On 13 April 2005 at approximately 1130 Eastern Standard Time, the pilot of a Robinson Helicopter Company model R22 Beta, registered VH-HXU, was conducting cattle mustering operations near Mareeba, Qld, when he felt a significant airframe vibration and elected to conduct an immediate precautionary landing. Upon inspection with the engine still running, the pilot reported observing the clutch assembly shaking excessively, followed by the sudden fracture of the clutch shaft at the connection to the main rotor gearbox. The pilot was the only occupant of the helicopter and was not injured. There was no other damage to the helicopter.
