What happened
On 10 May 2021, a Bell 47 helicopter, registered as ZS-HDC, departed from Krugers to perform proficiency training. The flight was being conducted under Part 91 regulations for the purpose of practicing simulated engine failure, specifically autorotation maneuvers.
The pilot initiated the autorotation procedure at an altitude of 6,300 feet above mean sea level, intending to conclude the maneuver by landing on Runway 35 at Krugersdorp Airfield. While the descent remained stable throughout the initial stages of the maneuver, the aircraft experienced a critical issue during the final approach. The pilot executed the flare maneuver at an inappropriate time, leading to a heavy impact upon touchdown. The force of the landing caused the tail rotor to make contact with the ground and resulted in the main rotor blades severing the tail boom. The aircraft remained upright, though the cabin structure collapsed onto the skids. There were no injuries to the pilot.
The investigation
The investigation, conducted by the SACAA AIID, reviewed the pilot's account of the flight and the physical state of the aircraft. The inquiry focused on the sequence of the autorotation maneuver, specifically the transition from the stable descent to the flare stage. The investigation examined the mechanical damage to the Bell 47, noting that the tail boom was severed and the aircraft sustained substantial damage.