The
Australian Transport Safety Bureau (ATSB) opened an investigation into the accident. Most of the wreckage of the aircraft was raised on 4 January 2018. The intermediate report, published on 31 January 2018, indicated that the aircraft was found to have followed a differing flight path from the usual, and had failed to climb to the necessary altitude needed to fly over the surrounding terrain. It also indicated that the preliminary examination of aircraft flight control surfaces and controls seemed in sound order and expected positions, and that the engine sounded normal to witnesses on the ground. The aircraft landed inverted and all six on board suffered fatal injuries. On 28 January 2021, the ATSB released a final report into the accident, which concluded that the pilot and passengers had higher than normal levels of
carboxyhaemoglobin in their blood. Additionally, several pre-existing cracks in the exhaust collector ring very likely released exhaust gas into the engine/accessory bay; gas very likely entered the cabin through holes in the main firewall where three bolts were missing from the magneto access panels. The aircraft was fitted with a disposable CO detector, but CO detectors of its kind have been widely deemed unreliable. The operators of the aircraft have implemented changes to the aircraft's system of maintenance, which include: • The aircraft being fitted with active electronic CO detectors. • The check of the serviceability of the CO detectors has been incorporated into the monthly emergency equipment checklist. • Directing its new maintenance provider that the removal and installation of the main firewall access panels must be classified as a critical maintenance operation task, and will require certification by a licensed aircraft maintenance engineer and a conformity inspection. • Directing its new maintenance provider that following maintenance activities on the engine exhaust system or use of the main firewall access panels, the test for the presence of CO must be conducted. • An inspection of the magneto access panels and CO testing has been incorporated into the 100-hourly 'B' check inspection. == In popular culture ==