The ATSB's Preliminary Aviation Safety Investigation Report into the 7 May 2005 Lockhart River accident in which two pilots and 13 passengers perished has found that the Metroliner had descended about 1000 ft below the minimum obstacle clearance altitude when it collided with terrain. The aircraft had cut a swath of less than 100 m through heavy timber on the steep slope.
Preliminary information recovered from the flight data recorder and on-site examination of components indicates that both engines were producing about 30 to 35% torque. This is consistent with an approach power setting.
The aircraft was en route from Bamaga to Cairns via Lockhart River. The weather conditions in the Lockhart River area at the time of the accident were reported by the Bureau of Meteorology and people at Lockhart River as being broken low cloud with squally showers and drizzle. The crew reported that they were conducting the instrument approach to runway 12. It is unclear which of the two pilots was flying the aircraft at the time of the accident.
The wreckage was located in the Iron Range National Park about 90 ft below a 1300 ft tree covered ridge on the north-west slope of South Pap, a hill approximately 11 km north-west of Lockhart River on the final instrument approach track for runway 12.
The flight data recorder contained approximately 100 hours of useful data which has been assessed as being of reasonably good quality and contains data relating to the accident flight. Preliminary analysis of the data indicates that the aircraft had been descending at a constant rate, but with some turbulence evident, over the 50 seconds prior to the impact.
One of two former senior pilots who resigned from Transair PNG in mid 2002, who had previously raised some concerns about alleged regulatory breaches in PNG, has advised the ATSB that he has no knowledge of the accident and believes he cannot help the investigation. The other pilot has provided the ATSB with no information relevant to this investigation.
The investigation is continuing and will include analysis of recorded data, collation and analysis of operational, maintenance and regulatory records, other data and statements, recovered instruments and analysis of instrument approach procedures. The ATSB will release an Interim Factual Aviation Safety Investigation Report by December 2005.
Copies of the Preliminary Aviation Safety Investigation Report 200501977 can be downloaded from the website.