Abstract: A variable pitch fan for a propulsion device is provided. The variable pitch fan includes a plurality of fan blades coupled to a disk and a rotatable front hub covering the disk. Each fan blade is rotatable about a pitch axis to vary a pitch of the fan blade. The pitch is variable within a pitch range that is at least about 80° to about 130°. Each fan blade extends radially outward from the disk along a span from a root to a tip. A portion of the span adjacent the root defines a root span region, a portion of the span adjacent the tip defines a tip span region. A solidity of the variable pitch fan is at least 1.0 in the root span region.

Abstract: A gas turbine engine including a core having in serial flow order a compressor, a combustor, and a turbine—the compressor, combustor, and turbine together defining a core air flowpath. The gas turbine engine additionally includes a fan section mechanically coupled to the core, the fan section including a plurality of fan blades, and each of the plurality fan blades defining a pitch axis. An actuation device is operable with the plurality fan blades for rotating the plurality fan blades about their respective pitch axes, the actuation device including an actuator located outward of the core air flowpath to, e.g., simplify the gas turbine engine.

Abstract: A method and system for controlling a pitch of blades of a fan assembly having a centerline axis of rotation is provided. The system includes a pitch change mechanism (PCM) including a hydraulic actuator positioned axisymmetric with respect to the fan assembly and configured to angularly displace the blades of the fan assembly between a first position and a second position. The PCM further includes a plurality of hydraulic fluid supply lines coupled in flow communication between the hydraulic actuator and a hydraulic fluid transfer sleeve, the hydraulic fluid transfer sleeve configured to transfer a flow of pressurized hydraulic fluid across a gap between a stationary member of the hydraulic fluid transfer sleeve and a rotatable member of the hydraulic fluid transfer sleeve.

Abstract: An actuation assembly for a variable pitch fan for a gas turbine engine is provided. The actuation assembly generally includes a plurality of fan blades, a scheduling ring, and a plurality of linkage arms. The plurality of fan blades are rotatably coupled to a disk and extend radially therefrom. The scheduling ring is rotatable relative to the disk and has a plurality of slots. Each of the plurality of linkage arms are operatively coupled to one of the plurality of fan blades and to one of the plurality of slots. Each of the plurality of fan blades rotate according to a blade pitch schedule defined by the slot to which it is operatively coupled, and at least two of the plurality of slots define different blade pitch schedules.

Abstract: In one aspect the present subject matter is directed to a system for supporting shafts of an indirect-drive turbofan engine. The system includes a fan frame assembly that is coaxially aligned with a centerline of the turbofan engine and positioned forward of a reduction gear that couples a low pressure rotor shaft to a fan shaft. A compressor frame assembly is aligned with the centerline aft of the reduction gear and is positioned axially between a low pressure compressor and a high pressure compressor of the turbofan engine. A turbine frame assembly is coaxially aligned with the centerline and is positioned axially between a high pressure turbine and a low pressure turbine of the turbofan engine. The turbine frame assembly rotatably supports an aft end portion of a high pressure rotor shaft and an aft end portion of the low pressure rotor shaft.

Abstract: A gas turbine engine including a core engine and a fan configured in mechanical communication with the core engine is provided. The gas turbine engine also includes a plurality of outlet guide vanes positioned downstream from the fan along an axial direction defined by the gas turbine engine. The plurality of outlet guide vanes extend outwardly from an outer casing the core engine generally along the radial direction defined by the gas turbine engine. Each outlet guide vane defines a center of pressure and a pitch axis. The pitch axis of each outlet guide vane is positioned forward the center of pressure of each outlet guide vane such that in the event of a mechanical failure, the outlet guide vane defaults to a neutral position.

Abstract: A method of manufacturing a frangible laminate is provided. The method comprises constructing a reinforced polymer matrix, cutting the reinforced polymer matrix into a plurality of laminae, forming a laminate via stacking the plurality of laminae and at least one energy dissipating member, and consolidating the laminate.

Abstract: A frangible airfoil that mitigates adverse conditions associated with release of material resulting from impact damage to the composite blade is provided, the airfoil having provisions for dissipating energy, self-shredding, and predetermined release trajectory.

Abstract: A gas turbine engine having a forward thrust mode and a reverse thrust mode is provided. The gas turbine engine includes a variable pitch fan configured for generating forward thrust in the forward thrust mode of the engine and reverse thrust in the reverse thrust mode of the engine. The engine also includes a fan cowl surrounding the variable pitch fan, wherein the fan cowl forms a bypass duct for airflow generated by the fan. The fan cowl includes an aft edge that defines a physical flow area of the bypass duct, and a deflection device configured for deflecting airflow near the aft edge, wherein the deflection device is configured for operation in the reverse thrust mode of the engine. The physical flow area of the bypass duct at the aft edge remains the same in the forward thrust mode of the engine and in the reverse thrust mode of the engine.

