A propulsion system includes a drive shaft movable about an axis of rotation, a fan, a fan shaft that drives the fan, and a reduction device coupling the drive shaft and the fan shaft. The reduction device has first and second reduction stages and includes a sun gear, centered on the axis and driven by the drive shaft, a ring gear that is coaxial with the sun gear and that drives the fan shaft about the axis, and planet gears distributed circumferentially about the axis between the sun gear and the ring gear. Each planet gear includes a first portion meshed with the sun gear and a second portion meshed with the ring gear. A diameter of the first portion is different from a diameter of the second portion, and the first portion of the planet gears extend between the second portion of the planet gears and the fan.

A turbomachine, a computing system for a turbomachine, and a method for overspeed protection are provided. The turbomachine includes a first rotor assembly interdigitated with a second rotor assembly together operably coupled to a gear assembly. A plurality of sensors is configured to receive rotor state data indicative of one or more of a speed, geometric dimension, or capacitance, or change thereof, or rate of change thereof, relative to the first rotor assembly or the second rotor assembly. A controller executes operations including receiving rotor state data from the plurality of sensors; comparing rotor state data to one or more rotor state limits; and contacting one or more of the first rotor assembly or the second rotor assembly to a contact surface adjacent to the respective first rotor assembly or the second rotor assembly if the rotor state data exceeds the rotor state limit.

An outer shroud of an intermediate casing for a dual flow turbine engine for an aircraft, the shroud including: an annular downstream portion provided with a shroud opening passing through an annular downstream edge of the shroud; a connecting member (50) attached to the annular downstream portion, and intended to attach an arm that passes through a secondary flow path; an air-sealing and fire-resistance device including: a portion including: a pad arranged in a hollow annular area of the annular downstream edge of the shroud; a blade protruding from the pad and clamped between a circumferential end and the radially outer end of the arm, a leaf spring (pressing the pad into the hollow annular area.

A turbine engine heat exchanger has: a manifold having a first face and a second face opposite the first face; a plurality of first plates along the first face, each first plate having an interior passageway; and a plurality of second plates along the second face, each second plate having an interior passageway. A first flowpath passing through the interior passageways of the first plates, the manifold, and the interior passageways of the second plates.

A propulsion system is provided including an unducted rotating fan defining a fan axis; and a turbomachine disposed downstream from the unducted rotating fan, wherein the turbomachine defines a working gas flowpath flowing therethrough; wherein the propulsion system defines a third stream flowpath and an inlet passage having an inlet that is offset from the fan axis, wherein the inlet passage is configured to provide an inlet airflow to the working gas flowpath, and wherein the third stream flowpath bypasses at least a portion of the turbomachine.

An aircraft engine has a high pressure spool including a high pressure turbine drivingly connected to a high pressure compressor. A low pressure spool including a low pressure compressor is fluidly connected to the high pressure compressor. A low pressure turbine is drivingly connected to the low pressure compressor to drive the low pressure compressor. A load is drivingly connected to the low pressure turbine, the load consisting of one of a propeller and a helicopter rotor. A method of creating classes of an aircraft engine from an engine platform is disclosed.

A variable geometry inlet system of an aircraft engine includes an inlet duct. The inlet duct includes at least first and second sections moveable between extended and retracted positions such that the inlet duct defines a variable axial length of an inlet passage for selective flight conditions. The inclusion of acoustic treatment may assist in controlling noise.

A fan drive gear system for a turbofan engine according to an exemplary embodiment of this disclosure, among other possible things includes a sun gear that is rotatable about an axis, a plurality of intermediate gears driven by the sun gear, and a baffle that is disposed between at least two of the plurality of intermediate gears for defining a lubricant flow path from an interface between the sun gear and at least one of the plurality of intermediate gears. The baffle includes a channel with at least one ramp portion directing lubricant.

A turbine engine heat exchanger has: a manifold having a first face and a second face opposite the first face; a plurality of first plates along the first face, each first plate having an interior passageway; and a plurality of second plates along the second face, each second plate having an interior passageway. A first flowpath passing through the interior passageways of the first plates, the manifold, and the interior passageways of the second plates.

A three-stream gas turbine engine with an embedded electric machine and methods of operating the same are disclosed. In one aspect, a three-stream engine includes an electric machine operatively coupled with a shaft of the engine. The three-stream engine also includes a core engine and a primary fan and a mid-fan positioned upstream of the core engine. The primary fan and the mid-fan are operatively coupled with the shaft. During operation, the three-stream engine defines a tip speed ratio being defined by a tip speed of a rotor of the electric machine to a tip speed of a mid-fan blade of the mid-fan. The tip speed ratio is defined as being equal to or greater than 0.2 and less than or equal to 1.0.