Abstract: A gear box includes a housing, a shaft that is driven by the gear, the shaft including a recess, a bearing mounted between the shaft and the housing to support the shaft for rotation with respect to the housing about a rotation axis, and a ring assembly for axially securing the bearing to the shaft. The ring assembly surrounds the shaft and is seated in the recess. The recess has a retaining surface including a conical surface extending at an angle to the rotation axis, a curved surface, and a transition surface extending between the conical surface and the curved surface, the transition surface extending generally parallel to the rotation axis.

Abstract: A lubricant system includes a first gearbox defining a first internal cavity, a second gearbox defining a second internal cavity, a first lubricant cooler positioned external the first and second internal cavities, a second lubricant cooler positioned external the first and second internal cavities, and a plurality of fluid passages fluidly connecting the first lubricant cooler and second lubricant coolers to each of the first gearbox and the second gearbox. The first lubricant cooler and the second lubricant cooler are configured to hold lubricant. The fluid passages include a first main fluid passage fluidly connecting the first lubricant cooler to the first gearbox, a second main fluid passage fluidly connecting the second lubricant cooler to the second gearbox, a first auxiliary passage fluidly connecting the first lubricant cooler to the second gearbox, and a second auxiliary passage fluidly connecting the second lubricant cooler to the first gearbox.

Abstract: A lubricant system includes a first gearbox defining a first internal cavity, a second gearbox defining a second internal cavity, a first lubricant cooler positioned external the first and second internal cavities, a second lubricant cooler positioned external the first and second internal cavities, and a plurality of fluid passages fluidly connecting the first lubricant cooler and second lubricant coolers to each of the first gearbox and the second gearbox. The first lubricant cooler and the second lubricant cooler are configured to hold lubricant. The fluid passages include a first main fluid passage fluidly connecting the first lubricant cooler to the first gearbox, a second main fluid passage fluidly connecting the second lubricant cooler to the second gearbox, a first auxiliary passage fluidly connecting the first lubricant cooler to the second gearbox, and a second auxiliary passage fluidly connecting the second lubricant cooler to the first gearbox.

Abstract: A lubricant system includes a first gearbox defining a first internal cavity, a second gearbox defining a second internal cavity, a first lubricant cooler positioned external the first and second internal cavities, a second lubricant cooler positioned external the first and second internal cavities, and a plurality of fluid passages fluidly connecting the first lubricant cooler and second lubricant coolers to each of the first gearbox and the second gearbox. The first lubricant cooler and the second lubricant cooler are configured to hold lubricant. The fluid passages include a first main fluid passage fluidly connecting the first lubricant cooler to the first gearbox, a second main fluid passage fluidly connecting the second lubricant cooler to the second gearbox, a first auxiliary passage fluidly connecting the first lubricant cooler to the second gearbox, and a second auxiliary passage fluidly connecting the second lubricant cooler to the first gearbox.

Abstract: A gear box includes a housing, an actuator coupled to the housing, and a bearing assembly pivotably coupled to the actuator. The bearing assembly including an outer raceway, a cylindrical housing positioned within the outer raceway, and an annular bearing positioned between the outer raceway and the housing. The cylindrical housing has a first end and a second end opposite the first end. A sensor is coupled to the first end of the cylindrical housing and configured to monitor an operating condition of the annular bearing. A linkage couples the actuator to the second end of the cylindrical housing and an output shaft is rotatably coupled to the bearing assembly.

Abstract: A gear box includes a housing, an actuator coupled to the housing, and a bearing assembly pivotably coupled to the actuator. The bearing assembly including an outer raceway, a cylindrical housing positioned within the outer raceway, and an annular bearing positioned between the outer raceway and the housing. The cylindrical housing has a first end and a second end opposite the first end. A sensor is coupled to the first end of the cylindrical housing and configured to monitor an operating condition of the annular bearing. A linkage couples the actuator to the second end of the cylindrical housing and an output shaft is rotatably coupled to the bearing assembly.

Abstract: A gearbox includes a housing including a lubricant reservoir, at least one gear system arranged in the housing, at least one lubricant delivery passage operable to direct a flow of lubricant from a lubricant reservoir onto the at least one gear system, at least one lubricant return passage operable to guide the flow of lubricant to the lubricant reservoir, and a lubricant-out sensor fluidically connected to the at least one lubricant return passage. The lubricant-out sensor is operable to detect a non-pressure based parameter of the lubricant.

