Abstract: A method for positioning sensors about a sensor ring includes the steps of assigning each sensor in a plurality of sensors a sensor number selected from a set of sensor numbers, where the set of sensor numbers is a whole number in the range of 0 to N, and where N is the total number of sensors in said plurality of sensors minus one, disposing a first sensor at a circumferential angular position zero on the sensor ring, and disposing each sensor in the plurality of sensors at a circumferential angular position about the sensor ring, wherein the circumferential angular position is defined by an offset from a circumferential angular position zero and the offset is equal to a base arc length between sensors multiplied by the sensor number of the sensor plus a base offset arc length multiplied by the sensor number of the sensor.

Abstract: A method of powering a rotary-wing aircraft includes selectively coupling and uncoupling a first power turbine to change a power distribution between the rotor system and the secondary propulsion system.

Abstract: An example aircraft debris monitoring sensor assembly includes an aircraft conduit defining a hollow core passage extending axially from an inlet opening to an outlet opening. A sensor arrangement detects debris carried by a fluid within the hollow core passage.

Abstract: A method for positioning sensors about a sensor ring includes the steps of assigning each sensor in a plurality of sensors a sensor number selected from a set of sensor numbers, where the set of sensor numbers is a whole number in the range of 0 to N, and where N is the total number of sensors in said plurality of sensors minus one, disposing a first sensor at a circumferential angular position zero on the sensor ring, and disposing each sensor in the plurality of sensors at a circumferential angular position about the sensor ring, wherein the circumferential angular position is defined by an offset from a circumferential angular position zero and the offset is equal to a base arc length between sensors multiplied by the sensor number of the sensor plus a base offset arc length multiplied by the sensor number of the sensor.

Abstract: A rotary-wing aircraft includes a retractable port movable between a closed position and an open position to selectively control flow of combustion gases into a bypass passage to change a power distribution between a rotor system and a secondary propulsion system.

Abstract: A turbine engine section has a stationary vane stage and a rotating blade stage. The blade stage is spaced from the vane stage to form an annular chamber therebetween. A manifold delivers a pressurized fluid to the chamber. An outer diameter (OD) sealing system restricts leakage of the pressurized fluid from the chamber. An inner diameter (ID) sealing system restricts leakage of the pressurized fluid from the chamber. A flow guide extends radially between the inner diameter sealing system and the manifold. The flow guide bisects the chamber to form a stationary chamber portion and a rotating chamber portion, the rotating chamber portion at least partially along a disk of the first blade stage.

Abstract: A convertible gas turbine propulsion system operates in multiple output modes. The convertible gas turbine propulsion system comprises a gas generator, a first power turbine, a secondary propulsion system and an exhaust duct. The gas generator is configured to produce exhaust gas. The first power turbine is aligned with the gas generator to receive the exhaust gas. The secondary propulsion system is in series with the gas generator and the first power turbine. The exhaust duct coaxially extends from the first power turbine to the secondary propulsion system. The exhaust duct includes an exhaust port for opening the exhaust duct to ambient air pressure and permitting exhaust gas to bypass the secondary propulsion system. In various embodiments of the invention, the first power turbine is connected to a first rotary propulsion system, and the secondary propulsion system comprises a second power turbine or a nozzle.

Abstract: A method for operating a debris monitoring system comprises continuously sensing the passage of particulates through a gas turbine engine to produce a time-domain sensor signal. The time-domain sensor signal is Fourier transformed to produce a frequency domain sensor signal. The frequency domain sensor signal is partitioned into bins corresponding to particulate composition categories. At least one feature is identified within each bin, and is used to determine the amount of particulate flow in each particulate composition category.

Abstract: A gas turbine engine system includes an air inlet, an inlet particle separator located at the air inlet and having a blower selectively driven by a variable output motor, and a controller for dynamically controlling the variable output motor that selectively drives the blower of the inlet particle separator.

Abstract: An example aircraft debris monitoring sensor assembly includes an aircraft conduit defining a hollow core passage extending axially from an inlet opening to an outlet opening. A sensor arrangement detects debris carried by a fluid within the hollow core passage.

