During cruise, the Boeing 767 (B767) crew noticed that the fuel consumption was 230 kg per hour more than normal. After the cargo had been unloaded at the destination, the crew had the cargo re-weighed. The actual cargo weight was more than 3,400 kg greater than the weight stated on the manifest.
The operator reported that its investigation revealed that four pallets had been carried from Honolulu to Sydney and that all were heavier than the weights recorded on the manifest. The discrepancies were 2,277 kg, 887 kg, 220 kg, and 10 kg.
The two pallets with the greatest weight discrepancies had been transported from mainland USA in a freight aircraft operated by a US operator, and had been transferred at Honolulu to the B767 for onforwarding to Sydney. The weights stated on the pallet tags for the internal US leg were in pounds, but the B767 operator required the weights to be in kilograms. The agent who handled the freight for the US operator at Honolulu converted the weights from pounds to kilograms and pencilled in the converted weights on the deadload sheet for the Honolulu-to-Sydney flight.
When the agent who handled freight at Honolulu for the B767 operator received the pallet weights, she did not check the figures against the loadsheet issued by Load Control. Consequently, she did not realise that the weights stated on the loadsheet had already been converted to kilograms, and applied the conversion a second time. Also, as the agent for the US operator was confident that she had passed the correct weights to the B767 agent, she did not recheck to ensure that the B767 agent had received the correct weight information.
The 220 kg and 10 kg weight discrepancies affecting the other two pallets were probably the result of weighing or recording errors.
The B767 operator has since amended procedures for its agent at Honolulu. Under the new procedures, only the supervisor will carry out weight unit conversions and liaise with other operators' agents. This should minimise the risk of erroneous information being passed between agents and help to ensure that all required checks are carried out.
The B767 operator is monitoring the effectiveness of the new procedures.