Abstract: An aircraft tail rotor system includes a rotating pitch change shaft, a translating element, and a pitch change bearing assembly including a first bearing and a second bearing. The pitch change bearing assembly is operable to transmit movement of the translating element to the rotating pitch change shaft via the first bearing or the second bearing. A failure section is formed at an interface between the first bearing and the translating element. When the failure section decouples the first bearing from the translating element such that the first bearing does not transmit movement of the translating element to the rotating pitch change shaft, the second bearing transmits movement of the translating element to the rotating pitch change shaft.

Abstract: A locking mechanism for a driveshaft disconnect coupling includes an input jaw member defining a rotation axis, an output jaw member connectable to the input jaw member for common rotation with the input jaw member, and a cartridge assembly. The cartridge assembly is fixed to the input jaw member, includes a pin, and defines a pin movement axis. The pin is movable along the pin axis between a radially inner position and a radially outer position, the pin being disengaged from the output jaw member in the radially inner position and the pin being engaged to the output jaw member in the radially outer position.

Abstract: An aircraft tail rotor system includes a rotating pitch change shaft, a translating element, and a pitch change bearing assembly including a first bearing and a second bearing. The pitch change bearing assembly is operable to transmit movement of the translating element to the rotating pitch change shaft via the first bearing or the second bearing. A failure section is formed at an interface between the first bearing and the translating element. When the failure section decouples the first bearing from the translating element such that the first bearing does not transmit movement of the translating element to the rotating pitch change shaft, the second bearing transmits movement of the translating element to the rotating pitch change shaft.

Abstract: A gearbox includes a housing including a lubricant reservoir, at least one gear system arranged in the housing, at least one lubricant delivery passage operable to direct a flow of lubricant from a lubricant reservoir onto the at least one gear system, at least one lubricant return passage operable to guide the flow of lubricant to the lubricant reservoir, and a lubricant-out sensor fluidically connected to the at least one lubricant return passage. The lubricant-out sensor is operable to detect a non-pressure based parameter of the lubricant.

Abstract: A locking mechanism for a driveshaft disconnect coupling includes an input jaw member defining a rotation axis, an output jaw member connectable to the input jaw member for common rotation with the input jaw member, and a cartridge assembly. The cartridge assembly is fixed to the input jaw member, includes a pin, and defines a pin movement axis. The pin is movable along the pin axis between a radially inner position and a radially outer position, the pin being disengaged from the output jaw member in the radially inner position and the pin being engaged to the output jaw member in the radially outer position.

Abstract: A coating and surface repair method is provided. The method includes positioning a high velocity air fuel (HVAF) gun proximate to a damaged hardened steel surface and forming a ceramic metallic coating on the damaged hardened steel surface by executing an HVAF thermal spray process using the HVAF gun.

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 method and system for magnetically detecting thermal degradation of a component. A multiple of ferrous metal segments are attached to a component not within a lubrication circuit of a lubrication system with a thermally-affected bonding agent. The thermally-affected bonding agent is operable to detach at a threshold temperature at least one of the multiple of ferrous metal segments such that the at least one of the multiple of detached ferrous metal segments enters the lubrication circuit of the lubrication system. The at least one of the multiple of ferrous metal segments which detached are then detected within the lubrication system.

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 mechanical system for high acceleration loading includes a mechanical element configured for rotational movement in a high acceleration environment. The mechanical element possesses a first density. A lubricant having a second density is disposed about the mechanical element. The first and second densities are substantially identical such that the mechanical element is substantially neutrally buoyant in the lubricant.

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 method for increasing oil-out survivability in a mechanical system having a plurality of components each having a least one surface, includes placing at least one of the plurality of components into a vacuum chamber having at least one broad-beam ion gun; supplying an inert gas to the broad-beam ion gun; accelerating the ionized inert gas to high kinetic energy; cleaning the surface of the component with the ionized and accelerated inert gas; supplying a hydrocarbon gas having at least 25 wt % acetylene to the broad-beam ion gun; ionizing the hydrocarbon gas; accelerating the ionized hydrocarbon gas to high kinetic energy; and directing the ionized and accelerated hydrocarbon gas to the surface of the component at a temperature of about 300° F. or less to deposit a carbon-based coating thereon.

Abstract: There is a coated, dynamic contact surface. The contact has a substrate and a carbon-based coating on the substrate. The coating has a coefficient of friction of about 0.5 or less and an atomic hydrogen content of about 5% to about 25%. There is also a mechanical system. There is a method for increasing oil-out survivability in a mechanical system.