After a five-minute delay in securing the aft cargo door, the Boeing 737 was cleared for pushback. The ground engineer then passed a message to the crew to 'call control' but gave no indication of urgency. The crew decided to concentrate on the departure and to call control when airborne.
After take-off, the crew contacted Load Control and were advised that the load controller had been attempting to make contact to inform them that the load sheet may have been inaccurate. The crew were not warned via the ACARS data communication system before take-off. The crew had not been monitoring the Load Control frequency as they had already received the final load sheet. Aircraft performance and handling were not affected.
Investigation revealed that the leading hand of the loading gang had given a 'Ramp Clearance' to the load controller while the loading of the cargo hold was still in progress. The 'Ramp Clearance' indicated to the load controller that either all compartments had been loaded as required, or that the entire load had been accounted for and was either alongside the aircraft or in transit to the aircraft. However, due to unserviceable webbing in the doorway of compartment 4 of the aft cargo hold, the loading gang relocated 10 bags to compartment 3 of the aft hold after the leading hand had given the 'Ramp Clearance' and the load controller had sent the final load sheet to the aircraft.
The leading hand advised the load controller of the change, and the load controller amended the load calculations. The load controller then attempted to contact the crew on the Load Control frequency, without success, as the crew were not monitoring the frequency. The load controller then contacted Movement Control in Cairns to have the ground engineer attending the departure, ask the crew to 'call control'. The engineer passed the message, but the crew did not contact Load Control until after take-off. Thus, the aircraft departed with the load sheet unamended.
Standard Operating Procedures for Load Control specified that ACARS messages should not be sent to the aircraft after the final load sheet was issued. This was based on the need to avoid distracting the crew performing vital actions during departure, plus the likelihood that the crew could miss the message. The load controller was required to inform the crew verbally of any late changes to the load sheet. In addition, when the company implemented its new load control system, management decided that due to cockpit workload, crews would be required to monitor only two frequencies (Air Traffic Control and Movement Control) during the period within 15 minutes of pushback.
Prior to the occurrence, the company had initiated a review of procedures relating to the issue of ramp clearances. Alternative procedures were being trialled. However, the new procedures were not a factor in the occurrence.
At the conclusion of the trials, new procedures were implemented in Melbourne in December 2000, and training was scheduled for February and March 2001 prior to implementation of the new procedures at other ports.