Approximately 20 minutes after departure, the crew was advised that a pallet weighing 3,696 kg, which had been included in the load/trim calculations, was not on the aircraft. This resulted in the aircraft's centre of gravity being slightly rear of the calculated position, but still within required limits.
The airline's normal practice was to operate a Boeing 747 on the Nagoya service. However, on this occasion the service was operated by a Boeing 767. The pallet which had not been loaded was purpose-built by the shipper to optimise the available space on Boeing 747 aircraft. Its design included an extension at each end which precluded loading through the cargo compartment door of Boeing 767 aircraft. Communications within the operator's freight system provided early notification of the aircraft change. However, this information was not provided to the shipper. The operator's freight section at Cairns, when receiving the pallet, did not recognise its unsuitability.
In preparation for loading the aircraft at Cairns, the leading hand loader was provided a Load Instruction Report (LIR). The LIR showed the load distribution of the aircraft on arrival, and the load distribution for departure as required by the load controller. A third section of the LIR was to be completed by the leading hand following loading to confirm the actual load distribution on departure. The LIR would then be passed to the load controller. Aircraft had, on occasions, departed before the load controller received the LIR.
On finding that the pallet could not be loaded, the leading hand advised the load controller who was on the flight deck at the time. The controller checked the pallet and indicated to the leading hand that by rearranging other containers, it could be loaded. However, the high noise environment of the loading area made conversation difficult, and the controller did not remain to ensure that the pallet could be loaded. He left the aircraft satisfied that the problem was resolved without the need to amend the loading documentation. The leading hand assumed that the load controller recognised that the pallet could not be loaded, and directed that it be returned to the freight shed.
The aircraft departed before the controller received the amended LIR which indicated that the pallet had not been loaded.