Bell 430 Accident at Spartan Helistop, Kempton Park (ZS-VDM)

Flight Details and Accident Sequence On 22 April 2017, a Bell 430 helicopter, registration ZS-VDM, operated by National Airways Corporation, departed Grand Central Aerodrome (FAGC) in Gauteng Province for a private positioning flight to Spartan Helistop in Kempton Park. The flight was conducted under Part 91 regulations. The pilot-in-command, a 30-year-old female commercial pilot with 1,480 total hours and 91.3 hours on type, was accompanied by a passenger who was also a helicopter pilot but not type-rated on the Bell 430. The passenger, seated in the left front cockpit, provided visual guidance for the approach and landing, as this was the pilot's first landing at the helistop. The helicopter approached from the south into a 360°/6kt wind. After an initial overflight to inspect the site, the pilot executed a second approach and landed on the demarcated helistop. Upon touchdown, the helicopter began rolling forward slowly due to a slight downslope on the right-hand side of the landing area. The pilot applied toe brakes, which had no effect, and did not apply the park brake. In an attempt to stop the forward movement, the pilot applied aft cyclic to tilt the main rotor thrust backward. ## Damage and Investigation Findings Following the application of aft cyclic, the helicopter shook violently, bounced, and rotated 90° along its vertical axis. The pilot closed the throttles and shut down the engines to prevent fire. Both occupants exited the aircraft without injury. The investigation determined that the excessive aft cyclic input caused a substantial aft tilt of the main rotor disk, resulting in the main rotor blades contacting the left vertical stabilizer and severing the tail boom. The helicopter sustained extensive damage to the main rotor transmission, transmission platform, tail boom structure, and main rotor blades. A section of a main rotor blade separated and caused minor damage to nearby vegetation and a residential fencing wall. The helicopter was declared not economically repairable. ## Probable Cause The probable cause was the pilot's application of excessive aft cyclic in an attempt to stop the helicopter from rolling forward, which caused the main rotor blades to contact the left vertical stabilizer and sever the tail boom.