26, a combustion section 28 including a combustor 30, a turbine section 32 including a HP turbine 34, and a LP turbine 36, and an exhaust section 38.

The fan section 18 includes a fan casing 40 surrounding the fan 20. The fan 20 includes a plurality of fan blades 42 disposed radially about the engine centerline 12. A fan inlet 83 of the fan section 18 is defined at the upstream or forward end 14 of the gas turbine engine 10. A fan exhaust 84 is defined downstream end of the fan inlet 83. The HP compressor 26, the combustor 30, and the HP turbine 34 form a core 44 of the gas turbine engine 10, which generates combustion gases. The core 44 is surrounded by a core casing 46, which can be coupled with the fan casing 40.

A HP shaft or spool 48 disposed coaxially about the engine centerline 12 of the gas turbine engine 10 drivingly connects the HP turbine 34 to the HP compressor 26. A LP shaft or spool 50, which is disposed coaxially about the engine centerline 12 of the gas turbine engine 10 within the larger diameter annular HP spool 48, drivingly connects the LP turbine 36 to the LP compressor 24 and fan 20. The spools 48, 50 are rotatable about the engine centerline 12 and couple to a plurality of rotatable elements, which can collectively define a rotor 51.

The LP compressor 24 and the HP compressor 26 respectively include a plurality of compressor stages 52, 54, in which a set of compressor blades 56, 58 rotate relative to a corresponding set of static compressor vanes 60, 62 (also called a nozzle) to compress or pressurize the stream of fluid passing through the stage. In a single compressor stage 52, 54, multiple compressor blades 56, 58 can be provided in a ring and can extend radially outwardly relative to the engine centerline 12, from a blade platform to a blade tip, while the corresponding compressor vanes 60, 62 are positioned upstream of and adjacent to the rotating blades 56, 58. It is noted that the number of blades, vanes, and compressor stages shown in FIG. 1 were selected for illustrative purposes only, and that other numbers are possible.

The blades 56, 58 for a stage of the compressor can be mounted to a compressor disk 61, which is mounted to the corresponding one of the HP and LP spools 48, 50, with each stage having its own compressor disk 61. The blades 56, 58 may be part of a blisk, rather than being mounted to a disk. The vanes 60, 62 for a stage of the compressor can be mounted to the core casing 46 in a circumferential arrangement.

The HP turbine 34 and the LP turbine 36 respectively include a plurality of turbine stages 64, 66, in which a set of turbine blades 68, 70 are rotated relative to corresponding sets of static turbine vanes 72, 74, to extract energy from the stream of fluid passing through the turbine stage 64, 66. In a single turbine stage 64, 66, multiple turbine blades 68, 70 can be provided in a ring and can extend radially outwardly relative to the engine centerline 12, from a blade platform to a blade tip, while the corresponding turbine vanes 72, 74 are positioned upstream of and adjacent to the rotating turbine blades 68, 70. The turbine blades 68, 70 and the turbine vanes 72, 74 can be airfoil shaped. It is noted that the number of blades, vanes, and turbine stages shown in FIG. 1 were selected for illustrative purposes only, and that other numbers are possible.

The turbine blades 68, 70 for a stage of the turbine can be mounted to a turbine disk 71, which is mounted to the corresponding one of the HP and LP spools 48, 50, with each stage having a dedicated turbine disk 71. The vanes 72, 74 for a stage of the compressor can be mounted to the core casing 46 in a circumferential arrangement.

Complimentary to the rotor portion, the stationary portions of the gas turbine engine 10, such as the vanes 60, 62, 72, 74 among the compressor and turbine sections 22, 32 are also referred to individually or collectively as a stator 63. As such, the stator 63 can refer to the combination of non-rotating elements throughout the gas turbine engine 10.

In operation, the airflow exiting the fan section 18 is split such that a portion of the airflow is channeled into the LP compressor 24, which then supplies pressurized airflow 76 to the HP compressor 26, which further pressurizes the air. The pressurized airflow 76 from the HP compressor 26 is mixed with fuel in the combustor 30 and ignited, thereby generating combustion gases. Some work is extracted from these gases by the HP turbine 34, which drives the HP compressor 26. The combustion gases are discharged into the LP turbine 36, which extracts additional work to drive the LP compressor 24, and the exhaust gas is ultimately discharged from the gas turbine engine 10 via the exhaust section 38. The driving of the LP turbine 36 drives the LP spool 50 to rotate the fan 20 and the LP compressor 24.

