Air Niugini Flight 2100

Investigation

The investigation was carried out by the Papua New Guinea Accident Investigation Commission (PNGAIC). The investigation revealed that the aircraft was overloaded. The ATR 42F had cargo compartments assigned in alphabetical order from the front, and was divided into six compartments designated with the letters AF. The flight was carrying 340 cartons of cigarettes and, according to the load sheet prepared on the day of the accident, aircraft A was to be loaded with 350 kg, aircraft B and aircraft D with 800 kg each, aircraft E with 600 kg and aircraft F with 360 kg. The person responsible for loading, who had prepared this sheet, had not measured the actual weight but had calculated that each box weighed 12 kg, giving a total cargo weight of 3,710 kg. However, the actual weight of each loaded box of the three brands was 12.14 kg, 12.44 kg and 13.16 kg respectively, which made the aircraft heavier than expected.

The actual weight of the cargo is unknown, as most of it was taken home by residents before the investigation began, but it is estimated to have been 4,303 kg based on the per-box weight mentioned above. This is 593 kg more than the value calculated by the manager. In addition, the cigarette manufacturer's employee who witnessed the loading memorised the number of cartons of each brand of cigarettes loaded in section A and, based on this, when the loading situation in section A was recreated, it turned out to be 1,136 kg. This is 786 kg more than the 350 kg indicated on the load sheet and 136 kg more than the maximum permitted weight of 1,000 kg for that compartment. As described above, the aircraft had been loaded more than expected, with a total weight of 17,243 kg, that is, 343 kg more than the maximum take-off weight of 16,900 kg. The centre of gravity was also not within the safe range.