Accident Details
On 3 October 2001, at approximately 1545Z, a Robinson R22 Beta helicopter, registration ZS-RFO, was conducting a ferry flight between two farms in the Groblersdal District, South Africa. The last point of departure was a farm, and the intended landing was at another farm in the same district. The accident site was located 30 km southwest of Groblersdal. Weather conditions were fine at the time.
While in straight and level flight, the pilot experienced a violent loss of control, characterized by a sudden steep turn to the left and random changes in attitude. The pilot identified a cyclic control failure and managed to use side-slip and rudder control to direct the helicopter toward a field, where he intentionally flew the helicopter into the ground. The front of the skids dug in and broke off after the aircraft skidded for approximately 10 meters. The sudden stoppage caused the main rotor to sever the tail boom.
Pilot and Aircraft Information
The pilot held a valid commercial pilot license and medical certificate with no restrictions. He had accumulated a total of 1,200 flying hours, with 137 hours on the Robinson R22 Beta type. The aircraft was a Robinson R22 Beta with registration ZS-RFO. According to available information, the helicopter was correctly maintained.
Investigation Findings
Investigation revealed that the helicopter's cyclic control system failed. Specifically, the end of the left-to-right cyclic control rod flared and pulled out, resulting in a loss of cyclic control. The inspection procedures during a manufacturer's periodic inspection (MPI) did not provide for detailed inspection of the cyclic and collective control rods. Additionally, the construction of some trailers used to transport helicopters was noted as suspect and requiring attention.
The pilot performed a controlled flight into terrain (CFIT), and both occupants escaped unharmed.
Probable Cause
The probable cause of the accident was a helicopter flight control system failure.