Accidents

Qantas Boeing 737 Loading

Default settings meant that children were incorrectly recorded as adults, resulting in incorrect aircraft weight and balance. Take-off safety speed was exceeded by about 25 knots.

On 9 May 2014, a Qantas Boeing 737 was preparing for departure from Canberra to Perth. There were  150 passengers, 87 of which were primary school children. These children were all seated together at the  rear of the cabin.

A ‘name template’ was completed by a travel agent on behalf of the school group. This group was travelling  from Perth to Canberra and returning back to Perth. Despite being marked as mandatory, the “Gender  Description” field in this template was left blank; options for this field were “Adult”, “Child” and “Infant”.

As per company procedures, two days before the Perth-Canberra leg of their journey this group was  ‘advance accepted’ into the booking system. Since the fields recording the number of children and young  passengers in the group were blank, the Customer Service Agent assumed all of the group were adults. No  loading-related issues were experienced during this flight.

Two days before the return flight the group was again “advance accepted” as all adults. This meant they  had all been assigned an ‘adult weight’ of 87 kg. They were checked in at Canberra Airport and assigned  seats at the rear of the aircraft. During take-off the aircraft appeared nose heavy. Significant back pressure  was required to rotate the aircraft and lift off from the runway. The aircraft exceeded the calculated take-off  safety speed by about 25 kt. The aircraft rose at a higher initial climb speed than usual, but the crew did  not receive any warnings. No further issues were experienced during the flight.

This incident demonstrates the importance of the completeness Data Property (i.e., ensuring that the  mandatory “Gender Description” field was completed) and the fidelity / representation Data Property (i.e.,  ensuring the calculated aircraft loads and balances reflect the real situation). It also illustrates some  potential difficulties associated with the use of default data.

Links 

http://www.atsb.gov.au/publications/investigation_reports/2014/aair/ao-2014-088.aspx
(accessed 29  November 2017).