Abstract: According to one embodiment, a clutch may be coupled between a rotor system and a power train of a rotorcraft. The clutch may be operable to disengage the rotor system from the power train during operation of the power train. A clutch control system in communication with the clutch and include a rotorcraft condition sensor operable to sense an operating condition of the rotorcraft and a control unit operable to prevent the clutch from disengaging the rotor system from the power train if the operating condition of the rotorcraft fails to satisfy a predetermined criterion.

Abstract: According to one embodiment, a clutch may be coupled between a rotor system and a power train of a rotorcraft. The clutch may be operable to disengage the rotor system from the power train during operation of the power train. A clutch control system in communication with the clutch and include a rotorcraft condition sensor operable to sense an operating condition of the rotorcraft and a control unit operable to prevent the clutch from disengaging the rotor system from the power train if the operating condition of the rotorcraft fails to satisfy a predetermined criterion.

Abstract: The present invention includes a method of lubricating a gearbox, including moving a lubricant from the gearbox into a gear shroud via a flow-metering orifice in the gear shroud; and distributing the lubricant within the gearbox by operation of a gear turning within the gear shroud.

Abstract: In one particular embodiment, a method for making a fiber-reinforced, composite article having an internal passageway includes providing a layup tool, fiber placing a base layup onto the layup tool, and generating a groove in the base layup. The method further includes placing a mandrel in the groove, fiber placing a top layup onto the base layup and the mandrel, curing the base layup and the top layup, and removing the mandrel from the base layup and the top layup. In another particular embodiment, the mandrel is replaced with a non-removable tube.

Abstract: In one particular embodiment, a method for making a fiber-reinforced, composite article having an internal passageway includes providing a layup tool, fiber placing a base layup onto the layup tool, and generating a groove in the base layup. The method further includes placing a mandrel in the groove, fiber placing a top layup onto the base layup and the mandrel, curing the base layup and the top layup, and removing the mandrel from the base layup and the top layup. In another particular embodiment, the mandrel is replaced with a non-removable tube.

Abstract: In one particular embodiment, a method for making a fiber-reinforced, composite article having an internal passageway includes providing a layup tool, fiber placing a base layup onto the layup tool, and generating a groove in the base layup. The method further includes placing a mandrel in the groove, fiber placing a top layup onto the base layup and the mandrel, curing the base layup and the top layup, and removing the mandrel from the base layup and the top layup. In another particular embodiment, the mandrel is replaced with a non-removable tube.

Abstract: According to one embodiment, a clutch may be coupled between a rotor system and a power train of a rotorcraft. The clutch may be operable to disengage the rotor system from the power train during operation of the power train. A clutch control system in communication with the clutch and include a rotorcraft condition sensor operable to sense an operating condition of the rotorcraft and a control unit operable to prevent the clutch from disengaging the rotor system from the power train if the operating condition of the rotorcraft fails to satisfy a predetermined criterion.

Abstract: A multi-ratio rotorcraft drive system and a method of changing gear ratios thereof are disclosed. According to one embodiment, the multi-ratio rotorcraft drive system comprises a rotor system comprising one or more rotors and one or more engines. Each engine of the one or more engines is coupled to the rotor system through a multi-ratio transmission. The multi-ratio transmission comprises an output shaft coupled to the rotor system, an input shaft coupled to a respective engine of the one or more engines, a high speed clutch integrated into a high speed gear train, and a low speed clutch integrated into a low speed gear train. The high speed clutch and the low speed clutch are freewheeling clutches without a friction plate and are capable of disconnecting the output shaft and the input shaft in an overrunning condition when the output shaft spins faster than the input shaft.

Abstract: A multi-ratio rotorcraft drive system and a method of changing gear ratios thereof are disclosed. According to one embodiment, the multi-ratio rotorcraft drive system comprises a rotor system comprising one or more rotors and one or more engines. Each engine of the one or more engines is coupled to the rotor system through a multi-ratio transmission. The multi-ratio transmission comprises an output shaft coupled to the rotor system, an input shaft coupled to a respective engine of the one or more engines, a high speed clutch integrated into a high speed gear train, and a low speed clutch integrated into a low speed gear train. The high speed clutch and the low speed clutch are freewheeling clutches without a friction plate and are capable of disconnecting the output shaft and the input shaft in an overrunning condition when the output shaft spins faster than the input shaft.

Abstract: A multi-ratio rotorcraft drive system and a method of changing gear ratios thereof are disclosed. According to one embodiment, the multi-ratio rotorcraft drive system comprises a rotor system comprising one or more rotors and one or more engines. Each engine of the one or more engines is coupled to the rotor system through a multi-ratio transmission. The multi-ratio transmission comprises an output shaft coupled to the rotor system, an input shaft coupled to a respective engine of the one or more engines, a high speed clutch integrated into a high speed gear train, and a low speed clutch integrated into a low speed gear train. The high speed clutch and the low speed clutch are freewheeling clutches without a friction plate and are capable of disconnecting the output shaft and the input shaft in an overrunning condition when the output shaft spins faster than the input shaft.

Abstract: In one particular embodiment, a method for making a fiber-reinforced, composite article having an internal passageway includes providing a layup tool, fiber placing a base layup onto the layup tool, and generating a groove in the base layup. The method further includes placing a mandrel in the groove, fiber placing a top layup onto the base layup and the mandrel, curing the base layup and the top layup, and removing the mandrel from the base layup and the top layup. In another particular embodiment, the mandrel is replaced with a non-removable tube.

