Piper PA23-250 ZS-NWO Apron Collision at Benoni/Brakpan Aerodrome

Accident Overview and Location On 30 January 2008, a Piper PA23-250 with registration ZS-NWO was involved in an accident on the apron at Benoni/Brakpan Aerodrome (FABB). The aircraft was operating a training flight and had departed from and was returning to the same aerodrome. The accident occurred at 0945Z. ## Flight History and Sequence of Events The flight instructor and a pilot under training returned from the East Rand general flying area, where they had been conducting conversion training for the pilot onto the Piper PA23-250 type. After landing on runway 18, they turned off the runway onto the taxiway at the end of the runway. The instructor stated that they proceeded on the taxiway while he debriefed the pilot on her approach and landing. The aircraft was brought to a complete stop at the yellow 'T' (designated parking area) on the apron in front of the flying school's clubhouse. The pilot then applied the park brake and commenced with the aircraft shutdown procedures. The instructor noticed that the aircraft was moving forward. He immediately instructed the pilot to apply brakes, as the aircraft only had brake pedals on the left-hand side. She replied that she was, but the aircraft continued to move forward. The instructor insisted again that she must apply brakes, and she indicated that she was applying maximum braking. The instructor then closed the mixture controls on both engines; however, the aircraft kept on moving forward until it impacted with two vehicles that were parked on and next to the apron. ## Injuries and Damage The instructor and the pilot sustained no injuries. The aircraft sustained damage to the left-hand wing, both propellers, and both engines. Damage was also caused to a vehicle that was parked on the apron area and to another vehicle that was parked on grass next to the apron. ## Personnel Information The flight instructor was a 33-year-old South African male holding a valid commercial licence. His total flying hours were 1,313.4, with 67.0 hours on type. He was converted as an instructor on the Piper PA23-250 aircraft type on 1 November 2007. The pilot under training was a 20-year-old South African female holding a valid commercial licence. Her total flying hours were 206.40, with 6.35 hours on type. She started with a twin conversion rating training on 12 January 2008, and at the time of the accident had a total of 6.35 flying hours on the aircraft type. ## Aircraft Information The aircraft was a Piper PA23-250, serial number 27-2243, manufactured in 1962. The total airframe hours at the time of the accident were 10,582.53. The last mandatory periodic inspection (MPI) was certified on 13 November 2007 at 10,517.75 airframe hours. At the time of the accident, the aircraft had accumulated a further 64.78 airframe hours since the last MPI was certified. The left-hand engine was a Lycoming O-540 A1D5, serial number L-15095-40, with 978.30 hours since overhaul. The left-hand propeller was a Hartzell HC-A2VK-2, serial number H2589, with 355.32 hours since overhaul. The right-hand engine was a Lycoming O-540 A1C5, serial number L-5660-40, with 697.82 hours since overhaul. The right-hand propeller was a Hartzell HC-A2VK-2, serial number H161, with 363.95 hours since overhaul. ## Meteorological Information Weather information was obtained from the pilot's questionnaire. The wind direction was 090° at 5 kts, the temperature was 24°C, the dew point was 10°C, and visibility was CAVOK. There was no cloud cover or cloud base. ## Probable Cause The pilot under training allowed the aircraft to move forward on the apron area and the aircraft collided with two vehicles that were parked on and near the apron area. Contributory remarks included that the pilot under training stepped on the rudder pedals instead of the brakes, and the flight instructor failed to intervene soon enough in shutting down the engines.