A fan section includes a fan with fan blades. The fan section drives air along a bypass flow path in a bypass duct. A gear reduction is in driving engagement with the fan and has a gear reduction ratio of greater than 3.0 and less than 4.0. A low spool includes a low pressure turbine that drives a low pressure compressor and drives the gear reduction to drive the fan at a speed slower than the low pressure turbine. The low pressure compressor is a four-stage low pressure compressor. The low pressure turbine is a three-stage low pressure turbine. A high spool including a high pressure turbine that drives a high pressure compressor. The high pressure compressor is a nine-stage high pressure compressor. The high pressure turbine is a two-stage high pressure turbine. An exhaust gas exit temperature of greater than 900 degrees Fahrenheit and less than 1000 degrees Fahrenheit at maximum take-off.

A turbofan engine has a fan drivingly engaged by a shaft for rotation about a rotation axis and having: fan blades circumferentially distributed about the rotation axis and drivingly engaged by the shaft; an ice-accruing feature located on a surface of the fan exposed to an air flow flowing between the fan blades, the ice-accruing feature having a shape providing a non-axisymmetric ice accumulation on the fan to create a rotational imbalance; a balancing feature secured to the fan or to the shaft to counteract the ice-accruing feature such that the fan is rotationally balanced when the fan is free of ice, the balancing feature being located such as to be outside the air flow; an aircraft controller; and a sensor operatively connected to the fan and operable to send a signal to the aircraft controller, the signal indicative of the rotational imbalance caused by the ice-accruing feature.

A turbofan engine is provided. The turbofan engine includes a fan comprising a plurality of rotatable fan blades, each fan blade defining a fan tip speed; a turbomachine operably coupled to the fan for driving the fan, the turbomachine comprising a compressor section, a combustion section, and a turbine section in serial flow order and together defining a core air flowpath; and a gear box, wherein the turbomachine is operably coupled to the fan through the gear box, wherein a gear ratio of the gear box is greater than or equal to 1.2 and less than or equal to 3.0; wherein during operation of the turbofan engine at a rated speed the fan tip speed is greater than or equal to 1000 feet per second. In exemplary embodiments, during operation of the turbofan engine at the rated speed the fan pressure ratio is less than or equal to about 1.5.

A gas turbine engine includes a fan rotor driven by a fan drive turbine about an axis through a gear reduction to reduce a speed of the fan rotor relative to a speed of the fan drive turbine. A fan case surrounds the fan rotor, and a core engine with a compressor section, including a low pressure compressor. The fan rotor delivers air into a bypass duct defined between the fan case and the core engine. A rigid connection is between the fan case and the core engine includes three triangular-frame connecting members rigidly connected to the fan case at a fan case connection point, and to the core engine at a core engine connection point. The triangular-frame connecting members each are defined by two rigid legs which extend between the fan case and to the core engine, along directions each have a component extending radially inwardly and a component in opposed circumferential directions to each other. A plurality of non-structural fan exit guide vanes and the non-structural fan exit guide vanes are provided with an acoustic feature to reduce noise. The non-structural fan exit guide vanes are rigidly mounted to at least one of the fan case and the core engine.

An electric module of a fan includes a fan provided with blades which are rotatably movable inside a casing, and an electric machine having a rotor secured to the fan and a stator integrated into said casing. The rotor of the electric machine is integrated into the fan and includes a removable ring which captures axially and transversely from the radially outer ends the blades of the fan and which is received inside said stator which is integrated into the casing.

A gas turbine engine for an aircraft comprises an engine core comprising a turbine, a compressor, and a core shaft connecting the turbine to the compressor, wherein a compressor exit temperature is defined as an average temperature of airflow at the exit from the compressor; and a fan located upstream of the engine core, the fan comprising a plurality of fan blades extending from a hub, each fan blade having a leading edge and a trailing edge, wherein a fan rotor entry temperature is defined as an average temperature of airflow across the leading edge of each fan blade at cruise conditions and a fan tip rotor exit temperature is defined as an average temperature of airflow across a radially outer portion of each fan blade at the trailing edge at cruise conditions. A core to fan tip temperature rise ratio is in the range from 2.845 to 3.8.

The invention concerns a method for coating a core (1) for producing a turbomachine part (2) by isostatic compacting, for example a leading-edge shield of a blade, the coating method comprising the steps of:—S1: covering the core (1) by means of a first solution comprising a first refractory component configured to oppose the diffusion of species, the first component comprising a metal oxide,—S2: covering the core (1) by means of a second solution comprising a second component designed to bind the first component in such a way as to form a homogeneous layer, the second component comprising a mineral binder;—S3: applying a heat treatment to the covered core (1) in such a way as to dry the solution and solidify the coating.

A gas turbine engine for an aircraft that includes a nacelle, a fan, an engine core, a bypass duct extending between the engine core and the nacelle and guiding a bypass airflow through the bypass duct, and at least one non-structural strut extending in the radial direction within the bypass duct, wherein the non-structural strut includes an outside wall acting as a heat exchanger, and wherein the outside wall includes first transport means configured to transport in the outside wall at least one fluid to be cooled. It is provided that the non-structural strut further includes second transport means configured to transport a fluid to be heated, wherein the first transport means and the second transport means are configured such that the fluid to be heated is heated by the at least one fluid to be cooled and the at least one fluid to be cooled is cooled both by the bypass airflow and the fluid to be heated.

A propulsion system includes a drive shaft, a fan, a fan shaft, and a reduction device coupling the drive and fan shafts. The reduction device includes a first reduction stage and a second reduction state, and include a sun gear, centered on an axis of rotation of the drive and fan shafts and driven in rotation by the drive shaft, a ring gear, coaxial with the sun gear and that drives the fan shaft in rotation about the axis, and planet gears distributed circumferentially about the axis between the sun and ring gears, each planet gear including a first portion which is meshed with the sun gear and a second portion which is meshed with the ring gear, a diameter of the first portion being different from a diameter of the second portion, and an oil transfer bearing positioned between the fan and the reduction device.

Methods, apparatus, systems and articles of manufacture corresponding to a fan blade with intrinsic damping characteristics are disclosed. An example fan blade comprises an exterior body including a first side and a second side; a first hairpin structure in contact with (a) the first side of the exterior body and (b) the second side of the exterior body; and a second hairpin structure in contact with (a) the first side and (b) the second side, wherein the first hairpin structure and the second hairpin structure are made from different materials.