A portion of the pressurized airflow 76 can be drawn from the compressor section 22 as bypass cooling air 77, sometimes referred to as bleed air. The bypass cooling air 77 can be drawn from the pressurized airflow 76 and provided to engine components requiring cooling. The temperature of pressurized airflow 76 entering and exiting the combustor 30 is significantly increased. As such, cooling provided by the bypass cooling air 77 is supplied to downstream turbine components (e.g., a blade 68) being subjected to the heightened temperature environments.

A remaining portion of the airflow exiting the fan section, called a bypass airflow 78, bypasses the LP compressor 24 and engine core 44 and exits the gas turbine engine 10 through a stationary vane row, and more particularly an outlet guide vane assembly 80, comprising a plurality of airfoil guide vanes 82, at the fan exhaust 84. More specifically, a circumferential row of radially extending airfoil guide vanes 82 are utilized adjacent the fan section 18 to exert some directional control of the bypass airflow 78.

Some of the air supplied by the fan 20 can bypass the engine core 44 and be used for cooling of portions, especially hot portions, of the gas turbine engine 10, and/or used to cool or power other aspects of the aircraft. In the context of a turbine engine, the hot portions of the engine are normally downstream of the combustor 30, especially the turbine section 32, with the HP turbine 34 being the hottest portion as it is directly downstream of the combustion section 28. Other sources of cooling fluid can be, but are not limited to, fluid discharged from the LP compressor 24 or the HP compressor 26.

FIG. 3 depicts a block diagram of an air turbine starter system 200 in accordance with a non-limiting aspect of the present disclosure. The air turbine starter 210 can be in and/or coupled to the engine 102 of FIG. 1. The air turbine starter system 200 includes an air turbine starter 210. The air turbine starter 210 can include, in downstream serial flow relationship, a turbine motor 221, a speed reducer 231, and a clutch 241. The air turbine starter 210 is coupleable to the engine 102. For example, the clutch 241 can be arranged to selectively and rotatably engage with the rotor 51 (FIG. 2) of the engine 102, such as via a drive shaft or gearbox. The air turbine starter 210 can include a DAQ system 330 disposed thereon, communicatively coupled to a set of starter sensors 310. In some aspects, the DAQ system 330 is coupled to a housing (e.g., the housing 212 shown in FIG. 4) of the air turbine starter 210. The DAQ system 330 includes a DAQ controller 335, a power source 360, and a DAQ memory device 340. The DAQ memory device 340 can store, among other things, a set of air turbine starter operational (SO) data 345 and a set of predetermined reference data 347. In non-limiting aspects, the DAQ controller 335 can include, or be communicatively coupled to, a data analytics (DA) module 350. The starter sensors 310 can be communicatively coupled to the DAQ controller 335. The DAQ system 330 is integrated with the air turbine starter 210. For instance, the DAQ system 330 and the air turbine starter 210 can be cooperatively located within a common housing.

In non-limiting aspects, the air turbine starter system 200 can include, or be coupled to, a starter air valve 302. Optionally, in such aspects, the starter sensors 310 can include a set of valve sensors 314. The starter air valve 302 can be mechanically coupled to the air turbine starter 210. The starter air valve 302 can be communicatively coupled with the aircraft controller 106 (e.g., a FADEC). In some aspects, the aircraft controller 106 can be configured to control an operation (e.g., an opening and closing) of the starter air valve 302.

