ATSB Preliminary Report issued today:
History of the flight
The Robinson Helicopter Company model 22 helicopter (R22) registered VH-UXF was engaged in aerial mustering operations with another R22 helicopter registered VH-AOP. The pilot of UXF had returned from a refuelling stop and recommenced operations in the mustering area. When no radio transmissions were heard from UXF for approximately 15 minutes, the pilot of AOP commenced a search for UXF. After a short search, the wreckage of UXF was located at the edge of a claypan. The helicopter had impacted the ground heavily in an upright attitude and both the occupants survived the impact with what appeared to be severe injuries. After making them comfortable, the pilot of AOP departed to seek medical assistance. He returned approximately 80 minutes later with a doctor. The doctor reported that in the intervening period both occupants of UXF had died of their injuries.
Wreckage findings
On-site examination of the helicopter revealed that it had impacted heavily with little forward speed. Both main rotor blades exhibited evidence of low speed rotation at the time of impact and also exhibited minor damage from striking small trees. The tail rotor exhibited evidence of high speed rotation at the time of impact and was destroyed by ground contact. The helicopter remained upright and the on-site examination revealed a failure in the clutch shaft, which on initial inspection appeared to be from impact damage. The helicopter was recovered to an engineering facility for a more detailed examination.
The examination at the engineering facility revealed what appeared to be a pre-impact failure of the clutch shaft. The shaft was taken to the ATSB laboratory in Canberra for further examination. The remainder of the examination of the recovered helicopter revealed that the engine was operating at high power when the helicopter impacted the ground. In addition, no pre-impact damage to other helicopter systems was found that would have contributed to the accident.
The examination of the airframe revealed that a significant amount of equipment, comprised of solid objects, was stored under the seats, which compromised the crashworthiness of the seats.
The investigation is continuing.
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