Abstract: A method and system for a turbofan gas turbine engine system is provided. The gas turbine engine system includes a variable pitch fan (VPF) assembly coupled to a first rotatable shaft and a low pressure compressor LPC coupled to a second rotatable shaft. The LPC including a plurality of variable pitch stator vanes interdigitated with rows of blades of a rotor of the LPC. The gas turbine engine system also includes a speed reduction device coupled to said first rotatable shaft and said second rotatable shaft. The gas turbine engine system further includes a modulating pressure relief valve positioned between an outlet of said LPC and a bypass duct and a controller configured to schedule a position of said plurality of variable pitch stator vanes and said modulating pressure relief valve in response to an operational state of said turbofan gas turbine engine system and a temperature associated with said LPC.

Abstract: A rotary machine with at least one frangible composite blade that mitigates adverse conditions associated with release of material resulting from impact damage to the composite blade is provided. The composite blade having provisions for dissipating energy, self-shredding, and predetermined release trajectory. A method for manufacturing the composite blade and assembling the blade into a rotary machine is also provided.

Abstract: A unshrouded vane assembly for an unducted propulsion system includes a plurality of vanes which have non-uniform characteristics configured to generate a desired vane exit swirl angle.

Abstract: An unducted thrust producing system has a rotating element with an axis of rotation and a stationary element. The rotating element includes a plurality of blades, and the stationary element has a plurality of vanes configured to impart a change in tangential velocity of the working fluid opposite to that imparted by the rotating element acted upon by the rotating element. The system includes an inlet forward of the rotating element and the stationary element.

Abstract: Spaced apart counter-rotatable forward and aft rows of forward and aft propellers are mounted on forward and aft rotatable frames. Hydraulic rotary forward and aft pitch change actuators on the frames are operable for controlling pitch of the propellers. A hydraulic fluid supply outboard of the frames is connected to forward and aft rotary unions which are operable for transferring hydraulic fluid between forward and aft union stators to forward and aft union rotors mounted within the forward and aft rotary unions. The forward union rotor is operable to transfer the hydraulic fluid from the forward rotary union to the aft pitch change actuators and the aft union rotor is operable to transfer the hydraulic fluid from the aft rotary unions to the forward pitch change actuators. The forward and aft rotatable frames counter-rotatably mounted on a structural frame located forward or aft of the propellers.

Abstract: Axially spaced apart counter-rotatable forward and aft rows of forward and aft propellers mounted on forward and aft rotatable frames includes a flowpath passing through the forward and aft rotatable frames. Hydraulic rotary forward and aft pitch change actuators mounted on the aft rotatable frames are connected to and operable for controlling and setting pitch of the aft propellers. The pitch change actuators are mounted radially inwardly of the flowpath in a one to one ratio with forward and aft rotatable struts extending radially across the flowpath. One or more rotatable shafts extend through one or more of the rotatable struts and connect one or more of the pitch change actuators to one or more of the propellers. The pitch change actuators may be ganged together by unison rings having ring teeth engaging gear teeth on gears connected to the pitch change actuators or connected to the rotatable shafts.

Abstract: Axially spaced apart counter-rotatable forward and aft rows of forward and aft propellers mounted on forward and aft rotatable frames includes a flowpath passing through the forward and aft rotatable frames. Hydraulic rotary forward and aft pitch change actuators mounted on the aft rotatable frames are connected to and operable for controlling and setting pitch of the aft propellers. The pitch change actuators are mounted radially inwardly of the flowpath in a one to one ratio with forward and aft rotatable struts extending radially across the flowpath. One or more rotatable shafts extend through one or more of the rotatable struts and connect one or more of the pitch change actuators to one or more of the propellers. The pitch change actuators may be ganged together by unison rings having ring teeth engaging gear teeth on gears connected to the pitch change actuators or connected to the rotatable shafts.

Abstract: Spaced apart counter-rotatable forward and aft rows of forward and aft propellers are mounted on forward and aft rotatable frames. Hydraulic rotary forward and aft pitch change actuators on the frames are operable for controlling pitch of the propellers. A hydraulic fluid supply outboard of the frames is connected to forward and aft rotary unions which are operable for transferring hydraulic fluid between forward and aft union stators to forward and aft union rotors mounted within the forward and aft rotary unions. The forward union rotor is operable to transfer the hydraulic fluid from the forward rotary union to the aft pitch change actuators and the aft union rotor is operable to transfer the hydraulic fluid from the aft rotary unions to the forward pitch change actuators. The forward and aft rotatable frames counter-rotatably mounted on a structural frame located forward or aft of the propellers.

Abstract: A gas turbine engine rotor blade includes an airfoil, platform, shank, and dovetail integrally joined together. A dust escape hole extends through the platform adjacent a fillet bridging the platform and shank to bleed dust therefrom during operation.

Abstract: A turbine nozzle includes a hollow vane having opposite pressure and suction sides extending in span between outer and inner bands. The vane includes a forward flow channel behind the leading edge, an aft flow channel in front of the trailing edge, and a middle flow channel disposed therebetween. The three flow channels are disposed in flow communication with an outer plenum outside the outer band for receiving cooling air therefrom. The forward and middle channels are also disposed in flow communication with an inner plenum below the inner band for discharging the air. The aft channel discharges air through the inner band outside the inner plenum in split flow at different pressures.