Abstract: A method for operating a debris monitoring system comprises continuously sensing the passage of particulates through a gas turbine engine to produce a time-domain sensor signal. The time-domain sensor signal is Fourier transformed to produce a frequency domain sensor signal. The frequency domain sensor signal is partitioned into bins corresponding to particulate composition categories. At least one feature is identified within each bin, and is used to determine the amount of particulate flow in each particulate composition category.

Abstract: An example method of controlling gas turbine engine debris monitoring sensors includes detecting debris carried by air moving through an engine using at least first and second debris sensors, and processing signals from both the first and second debris sensors using a common signal conditioning unit. Another example method of monitoring gas turbine engine debris includes configuring at least one first debris sensor to detect debris carried by airflow moving through a first portion of an engine and configuring at least one second debris sensor to detect debris carried by airflow moving though a second portion of the engine. The method alternates between using the first debris sensor to detect debris and using the second debris sensor to detect debris.

Abstract: An example method of estimating gas turbine engine performance deterioration includes monitoring debris in at least a portion of an engine and estimating performance deterioration of at least one component of the engine using information from the monitoring. The method may use gas path parameters, such as pressures, temperatures, and speeds to establish the estimated performance deterioration. An example gas turbine engine performance assessment system includes a debris monitoring system configured to monitor debris moving through a portion of an engine and a controller programmed to estimate performance deterioration of at least one component of the engine based on information from the debris monitoring system.

Abstract: A method of powering a rotary-wing aircraft includes selectively coupling and uncoupling a first power turbine to change a power distribution between the rotor system and the secondary propulsion system.

Abstract: A rotary-wing aircraft includes a retractable port movable between a closed position and an open position to selectively control flow of combustion gases into a bypass passage to change a power distribution between a rotor system and a secondary propulsion system.

Abstract: An example method of assessing a component of a gas turbine engine includes monitoring debris in at least a portion of an engine and establishing an estimated thermal energy level for a component of the engine based on the monitoring. The method may use gas path parameters to establish the estimated thermal energy level. An example gas turbine engine component assessment system includes a debris monitoring system configured to monitor debris moving through a portion of an engine and a controller programmed to execute an engine deterioration model that assesses a thermal energy level of at least one component of the engine based on information from the debris monitoring system.

Abstract: An actuation mechanism for use in a convertible gas turbine propulsion system comprises a plenum, a pneumatically powered drive body and a spring system. The plenum receives pressurized air from the convertible gas turbine propulsion system. The pneumatically powered drive body is connected to the plenum to receive pressurized air to axially move the drive body in a first direction. The spring system is connected to the drive body to axially move the drive body in a second direction.

Abstract: A turbine blade damper-seal assembly includes a seal nested within a damper such that both the seal and damper are disposed to provide sealing between adjacent blade platforms. The seal traverses the seal slot in the damper and seals the gap between adjacent blade platforms for the full axial length of the neck cavity between adjacent blades. The damper is located in an aft most position and includes features to facilitate vibration-dampening performance. The damper also includes features that cause entrapment between blades and therefore avoids the conventionally required protrusions on the blade to retain it in the assembled position.

Abstract: A gas turbine engine system includes an air inlet, an inlet particle separator located at the air inlet and having a blower selectively driven by a variable output motor, and a controller for dynamically controlling the variable output motor that selectively drives the blower of the inlet particle separator.

Abstract: An example method of controlling gas turbine engine debris monitoring sensors includes detecting debris carried by air moving through an engine using at least first and second debris sensors, and processing signals from both the first and second debris sensors using a common signal conditioning unit. Another example method of monitoring gas turbine engine debris includes configuring at least one first debris sensor to detect debris carried by airflow moving through a first portion of an engine and configuring at least one second debris sensor to detect debris carried by airflow moving though a second portion of the engine. The method alternates between using the first debris sensor to detect debris and using the second debris sensor to detect debris.