Investigation of the Vibration Characteristics of the Eurocopter AS35OB Main Rotor Gearbox Under Different Operating Conditions

摘要

Different flight conditions can introduce complex changes to the vibration of helicopter transmissions, which may cause a vibration-based in- flight transmission diagnostic system to produce false alarms. An investigation into the vibration characteristics of the Eurocopter AS 350B main rotor gearbox under different operating conditions was conducted at AMRL. This investigation provided some in-depth understanding of the effects of different operating conditions, such as speed, torque and mast load, on the vibration of the gearbox. The analysis results showed that the effects of torque load were predominant and were dependent on operating speed and sensor locations, but that the effects of mast load were limited at most sensor locations. At the sensor location near the input shaft, the effects of torque and mast load on the vibration of the AS 350B gearbox were minimal.