Abstract: A fan and compressor housing for an air cycle machine includes a fan inlet disposed around a center axis of the housing and having a fan inlet mounting flange, a compressor outlet having a compressor outlet mounting flange, and a compressor inlet having a compressor inlet mounting flange. The fan inlet mounting flange has a pinhole disposed thereon configured to receive a pin from a fan inlet diffuser housing and a fan inlet counterbore configured to receive a mating component from the fan inlet diffuser housing. The compressor outlet mounting flange has a compressor outlet counterbore configured to receive a first mating component from a condenser/reheater. The compressor inlet mounting flange has a compressor inlet counterbore configured to receive a second mating component from the condenser/reheater.

Abstract: An example terminal stud of a ram air fan connection assembly has a threaded portion extending from a head that is held within a slot of a base. The head has a sidewall that interfaces directly with the base. The sidewall has a length and a height. A ratio of the length to the height is from 2.18 to 2.35.

Abstract: A ram air fan assembly includes a motor/bearing housing that extends along a horizontal length of the ram air fan assembly. An inner housing assembly is in fluid communication with the motor/bearing housing to define a joint. The inner housing assembly includes first and second ellipse-shaped slots. The first slot is positioned at a first angle with respect to a radial axis of the inner housing assembly that is perpendicular to the horizontal length, and the second slot is positioned at a second angle with respect to the radial axis, the second angle being different from the first angle, and each slot extending along a first direction parallel to the horizontal length to define an axial width and extending along a radial axis to define a radial width being greater than the axial width.

Abstract: A turbine seal plate includes an inner rim with a labyrinth seal land that defines a central bore having a labyrinth seal diameter. The turbine seal plate also includes a housing coupling ring arranged radially outward of the inner rim. A housing pilot extends axially from the housing coupling ring and substantially parallel to the labyrinth seal land with respect to a radially inner portion of the housing pilot. The housing pilot has a housing pilot thickness, and a ratio of the housing pilot thickness to the labyrinth seal diameter is between 0.08 and 0.14. A frusto-conical body extends between the radially inner portion of the housing pilot and the inner rim of the turbine seal plate.

Abstract: A fan housing for an air cycle machine includes a fan exit flow passage and a ring disposed around a center axis of the fan housing and disposed around the fan exit flow passage. The ring includes a first end disposed axially opposite a second end and a guide surface facing radially inward relative the center axis and formed between the first end and the second end. The ring also includes a shelf disposed radially inward from the guide surface. The shelf includes a stop surface extending radially and disposed axially between the second end and the guide surface. The shelf also includes a shelf surface facing radially outward relative the center axis and extending axially between the first end and the stop surface.

Abstract: A fan shroud for an air cycle machine includes a tubular body extending axially between a first end and a second end of the shroud along a center axis of the fan shroud. A flange extends radially outward from the tubular body of the shroud at the first end of the shroud. At least one mounting hole extends through the flange. A sight hole extends through the flange and is positioned radially inward from the at least one mounting hole relative the center axis.

Abstract: A flow duct able to be connected to a ram outlet header includes a band having an annular shape and a glove connected to the band. The glove can include a first end that is annular in shape and connected to the band, a body that is curved and has a substantially U-shaped cross section with a first opening, and a second end that has a substantially U-shaped cross section and a second opening that is an extension of the first opening.

Abstract: A fan rotor blade extending radially from a hub is described. The fan rotor blade may include first surface and a second surface, where the first surface and second surfaces are respectively defined by a set of X-coordinates, Y-coordinates and Z-coordinates. The X, Y and Z coordinates can be set out in any of Tables T-1, T-2, E-1, and E-2. The X, Y, and Z-coordinates can also be scaled by a predetermined factor, with the X-coordinates are oriented in a tangential direction, the Z-coordinates are oriented in an axial direction, and the Y-coordinates are oriented in a radial direction.

Abstract: A turbine seal plate includes an inner rim with a labyrinth seal land that defines a central bore having a labyrinth seal diameter. The turbine seal plate also includes a housing coupling ring arranged radially outward of the inner rim. A housing pilot extends axially from the housing coupling ring and substantially parallel to the labyrinth seal land with respect to a radially inner portion of the housing pilot. The housing pilot has a housing pilot thickness, and a ratio of the housing pilot thickness to the labyrinth seal diameter is between 0.08 and 0.14. A frusto-conical body extends between the radially inner portion of the housing pilot and the inner rim of the turbine seal plate.

Abstract: A fan rotor for an aircraft environmental control system ram fan is provided. The fan rotor includes central body defining a central axis and a radius having a first radial distance that is defined as a distance from the central axis to an edge of the central body. A plurality of fan blades extend radially from the edge of the central body to a second radial distance, the second radial distance defined as a distance from the central axis to a tip of the fan blades. A shroud extends circumferentially between and connecting each of the plurality of fan blades. The shroud is located at a radial distance from the central axis that is greater than the first radial distance and includes one or more tuning features configured to mistune a vibration of the fan rotor during operation.

