What happened
On 11 November 2023, a private glider flight departing from Worcester Aerodrome encountered insufficient lift while navigating the Western Cape landscape. The pilot, operating an ASW-20F with registration ZS-GNK, was flying in visual meteorological conditions when they attempted to locate thermal activity near the Saronsberg and Witzenberg ridges.
After finding very little wind and no usable lift, the pilot decided to divert toward Tulbagh Aerodrome. During the transit, the aircraft lost altitude and became unable to reach the intended aerodrome. The pilot opted to perform a field landing in an area that appeared to be a freshly cut field. However, upon touchdown, the pilot discovered the vegetation was actually barley. The left wing caught the crop, causing the aircraft to ground loop and sustain substantial structural damage to the tail boom, lower left wing, and aileron. There were 0 fatalities and 0 injuries resulting from the event.
The investigation
The SACAA AIID investigation examined the aircraft's maintenance history and the pilot's flight parameters. The inquiry established that the aircraft had been flown several times after its Certificate of Release to Service (CRS) had expired on 8 October 2023. Consequently, the aircraft was not maintained in accordance with required regulations and was technically not in an airworthy condition at the time of the accident. Additionally, the investigation noted that the pilot did not initially report the accident to the AIID as required by civil aviation regulations; the authorities only became aware of the event during a subsequent airworthiness inspection.
Findings
- The primary cause of the accident was the absence of thermals, which led to a loss of altitude and necessitated the field landing.
- The ground loop was triggered when the left wing made contact with the barley crop during the landing sequence.
- The aircraft's Certificate of Release to Service had lapsed prior to the flight, rendering the aircraft unairworthy.
- The pilot's medical certificate and glider pilot licence were both valid at the time of the occurrence.