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 gas turbine engine may include a fuel manifold extending circumferentially around a diffuser case of the gas turbine engine. The fuel manifold may include a fuel supply inlet interface for receiving fuel into the fuel manifold and a plurality of fuel delivery outlet interfaces for delivering fuel to a combustor of the gas turbine engine. The gas turbine engine may also include a valve coupled to the fuel manifold. The valve may be configured to control fuel distribution in the fuel manifold. The valve may be disposed between two fuel delivery outlet interfaces of the plurality of fuel delivery outlet interfaces. The valve may be configured to at least decrease fuel flow to one of the plurality of fuel delivery outlet interfaces. The valve may be configured to at least decrease fuel flow to half of the plurality of fuel delivery outlet interfaces.

A method for monitoring the change in state of a valve in a start up circuit of a turbo-engine following a command to change the state of the valve includes measuring the air pressure under a fan cowl of the turbo-engine before the change state command, measuring the air pressure under the fan cowl after the change state command, comparing the measured values of the air pressure, and determining whether or not the valve has actually changed state. An aircraft turbo-engine includes a unit that monitors the change in the valve using such a method.

The invention deals with the restriction on the mode change of an engine due to latching in the case of restarting the engine that has stopped in flight. A FADEC that controls an engine of an aircraft in accordance with a mode, includes a latch operating section that latches the mode, and an in-parking/in-flight determining section that determines whether the aircraft is on the ground or flying off the ground. The latch operating section operates when the in-parking/in-flight determining section determines the aircraft is on the ground, and does not operate when the in-parking/in-flight determining section determines that the aircraft is in fight.

The method allows to detect flameout in a combustor of a turbine system; it comprises the steps of: A) measuring angular acceleration of a shaft of the or each turbine of the turbine system, B) calculating a flameout indicator as a function of the angular acceleration, and C) carrying out a comparison between the flameout indicator and at least one threshold.

A method for predicting a combustion error type of a combustion flame. A raw signal of an error parameter of the combustion flame within a predefined time span is measured, the error parameter is adapted for determining the combustion error type. A predefined frequency range from the raw signal is extracted using a by-pass filter, where the raw signal is decomposed. The number of peaks of the predefined frequency range within the time span is counted. An actual reference value is determined by dividing the number of counted peaks by the time span. The actual reference value is compared with a nominal reference value, wherein the nominal reference value is determined by dividing a predefined number of peaks of the predefined frequency range by the time span, so that the combustion error type is predictable if the actual reference value differs to the nominal reference value.

A method of starting a gas turbine engine includes determining an abnormal shutdown condition during operation of the gas turbine engine and determining a first set of lightoff parameters for the gas turbine engine. The method also includes restarting the gas turbine engine using the first set of lightoff parameters. The method further includes iteratively determining subsequent first sets of lightoff parameters and restarting the gas turbine engine using a respective subsequent first set of the determined subsequent first sets of lightoff parameters until the gas turbine maintains a first set of operational parameters, where the first set of operational parameters is representative of a robust lightoff of the gas turbine engine.

A system includes a control system. The control system includes a coherence derivation system configured to derive a coherence between respective outputs of each of a plurality of combustors coupled to a gas turbine system, and a phase derivation system configured to derive a phase difference between the respective outputs of each of the plurality of combustors coupled to the gas turbine system. The control system is configured to derive an indication of an impending lean blowout (LBO) or an actual LBO of at least one of the plurality of combustors based at least in part on the coherence derivation, the phase derivation, or a combination thereof.

An example system includes a first gas-turbine engine configured to propel an aircraft, the first gas-turbine engine comprising a first electric starter, the first electric starter configured to rotate a spool of the first gas-turbine engine; and one or more controllers collectively configured to: cause, following operation of the first gas-turbine engine, the first electric starter to perform barring of the first gas-turbine engine; measure, during the barring of the first gas-turbine engine, values of one or more parameters of the first gas-turbine engine; and determine, based on the values of the one or more parameters, whether the first electric starter is available for use in performing mid-air restart of the first gas-turbine engine.

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