A gas turbine engine including a compressor, a combustor fluidly connected to the compressor via a primary flowpath, a turbine fluidly connected to the combustor via the primary flowpath, an engine controller communicatively coupled to at least one sensor in the gas turbine engine, the controller including a non-transitory memory and a processor, and the at least one sensor including an inlet temperature and/or pressure sensor, wherein the sensor is disposed aft of a fan.

A method and a system for synthesizing thrust from a turbofan engine are provided. The turbofan engine comprising a compressor section, a combustor, and a turbine section in serial fluid flow communication. The engine is operated and, during the operating of the turbofan engine, a pressure of fluid at an exit of the compressor section and a temperature of fluid at a location upstream of the exit of the compressor section are determined. A synthesized value of thrust from the turbofan engine is determined based on a product of at least a first factor and a second factor, the first factor being a function of the pressure and the second factor being a function of the temperature. The synthesized value of thrust from the turbofan engine is output.

A gas turbine engine starting system including an electric start generator (ESG) free of temperature sensors and configured to provide torque to a gas turbine engine. A fuel metering module is configured to provide a quantity of fuel to the gas turbine engine, and an electronic control system (ECS). The ESG includes a plurality of subcomponents. The ECS is configured to predict a future temperature of the ESG, predict that at an ongoing start or an uninitiated start will be unsuccessful, and provide the prediction that at an ongoing start or an uninitiated start will be unsuccessful to an operator. The prediction of the future temperature of the ESG is based on a plurality of historical ESG thermal trending information and an input ambient temperature. The prediction that at an ongoing start or an uninitiated start will be unsuccessful is based on the future temperature of the ESG.

A control system for a variable area fan nozzle (VAFN) is disclosed. The VAFN may have a plurality of petals and may be for use with a gas turbine engine. The control system may include a primary system configured to acquire primary data indicative of an operating condition of the VAFN, a secondary system configured to acquire secondary data indicative of a current operating condition of the gas turbine engine, and a control module in operative communication with the primary system and the secondary system. The control module may be configured to: determine a nozzle area of the VAFN based at least in part on the primary data, adjust the determined nozzle area based on the secondary data, and position the plurality of petals according to the adjusted nozzle area.

According to an aspect, a correction factor for a fuel flow of a fuel system of an engine is determined. A nominal fuel flow is determined based on a metering valve stroke. The correction factor is applied to the nominal fuel flow to produce an estimated fuel flow to control combustion in the engine.

A method includes obtaining a first test matrix for a first aircraft system and a second test matrix for a second aircraft system. The method also includes, during a first operational test of the first test matrix, obtaining sensor data that includes second sensor data that is not specified by the first test matrix. The method includes evaluating a second operational test of the second test matrix by processing the second sensor data using a second analytic model of the second aircraft system. The method also includes generating second predicted sensor data based on the evaluation of the second operational test. The method includes generating a second error measure by comparing a second subset of the sensor data to the second predicted sensor data. The method includes determining, based at least in part on a range of the second sensor data, a test coverage metric of the second test matrix.

The invention relates to a method for measuring the flow rate of cooling air in a cooling air circuit (13) of a casing (121) of a high-pressure turbine (9) of a turbomachine (1). The invention is characterized in that sensors (21, 22, 24, 26, 28) are used to measure a total pressure at the fan inlet, a static pressure at the outlet of the high-pressure compressor (6), a rotational speed of the low-pressure shaft (101), a rotational speed of the high-pressure shaft (91) and a degree of valve opening of the cooling air circuit (13), a calculation unit is used to calculate the flow rate of cooling air on the basis of at least the measurement of these.

A method and system for establishing sets of blade frequency values for each rotating blade of a rotor assembly at two or more different points in time and determining an indication of blade health from the change in the blade frequency values is provided. Blade frequency values are determined by receiving measurements of vibratory responses from blade monitoring equipment (20) and processing via a processing device (30) vibration data as a system of rotating blades to extract a frequency of each blade. Sets of blade frequency values are compared to determine a change in the blade frequency values for each rotating blade to provide the indication of blade health.

A system for starting a gas turbine engine of an aircraft is provided. The system includes a pneumatic starter motor, a discrete starter valve switchable between an on-state and an off-state, and a controller operable to perform a starting sequence for the gas turbine engine. The starting sequence includes alternating on and off commands to an electromechanical device coupled to the discrete starter valve to achieve a partially open position of the discrete starter valve to control a flow from a starter air supply to the pneumatic starter motor to drive rotation of a starting spool of the gas turbine engine below an engine idle speed.

In an embodiment, a system includes a gas turbine controller. The gas turbine controller is configured to receive a plurality of sensor signals from a fuel composition sensor, a pressure sensor, a temperature sensor, a flow sensor, or a combination thereof, included in a gas turbine engine system. The controller is further configured to execute a gas turbine model by applying the plurality of sensor signals as input to derive a plurality of estimated gas turbine engine parameters. The controller is also configured to execute a flame holding model by applying the plurality of sensor signals and the plurality of estimated gas turbine engine parameters as input to derive a steam flow to fuel flow ratio that minimizes or eliminates flame holding in a fuel nozzle of the gas turbine engine system.