Abstract: A ram air turbine gearbox includes a turbine drive shaft defining a primary axis, a gear coupled to an outer surface of the drive shaft configured to transfer power from the drive shaft to a generator. A bearing is coupled to the outer surface of the drive shaft aft of the gear along the primary axis, a bearing support is positioned radially outside of the bearing configured for enclosing the bearing within a gearbox housing from an axially aft direction. A bearing liner is positioned radially between the bearing support and the bearing and a crest to crest wave spring positioned radially inside the bearing liner and axially forward of the bearing.

Abstract: A driveshaft for an aircraft ram air turbine, the driveshaft including a cylindrical body having an outer surface, an inner surface, a longitudinal axis, a first end section, a second end section opposite the first end section, and an elongated intermediate section connecting the first end section and the second end section. The outer surfaces of the elongated intermediate section includes at least three separate grooves initiating at a location proximate to the first end section and extending parallel to the longitudinal axis across the outer surface to a location proximate to the second end section, the grooves being separated equidistantly around a circumference of the outer surface. The grooves provide a high lateral bending stiffness and low torsional stiffness such that a drivetrain operates at a frequency below an operating range frequency and the driveshaft at a critical speed above an operating speed.

Abstract: A splined muff is provided for use with a ram air turbine (RAT). The splined muff includes a body formed of plastic material that acts as an insulator during a lightning strike. The body is formed to define an aperture and includes an interior facing spline for engagement with a complementary exterior facing spline; and an exterior facing spline for engagement with a complementary interior facing spline.

Abstract: A mounting frame for a ram air turbine includes a front support block having a top side opposite a bottom side. A rear support block is disposed opposite the front support block, the rear support block also having a top side, and a bottom side. A top plate extends between the front support block and the rear support block, the top plate having a forward end connected to the front support block proximate the top side of the front support block, an aft end connected to the rear support block proximate the top side of the rear support block. A bottom plate extends between the front support and the rear support opposite the top plate.

Abstract: A ram air turbine having: a strut assembly having an outer housing enclosing a first inner chamber; a generator housing operatively connected to the strut assembly, the generator housing having an outer surface enclosing a second inner chamber, the second inner chamber being fluidly connected to first inner chamber; a turbine assembly operably connected to the strut assembly, the turbine assembly in operation rotates in freestream air; and a power generation device mechanically connected to the turbine assembly and located within the second inner chamber, the power generation device generates power as turbine assembly rotates. The strut assembly includes a first screen portion having a plurality of inlet holes integrally formed in the outer housing. The generator housing includes a second screen portion having a plurality of outlet holes integrally formed in the outer surface. Freestream air passes through inlet holes, over the power generation device, and out outlet holes.

Abstract: Described herein is a system for increasing the robustness of a sealing surface and eliminating an expensive plating operation. The system includes an axially rotatable object comprising a first material that is subject to corrosion. The system also includes a radial shaft seal positioned radially outward from the axially rotatable object. The system also includes a sleeve coupled to the axially rotatable object, positioned between the axially rotatable object and the radial shaft seal and comprising a second material that is corrosion resistant.

Abstract: What is defined is a stow lock pin for use in preventing deployment of a ram air turbine of an aircraft, the aircraft having a first distance from the ram air turbine to an access window. The stow lock pin includes a tip configured to be received by a slot of the ram air turbine. The stow lock pin also includes a rod coupled to the tip and having an axial distance that is larger than the first distance.

Abstract: A ram air turbine (RAT) mounting system includes a frame with a forward end having a first side, a second side disposed opposite the first side, a third side, and a fourth side disposed opposite the third side. The frame also includes an aft end. A first mounting element is connected to the forward end of the frame proximate the first side and the third side. A second mounting element is connected to the forward end of the frame proximate the first side and the fourth side. A first rod is connected to the forward end of the frame proximate the second side and the third side. A second rod is connected to the aft end of the frame.

Abstract: A ram air turbine having: a strut assembly having an outer housing enclosing a first inner chamber; a generator housing operatively connected to the strut assembly, the generator housing having an outer surface enclosing a second inner chamber, the second inner chamber being fluidly connected to first inner chamber; a turbine assembly operably connected to the strut assembly, the turbine assembly in operation rotates in freestream air; and a power generation device mechanically connected to the turbine assembly and located within the second inner chamber, the power generation device generates power as turbine assembly rotates. The strut assembly includes a first screen portion having a plurality of inlet holes integrally formed in the outer housing. The generator housing includes a second screen portion having a plurality of outlet holes integrally formed in the outer surface. Freestream air passes through inlet holes, over the power generation device, and out outlet holes.

