What happened
On the morning of 24 May 2000, a Grumman AA-1B, registration ZS-WZE, departed from Wonderboom Airport as part of a flight plan that included stops at Pietersburg and Phalaborwa. The mission was a private flight intended to collect a passenger from Phalaborwa.
During the return leg of the journey, while flying abeam Middelburg, the pilot noticed the engine was running roughly. In an attempt to rectify the issue, the pilot engaged the carburettor heat and activated the fuel pump, which provided partial relief to the engine's performance. Upon contacting Wonderboom for landing instructions, the pilot was instructed to enter an orbit east of the Roodeport dam. During this holding pattern, the engine's condition deteriorated significantly. Despite further attempts to use carburettor heat and switching to an alternative fuel tank, the engine eventually suffered a total failure.
The pilot was forced to perform an emergency landing in a grassy field located approximately 3 NM east of Wonderboom. During the landing maneuver, the aircraft overran the field and struck an embankment. While there were 0 fatalities, both occupants sustained minor injuries.
The investigation
The investigation focused on the sequence of engine malfunctions and the pilot's corrective actions during the flight. Investigators examined the pilot's use of the fuel pump and carburettor heat, as well as the transition between fuel tanks, to determine why the engine's rough running could not be stabilized during the holding pattern near Roodeplaat dam.