An aircraft propulsion assembly includes a first engine and a second engine that are adjacent and a nacelle in which the engines are installed. The nacelle includes a common air inlet lip for the first engine and the second engine, the air flow being divided between the first engine and the second engine by a median lip which extends, at least partly, set back from said common air inlet lip. The common are inlet lip includes, directly in line with the median lip, a bottom lobe and a top lobe extending forward of the nacelle. Such a configuration makes it possible to be able to provide a high aerodynamic form between the fairings of the engines, without the risk of generating overspeeds in the air flow.

A gearbox for a gas turbine engine with a rotatably mounted structural component that is formed with an at least approximately rotationally symmetrical duct into which, starting from its radially inner area, oil from an oil supply which is fixedly attached at the housing can be introduced. Starting from the oil supply, an introduction direction of the oil into the duct encloses an angle of 90 or an angle of between 60 and 90 with the axial extension direction of the duct. Additionally, in the circumferential direction of the duct, the introduction direction of the oil encloses an angle with the radial extension direction that is larger than or equal to 0 and smaller than 90.

A gearbox for a gas turbine engine with a rotatably mounted structural component that is formed with an at least approximately rotationally symmetrical duct into which, starting from its radially inner area, oil from an oil supply which is fixedly attached at the housing can be introduced. Starting from the oil supply, an introduction direction of the oil into the duct encloses an angle of 90 or an angle of between 60 and 90 with the axial extension direction of the duct. Additionally, in the circumferential direction of the duct, the introduction direction of the oil encloses an angle with the radial extension direction that is larger than or equal to 0 and smaller than 90.

A third stream duct producing a third air stream at reduced pressure that is exhausted through a separate nozzle that is concentric with the main or primary engine nozzle. The third stream exhaust air from the separate concentric nozzle is exhausted to a location at which pressure is ambient or sub-ambient. The location at which the third stream air is exhausted contributes to the thrust of the aircraft. The airstream from the third air duct is exhausted through an exhaust nozzle of the third duct that is positioned at the interface between the aft of the airframe and the leading edge of the engine outer flaps. This location is a low pressure region that has a recirculation zone. The exhaust of third stream air to this low pressure region substantially reduces or eliminates this recirculation zone and associated boat tail drag, thereby improving the efficiency of the engine.

A gas turbine engine includes a first spool associated with a primary combustor, a second spool associated with a secondary combustor, and a third spool, each spool including a compressor and a turbine mounted to a shaft. A transmission and accessory gearing are enclosed within an housing of an accessory gearbox. The transmission rotationally couples the third spool to the second spool and accessory gearing. A method of operating the gas turbine engine includes supplying a first fuel flow rate to the primary combustor and supplying a second fuel flow rate to the secondary combustor within an intermediate speed range of the gas turbine engine.

A Duplex Turbine Guide Vane (DTGV) assembly for a turbojet engine includes DTGVs arranged on a non-rotating guide vane ring configured to be positioned coaxially in apposition with a rotatable turbine wheel comprising turbine blades. Each of the DTGVs has an internal channel configured for receiving a gas and delivering the gas toward the turbine blades.

A Duplex Turbine Guide Vane (DTGV) assembly for a turbojet engine includes DTGVs arranged on a non-rotating guide vane ring configured to be positioned coaxially in apposition with a rotatable turbine wheel comprising turbine blades. Each of the DTGVs has an internal channel configured for receiving a gas and delivering the gas toward the turbine blades.

A propulsion unit including: a gas generator including a compressor, a combustion chamber, a turbine, at least two compressed-air propulsion modules, each propulsion module including: a fan, a compressed-air turbine configured to drive the rotation of the fan, a manifold allowing the respective turbines of the compressed-air propulsion modules to be supplied with compressed air, wherein the manifold is configured to collect and mix: at least a portion of the flow that has passed through the combustion chamber of the gas generator, typically as it leaves the turbine, and at least one bypass flow, the bypass flow being a flow of air which is not passed through the combustion chamber of the gas generator.

A turbine diagnostic machine learning system builds one or more turbine engine performance models using one or more parameter or parameter characteristics. A model of turbine engine performance includes ranked parameters or parameter characteristics, the ranking of which is calculated by a model builder based upon a function of AIC, AUC and p-value, resulting in a corresponding importance rank. These raw parameters and raw parameter characteristics are then sorted according to their importance rank, and selected by a selection component to form one or more completed models. The one or more models are operatively coupled to one or more other models to facilitate further machine learning capabilities by the system.

A powerplant is provided that includes a first gas turbine engine, a second gas turbine engine, a second engine bypass flowpath and a flow control system. The first gas turbine engine includes a first core flowpath fluidly coupled with a first inlet and a first exhaust. The first core flowpath extends sequentially through a first compressor section, a first combustor section and a first turbine section. The second gas turbine engine a second core flowpath fluidly coupled with a second inlet and a second exhaust. The second core flowpath extends sequentially through a second compressor section, a second combustor section and a second turbine section. The flow control system fluidly couples the first inlet and the first exhaust to the second core flowpath during a first mode. The flow control system fluidly couples the first inlet and the first exhaust to the second engine bypass flowpath during a second mode.