An internal gear pump includes a pinion, a ring arranged around the pinion, and a cylindrical wall arranged around the ring. A support element, on which the pinion and the ring are supported, carries high-pressure liquid towards a recess located at the junction between the ring and the cylindrical wall, and also carries low-pressure liquid towards another recess located at another point of the junction between the ring and the cylindrical wall. The recess allows the load of the ring on the cylindrical wall to be reduced.

A flexible metal foil can be fixed on the inside part of a variable pitch vane control ring of a turbojet compressor, so as to close all through holes in which lever pins and their surrounding bushes are housed. As a result, the foil can retain the shank of the bush if the bush breaks. The use of such foil does not impose the development of a new model of control ring and its impact on the mass is small enough so that it does not affect engine performances. Therefore it avoids problems related to the breakage of bushes without having to make major changes to the existing system.

The present disclosure generally relates to methods for additive manufacturing (AM) that utilize integrated ribs to support thin walled annular structures. An annular wall fabricated using AM has a thickness less than 0.022 inches across a majority of a surface of the annular wall and a plurality of ribs having a thickness greater than 0.030 inches. The annular wall has a mean thickness less than 0.100 inches. The annular wall conforms to a surface of the component and a mean distance between the annular wall and the component is less than 0.080 inches.

A method of designing a turbofan engine according to an exemplary aspect of the present disclosure includes, among other things, providing a fan section including a plurality of fan blades, providing a low pressure turbine driving the plurality of fan blades through a gear train, providing a fan nacelle and a core nacelle, the fan nacelle at least partially surrounding the core nacelle, providing a fan bypass flow path defined between the core nacelle and the fan nacelle, and providing a fan variable area nozzle in communication with the fan bypass flow path and defining a fan nozzle exit area between the fan nacelle and the core nacelle.

The invention relates to a system for controlling variable pitch blades for a turbine engine, comprising an annular row of variable pitch blades extending about an axis (A) and each comprising a blade connected at the radially outer end thereof to a pivot (20) that defines a substantially radial axis of rotation of the blade and which is connected by a lever (34) to control means (40a, 40b) extending about said axis. The invention is characterized in that said control means include first links (40a) supported by said pivots and second links (40b) extending between said first links, said first and second links extending substantially along a same circumference of said axis and being connected to one another and to actuation means (56).

A strut assembly for a gas turbine engine includes an outer structural case. The outer structural case includes a first mounting pad for mounting a first strut and a second mounting pad for mounting a second strut. The outer structural case further includes a case ligament extending between the first mounting pad and the second mounting pad in a substantially straight direction to reduce an amount of bending stress on the outer structural case.

A tuned mass damper for reducing vibration on a component includes a shaft connector member configured to be coupled to the component and a cable termination member. The tuned mass damper also includes at least one cable coupled to the shaft connector member and to the cable termination member such that vibration of the component is transferred to the at least one cable via the shaft connector member and increased or decreased by the at least one cable.

According to an aspect, a system for a gas turbine engine includes a reduction gear train operable to drive rotation of a starter gear train that interfaces to an accessory gearbox of the gas turbine engine. The reduction gear train includes a starter interface gear that engages the starter gear train and a core-turning clutch operably connected to the starter interface gear. The reduction gear train also includes a geared rotary actuator including a primary planetary gear system, where the geared rotary actuator is operably connected to the core-turning clutch. The reduction gear train further includes a secondary planetary gear system operably connected to the primary planetary gear system and a core-turning input. The system also includes a mounting pad with an interface to couple a core-turning motor to the core-turning input of the reduction gear train.

One example aspect of the present disclosure is directed to a method for measuring engine performance. The method includes receiving first parameters related to engine performance prior to an engine wash event. The method includes receiving second parameters related to engine performance after the engine wash event. The method includes determining an engine performance prior to the engine wash event based on the first parameters. The method includes determining an engine performance after the engine wash event based on the second parameters. The method includes determining an effectiveness of the engine wash event based on the engine performance prior to the engine wash event and the engine performance after the engine wash event.

There is described a shaft shear event detection method. The method comprises obtaining a demodulated waveform of a shaft oscillation wave superimposed on a shaft rotational speed signal, comparing the amplitude to an amplitude threshold, detecting oscillation when the amplitude threshold is exceeded for a plurality of samples, and detecting a shaft shear when oscillation continues for a predetermined time limit.