Example implementations relate to jet engines that include resonator-based diagnostics. An example implementation includes a jet engine. The jet engine includes a combustion chamber configured to house a combustion event of a fuel mixture. The jet engine also includes a resonator having a characteristic impedance and a resonant wavelength. The resonator includes a first conductor and a second conductor separated from one another by an interstitial space that is exposed to an environment of the combustion chamber. Further, the jet engine includes a controller communicatively coupled to the resonator and configured to perform operations. The operations include determining a characteristic of the resonator selected from the group consisting of the characteristic impedance and the resonant wavelength. The operations also include, based on the determined characteristic, determining a parameter of the combustion chamber.

Systems and methods for detecting inclement weather in the vicinity of an aircraft engine are described herein. At least a first engine parameter and a second engine parameter are obtained, each engine parameter varies with changing weather conditions. An arithmetic value is determined as a function of at least the first engine parameter and the second engine parameter. The arithmetic value varies with changing weather conditions. A rate of change of the arithmetic value is determined. Inclement weather is detected when the rate of change exceeds a threshold.

An example turbofan engine starting system includes a core nacelle housing a compressor and a turbine. The core nacelle is disposed within a fan nacelle. The fan nacelle includes a turbofan. A bypass flow path downstream from the turbofan is arranged between the two nacelles. A controller is programmed to manipulate the nozzle exit area to facilitate startup of the engine. In one example, manipulates the nozzle exit area using nozzles, in response to an engine shutdown condition. The nozzles open and close to adjust the nozzle exit area.

A method and system for determining one or more precursors to control blowout in a combustor is provided. The method includes obtaining a time series signal corresponding to a dynamic state variable of the combustor. The method includes detecting one or more precursor based on an analysis of the time series signal using one or more parameters to control blowout in the combustor. One or more parameters include a Hurst exponent estimation, a Burst count estimation, and a recurrence quantification based estimation.

There is disclosed an aero gas turbine engine comprising a compressor and an array of variable inlet guide vanes for the compressor. The angle of the variable inlet guide vanes is controlled by scheduling, the scheduling comprising a first component invoked for engine ground start and a second component invoked for engine in-flight windmill start at least under particular flight conditions. The angle of the variable inlet guide vanes required by at least a portion of the second component is greater than the angle of the variable inlet guide vanes required by at least a portion of the first component.

The invention relates to an overspeed protection device of an aircraft engine.

There is described a method and system for in-flight start of an engine. The method comprises rotating a propeller; generating electrical power at an electric generator embedded inside a propeller hub from rotation of the propeller; transmitting the electrical power from the electric generator to an engine starter mounted on a core of the engine via an electric power link; and driving the engine with the engine starter to a sufficient speed while providing fuel to a combustor to light the engine to achieve self-sustaining operation of the engine.

A propulsion system includes a gas turbine designed so that a combustion chamber can be ignited in a first ignition range of rotational speeds of a compressor shaft. The system further includes a control device designed to control an electric starter to accelerate the compressor shaft and, when the compressor shaft is accelerated, to control an attempt to ignite the combustion chamber. The gas turbine is designed so that the combustion chamber can be ignited in a second ignition range which is higher than the first ignition range, but not between these two ignition ranges, and the ignition attempt is carried out in the second ignition range.

A system for automated management of in-flight restarting of engines of an aircraft includes controllers, each engine of the aircraft being managed by one of the controllers. A controller that detects an engine that has stopped: cuts off the energy supply of the engine and performs a windmill engine start. If at least one other engine has stopped, prioritization of engine restarting includes: collecting information concerning a state of health of each engine; determining from the information collected information representing a probability of restarting each stopped engine; determining a sequential order of restarting the stopped engines as a function of information representing the probability of restarting each stopped engine. Each stopped engine continues to be windmill started until selection of the engine in question in the sequential order of restarting the stopped engines. Thus, the operational status of the aircraft is improved as quickly as possible.

A system for controlling an operation of a combustor in a gas turbine that includes: an acoustic sensor configured to periodically measure a pressure of the combustor and generate a raw data stream having the pressure data points resulting from the periodic measurements; and a blowout detection unit configured to receive the raw data stream from the acoustic sensor. The blowout detection unit may include a processor and a machine-readable storage medium on which is stored instructions that cause the processor to execute a procedure related to a detection of a blowout precursor. The procedure may include an ensemble approach in which the detection of the blowout precursor depends upon a outcomes generated respectively by separate detection analytics.