Robinson R22 Helicopter Crash During Zebra Capture Operation in South Africa (ZS-RMZ)

Accident Overview and Location On 10 September 2019, at approximately 1210Z, a Robinson Helicopter Company R22 Beta helicopter, registration ZS-RMZ, crashed during a game capture operation at The Hills Eco Estate, east of Pretoria, South Africa. The accident site was located at GPS coordinates 25°51’09.40” South, 028°21’01.60” East, at an elevation of 4,896 feet above mean sea level. The helicopter was operating under private (Part 91) rules with one person on board. The pilot was assisting a ground team in capturing 21 zebras, with the boma erected between the estate boundary fence and high-tension wires in a rocky, mountainous area with a downslope. The helicopter had been towed to the site on a trailer, and both doors were removed for the operation. The pilot had completed a pre-flight inspection before takeoff. The pilot successfully herded the first two groups of zebras, totaling 12 animals, into the boma. During the operation, the wind initially blew from the south and later shifted to south-westerly. The pilot noted that substantially more power was required to maintain main rotor RPM when turning downwind, prompting a strategy to complete each turn into the wind. During the third group of four zebras, which included a foal protected by its mother, two animals entered the boma while the other two turned away. The pilot descended to apply pressure, then initiated a climb and left turn to create space between the zebras and the boma gate. As the pilot continued with a right turn to position the helicopter into the wind and entered hover, the helicopter encountered a low main rotor RPM condition. The pilot was unable to recover due to being too low and too slow. The tail rotor blades struck several tree branches, causing the tail rotor assembly to separate from the tail boom. The helicopter yawed approximately 90 degrees to the left, impacted a tree, rolled over to the right, and came to rest in a nose-down attitude in dense bush terrain. The pilot sustained minor cuts and bruises, while the helicopter suffered substantial damage, though the cockpit/cabin area remained intact. The pilot was secured by a three-point safety harness. The accident occurred in fine weather conditions. The METAR for Wonderboom Aerodrome (FAWB) at 1200Z, 10 minutes before the accident, indicated a temperature of 31°C, wind from the west at 9 knots, and clear skies. The density altitude was calculated at 7,541 feet, indicating high-density altitude conditions. The pilot, a 32-year-old male, held a valid commercial helicopter pilot licence with 5,012.5 total flying hours, including 230.4 hours on the Robinson R22. He also held a valid cull/livestock rating and a Class 1 aviation medical certificate. The helicopter was operated within its maximum take-off weight of 622 kilograms (1,370 pounds). The weight and balance calculation included the basic empty weight, removal of both doors, pilot weight, baggage, and fuel. Nineteen bottles of engine oil, totaling 16.9 kilograms, were recovered from the baggage hold, along with dual controls weighing 1.2 kilograms. The helicopter had a valid Certificate of Airworthiness and Certificate of Release to Service, with the last annual inspection certified on 16 April 2019 at 5,844.6 airframe hours, with 3.7 additional hours flown since.