Abstract: A solution is provided comprising a strong base, a corrosion inhibitor, wherein the strong base is an alkali metal hydroxide, wherein the corrosion inhibitor is at least one of an organic acid having a-COOH functional group or an alkali metal salt one of an organic acid having a-COOH functional groups.

Abstract: A face skin for an acoustic panel may comprise a sheet defining a first surface and a second surface. A plurality of slots may be formed through the face skin using abrasive blasting. Each slot of the plurality of slots may comprise a first semi-circular wall and a second semi-circular wall opposite the first semi-circular wall.

Abstract: A method of making an airfoil includes making a refractory metal core that defines an interior of the airfoil by a tomo-lithographic process, making a mold that defines an exterior of the airfoil, inserting the refractory metal core into the mold, and pouring an airfoil material between the refractory metal core and the mold to cast the airfoil.

Abstract: A vane arm connection system for a gas turbine engine, includes a vane stem having a flatted head; a vane arm having a claw engaging the flatted head; and a load spreader having a spreader body defining structure engaging the flatted head, and at least one extension extending laterally from the spreader body.

Abstract: A remote temperature measurement system for a gas turbine engine includes an optical emitter/receiver in communication with the control system and a probe system embedded within a component of the gas turbine engine, the probe system within a line-of-sight of the optical emitter/receiver, the control system operable to determine a local temperature of the component in response to optical communication with the probe system.

Abstract: A compressor with negative coefficient of thermal expansion case material comprising a rotor having blades with tips, the case including an inner case comprising a negative coefficient of thermal expansion material, and a tip clearance located between the tips and the inner case; wherein the tip clearance is maintained responsive to a flow of air over the negative coefficient of thermal expansion material.

Abstract: A power extraction system for a gas turbine engine may comprise a low spool transmission and a low spool accessory gearbox. The low spool accessory gearbox may comprise a generator and a dual clutch transmission. The dual clutch transmission may be coupled between the low spool transmission and the generator.

Abstract: A damping apparatus includes a first sidewall defining a centerline axis, a second sidewall disposed coaxial with the first sidewall, a main cavity defined between the first sidewall and the second sidewall, and a damping material disposed in the main cavity.

Abstract: Methods and systems for a gas turbine engine comprising a modulated bleed valve are provided. The gas turbine engine may comprise a turbine nozzle coupled to a controller, a modulated bleed valve in communication with the controller, and a tangible, non-transitory memory providing instructions to the controller to perform operations. The operations may include receiving parameter values from the parameter sensor at various times, determining desired bleed airflows to flow through the modulated bleed valve at various times, and/or commanding the modulated bleed valve to assume an open configuration or a closed configuration at various times. The modulated bleed valve may be configured to allow bleed airflow to bypass a nozzle choke area of the turbine nozzle and join a nozzle airflow.

Abstract: A seal housing may comprise an aft flange, an outer diameter (OD) ring and a stopper. The stopper may extend radially inward from a radially inner surface of OD ring. The stopper may be configured to interface with a monobloc carbon seal. The stopper may comprise a circumferential stopping portion and an axial stopping portion. There may be a plurality of the stopper.

Abstract: A bearing compartment of a gas turbine engine includes a rotationally fixed structure defined about an engine longitudinal axis; a gutter section formed in the front support; an oil drainback assembly mountable to the gutter section to direct oil into a drain passage to communicate oil from the gutter.

Abstract: A stator assembly, in accordance with various embodiments, is disclosed herein. The stator assembly comprises either a first bumper or a first tab. The first bumper or the first tab extends circumferentially outward from a mating portion of the vane towards a slot in a ring. The ring may be an outer diameter (OD) ring or an inner diameter (ID) ring. The mating portion of the vane may be coupled to the ring by a potting component. The potting component may prevent direct contact between the vane and the ring.

Abstract: A scupper suitable for a bearing compartment of a gas turbine engine includes a windage blocker in a gutter section upstream of a drain hole, the windage blocker extends from a wall of the gutter section. A method for capturing wept oil in a bearing compartment of a gas turbine engine includes positioning a windage blocker adjacent to a drain hole forming a passage space and increasing a pressure upstream of the windage blocker to generate a vortex downstream of the windage blocker creating an oil re-circulation zone promoting oil drainage into the drain hole.

Abstract: A casting core assembly is disclosed herein. The casting core assembly comprises a casting core and a bumper assembly. The bumper assembly is disposed on an outer surface of the casting core. The bumper assembly comprises a receptacle and a metal apparatus. The metal apparatus may be a pin, a sphere, or the like.

Abstract: A machine has: an outer member; an inner member mounted for rotation about an axis relative to the outer member; and a seal system. The seal system has: a seal housing mounted to the outer member; one or more seal rings held by the seal housing and having an inner diameter surface; and a seal runner mounted to the inner member and having a first outer diameter surface portion contacting or facing the inner diameter surface of the one or more seal rings. The seal runner has a circumferential array of mounting features. One or more weights are mounted to one or more of the mounting features.

Abstract: A bearing assembly includes a bearing cage and a supplementary ring. The bearing cage includes an annular body and a plurality of bearing elements disposed about the annular body. The supplementary ring includes an annular collar and a plurality of retention elements. The annular collar is disposed concentrically about the bearing cage. The plurality of retention elements is connected to and extends axially from the first annular collar. Each retention element is aligned between adjacent bearing elements. The plurality of retention elements is disposed to retain the plurality of bearing elements in the annular body of the bearing cage.

Abstract: A process for manufacturing a composite rotor blade includes manufacturing an oversized root region of a root region of a composite rotor blade; fixturing the CMC blade into a machining fixture at a primary Y and Z axis datum located at an attachment fillet radii of the root region; machining V-notches into the oversized root region to form a Y? and Z? axis datum of a sacrificial datum system in relation to the primary Y and Z axis datum; applying an oversized coating layer over the attachment fillet radii of the root region; fixturing the CMC blade into a machining fixture at the Y? and Z? axis datum of the sacrificial datum system; machining the oversized coating layer to a machined coating layer forming a Y? and Z? axis datum with respect to the Y? and Z? axis datum of the sacrificial datum system; fixturing the CMC blade into a machining fixture at the Y? and Z? axis datum; and machining off the sacrificial datum system removing the V-notches.

Abstract: A vacuum arc remelt apparatus comprising a crucible having a wall, said wall having an interior and an exterior opposite said interior; an electrode within the crucible proximate the interior; an ingot within the crucible and below the electrode, wherein said ingot includes a crown and shelf; and a vibration source at the exterior of the crucible proximate the crown and shelf.

Abstract: A replaceable rotor blade tip clearance measurement device for a gas turbine engine, includes a threaded section along an axis and an integral abradable tip with an internal lattice geometry that extends from the threaded section along the axis.

Abstract: A turbine section includes a pair of adjacent turbine airfoils and an endwall extending between the airfoils. The endwall includes a first feature spanning approximately thirty percent pitch and having a first depression with a maximum depression located between twenty percent and eighty percent of the axial chord length of the first airfoil, a second feature spanning approximately thirty percent pitch and having a first peak with a maximum height located between sixty percent and ninety percent of the axial chord length of the first airfoil, and a third feature spanning approximately thirty percent pitch and having a second depression with a maximum depression located between twenty percent and fifty percent of the axial chord length of the second airfoil.