The DAQ controller 335, or DA module 350, or both, can include one or more controller modules or processors, which can run or execute any suitable programs. It will be understood that the DAQ controller 335 or DA module 350, or both, can include or be associated with any suitable number of individual microprocessors, power supplies, storage devices, interface cards, computers, controller modules, and other standard components. The DAQ controller 335 or DA module 350, or both, can include or cooperate with machine executable code, any number of software (also sometimes called “firmware”) programs (e.g., data acquisition and analysis programs), or other instructions designed to carry out the various methods, process tasks, calculations, and control/display functions necessary for operation of the DAQ system 330, or DA module 350, or both. In non-limiting aspects, the DA module 350, or DA module 350, or both, can comprise machine executable code, or software programs installed on the DAQ controller 335, or DA module 350, or both, or stored in the DAQ memory device 340. In non-limiting aspects, the DA module 350 can include a dedicated processor. The DA module 350, or DA module 350, or both, can be arranged to receive data from the DAQ memory device 340. The DAQ memory device 340 can include transition, volatile or non-transient, or non-volatile memory. In some aspects, the DAQ memory device 340 can be fixed to the air turbine starter 210. In other non-limiting aspects, the DAQ memory device 340 can be removeable (e.g., a portable memory device) from the air turbine starter 210. Additional non-limiting examples of the DAQ memory device 340 can include Random Access Memory (RAM), Read-Only Memory (ROM), flash memory, or one or more different types of portable electronic memory, such as a flash drive, Universal Serial Bus (USB) drives, and the like, or any suitable combination of these types of memory. In Additionally, the DAQ memory 340 can store various data, data types, sensed or measured data values, inputs, generated or processed data, or the like, accessible by the DAQ controller 335 in providing instruction, control, or operation to affect a functional or operable outcome, as described herein.

The DA module 350, or DA module 350, or both, is/are configured to process or perform an analysis of the data received from the DAQ memory device 340. The DA controller 335 can be configured to receive or collect data at least during an operation of the air turbine starter 210. The analysis of the data can be performed by the DA module 350 during the operation of the air turbine starter 210 (e.g., pre-flight), during a flight, post-flight, or a combination thereof.

In one non-limiting example, the executing instructions can include performing an analysis such as by a comparing of a first value with a second value, and operating or controlling operations of additional components based on the comparison. For example, when a sensed, measured, or provided value is compared with another value (e.g., a stored or predetermined value), a satisfaction of that comparison can result in actions, functions, or operations controllable by the DAQ controller 335. As used, the term “satisfies” or “satisfaction” of the comparison is used herein to mean that the first value satisfies the second value, such as being equal to or greater than the second value, or being within the value range of the second value. It will be understood that such a determination may easily be altered to be satisfied by a positive/negative comparison or a true/false comparison. Example comparisons can include comparing a sensed or measured value to a threshold value or threshold value range.

The DAQ controller 335, or DA module 350, or both, can also include a communication interface used to communicate, for example, with the other components of the DAQ system, or the aircraft controller 106, or both. The communication interface can include any suitable components for interfacing with one or more network(s), including for example, transmitters, receivers, ports, controllers, antennas, or other suitable components.

The DAQ memory device 340 is communicatively coupled to the DAQ controller 335, the DA module 350, or both. The DAQ memory device 340 can include Random Access Memory (RAM), Read-Only Memory (ROM), flash memory, and the like. In non-limiting aspects, the DAQ memory device 340 can be a portable memory device. For example, the DAQ memory device 340 can include or more different types of portable electronic memory, such as discs, Digital Versatile disks (DVD), Compact Disc-Read-Only Memory (CD-ROMs), etc., or any suitable combination of these types of memory. The DAQ memory device 340 can store various data, data types, sensed or measured data values, inputs, generated or processed data, or the like, accessible by the DAQ controller 335, or the DA module 350, or both in providing instruction, control, analysis, computation, or operation to effect a functional or operable outcome, as described herein.

For example, the DAQ memory device 340 can store the SO data 345 and reference data 347 accessible by the DAQ controller 335, or the DA module 350, or both. The SO data 345 can include data sensed by the starter sensors 310 or set of valve sensors 314 and any other data associated with aircraft 100, as described herein. The SO data 345 and predetermined reference data 347 can include one or more table(s), function(s), algorithm(s), model(s), equation(s), etc. for use by the DAQ controller 335 or DA module 350 or both.

