spacing length and a disk-to-inlet length (DIL) ratio of the gas turbine engine.

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 blades feature a low aspect ratio, reducing blade count while maintaining thrust and efficiency. Efficiency is enhanced through a determined relationship between fan blade count, aspect ratio, and specific flow.

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 first thrust link including a forward end and an aft end, the forward end of the first thrust link coupled to the aircraft engine, a second thrust link including a forward end and an aft end, the forward end of the second thrust link coupled to the aircraft engine, and a damper coupled to the aft end of the first thrust link and to the aft end of the second thrust link.

Abstract: Methods and apparatus to determine engine status with plenum measurements are disclosed. A disclosed example apparatus for use with a gas turbine engine having bleed offtakes includes at least one sensor on or within the gas turbine engine, the at least one sensor to measure at least one parameter corresponding to: a first plenum within a casing of the gas turbine engine, the first plenum positioned at or downstream of a volume at which flows from respective ones of the bleed offtakes are combined, and a second plenum within the casing, the second plenum positioned upstream of the first plenum, and an interface to communicatively couple the at least one sensor to a controller, the controller to determine a status of the bleed offtakes based on the at least one parameter.

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. A gearbox assembly with improved engine efficiency rating used in combination with the acoustic spacing provides an improved and balanced engine architecture.

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 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 acoustic spacing parameter, in combination with composite fan blades that include one or both of a fan leading edge to trailing edge compression factor (FLTCF) and a fan leading edge to trailing edge opening ratio (FLTOR), provide improved performance and reduced acoustic noise.

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 disclosed example non-transitory machine readable storage medium includes instructions to cause programmable circuitry to at least determine, based on output from at least one sensor, (i) a first parameter corresponding to a first position in a casing of a gas turbine engine, the first position at or downstream of a volume at which flows from respective ones of bleed offtakes are combined, and (ii) a second parameter corresponding to a second position in a casing of a gas turbine engine, the second position upstream from the first position, determine a status of at least one of the bleed offtakes or the at least one sensor based on the first and second parameters, and provide or indicate the status in response to the status indicating improper operation of at least one of the bleed offtakes or the at least one sensor.

Abstract: A gas turbine engine comprises a fan assembly, a core engine coupled to the fan assembly, a fan case housing the fan assembly and the core engine, a plurality of outlet guide vanes extending between the core engine and the fan case, and an acoustic spacing. The fan assembly comprises a plurality of fan blades that define a fan diameter and a blade effective acoustic length (BEAL). The acoustic spacing comprises a distance between the fan assembly and the plurality of outlet guide vanes, and in combination with the BEAL determines an acoustic spacing ratio of the gas turbine engine. A gearbox assembly with an improved engine efficiency rating used in combination with the acoustic spacing provides an improved and balanced engine architecture.

Abstract: A gas turbine engine includes a fan, a core engine coupled to the fan, a fan case housing the fan and the core engine, and outlet guide vanes extending between the core engine and the fan case. The fan includes fan blades with leading edge protectors. The gas turbine engine further includes an acoustic spacing, which in combination with the fan blades having leading edge protectors effectively reduces noise emissions, enhances aerodynamic efficiency, and improves structural durability.

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. A gearbox assembly with improved engine efficiency rating used in combination with the acoustic spacing provides an improved and balanced engine architecture.

Abstract: A gas turbine engine comprises a fan assembly, a core engine coupled to the fan assembly, a fan case housing the fan assembly and the core engine, a plurality of outlet guide vanes extending between the core engine and the fan case, and an acoustic spacing. The fan assembly comprises a plurality of fan blades that define a fan diameter and a blade effective acoustic length (BEAL). The acoustic spacing comprises a distance between the fan assembly and the plurality of outlet guide vanes, and in combination with the BEAL determines an acoustic spacing ratio of the gas turbine engine. A gearbox assembly with an improved engine efficiency rating used in combination with the acoustic spacing provides an improved and balanced engine architecture.

Abstract: A gas turbine engine includes a fan, a core engine coupled to the fan, a fan case housing the fan and the core engine, and outlet guide vanes extending between the core engine and the fan case. The fan includes fan blades with leading edge protectors. The gas turbine engine further includes an acoustic spacing, which in combination with the fan blades having leading edge protectors effectively reduces noise emissions, enhances aerodynamic efficiency, and improves structural durability.