Accident Overview
On 7 March 2016 at approximately 1410Z, a Piper PA-28-140 registration ZS-EXV crashed while attempting a forced landing at Mountain View Aerodrome (FAMV) in Gauteng Province, South Africa. The aircraft was operated by Sky Hawk Aviation under Part 141 training rules. The flight originated from Lanseria International Airport (FALA) with a planned destination of Wonderboom Aerodrome (FAWB). On board were a flight instructor (aged 27, Commercial Pilot licence, 510.6 total hours) and a student pilot (aged 31, Private Pilot licence). The instructor was seated in the right seat and the student in the left seat.
Flight History
The take-off from Runway 07 at FALA was uneventful. After departure, the aircraft executed a left turnout climbing to 5500 ft AMSL. At approximately 1408Z, the student made an outbound call on the FALA frequency (124.0 MHz) using the incorrect callsign "XXV" instead of "EXV". The air traffic controller (ATC) did not correct the callsign but instructed the pilot to broadcast intentions on the outbound frequency 125.8 MHz. About two minutes later, at 1410Z, the student transmitted "MAYDAY" three times on 124.0 MHz (instead of 125.8 MHz), again with the wrong callsign. The ATC acknowledged and asked the student to report the type of emergency. The student stated they were trying to reach Mountain View Aerodrome (FAMV) but did not respond to the request for the emergency type.
Engine Failure and Forced Landing
The aircraft experienced an in-flight engine failure. The pilot attempted an emergency landing at FAMV but was unable to reach the runway. The aircraft touched down approximately 100 metres short of the threshold of Runway 25 on grass-covered terrain. During the landing, the aircraft bounced and then impacted rocky terrain about 90 metres short of the runway. A post-impact fire erupted, destroying the aircraft. Both occupants were fatally injured by impact forces and the fire. The ATC observed smoke in the direction of FAMV and alerted fire services.
Witness Statement
A witness Aircraft Maintenance Engineer (AME) who had been working at FALA reported that earlier on the same day, he heard an unusual knocking sound from the engine of ZS-EXV as it taxied past. He informed the student pilot, who acknowledged the issue. The AME also spoke to the instructor. After the engine was shut down and restarted, the knocking persisted. The student later started the engine again for the accident flight.
Investigation Findings
The on-site investigation determined that the engine failure resulted from a connecting rod small end bushing failure. The root cause of the bushing failure could not be determined. The aircraft was destroyed by the impact and subsequent fire.
Probable Cause
The probable cause stated by the investigation is: "Unsuccessful forced landing due to the aircraft experienced in flight engine failure as a result of connecting rod small end bushing failure, the cause of the bushing failure could not be determined. The Pilot attempted to do emergency landing however the aircraft landed approximately 100m short of the runway, during forced landing the aircraft landed hard and bounced and it was destroyed by post impact fire."