The set of starter sensors 310 can include any number of starter sensors 310 arranged in signal communication with the DAQ controller 335. The set of starter sensors 310 can be configured to measure, detect, or otherwise sense a respective predetermined operating parameter of the air turbine starter 210. The set of starter sensors 310 are further configured to provide respective starter sensor signals 311 indicative of a respective value (e.g., a magnitude, a frequency, a count, etc.) of the sensed operating parameter (e.g., a temperature, a force, etc.) associated with the air turbine starter 210 to the DAQ controller 335. For example, a particular starter sensor 310 can be arranged to provide a respective starter sensor signal 311 indicative of a parameter (e.g., a temperature) associated with a bearing within the housing 212 of the air turbine starter 210. In another instance, a particular starter sensor 310 can provide a respective starter sensor signal 311 indicative of a frequency (e.g., indicative of a vibration) associated with the bearing. The values of the sensed parameters can be indicative of a condition or operational performance of the air turbine starter 210. The set of starter sensors 310 can include any desired sensing device including, without limitation, an accelerometer, a thermocouple, a motion sensor, a microphone, a force sensor, a pressure sensor, a proximity sensor, a counter, and the like, or combinations thereof. The set of starter sensors 310 can be selected and arranged to measure or sense any desired parameter, including, without limitation, mechanical vibration, mechanical force, rotational speed, acceleration, temperature, vibration, force, pressure, frequency, sound, number of operations, and the like, or combinations thereof.

The set of valve sensors 314 can include any number of valve sensors 314 arranged in signal communication with the DAQ controller 335, the aircraft controller 106, or both. The set of valve sensors 314 can be configured to measure, detect, or otherwise sense a respective predetermined parameter. The set of valve sensors 314 can be further configured to provide respective valve sensor signals 315 indicative of a respective value of the sensed parameter to the DAQ controller 335, or the aircraft controller 106, or both. The set of valve sensors 314 can include, for example, a pressure gauge, a vacuum gauge, a manometer, and the like, or combination thereof. The set of valve sensors 314 can measure pressure or temperature, or both. The measured pressure and/or temperature can be indicative of a condition of the starter air valve 302. Collectively, the values indicated by the valve sensor signals 315, or the valve sensor signal 315, or both, can define the SO data 345.

It will be appreciated that the foregoing exemplary listing of starter sensors 310 and valve sensors 314 is given by way of example, and other aspects are not so limited. In various other aspects, any number of starter sensors 310 and valve sensors 314 can be arranged and disposed to provide a respective starter sensor signal 311, and valve sensor signal 315 that is indicative of any desired parameter without departing from the scope of the disclosure herein.

The power source 360 is electrically coupled to the DAQ controller 335, the DA module 350, or the DAQ memory device 340, or combinations thereof, and configured to provide electrical power thereto. The power source 360 can be a limited supply power source. As used herein, a “limited supply power source” includes any power source that is limited in supplying an amount or quantity of power over a period of time by way of, for example, a discharge cycle of operation. The power source 360 can include, but is not limited to, fuel cell systems, hydrogen cell systems, capacitors, super capacitors, battery systems, rechargeable systems such as solar or photovoltaic cells, banks of any of the preceding examples, or combinations thereof.

Additionally, or alternatively, in non-limiting aspects, the power source 360 can be a constant power source. As used herein, a “constant power source” includes power sources that are capable or configured to generate a predicted or predetermined quantity of power during expected operation. In one non-limiting example, the power source 360 can include an electrical generator or generator system that generates electrical power in response to kinetic motion (e.g., a rotation of a shaft)). In some non-limiting aspects, the generator can include an eddy current generator.

In operation, the aircraft controller 106 can control an operation of the air turbine starter 210. For example, the aircraft controller 106 can control a rate of opening, or a percentage open, or both, of the starter air valve 302. The starter air valve 302 controls the flow of a fluid (e.g., pressurized air) to the turbine motor 221. The higher percentage the controller is open, the more fluid can be provided to the air turbine starter 210. For example, the aircraft controller 106 can cause the starter air valve 302 to open and shut at a rate of twice per second, or any other rate. In another non-limiting instance, the aircraft controller 106 can cause the starter air valve 302 to selectively operate between a fully closed state (e.g., 0% open) to a fully open state (e.g., 100% open), or at any other desired percentage open (e.g., between 0% and 100% open). Changing the rate of opening and/or the percentage open of the starter air valve 302 can modify the fluid provided to the air turbine starter 210 from the starter air valve 302.

