What happened
On 2 July 2015, a Robinson R22 helicopter, registration ZS-HXP, was engaged in a game capture operation on a private farm named Oufontein in the Victoria West area of the Northern Cape. The pilot and a net-gun operator had been successfully capturing springbok using a net-gun method. During the final capture attempt of the day, the pilot positioned the aircraft approximately 15 metres above a group of antelope to allow the operator to deploy the net.
As the operator discharged the net gun, a malfunction occurred. The helicopter began to spin uncontrollably following the impact of the net with the aircraft's tail rotor. In an attempt to manage the descent, the pilot reduced engine power to idle just before the aircraft struck the ground. The impact was severe enough that the main rotor blades severed the tail boom from the fuselage. While the pilot escaped without injury, the net-gun operator sustained critical head injuries when a rotor blade struck the cockpit area. The operator passed away in the hospital four days later.
The investigation
An investigation by the SACAA AIID established that the aircraft was being operated under Part 137 regulations for game capture. The investigation focused on the mechanics of the net-gun discharge and the subsequent flight path of the aircraft. Investigators examined the wreckage, noting that the tail rotor was found 20 metres from the main impact site. The inquiry also reviewed the pilot's credentials, confirming a valid commercial license and sufficient experience, as well as the airworthiness of the Robinson R22.
Findings
- The primary cause of the accident was that one of the four weights attached to the net became lodged inside the barrel of the net gun during discharge.
- This malfunction caused the net to swing backward and strike the tail rotor.
- The interference with the tail rotor resulted in a loss of directional control and a clockwise spin.
- Meteorological conditions at the time were clear with light winds and did not contribute to the accident.
- The impact sequence caused the main rotor blades to strike the cabin and sever the tail boom.