Abstract: An exemplary method of controlling fluid flow in a ram air turbine assembly, includes redirecting flow moving in an axial direction against the surface of a drive shaft to flow moving in a radial direction away from the drive shaft to limit flow of the fluid from a hydraulic pump to a generator.

Abstract: A ram air turbine system includes an actuator having a threaded portion, a rod having a threaded region at or near one end and an eyelet at an opposite end, and a bushing. The bushing has a first thread engaged with the threaded portion of the actuator, and a second thread engaged with the threaded region of the rod, such that an actuation force can be transmitted between the actuator and the rod through the bushing. The first and second threads of the bushing have different pitches.

Abstract: A driveshaft for an aircraft ram air turbine, the driveshaft including a cylindrical body having an outer surface, an inner surface, a longitudinal axis, a first end section, a second end section opposite the first end section, and an elongated intermediate section connecting the first end section and the second end section. The outer surfaces of the elongated intermediate section includes at least three separate grooves initiating at a location proximate to the first end section and extending parallel to the longitudinal axis across the outer surface to a location proximate to the second end section, the grooves being separated equidistantly around a circumference of the outer surface. The grooves provide a high lateral bending stiffness and low torsional stiffness such that a drivetrain operates at a frequency below an operating range frequency and the driveshaft at a critical speed above an operating speed.

Abstract: A splined muff is provided for use with a ram air turbine (RAT). The splined muff includes a body formed of plastic material that acts as an insulator during a lightning strike. The body is formed to define an aperture and includes an interior facing spline for engagement with a complementary exterior facing spline; and an exterior facing spline for engagement with a complementary interior facing spline.

Abstract: A ram air turbine (RAT) mounting system includes a frame with a forward end having a first side, a second side disposed opposite the first side, a third side, and a fourth side disposed opposite the third side. The frame also includes an aft end. A first mounting element is connected to the forward end of the frame proximate the first side and the third side. A second mounting element is connected to the forward end of the frame proximate the first side and the fourth side. A first rod is connected to the forward end of the frame proximate the second side and the third side. A second rod is connected to the aft end of the frame.

Abstract: A mounting frame for a ram air turbine includes a front support block having a top side opposite a bottom side. A rear support block is disposed opposite the front support block, the rear support block also having a top side, and a bottom side. A top plate extends between the front support block and the rear support block, the top plate having a forward end connected to the front support block proximate the top side of the front support block, an aft end connected to the rear support block proximate the top side of the rear support block. A bottom plate extends between the front support and the rear support opposite the top plate.

Abstract: An assembly includes an actuator assembly having a housing, a piston positioned at least partially within the housing and movable relative to the housing for an overall actuation stroke, a first spring operatively engaged between the piston and the housing to provide actuation biasing force therebetween, a second spring operatively engaged with the piston, and a spring guide. The spring guide is operatively engaged with the first spring and operatively engaged with the piston via a sliding connection. The spring guide is further configured to limit a stroke of the first spring such that the first spring contributes actuation biasing force between the piston and the housing for only a fractional portion of the overall actuation stroke of the piston.

Abstract: What is defined is a stow lock pin for use in preventing deployment of a ram air turbine of an aircraft, the aircraft having a first distance from the ram air turbine to an access window. The stow lock pin includes a tip configured to be received by a slot of the ram air turbine. The stow lock pin also includes a rod coupled to the tip and having an axial distance that is larger than the first distance.

Abstract: A ram air turbine with a turbine assembly and a power train, the turbine assembly only coupling to the entire power train upon reaching a desired rotational speed of the turbine assembly, the ram air turbine having a clutch mechanism, the engagement of which couples the turbine assembly to at least a portion of the power train, and a speed control mechanism that engages the clutch mechanism only when the turbine assembly attains at least the desired rotational speed.

Abstract: An exemplary method of controlling fluid flow in a ram air turbine assembly, includes redirecting flow moving in an axial direction against the surface of a drive shaft to flow moving in a radial direction away from the drive shaft to limit flow of the fluid from a hydraulic pump to a generator.

Abstract: An example ram air turbine drive shaft assembly includes a drive shaft that rotates about an axis to drive a hydraulic pump and a generator. The drive shaft has an interruption that redirects a fluid flowing from the hydraulic pump to the generator when the drive shaft is rotated.