With simultaneous reference to FIG. 2 and FIG. 3, in an operation of the air turbine starter system 200, the starter air valve 302 can receive a command signal 107 from the aircraft controller 106. The starter air valve 302 can regulate a fluid flow 307 (e.g., an air flow) to the turbine motor 221 based on the command signal 107. For example, in one non-limiting instance, the fluid flow 307 can be supplied as bleed air from an auxiliary power unit (APU) of the engine 102. In other instances, the fluid flow 307 can be provided as cross-bleed air from another engine on the aircraft 10. In still other instances, the fluid flow 307 can be provided from a stored air cart (sometimes called a “start cart”) separate from the aircraft 10. Regardless of the source of the fluid flow 307, the air turbine starter 210 converts energy from the fluid flow 307 provided to the air turbine starter 210 from the starter air valve 302 to a torque output usable for starting the engine 102. For example, the turbine motor 221 can convert energy from the fluid flow 307 supplied by the starter air valve 302 to a high-speed rotation energy. The speed reducer 231 converts the rotation energy (e.g., high speed, low torque) from the turbine motor 221 into lower speed, (e.g., low-speed, high torque) rotation energy used to rotate the clutch 241. The rotating clutch 241 is used to engage with and drive a rotation of the engine 102. For example, in one particular instance, the clutch 241 is selectively engageable with the rotor 51 of the engine 102 via a drive shaft rotatably coupled to an accessory gearbox. As the air turbine starter 210 drives a rotation of the engine 102, fuel is added to the combustor 30 and ignited thereby generating combustion gases which further drive the rotation of the engine 102. The air turbine starter 210 cooperatively continues to drive the rotation of the engine 102 until a predetermined rotational speed (e.g., 4000 revolutions per minute) sometimes called a “cut-out speed” of the rotor 51 is reached. When the engine 102 is started and the rotor 51 attains the predetermined rotational speed, the clutch 241 disengages from the engine 102 and the starter air valve 302 receives another command signal 107 from the aircraft controller 106 to cut off the fluid flow 307 to the air turbine starter 210.

During an operation of the DAQ 330, the power source 360 provides operating power to the DAQ controller 335 or the DAQ memory device 340, or both. The DAQ controller 335 receives or collects data related to an operation of the air turbine starter 210 from the set of starter sensors 310, the valve sensors 314, or both. For example, the set of starter sensors 310 provide the respective starter sensor signals 311 indicative of the value of the respective sensed parameters to the DAQ controller 335. The DAQ controller 335 stores the values indicated by the starter sensor signals 311 in the DAQ memory device 340. The set of valve sensors 314 provide the respective valve sensor signals 315 indicative of the value of the respective sensed parameters to the DAQ controller 335, or the aircraft controller 106, or both. The DAQ controller 335 stores the values indicated by the valve sensor signals 315 in the DAQ memory device 340. The values indicated by the starter sensor signals 311, or the valve sensor signals 315, or both, are stored in the DAQ memory device 340 and define the SO data 345.

In non-limiting aspects, the DA module 350 can perform an analysis of the SO data 345. The analysis can be conducted by the DA module 350 during an operation of the air turbine starter 210. Additionally, or alternatively, the analysis can be conducted by the DA module 350 during a flight (e.g., when the clutch 241 is disengaged from the engine 102. In non-limiting aspects, the analysis can also be conducted by the module 350, or another computing device as desired post-flight, for example during a maintenance or service operation on the air turbine starter 210.

In some aspects, the analysis can include a comparison of one or more values indicated by the starter sensor signals 311, or the valve sensor signals 315, or both, to a predetermined threshold value. In some aspects, the analysis can include determining one or more trends over time in the values indicated by the starter sensor signals 311, or the valve sensor signals 315, or both. The analysis can further include a comparison of the determined trend over time to a predetermined trend threshold. For example, the analysis can include tracking deviations of a particular parameter over time from a predetermined trend threshold. The analysis can further include a prediction of a future value of a particular parameter. The analysis can still further include a comparison of the predicted future value of the particular parameter to a predetermined threshold. In some aspects, the analysis can include correlating the values indicated by the starter sensor signals 311, or the valve sensor signals 315, or both, to each other (e.g., correlating a temperature of the air turbine starter 210 to a number of operations of the starter 210).

