Abstract: A propulsion system includes two gas turbine engines and an air-provisioning system. The air-provisioning system includes a first ejector, a second ejector, a plenum fluidically connected with the first ejector and the second ejector, and a first propulsor. The air-provisioning system is configured to bleed and mix air from each gas turbine engine in the ejectors so as to provide selectively a flow of plenum air from the plenum to the first propulsor at a desired pressure and a desired flow rate to power the first propulsor.

Abstract: A method of communication, within a processing system of a gas turbine engine, between a first electronic component and a second electronic component, comprising: generating by the first electronic component, a request, comprising a digital certificate, intern comprising a first host public key and a first client public key, signed with a first host private key, to initiate a trusted communication session with a second electronic component; encrypting at the first electronic component, at least a portion of the request with a first client private key; transmitting the request to the second electronic component; the first host private key and the first host public key defining a first asymmetric keypair and the first client private key and the first client public key defining a second asymmetric keypair.

Abstract: A hybrid propulsion system is provided. The system may comprise a gas turbine engine and a secondary engine, an inlet, an exhaust, a pressurized tank, and an expansion valve. The inlet may be in fluid communication with the ambient environment. The gas turbine engine may have a core passage including a compressor, a combustion chamber, and a turbine. The core passage may be in selective fluid communication with the inlet. The exhaust may be in fluid communication with the ambient environment and the core passage. The pressurized tank may be located upstream of the core passage. The pressurized tank may contain a cooling fluid. The expansion valve may be in fluid communication with the pressurized tank and the core passage. The pressurized tank may provide cooling fluid to the core passage to cool the gas turbine engine during operation of the secondary engine.

Abstract: Systems and methods of conditioning inlet air flow in a turbine engine. Where distortions in uniformity of inlet air flow are caused at least in part by the interaction of the air flow with the air inlet duct, a method of adaptively removing the distortions prior to the compressor stage comprises determining the distortion in the airflow; exposing the airflow to a plurality of correction vanes; and positioning the plurality of correction vanes based at least upon the determined distortion. An inlet conditioner system comprises an adaptable conditioning grid located within an air passage; a sensor suite configured to sense a characteristic of the airflow within the air passage; and a control system operably connected to the sensor suite and the adaptable conditioning grid. The control system may be adapted to configure the adaptable conditioning grid based on a sensed characteristic.

Abstract: A system may include a receiver configured to receive a communications signal from a transmitter and processing circuitry configured to: determine at least one frequency characteristic of the communications signal and compare the at least one frequency characteristic to at least one verified frequency characteristic stored by a memory associated with the processing circuitry to determine whether the transmitter is a verified transmitter. In some examples, the transmitter, receiver and communications signal are an optical transmitter, and optical receiver, and an optical signal, respectively.

Abstract: A hybrid propulsion system is provided. The system may comprise a gas turbine engine and a secondary engine, an inlet, an exhaust, a pressurized tank, and an expansion valve. The inlet may be in fluid communication with the ambient environment. The gas turbine engine may have a core passage including a compressor, a combustion chamber, and a turbine. The core passage may be in selective fluid communication with the inlet. The exhaust may be in fluid communication with the ambient environment and the core passage. The pressurized tank may be located upstream of the core passage. The pressurized tank may contain a cooling fluid. The expansion valve may be in fluid communication with the pressurized tank and the core passage. The pressurized tank may provide cooling fluid to the core passage to cool the gas turbine engine during operation of the secondary engine.

Abstract: A method for controlling an engine having a control module and smart nodes. The method includes maintaining a block chain ledger, which includes an information block from at least a preceding engine start, may be at the control module of the aircraft engine. The method also includes maintaining a hash of at least a digital certificate and data at one of the smart nodes; transmitting a message including the hash to the control module; receiving the message at the control module; determining a control hash based upon the information from at least a preceding engine start at the control module; module comparing the hash to the control hash at the control; and based upon the comparison, starting the engine and updating the block chain ledger as a function of the received message.

Abstract: A method of communication, within a processing system of a gas turbine engine, between a first electronic component and a second electronic component, comprising: generating by the first electronic component, a request, comprising a digital certificate, intern comprising a first host public key and a first client public key, signed with a first host private key, to initiate a trusted communication session with a second electronic component; encrypting at the first electronic component, at least a portion of the request with a first client private key; transmitting the request to the second electronic component; the first host private key and the first host public key defining a first asymmetric keypair and the first client private key and the first client public key defining a second asymmetric keypair.

Abstract: A cooling architecture can include a longitudinally extending radially inner shaft, a radially outer support, and a bearing assembly. The longitudinally extending radially inner shaft can include an inner race. The inner race can define an inner circumferential chamber configured to carry an inner working fluid. The radially outer support can include an outer race. The bearing assembly can include a plurality of roller bearings disposed radially between the inner race and the outer race. The bearing assembly can be configured to radially align the inner shaft with respect to the outer support.

