A blade for use in a gas turbine engine, the blade comprising a blade portion and a fir tree root portion, the blade portion and the root portion having a connected passage for allowing cooling air to flow within the blade, the fir tree root portion having an air intake on its leading edge, the air intake allowing cooling air to enter the cooling passage and wherein the fir tree root portion comprises a plurality of projections, including at least a base projection and a top projection; and wherein the air inlet located in the base projection of the fir tree root portion and wherein the air inlet comprises at least 50% of the face of the base projection of the fir tree root portion.

An assembly for a turbomachine extending along an axis includes a combustion chamber having, at its downstream end, a downstream flange having a radially extending part. The assembly further includes a distributor disposed downstream of the combustion chamber and having a platform from which at least one vane extends radially. The platform includes an upstream flange extending radially and delimiting, with the radial part of the downstream flange disposed opposite it. An annular space for the circulation of cooling air opens into the combustion chamber at its radially internal end and has, at its radially external end, means of sealing attached to the distributor.

In accordance with at least one aspect of this disclosure, there is provided a method of accelerating a gas turbine engine. The method includes adding torque to a core of the gas turbine engine to accelerate rotation of the core by controlling fuel flow to a plurality of fuel injectors of the gas turbine engine. The method also includes adding torque to the core by powering an electric machine that is operatively connected to the core. In embodiments, controlling fuel flow to the plurality of fuel injectors is based on feedback from the electric machine.

In accordance with at least one aspect of this disclosure, there is provided a drive shaft system. In embodiments, the drive shaft system includes a generator shaft extending along a longitudinal axis with a longitudinal bore defined through the generator shaft. A thru shaft extends through the longitudinal bore of the generator shaft. In embodiments, the thru shaft includes, a front coupler mount at a first end operative to receive torque input, and a rear coupler mount at a second end opposite the first end.

A system and method for mitigating thermal loading between engine exhaust structures having different coefficients of thermal expansion. The engine exhaust structure comprises a metallic duct portion, a ceramic duct portion, and a double bipod fitting joining the metallic duct portion to the ceramic duct portion. The double bipod fitting is capable of flexing and taking up the thermal expansion differences between the joined metallic and ceramic ducts across the full temperature spectrum that an engine exhaust structure will experience in service.

A turbine blade for a gas turbine engine has an airfoil including leading and trailing edges joined by spaced-apart pressure and suction sides to provide an exterior airfoil surface extending from a platform in a spanwise direction to a tip. The external airfoil surface is formed in substantial conformance with multiple cross-sectional profiles of the airfoil described by a set of Cartesian coordinates set forth in Table 1, the Cartesian coordinates provided by an axial coordinate scaled by a local axial chord, a circumferential coordinate scaled by a local axial chord, and a span location.

A service tube assembly comprises a service tube having a threaded end portion and a ratchet hub spaced from the threaded end portion. The threaded end portion of the service tube is threadably engaged with a mating part. The assembly further comprises a locking member having a cantilever extending from a fixed end held relative to the mating part to a free end. A ratchet pawl is provided at the free end for engagement with the ratchet hub on the service tube.

The cooling system may comprise: an electric machine; a first conduit including a cable housing and an inlet; a plurality of conductive cables extending from the electric machine, the plurality of conductive cables disposed at least partially in the cable housing; and an electric fan disposed in the first conduit, the cooling system configured to passively flow air through the first conduit to cool the plurality of conductive cables during operation of the gas turbine engine, and the electric fan configured to actively cool the plurality of conductive cables after an engine shutdown of the gas turbine engine.

An oil collector for a mechanical reduction gear of a turbomachine, in particular for an aircraft, the reduction gear including a body having two opposite lateral faces configured to extend in part around planet gears of the reduction gear, the collector further including an internal oil circulation cavity connected firstly to oil inlets located on the faces, and on the other hand to at least one oil outlet, characterised in that at least one of the faces comprises includes columns and rows of several inlets each having a recess with a progressively increasing cross-section, each recess being delimited by walls, at least some of the walls having a hydrodynamic profile.

A nacelle for a gas turbine engine includes a leading edge at an upstream side of the nacelle. The nacelle further includes a trailing edge at a downstream side of the nacelle. The nacelle further includes an outer surface disposed between the leading edge and the trailing edge. The nacelle further includes a concave section continuous with the outer surface and disposed proximal to the trailing edge. The concave section includes an upstream end and a downstream end spaced apart from the upstream end. The concave section is curved radially inwards relative to the outer surface between the upstream end and the downstream end.