Based on the analysis, the DA module 350, or the DAQ controller 335, or both, can determine the presence of an undesired condition or anomaly (e.g., as indicated by an operating parameter having a value that satisfies a threshold value or range), or predict a future presence of an undesired condition or anomaly. The determined anomaly can originate from the air turbine starter 210, starter air valve 302, engine 102, or combinations thereof. For example, in one instance, the anomaly can be an irregular movement of the rotating portion (e.g., the turbine motor 221) of the air turbine starter 210 indicated by measured mechanical vibration and/or sound. This anomaly or irregularity can be indicative of a fault of a part of the air turbine starter 210. In some instances, this anomaly or irregularity can be indicative of a predicted or future fault of a part of the air turbine starter 210. In response to the determined irregular movement of the rotating portion of the air turbine starter 210, the DAQ controller 335 can provide an alert or notification 317 indicative of the anomaly with the air turbine starter 210, starter air valve 302, engine 102, or combinations thereof. The notification 317 can be provided to the aircraft controller 106. In non-limiting aspects, the aircraft controller 106 can provide a display indicative of the notification 317 on a user interface device (e.g., a screen in a cockpit of the aircraft 100).

In another non-limiting example, in one particular aspect, the DA module 350 can determine, based on the SO data 345, or a subset thereof, a current temperature of the turbine motor 221. The DA module 350 can further analyze the SO data 345 by performing an analysis including a comparison of the determined current temperature with predetermined reference data 347. In non-limiting aspects, for example, the predetermined reference data 347 can include a predetermined threshold temperature value. The predetermined threshold temperature value can be based on, without limitation, a set of predetermined operating conditions or parameters, data saved in the DAQ memory device 340, calculated values, or combinations thereof. Based on the comparison of the of the determined current temperature with the predetermined reference value, the DA module 350 can determine whether the determined current temperature of the turbine motor 221 satisfies the predetermined threshold. In the event that the determined current temperature of the turbine motor 221 satisfies the predetermined threshold, the DAQ controller 335 can be configured to trigger an alert or notification 317 to the aircraft controller 106 to indicate the current temperature of the turbine motor 221 does not satisfy the predetermined threshold. In non-limiting aspects, the aircraft controller 106 can provide a display indicative of the notification 317 on a user interface device.

Additionally, or alternatively, in the event that the DA module 350 determines the presence of an undesired condition or anomaly (e.g., as indicated by an operating parameter having a value that satisfies a threshold value or range), the DA module 350 can provide an indication of the determination to be stored in the DAQ memory device 340.

In non-limiting aspects, the DAQ memory device 340 can be a portable or removeable type memory device. In such aspects, the DAQ memory device 340 is removeable from the air turbine starter 210, and a post-flight analysis of the SO data 345 can be conducted using a separate or remote computing device configured to read and/or upload the SO data 345 from the portable DAQ memory device 340 device for analysis. In other non-limiting aspects the DAQ memory device 340 can be non-removeable from the air turbine starter 210.

The numerical examples provided herein are provided for purposes of illustration and discussion and are not intended to be limiting of the present disclosure.

FIG. 4 shows an exemplary air turbine starter 210 in cross section, in accordance with a non-limiting aspect. The air turbine starter 210 has a housing 212 defining a housing interior 213. Within the housing interior 213, the housing 212 includes a turbine section 220, a speed reducer section 230, and a clutch section 240. The air turbine starter 210 integrates the DAQ system 330, communicatively coupled to the set of starter sensors 310. The DAQ system 330 includes the DAQ controller 335, the power source 360, and the DAQ memory device 340. In non-limiting aspects, the DAQ system 330 can include the DA module (shown in FIG. 3).

The housing 212 defines a flow path 214 extending from an air inlet 216 fluidly coupled to an intake plenum 216a through the turbine section 220, to an exhaust duct 218 fluidly coupled to an exhaust outlet 219. In non-limiting aspects, a portion of the flow path 214 can be an annular portion. The housing 212 includes a mounting flange 212a for mounting the air turbine starter 210 to an aircraft engine 102 (FIG. 2). An air duct 215 is coupled to the air inlet 216. The air duct 215 receives the fluid flow 307 (indicated by dashed arrows) from the starter air valve 302 (shown in FIG. 3). In other aspects, the fluid flow 307 can be from another supply.

