Flow multiplier systems for aircraft are described herein. A flow multiplier system includes a turbo-compressor having a compressor, a turbine, and a drive shaft coupled between the compressor and the turbine. A compressor outlet of the compressor is fluidly coupled to an ejector in a gas turbine engine. The system also includes a supply line fluidly coupling a compressed air tank and a turbine inlet and a valve coupled to the supply line. The system includes a controller configured to, based on an input signal requesting to increase output power of the gas turbine engine, send a command signal to open the valve to enable a flow of pressurized air from the compressed air tank to the turbine inlet. The turbine drives the compressor to create high pressure air at the compressor outlet, which is provided into the gas turbine engine to increase the output power.

Bleed air systems for use with aircraft and related methods are disclosed. An example apparatus includes a compressor having a compressor inlet and a compressor outlet. The compressor inlet to receive airflow from a first air supply source. An air mixing device having a first mixer inlet to receive compressed air from the compressor outlet and a second mixer inlet to receive bleed air from a bleed air system. The bleed air to provide a motive fluid to enable the air mixing device to mix the bleed air and the compressed air to produce mixed air for the anti-icing system.

This invention concerns an aircraft propulsion system in which an engine has an engine core comprising a compressor, a combustor and a turbine driven by a flow of combustion products of the combustor. At least one propulsive fan generates a mass flow of air to propel the aircraft. An electrical energy store is provided on board the aircraft. At least one electric motor is arranged to drive the propulsive fan and the engine core compressor. A controller controls the at least one electric motor to mitigate the creation of a contrail caused by the engine combustion products by altering the ratio of the mass flow of air by the propulsive fan to the flow of combustion products of the combustor. The at least one electric motor is controlled so as to selectively drive both the propulsive fan and engine core compressor.

A method for determining an engine heath of an aircraft engine includes determining, by one or more control devices, the aircraft engine is operating in a bleed off condition; determining, by the one or more control devices, a first engine health modifier value while the aircraft engine is operating in the bleed off condition, the first of engine health modifier value including a compressor leakage flow value; determining, by the one or more control devices, a second plurality of engine health modifier values while the aircraft engine is operating in a bleed on condition; and determining, by the one or more control devices, an engine health parameter using at least one of the second plurality of engine health modifier values determined while the aircraft engine is operating in the bleed on condition and the compressor leakage flow value determined while the aircraft engine was operating in the bleed off condition.

A fuel cell system includes a control unit that is configured to perform highland control for increasing an amount of electric power generated per unit time by a fuel cell and increasing a rotational speed of a compressor such that an operating point of the compressor falls outside a surging region, in comparison with a case where a highland condition that an outside air pressure determined from an outside air pressure-associated information is lower than an outside air pressure threshold determined in advance is not fulfilled, when the highland condition is fulfilled in starting electric power generation by the fuel cell.

A system for identifying timeframes for borescope inspections for a gas turbine engine, having: monitoring systems monitor engine conditions, derive engine condition information and communicate such information to processors; feature interpreter module electronically communicates (i) with processors to process engine condition information, and (ii) feature interpreter information to processors, such information defines a probability of a FOD event; accumulator module electronically communicates (i) with processors to processes feature interpreter information, stored information since a last borescope inspection, and (ii) accumulator information to processors, such information defines an accumulated probability of a FOD event; and predictor and inspection planner module electronically communicates (i) with processors to processes accumulator information and stored information defines a threshold limits for a probability of a FOD event, and (ii) predictor and inspection planner information to processors, such information identifies a timeframe for a next borescope inspections predicted to occur before a FOD event.

An acquisition unit is configured to acquire measurement values of a target device. The measurement values that are acquired include at least a temperature and a flow rate of an input fluid to be input to the target device, and a temperature and a flow rate of an output fluid to be output from the target device. A correction unit is configured to obtain a correction measurement value by which the measurement values are corrected through thermal equilibrium calculations based on the measurement values. A distance calculation unit is configured to calculate a Mahalanobis distance with a factor of the correction measurement value.

A system is provided for cross engine coordination during gas turbine engine motoring. The system includes a first gas turbine engine of a first engine system, a first air turbine starter of the first engine system, a first starter air valve of the first engine system, and a controller. The controller is operable to command the first starter air valve to control delivery of compressed air to the first air turbine starter during motoring of the first gas turbine engine, monitor cross engine data of a second gas turbine engine of a second engine system to detect a present condition or a commanded action that modifies an aspect of the compressed air received at the first starter air valve, and command an adjustment to the first engine system to compensate for the modified aspect of the compressed air based on the cross engine data.

A pressure and temperature probe includes a probe head, a probe tip extending from the probe head and ending with a sensor face, a pressure channel extending into the probe tip through the sensor face, and a temperature channel extending into the probe tip through the sensor face. A pressure sensor is in fluid communication with a pressure channel and a temperature sensor in fluid communication with the temperature channel. The temperature channel extends parallel to the pressure channel, and the temperature channel is fluidly separate from the pressure channel. The sensor face can be configured to minimally intrude the flowpath of a working fluid, thereby minimizing disruption of the flowpath. The probe can be configured on a gas turbine engine.

A power generation system includes a processor and memory storing instructions that cause the processor to receive a first set of sensor data indicative of one or more ambient conditions with respect to the power generation system, determine whether one of the one or more ambient conditions is above a respective threshold, and send a signal to a valve to open when the one of the one or more ambient conditions is below the respective threshold, such that the valve is configured to fluidly couple a first fluid exiting a compressor to an inlet of the compressor.