What happened
On 22 November 1999, a Pitts Special S-2B, registered as ZS-MMZ, was conducting a private flight south of Johannesburg. The aircraft departed from Rand Airport at 09:47 Z, carrying a pilot and one passenger.
Around 10:00 Z, an eyewitness observing cattle in the Kliprivier district noted the aircraft performing various aerobatic maneuvers, including vertical climbs and rolls. During one of these maneuvers, the aircraft attempted a stall turn at the apex of a climb. Following this, the aircraft began a rapid descent, oscillating slightly between left and right banks. The aircraft was unable to recover from this high-rate descent and struck the ground in a wings-level attitude approximately 11 nm South South West of Rand Airport. The impact caused the aircraft to slide 32 meters before stopping. While the main fuel tank ruptured, no post-crash fire occurred. Both occupants sustained fatal injuries.
The investigation
The investigation focused on the flight path and the sequence of maneuvers leading to the impact. Investigators examined the witness testimony regarding the vertical climbs and rolls, as well as the aircraft's behavior during the descent. The inquiry also considered environmental and physical factors, specifically how the aircraft's weight and the prevailing density altitude might have influenced engine and aerodynamic performance during high-stress maneuvers.