Robinson R44 Raven I Accident at Lohatla Military Base (ZS-RNI)

Incident Overview and Flight Details On the morning of 16 March 2025, a Robinson R44 Raven I helicopter, registration ZS-RNI, was conducting a private flight under Part 91 of the Civil Aviation Regulations. The aircraft departed from Mons Farm in the Northern Cape Province, with the intended destination being Kabeljauws Farm in the Eastern Cape Province. The flight was operated by a 37-year-old male pilot holding a Private Pilot Licence, accompanied by one passenger. Visual meteorological conditions prevailed, with winds from 036° at 8 knots and visibility of 9,999 meters. The helicopter was refuelled to full capacity with 190 litres of Avgas 100LL prior to departure, and a pre-flight inspection identified no anomalies. ## Accident Sequence Approximately one hour into the flight, while near the Lohatla Military Base, the passenger requested a landing due to a medical condition. The pilot landed the helicopter in a grass-covered field within the base's border. After the passenger disembarked and returned to the aircraft approximately 10 minutes later, the helicopter took off. At an altitude of approximately 150 feet above ground level and a forward speed of 30 knots, the main rotor RPM decreased to below 97 percent, triggering the low main rotor RPM warning light. The RPM continued to decay to about 80 percent, and the pilot was unable to recover the helicopter. ## Emergency Response and Damage The pilot engaged autorotation but was unable to arrest the rate of descent to a safe vertical speed, resulting in a hard landing on the skid landing gears. The main rotor blades severed the tail boom during the accident sequence, causing substantial damage to the aircraft. No fatalities or injuries were reported. The pilot vacated the wreckage and reported the accident to the South African Police Service (SAPS), who responded swiftly to the scene. ## Post-Accident Examination Engineers from the aircraft maintenance organisation inspected the helicopter on the day of the accident. The fuel system showed no anomalies, with sufficient fuel of the correct grade in both bladder tanks. Flight control continuity could not be established due to fractured pitch links at the lower rod end, which exhibited characteristics consistent with overload fractures. The pilot’s throttle twist grip was found in the full “ON” position, and the collective pitch lever was near the full UP position. Examination of the tail rotor components found them to be in a serviceable condition with no evidence of pre-impact failures. The engine governor system and cylinder compression were assessed as serviceable at the accident site.