Within the turbine section 220, the housing 212 can define the exhaust duct 218 as part of the flow path 214 downstream of the air inlet 216, and fluidly coupled to the exhaust outlet 219. The turbine section 220 can include the turbine motor 221. The turbine motor 221 includes a turbine wheel 222 coupled to a rotatable turbine shaft 224 extending therefrom. The turbine shaft 224 can be journaled by bearings 226 to the housing 212. A pinion gear 225 is coupled to the turbine shaft 224 to rotate therewith. A set of turbine blades 223 are circumferentially mounted to the turbine wheel 222 and rotatably disposed within the flow path 214. A set of non-rotatable nozzles 229 are coupled to the housing 212 within the air flow path 214 upstream of, and in fluid communication with, the turbine blades. The exhaust duct 218 is arranged downstream of the turbine motor 221 to receive the fluid flow 307 therefrom.

The speed reducer section 230 can include a speed reducer 231 such as a gear train. For example, in non-limiting aspects, the gear train can be a compound planetary gear train including a set of shafts each having a respective gear arranged to mesh with the pinion gear 225. The speed reducer 231 is rotatably coupled to the turbine shaft 224.

The clutch section 240 can include the clutch 241. The clutch 241 can include an input side 241a and an output side 241b. In non-limiting aspects, the clutch 241 can be an overrunning clutch such as a pawl and ratchet type clutch. The clutch 241 is rotatably coupled to the speed reducer 231 at the input side 241a, and is coupled to a clutch drive shaft 245 at the output side 241b. The clutch drive shaft 245 can extend beyond the housing 212. An air turbine starter output shaft 250 is coupled to the clutch drive shaft 245. The air turbine starter output shaft 250 can be coupled, for example, to a starter pad or gearbox, of the gas turbine engine (FIGS. 1 and 2).

In some aspects, the DAQ controller 335 and the DAQ memory device 340 are coupled to the housing 212 (e.g., on an inner surface of the housing 212, or on outer surface of the housing 212). In non-limiting aspects, the DAQ controller 335, the DAQ memory device 340, or both, can be disposed or contained within a DAQ enclosure 344 mounted on or fastened to the housing 212. In non-limiting aspects, the DAQ enclosure 344 can be fastened to the housing 212 via threaded fasteners. In other aspects, the DAQ enclosure 344 can be fastened using an adhesive. In still other aspects, the DAQ enclosure 344 can be formed as part of the housing 212. In some aspects, the DAQ enclosure 344 is coupled to an exterior surface of the housing 212. In still other aspects, the DAQ enclosure 344 can be mounted to any desired part of the air turbine starter 210. In some aspects, the DAQ enclosure 344 can be coupled to an inner surface of the housing 212 and disposed in the housing interior 213. For example, as illustrated, the DAQ enclosure 344 can be located within the exhaust duct 218. In non-limiting aspects, the DAQ enclosure 344 can include a thermally insulative layer 349 surrounding the DAQ controller 335, the DAQ memory device 340, or both. The thermally insulative layer 349 can surround the DAQ enclosure 344 or a portion thereof. In some aspects, the thermally insulative layer can be arranged on an exterior of the DAQ enclosure 344. In other aspects, the thermally insulative layer 349 can be disposed on an interior of the DAQ enclosure 344. In non-limiting aspects, the thermally insulative layer 349 can be integrated with the DAQ enclosure 344.

The DAQ controller 335 is communicatively coupled to the set of starter sensors 310 to receive the sensor signals 311 (shown in FIG. 3) therefrom. The set of starter sensors 310 can be located as desired on the air turbine starter 210. For example, in non-limiting aspects, at least one starter sensor 310 can be disposed on a stationary portion (e.g., the housing 212) of the air turbine starter 210 to monitor a rotating portion (e.g., the pinion gear 225) of the air turbine starter 210. In another non-limiting aspect, at least one starter sensor 310 can be disposed on a rotating portion (e.g., the pinion gear 225) of the air turbine starter 210 to monitor the rotating portion of the air turbine starter 210.

In operation, the air duct 215 can convey the fluid flow 307 to the flow path 214 in the housing interior 213 via the air inlet 216. In non-limiting aspects, pressure of the fluid flow 307 at the air inlet 216 can be in the range of 30-55 pounds per square inch gauge (psig), and the temperature of the fluid flow 307 at the air inlet 216 can be in the range of 300-400 degrees Fahrenheit (F). In other aspects, the air pressure and temperature of the fluid flow 307 at the air inlet