Abstract: A method of fabricating an airfoil includes providing an airfoil core tube that is made of a rigidized ceramic fabric, using the airfoil core tube as a mandrel by braiding a plurality of ceramic fiber tows around the airfoil core tube to form one or more braided layers, where the airfoil core tube and the one or more braided layers forming an airfoil preform, and densifying the airfoil preform with a ceramic matrix material to thereby form a ceramic matrix composite airfoil.

Abstract: An airfoil wall that includes a wishbone-shaped fiber layup structure that has first and second arms that merge into a single leg. The leg includes fiber tows from each of the arms and the tows are interwoven in the leg. Each of the arms includes a first section that is distal from the leg and a second section that is proximal to the leg. The first section defines a first thickness and a first fiber tow count. The second section defines a second thickness that is greater than the first thickness and a second fiber tow count that is greater than the first fiber tow count. The single leg defines a third thickness that is greater than the second thickness and a third fiber tow count that is greater than the second fiber tow count.

Abstract: An airfoil wall that includes a wishbone-shaped fiber layup structure that has first and second arms that merge into a single leg. The leg includes fiber tows from each of the arms and the tows are interwoven in the leg. Each of the arms includes a first section that is distal from the leg and a second section that is proximal to the leg. The first section defines a first thickness and a first fiber tow count. The second section defines a second thickness that is greater than the first thickness and a second fiber tow count that is greater than the first fiber tow count. The single leg defines a third thickness that is greater than the second thickness and a third fiber tow count that is greater than the second fiber tow count.

Abstract: A method of forming a ceramic matrix composite includes fabricating a space filling insert by assembling the space filling insert from a fibrous ceramic material, placing the space filling insert into a tooling fixture, the tooling fixture having an internal shape complementary to a shape of the insert, and infiltrating the space filling insert with a first ceramic material. The method further includes forming a preform by laying up a plurality of fibrous ceramic plies and inserting the infiltrated space filling insert into a void defined by the plurality of plies. The method further includes infiltrating the preform with a second ceramic material.

Abstract: A method of fabricating an airfoil includes providing an airfoil core tube that is made of a rigidized ceramic fabric, using the airfoil core tube as a mandrel by braiding a plurality of ceramic fiber tows around the airfoil core tube to form one or more braided layers, where the airfoil core tube and the one or more braided layers forming an airfoil preform, and densifying the airfoil preform with a ceramic matrix material to thereby form a ceramic matrix composite airfoil.

Abstract: A method of forming a ceramic matrix composite (CMC) vane comprises drawing a continuous fiber sheet over at least one contoured surface to form a single-folded sheet. The single-folded sheet comprises an airfoil portion, a first platform at a first end of the airfoil portion, and an integral transition region between the airfoil portion and the first platform. The method further comprises mounting the airfoil portion on a mandrel, attaching a second platform to a second, opposing end of the airfoil portion to form a vane preform, and densifying the vane preform.

Abstract: An airfoil includes an airfoil wall that has a wishbone-shaped fiber layup structure. The structure includes two arms that merge into a single leg. The single leg includes fiber tows from each of the arms that are interwoven. The single leg forms at least a portion of the trailing edge of the airfoil wall. Each of the arms includes a first section that is distal from the single leg and a second section that is proximal to the single leg. The first section defines a first thickness, the second section defines a second thickness that is greater than the first thickness, and the single leg defines a third thickness that is greater than the second thickness.

Abstract: A testing arrangement includes a test specimen that is formed of a fiber composite that has first, second, and third groups of fiber ply layers. Each fiber ply layer is curved so as to have an elbow. The elbows are joined back-to-back at a central region to form first, second, and third arms that extend outwardly from the central region. The elbows define a space in the central region, and there is a space-filler within the space. The test specimen is mounted in a testing fixture such that the first and second arms are in four-point bend loading and the third arm is oriented vertically. The testing fixture is actuatable to apply an actuated load. There is an applied load on the third arm. The applied load and the actuated load cause stress in the space-filler for evaluating mechanical behavior of the space-filler.

Abstract: A method for processing a CMC airfoil includes nesting an airfoil fiber preform in a cavity of a fixture that has first and second tool segments, closing the fixture by rotating a first tool segment about a hinge, the closing causing the tool segments to clamp on a tail portion of the fiber preform and thereby conform the tail portion to the fixture. While in the fixture, the fiber preform is then partially densified with an interface coating material to form a partially densified fiber preform. While still in the fixture, one or more cooling holes are drilled into the trailing edge of the partially densified fiber preform. After the drilling, the partially densified fiber preform is removed from the fixture and further densified with a ceramic matrix material to form a fully densified CMC airfoil.

Abstract: A method of forming a ceramic matrix composite (CMC) vane comprises drawing a continuous fiber sheet over at least one contoured surface to form a single-folded sheet. The single-folded sheet comprises an airfoil portion, a first platform at a first end of the airfoil portion, and an integral transition region between the airfoil portion and the first platform. The method further comprises mounting the airfoil portion on a mandrel, attaching a second platform to a second, opposing end of the airfoil portion to form a vane preform, and densifying the vane preform.

