What happened
On July 31, 2001, a PA36-375, registration ZS-KHR, was conducting a training flight near Koringberg Aerodrome. The pilot had departed from Koringberg with the intention of returning to the same airfield after practicing crop spraying maneuvers in a nearby practice area. During the operation, the aircraft encountered gusting winds influenced by the local hilly terrain, which subsequently escalated into severe wind shear.
In response to the deteriorating flight conditions, the pilot initiated a precautionary landing in an open, grass-covered field. While the aircraft avoided a high-impact crash, the landing was heavy. During the touchdown, the propeller struck the ground, and the tail wheel assembly suffered a spring fracture. At the time of the incident, the aircraft was carrying a 400kg load of grain-type fertilizer, which the pilot was unable to discharge quickly due to the low altitude and proximity to the ground.
The investigation
The investigation focused on the environmental conditions and the mechanical state of the aircraft. Meteorological data at the time indicated fine weather with temperatures of +30°C and surface winds of 30kph. The aircraft, which had a total airframe time of 7419 hours, had recently undergone a Mandatory Periodic Inspection (MPI) on July 26, 2001, having flown only 29 hours since that maintenance event.
Findings
- The primary factor in the emergency landing was the encounter with a down-draught, a phenomenon common in mountainous or hilly regions during gusty conditions.
- The pilot executed a precautionary landing to avoid the hazards of the wind shear.
- The heavy nature of the landing resulted in a propeller strike and structural damage to the tail wheel assembly.
- There were no injuries to the pilot during the event.