Abstract: A propeller assembly for an aircraft includes a main shaft rotatable about a propeller axis, a rotor hub mounted to the main shaft, and a plurality of blades coupled to the rotor hub. Each blade is rotatably coupled to the rotor hub for rotation about a blade rotation axis. A control system rotates each blade about the corresponding blade rotation axis and includes a ball screw coupled to the main shaft for rotation about the propeller axis and configured to translate along the propeller axis, an actuator beam mounted on the ball screw, and a ball nut coupled to the ball screw. When the ball nut rotates relative to the ball screw, the ball screw translates relative to the main shaft along the propeller axis. A differential transmission is configured to rotate the ball nut relative to the ball screw such that the ball screw is translated.

Abstract: A gearbox system includes a first drive gear rotatable about an axis of rotation and a second drive gear disposed coaxial with the first drive gear and rotatable about the axis of rotation. An input shaft provides a first torque and includes an input gear. Driving pinions are operably connected to the input gear and positioned between the first drive gear and the second drive gear compliantly along a direction parallel to the axis of rotation. Each driving pinion drives the first drive gear in a first direction about the axis of rotation and drives the second drive gear in a second direction opposite the first direction about the axis of rotation. Each driving pinion transfers an equal second torque to the first drive gear and the second drive gear.

Abstract: A lubrication system for a transmission assembly includes a primary reservoir, at least one primary jet, a primary circulating system fluidly coupling the primary reservoir and the at least one primary jet, a secondary reservoir, at least one secondary jet, and a secondary circulating system fluidly coupling the primary reservoir and the at least one secondary jet and fluidly coupling the primary reservoir and the secondary reservoir.

Abstract: A lubrication system for a transmission assembly includes a primary reservoir, at least one primary jet, a primary circulating system fluidly coupling the primary reservoir and the at least one primary jet, a secondary reservoir, at least one secondary jet, and a secondary circulating system fluidly coupling the primary reservoir and the at least one secondary jet and fluidly coupling the primary reservoir and the secondary reservoir.

Abstract: A gearbox for a rotary wing aircraft including a sump, a primary lubricant reservoir fluidically connected to the sump, one or more primary lubricant jets fluidically connected to the primary lubricant reservoir, an auxiliary lubricant reservoir fluidically connected to the sump, one or more auxiliary lubricant jets fluidically connected to the auxiliary lubricant reservoir, and at least one valve selectively fluidically connecting the sump and the primary lubricant reservoir based on a first lubricant pressure and the sump and the auxiliary lubricant reservoir based on a second lubricant pressure at the at least one valve.

Abstract: A gearbox system includes a first drive gear rotatable about an axis of rotation and a second drive gear disposed coaxial with the first drive gear and rotatable about the axis of rotation. An input shaft provides a first torque and includes an input gear. Driving pinions are operably connected to the input gear and positioned between the first drive gear and the second drive gear compliantly along a direction parallel to the axis of rotation. Each driving pinion drives the first drive gear in a first direction about the axis of rotation and drives the second drive gear in a second direction opposite the first direction about the axis of rotation. Each driving pinion transfers an equal second torque to the first drive gear and the second drive gear.

Abstract: A gearbox for a rotary wing aircraft including a sump, a primary lubricant reservoir fluidically connected to the sump, one or more primary lubricant jets fluidically connected to the primary lubricant reservoir, an auxiliary lubricant reservoir fluidically connected to the sump, one or more auxiliary lubricant jets fluidically connected to the auxiliary lubricant reservoir, and at least one valve selectively fluidically connecting the sump and the primary lubricant reservoir based on a first lubricant pressure and the sump and the auxiliary lubricant reservoir based on a second lubricant pressure at the at least one valve.

Abstract: A lubrication system includes an additive and a delivery system. During normal operational conditions, the lubricating oil circulating in the transmission system is collected and contained in a secondary oil reservoir to retain a quantity of the lubricating oil for use in an oil-out condition. When an oil-out condition is detected, the additive is injected and mixed with the collected lubricating oil in the secondary oil reservoir or dispersed directly into a power transmission gearbox housing to enhance the characteristics of the lubricating oil and increases the operational time period of the power transmission gearbox during an oil-out condition.

Abstract: A lubrication system includes an additive and a delivery system. During normal operational conditions, the lubricating oil circulating in the transmission system is collected and contained in a secondary oil reservoir to retain a quantity of the lubricating oil for use in an oil-out condition. When an oil-out condition is detected, the additive is injected and mixed with the collected lubricating oil in the secondary oil reservoir or dispersed directly into a power transmission gearbox housing to enhance the characteristics of the lubricating oil and increases the operational time period of the power transmission gearbox during an oil-out condition.

Abstract: A lubrication system includes an additive and a delivery system. During normal operational conditions, the lubricating oil circulating in the transmission system is collected and contained in a secondary oil reservoir to retain a quantity of the lubricating oil for use in an oil-out condition. When an oil-out condition is detected, the additive is injected and mixed with the collected lubricating oil in the secondary oil reservoir or dispersed directly into a power transmission gearbox housing to enhance the characteristics of the lubricating oil and increases the operational time period of the power transmission gearbox during an oil-out condition.

Abstract: A rotor hub fairing system includes an upper hub fairing, a lower hub fairing and a shaft fairing therebetween. The rotor hub fairing system is attached to the counter-rotating, coaxial rotor system through a bearing arrangement such that the shaft fairing may be positioned at an azimuthal position about the main rotor axis of rotation relative the airframe by a de-rotation system. The de-rotation system controls the position of the shaft fairing about the axis of rotation such that the shaft fairing is prevented from rotating freely in unison with either shaft as may otherwise result during some flight regimes.

Abstract: A de-rotation system includes a first ring gear defined about an axis of rotation, a second ring gear defined about the axis of rotation and a gear set in meshing engagement with the first ring gear and the second ring gear to control a position of a housing about the axis of rotation.

Abstract: A de-rotation system includes a first ring gear defined about an axis of rotation, a second ring gear defined about the axis of rotation and a gear set in meshing engagement with the first ring gear and the second ring gear to control a position of a housing about the axis of rotation.

Abstract: A differential speed transmission for varying the rotational speed of an input shaft relative to an output shaft wherein the differential speed transmission is characterized by: a pair of opposed first stage face gears each having a second stage pinion gear co-rotating therewith, a first stage input pinion disposed between and engaging each of the face gears to effect counter-rotation of the face gears and the second stage pinions, and a second stage face gear engaging each of the second stage pinions for driving the output shaft.

Abstract: A zero clearance locking mechanism for a disconnect coupling device for a segmented driveshaft wherein the disconnect coupling device includes an input disconnect member having an input splined coupler integrated in combination therewith, an output disconnect member having an output splined coupler integrated in combination therewith, and a coil spring disposed in combination with the input disconnect member and operative to provide a biasing force.