South African AS350 B3 Helicopter Accident at Grand Central Aerodrome (ZS-RIU)

Flight Details and Accident Sequence On 7 January 2014, a Eurocopter AS350 B3 helicopter, registration ZS-RIU, departed from Kya Sands in Randburg, Gauteng, for Grand Central Aerodrome (FAGC). The flight was a training operation involving an instructor pilot, a pilot undergoing a proficiency check, and two passengers. The aircraft was operated by Chopper Worx (Pty) Ltd. During the approach to FAGC, the instructor initiated a simulated full authority digital engine control (FADEC) failure. The pilot flying completed the required procedures from the rotor flight manual. Upon initial touchdown, the main rotor speed was high. The pilot attempted to reduce the rotor speed by increasing the collective pitch lever, which caused the helicopter to become airborne again to approximately 30 feet above ground level. The instructor then restored the FADEC to normal while airborne. The pilot closed the throttle, resulting in a rapid decay of rotor speed and a hard descent to the ground. The helicopter touched down hard, turned through 90 degrees, and came to rest in an upright position adjacent to taxiway 35 at FAGC. The accident site was located at GPS coordinates 25°59’13.44” South, 028°08’25.97” East, at an elevation of 5,325 feet above mean sea level. ## Damage and Injuries The helicopter sustained substantial damage to the tail boom and skid gear, which broke off during the impact sequence. The aircraft came to rest 80 meters from the initial impact point. None of the four occupants—two pilots and two passengers—sustained injuries. The accident was considered survivable due to the landing skids absorbing most of the impact energy, and all occupants were properly restrained by safety harnesses. There was no evidence of pre- or post-impact fire. ## Aircraft and Personnel Information The AS350 B3, serial number 3399, was manufactured by Eurocopter in 2003. At the time of the accident, the airframe had 3,982.06 total hours, and the engine (Arriel 2B, serial number 22199) had 3,982.6 hours since new. The helicopter was within its maximum all-up weight limitation of 4,960 pounds, with a take-off weight of 4,442 pounds. Post-impact examination found the engine free from any pre-impact malfunction or mechanical anomaly. The instructor pilot, a 47-year-old South African male, held an Airline Pilot Licence with 7,159.6 total flying hours and 1,916.6 hours on type. The pilot undergoing the proficiency check, also a 47-year-old South African male, held an Airline Pilot Licence with 4,546.8 total flying hours and 44 hours on type. Both pilots had valid licences and type endorsements. ## Meteorological and Operational Conditions The accident occurred during daylight conditions at 1256Z. Weather information obtained from the pilot’s questionnaire indicated a wind direction of 120°, wind speed of 3 knots, visibility of 10 km, temperature of 22 °C, and cloud cover of 3–4 octants with a cloud base of 8,000 feet. The helicopter was equipped with standard communication and navigation equipment required by regulations, with no recorded defects prior to the flight. The operator held a valid air operating certificate and air operating licence, and the helicopter was duly authorized under the AOC. The maintenance organization that certified the helicopter held a valid approval certificate. The helicopter was not fitted with a cockpit voice recorder or flight data recorder, as neither was required by regulations for this type of helicopter.