Abstract: A ram air fan housing includes an outer cylindrical housing portion centered on a central axis, with a first end and a second end positioned axially away from the first end. The ram air fan housing also includes an inner cylindrical housing portion centered on a central axis, with a first end and a second end positioned axially away from the first end. The first end of the outer cylindrical housing portion is connected to the first end of the inner cylindrical housing portion with a disk portion. The ram air fan housing also includes a first drain hole in the outer cylindrical housing portion adjacent to the second end of the outer cylindrical housing portion.

Abstract: A diffuser for a ram air fan assembly includes a perforated cone, an inlet ring seal, and an outlet ring seal. The perforated cone has a frustoconical shape symmetrical about an axis of the diffuser. The inlet ring seal is attached to, and axially disposed about, a first end of the perforated cone. The inlet ring seal includes a fan housing connection having a cylindrical shape. The outlet ring seal is attached to, and axially disposed about, a second end of the perforated cone. An average external diameter of the second end is greater than an average external diameter of the first end such that the perforated cone extends away from the inlet ring seal and radially outward from the axis of the diffuser.

Abstract: An air cycle machine has a housing which holds a compressor section, and a turbine section having an expansion area, and a fan section disposed outside of the housing. A shaft, which attaches to and is coaxial with the compressor section, the turbine section and the fan section, is supported by an air journal bearing and an air thrust bearing. The shaft has a hollow core for porting cooling air from the air journal bearing and the air thrust bearing, and a tube that extends into said expansion area and communicates cooling air from the turbine expansion area to the thrust bearing.

Abstract: A fan housing has a radially outer surface. A pair of radially intermediate surfaces includes a first surface spaced towards a first axial end, which has an inner bore positioned radially outward of an inner bore of a second surface. Vanes extend between the radially outer surface and an outer periphery of the pair of radially intermediate surfaces. A bearing bore extends radially inwardly of the first surface. A mounting lug nub is formed on an outer periphery of the radially outer surface. A first distance is defined between the first axial one end of the fan housing and an opposed axial end. A second distance is defined between the first axial end and a center of the mounting lug. A ratio of the first distance to the second distance is between 2.13 and 2.11. An intermediate part, a ram air fan and a method are also disclosed.

Abstract: A ram air fan outer housing for directing air from a ram air fan rotor and air from a ram air bypass into a ram air fan outlet. The outer housing includes an outer cylinder and a plenum connected at a joint region. The outer cylinder is made of a laminate stacking sequence of at least four adjacent layers of plain-weave carbon-fiber fabric in an A-B-B-A sequence. The plenum is made of a laminate stacking sequence of at least eight adjacent plenum layers of plain-weave carbon-fiber fabric in an A-B-B-A-A-B-B-A sequence. The plenum is joined to the outer cylinder at a joint region, the joint region includes a transition section transitioning the laminate stacking sequence from the eight adjacent layers of the plenum walls to the four adjacent layers of the outer cylinder walls.

Abstract: A ram air fan inner housing for a ram air fan assembly comprises a center body housing, an end cup attached to the center body housing, and a perforated cone. The perforated cone is attached to the center body housing and the end cup such that the perforated cone extends away from the center body housing and radially inward toward an axis of the inner housing.

Abstract: A compressor for pressurizing a flow of air within an aircraft including an inlet providing the flow of air to the compressor. An outlet provides the flow of air, after pressurization by the compressor, to a chamber of the aircraft. A diffuser assembly is disposed between the inlet and the outlet. The diffuser assembly includes one or more vanes at least partially impeding the flow of air through the diffuser assembly. A backing plate is included having a surface adjacent to the one or more vanes. The surface includes a relief feature that enables air to bypass the one or more vanes. The relief feature has an axial depth of about 0.5% to 2.5% of a width of a flow path through the diffuser assembly or of about 0.5% to 5% of a thickness of a flange of the backing plate. A method of operating a compressor is also included.

Abstract: An air cycle machine has a housing which holds a compressor section, and a turbine section having an expansion area, and a fan section disposed outside of the housing. A shaft, which attaches to and is coaxial with the compressor section, the turbine section and the fan section, is supported by an air journal bearing and an air thrust bearing. The shaft has a hollow core for porting cooling air from the air journal bearing and the air thrust bearing, and a tube that extends into said expansion area and communicates cooling air from the turbine expansion area to the thrust bearing.

Abstract: An air cycle machine has a housing which holds a compressor section, and a turbine section having an expansion area, and a fan section disposed outside of the housing. A shaft, which attaches to and is coaxial with the compressor section, the turbine section and the fan section, is supported by an air journal bearing and an air thrust bearing. The shaft has a hollow core for porting cooling air from the air journal bearing and the air thrust bearing, and a tube that extends into said expansion area and communicates cooling air from the turbine expansion area to the thrust bearing.

Abstract: A compressor for pressurizing a flow of air within an aircraft including an inlet providing the flow of air to the compressor. An outlet provides the flow of air, after pressurization by the compressor, to a chamber of the aircraft. A diffuser assembly is disposed between the inlet and the outlet. The diffuser assembly includes one or more vanes at least partially impeding the flow of air through the diffuser assembly. A backing plate is included having a surface adjacent to the one or more vanes. The surface includes a relief feature that enables air to bypass the one or more vanes. The relief feature has an axial depth of about 0.25% to 2.5% of a width of a flow path through the diffuser assembly or of about 0.5% to 5% of a thickness of a flange of the backing plate. A method of operating a compressor is also included.