Abstract: A multiple static vane component includes a plurality of airfoils each formed of ceramic matrix composite materials. Each of the airfoils are attached to an inner platform and an outer platform both formed of ceramic matrix composite materials. There is a plurality of individual parts forming the plurality of airfoils, the inner platform or the outer platform, bonded to each other with a braze joint. A gas turbine engine and a method are also disclosed.

Abstract: A method for processing a CMC airfoil includes nesting an airfoil fiber preform in a cavity of a fixture that has first and second tool segments, closing the fixture by rotating a first tool segment about a hinge, the closing causing the tool segments to clamp on a tail portion of the fiber preform and thereby conform the tail portion to the fixture. While in the fixture, the fiber preform is then partially densified with an interface coating material to form a partially densified fiber preform. While still in the fixture, one or more cooling holes are drilled into the trailing edge of the partially densified fiber preform. After the drilling, the partially densified fiber preform is removed from the fixture and further densified with a ceramic matrix material to form a fully densified CMC airfoil.

Abstract: An airfoil includes an airfoil wall that has a wishbone-shaped fiber layup structure. The structure includes two arms that merge into a single leg. The single leg includes fiber tows from each of the arms that are interwoven. The single leg forms at least a portion of the trailing edge of the airfoil wall. Each of the arms includes a first section that is distal from the single leg and a second section that is proximal to the single leg. The first section defines a first thickness, the second section defines a second thickness that is greater than the first thickness, and the single leg defines a third thickness that is greater than the second thickness.

Abstract: A method for processing a CMC airfoil includes nesting an airfoil fiber preform in a cavity of a fixture that has first and second tool segments, closing the fixture by rotating a first tool segment about a hinge, the closing causing the tool segments to clamp on a tail portion of the fiber preform and thereby conform the tail portion to the fixture. While in the fixture, the fiber preform is then partially densified with an interface coating material to form a partially densified fiber preform. While still in the fixture, one or more cooling holes are drilled into the trailing edge of the partially densified fiber preform. After the drilling, the partially densified fiber preform is removed from the fixture and further densified with a ceramic matrix material to form a fully densified CMC airfoil.

Abstract: A gas turbine engine includes a ceramic matrix composite (CMC) vane arc segments that are arranged in a circumferential row. Each of the CMC vane arc segments includes an airfoil section that defines first and second side walls, leading and trailing ends, and first and second radial ends. At the first radial end, the airfoil section has a single-sided platform that and the second side wall has a bearing surface. The single-sided platform of each of the CMC vane arc segments in the circumferential row is situated to bear against the bearing surface of the next of the CMC vane arc segments in the circumferential row.

Abstract: An airfoil vane multiplet includes airfoil tubes that each have airfoil tube fiber plies. A plurality of the airfoil tube fiber plies extend along the airfoil tube and turn to project outwardly from the airfoil tube. Connector fiber plies include airfoil holes through which the airfoil tubes extend. The connector fiber plies are interleaved with the plurality of airfoil tube fiber plies such that the airfoil tubes are secured together.

Abstract: A vane multiplet includes a plurality of airfoils that each have a flared end, a common platform piece, a plurality of seal, and a plurality of retainers. The common platform has airfoil sockets that each define an airfoil opening that is circumscribed by a groove. The flared ends of the airfoils are seated in the airfoil sockets such that the grooves and the airfoils together form seal channels that have an open side. The seals are disposed in the seal channels. The retainers have airfoil-shaped profiles and are disposed in the airfoil sockets to bound the open sides of the seal channels and retain the seal in the seal channel.

Abstract: A gas turbine engine includes a turbine section that has a plurality of turbine vanes. Each of the turbine vanes includes inner and outer platforms and an airfoil section that extends there between. The airfoil section is hollow and rib-less and has a first end at the outer platform and a second end at the inner platform. The airfoil section is tangentially bowed from the first end to the second end with a radius of curvature that is from 17 centimeters to 130 centimeters.

Abstract: A gas turbine engine includes a turbine section that has a plurality of turbine vanes. Each of the turbine vanes includes inner and outer platforms and an airfoil section that extends there between. The airfoil section is hollow and rib-less and has a first end at the outer platform and a second end at the inner platform. The airfoil section is tangentially bowed from the first end to the second end with a radius of curvature that is from 17 centimeters to 130 centimeters.

Abstract: A turbine airfoil usable in a turbine engine and having at least one ambient air cooling system is disclosed. At least a portion of the cooling system may include one or more cooling channels configured to receive ambient air at about atmospheric pressure. The ambient air cooling system may have a tip static pressure to ambient pressure ratio of at least 0.5, and in at least one embodiment, may include a tip static pressure to ambient pressure ratio of between about 0.5 and about 3.0. The cooling system may also be configured such that an under root slot chamber in the root is large to minimize supply air velocity. One or more cooling channels of the ambient air cooling system may terminate at an outlet at the tip such that the outlet is aligned with inner surfaces forming the at least one cooling channel in the airfoil to facilitate high mass flow.