The ATSB is warning Robinson R22 helicopter pilots of a drive belt risk following a fatal accident in north-west Queensland.
On May 9 a Robinson R22 Beta II (registered VH-DSD) helicopter crashed after its drive belts, which transmit engine power to the helicopter’s main and tail rotor blades, failed during mustering operations near Julia Creek. DSD and its pilot were conducting mustering operations in conjunction with another R22 helicopter when the pilot of DSD made a radio transmission indicating that a problem had occurred and that he was unable to continue flying.
The other pilot, and a third R22 pilot in the area, flew to the area and discovered the wreckage of DSD and that the pilot, the sole occupant had been fatally injured. Examination of the wreckage revealed that a drive belt had broken, and two belt fragments were found about 60 m from the main wreckage.
The ATSB preliminary investigation report, released yesterday, highlights a number of factors that can cause drive belt failure. These include excessive wear due to the misalignment of the belt drive sheaves, and operating the helicopter beyond the manufacturer’s recommended limits.
ATSB Chief Commissioner, Martin Dolan, said the accident is a grim reminder of the dangers facing pilots who conduct mustering-type flights.
“Pushing these helicopters to and beyond their normal limits can lead to excessive wear and potentially disastrous consequences,” Dolan said.
“The ATSB is urging Robinson R22 helicopter operators and maintainers to regularly and carefully check their R22 helicopter drive system for misalignment, abnormal wear or other indications of drive belt damage.”
Operators who find anything unusual with their R22 drive systems should immediately contact the ATSB by phoning 1800 020 616.
The investigation is continuing, with the ATSB planning to release a final investigation report within 12 months. For more information on this ongoing investigation click here.
CASA has also previously released an Airworthiness bulletin on the Robinson R22 main rotor drive system, which can be found here.
Robinson R22 VH-DSD suffered drive belt failure before the crash. (ATSB)
