Accident Overview
On 24 January 2022 at 1043Z, a Jabiru J400 (registration ZU-DFP) was conducting circuit flights and touch-and-go landings at Krugersdorp Airport (FAKR) in Gauteng province. The pilot, who held a commercial pilot licence and had 1666.7 total flying hours with 97.2 hours on type, was accompanied by a passenger. The flight was to assess the aircraft's performance for the passenger, who had recently purchased it.
Sequence of Events
Prior to the accident, the pilot had completed three approaches on Runway 08. During the fourth approach at approximately 50 knots, the aircraft was stable and touched down with a tailwind. After touchdown, the pilot applied brakes but the aircraft did not decelerate. The engine revolutions per minute (rpm) were higher than usual despite positive back pressure on the throttle, and the pilot was unable to retard the throttle fully. To avoid overrunning the runway, the pilot applied right rudder. The aircraft then flipped over onto an inverted position in a small open field to the right of the runway, where it came to rest. Neither the pilot nor the passenger were injured, but the aircraft sustained substantial damage.
Findings
The passenger reported that during the landing the aircraft seemed to 'float' down the runway and touched down before the halfway mark. Runway 08 is 848 meters long. The aircraft touched down approximately 384 meters from the threshold, leaving about 464 meters to the opposite threshold (Runway 26). The required landing distance for a Jabiru J400 is 520 meters; thus, an additional 56 meters were needed for a safe stop. The pilot had approximately 70 meters remaining after the Runway 26 threshold but could not bring the aircraft to a halt and elected to turn right.
Maintenance and Inspection
The last maintenance inspection before the accident was performed on 8 December 2021 at 3871.1 airframe hours. A Certificate of Release to Service was issued on the same date, valid until 8 December 2022 or 3971 hours. The accident flight was the first flight after that inspection. After the accident, the aircraft was taken to the Jabiru factory where the throttle was inspected and found to be in proper working order.
Probable Cause
The aircraft was unstable on approach, resulting in the aircraft touching down with the tailwind just before the middle of the runway; the pilot could not bring the aircraft to a safe stop in the remaining runway and, therefore, applied right rudder without success in an attempt to avoid overshooting the runway.