Abstract: A transmission for a rotary-wing aircraft has a differential torque-splitting mechanism associated with an input shaft. The differential has a drive disk coaxial with the shaft and integral in rotation with the shaft, a first driven member coaxial with the shaft and generally adjacent the drive disk, and a second driven member coaxial with the shaft and generally adjacent the drive disk. At least one pin engages each of the drive disk, the first driven member, and the second driven member. The first driven member is configured to drive a first transfer gear, and the second driven member is configured to drive a second transfer gear for supplying torque to a bull gear associated with a rotor mast.

Abstract: A multi-ratio rotorcraft drive system and a method of changing gear ratios thereof are disclosed. According to one embodiment, the multi-ratio rotorcraft drive system comprises a rotor system comprising one or more rotors and one or more engines. Each engine of the one or more engines is coupled to the rotor system through a multi-ratio transmission. The multi-ratio transmission comprises an output shaft coupled to the rotor system, an input shaft coupled to a respective engine of the one or more engines, a high speed clutch integrated into a high speed gear train, and a low speed clutch integrated into a low speed gear train. The high speed clutch and the low speed clutch are freewheeling clutches without a friction plate and are capable of disconnecting the output shaft and the input shaft in an overrunning condition when the output shaft spins faster than the input shaft.

Abstract: A multi-ratio rotorcraft drive system and a method of changing gear ratios thereof are disclosed. According to one embodiment, the multi-ratio rotorcraft drive system comprises a rotor system comprising one or more rotors and one or more engines. Each engine of the one or more engines is coupled to the rotor system through a multi-ratio transmission. The multi-ratio transmission comprises an output shaft coupled to the rotor system, an input shaft coupled to a respective engine of the one or more engines, a high speed clutch integrated into a high speed gear train, and a low speed clutch integrated into a low speed gear train. The high speed clutch and the low speed clutch are freewheeling clutches without a friction plate and are capable of disconnecting the output shaft and the input shaft in an overrunning condition when the output shaft spins faster than the input shaft.

Abstract: A multi-ratio rotorcraft drive system and a method of changing gear ratios thereof are disclosed. According to one embodiment, the multi-ratio rotorcraft drive system comprises a rotor system comprising one or more rotors and one or more engines. Each engine of the one or more engines is coupled to the rotor system through a multi-ratio transmission. The multi-ratio transmission comprises an output shaft coupled to the rotor system, an input shaft coupled to a respective engine of the one or more engines, a high speed clutch integrated into a high speed gear train, and a low speed clutch integrated into a low speed gear train. The high speed clutch and the low speed clutch are freewheeling clutches without a friction plate and are capable of disconnecting the output shaft and the input shaft in an overrunning condition when the output shaft spins faster than the input shaft.

Abstract: A transmission for a rotary-wing aircraft has a differential torque-splitting mechanism associated with an input shaft. The differential has a drive disk coaxial with the shaft and integral in rotation with the shaft, a first driven member coaxial with the shaft and generally adjacent the drive disk, and a second driven member coaxial with the shaft and generally adjacent the drive disk. At least one pin engages each of the drive disk, the first driven member, and the second driven member. The first driven member is configured to drive a first transfer gear, and the second driven member is configured to drive a second transfer gear for supplying torque to a bull gear associated with a rotor mast.

Abstract: A transmission for a rotary-wing aircraft has a differential torque-splitting mechanism associated with an input shaft. The differential has a drive disk coaxial with the shaft and integral in rotation with the shaft, a first driven member coaxial with the shaft and generally adjacent the drive disk, and a second driven member coaxial with the shaft and generally adjacent the drive disk. At least one pin engages each of the drive disk, the first driven member, and the second driven member. The first driven member is configured to drive a first transfer gear, and the second driven member is configured to drive a second transfer gear for supplying torque to a bull gear associated with a rotor mast.

Abstract: A multi-ratio rotorcraft drive system and a method of changing gear ratios thereof are disclosed. According to one embodiment, the multi-ratio rotorcraft drive system comprises a rotor system comprising one or more rotors and one or more engines. Each engine of the one or more engines is coupled to the rotor system through a multi-ratio transmission. The multi-ratio transmission comprises an output shaft coupled to the rotor system, an input shaft coupled to a respective engine of the one or more engines, a high speed clutch integrated into a high speed gear train, and a low speed clutch integrated into a low speed gear train. The high speed clutch and the low speed clutch are freewheeling clutches without a friction plate and are capable of disconnecting the output shaft and the input shaft in an overrunning condition when the output shaft spins faster than the input shaft.

Abstract: A housing assembly for use in a rotorcraft includes a housing having an opening, a bearing configured to radially and/or axially support a shaft that is adapted to rotate, the bearing disposed within the opening of the housing, and a liner arranged between the housing and the bearing. The liner is made of a material selected from the group consisting of ceramic material, ceramic coated material, ceramic and metallic hybrid material, lightweight metallic material, lightweight metallic alloy material and lightweight metallic coated material.

Abstract: A multi-ratio rotorcraft drive system and a method of changing gear ratios thereof are disclosed. According to one embodiment, the multi-ratio rotorcraft drive system comprises a rotor system comprising one or more rotors and one or more engines. Each engine of the one or more engines is coupled to the rotor system through a multi-ratio transmission. The multi-ratio transmission comprises an output shaft coupled to the rotor system, an input shaft coupled to a respective engine of the one or more engines, a high speed clutch integrated into a high speed gear train, and a low speed clutch integrated into a low speed gear train. The high speed clutch and the low speed clutch are freewheeling clutches without a friction plate and are capable of disconnecting the output shaft and the input shaft in an overrunning condition when the output shaft spins faster than the input shaft.