Abstract: A system may include a receiver configured to receive a communications signal from a transmitter and processing circuitry configured to: determine at least one frequency characteristic of the communications signal and compare the at least one frequency characteristic to at least one verified frequency characteristic stored by a memory associated with the processing circuitry to determine whether the transmitter is a verified transmitter. In some examples, the transmitter, receiver and communications signal are an optical transmitter, and optical receiver, and an optical signal, respectively.

Abstract: A cooling architecture can include a longitudinally extending radially inner shaft, a radially outer support, and a bearing assembly. The longitudinally extending radially inner shaft can include an inner race. The inner race can define an inner circumferential chamber configured to carry an inner working fluid. The radially outer support can include an outer race. The bearing assembly can include a plurality of roller bearings disposed radially between the inner race and the outer race. The bearing assembly can be configured to radially align the inner shaft with respect to the outer support.

Abstract: A cooling architecture can include a longitudinally extending radially inner shaft, a radially outer support, and a bearing assembly. The longitudinally extending radially inner shaft can include an inner race. The inner race can define an inner circumferential chamber configured to carry an inner working fluid. The radially outer support can include an outer race. The bearing assembly can include a plurality of roller bearings disposed radially between the inner race and the outer race. The bearing assembly can be configured to radially align the inner shaft with respect to the outer support.

Abstract: A cooling architecture can include a longitudinally extending radially inner shaft, a radially outer support, and a bearing assembly. The longitudinally extending radially inner shaft can include an inner race. The inner race can define an inner circumferential chamber configured to carry an inner working fluid. The radially outer support can include an outer race. The bearing assembly can include a plurality of roller bearings disposed radially between the inner race and the outer race. The bearing assembly can be configured to radially align the inner shaft with respect to the outer support.

Abstract: A cooling architecture in a geared turbofan engine can include a longitudinally extending radially inner shaft, a radially outer support, and a bearing assembly. The longitudinally extending radially inner shaft can include an inner race. The inner race can define an inner circumferential chamber configured to carry an inner working fluid. The radially outer support can include an outer race. The bearing assembly can include a plurality of roller bearings disposed radially between the inner race and the outer race. The bearing assembly can be configured to radially align the inner shaft with respect to the outer support.

Abstract: An air-inlet duct includes a particle separator and an agglomerator. The particle separator is configured to receive atmospheric air laden with particles and to direct the particles into a scavenge passageway while allowing the atmospheric air to move into a compressor passageway thereby reducing the number of particles that enter the compressor passageway. The agglomerator is configured to cause the particles to be attracted to one another and cluster together.

Abstract: A gas turbine engine including a compressor, a turbine, and a variable-ratio unit is disclosed. The turbine is coupled to the compressor to drive rotation of multiple stages of the compressor. The variable-ratio unit is configured to transmit rotational power from the turbine to at least one stage of the compressor to drive rotation of the at least one stage of the compressor.

Abstract: Systems and methods of conditioning inlet air flow in a turbine engine. Where distortions in uniformity of inlet air flow are caused at least in part by the interaction of the air flow with the air inlet duct, a method of adaptively removing the distortions prior to the compressor stage comprises determining the distortion in the airflow; exposing the airflow to a plurality of correction vanes; and positioning the plurality of correction vanes based at least upon the determined distortion. An inlet conditioner system comprises an adaptable conditioning grid located within an air passage; a sensor suite configured to sense a characteristic of the airflow within the air passage; and a control system operably connected to the sensor suite and the adaptable conditioning grid. The control system may be adapted to configure the adaptable conditioning grid based on a sensed characteristic.

Abstract: A gas turbine engine including a compressor, a turbine, and a transmission is disclosed. The turbine is coupled to the compressor to drive rotation of multiple stages of the compressor. The transmission is configured to transmit rotational power from the turbine to at least one stage of the compressor to drive rotation of the at least one stage of the compressor.

Abstract: A gas turbine engine is disclosed which includes a bypass passage that in some embodiments are capable of being configured to act as a resonance space. The resonance space can be used to attenuate/accentuate/etc a noise produced elsewhere. The bypass passage can be configured in a number of ways to form the resonance space. For example, the space can have any variety of geometries, configurations, etc. In one non-limiting form the resonance space can attenuate a noise forward of the bypass duct. In another non-limiting form the resonance space can attenuate a noise aft of the bypass duct. Any number of variations is possible.

Abstract: An air-inlet duct includes a particle separator and an agglomerator. The particle separator is configured to receive atmospheric air laden with particles and to direct the particles into a scavenge passageway while allowing the atmospheric air to move into a compressor passageway thereby reducing the number of particles that enter the compressor passageway. The agglomerator is configured to cause the particles to be attracted to one another and cluster together.