The Australian Transport Safety Bureau (ATSB) has released its report into the fatal crash of an helicopter near Julia Creek last year.
The two-seat Robinson R22 was mustering cattle from Dalgonally Station on May 9, 2011, when it crashed from a height of only 130 feet.
Subsequent examination found that the two v-belts that connect the engine drive to the rotor drive both separated, cutting off power to both rotors. The pilot didn't have time to establish an autorotation before the aircraft hit the ground.
From the ATSB report, it is clear that front belt partially dislodged from the drive sheave and consequently deteriorated rapidly, compromising the redundancy and leading to the failure of the rear belt.
The investigation report makes no safety recommendations, although the ATSB did release safety advisory notice AO-2011-060-SAN-001 encouraging operators and maintainers to inspect the R22 drive belts.
Click here to download the full ATSB accident investigation report.