Airliner data input error shows importance of checklists and cross checks in aviation operations

The Australian Transport Safety Bureau is emphasising the need for adherence to standard operating procedures, after a Dash 8 turboprop airliner departed with incorrect take-off data when a fuel miscalculation was not detected in pre-flight checks.

On 15 January 2021, a QantasLink Dash-8-315 aircraft had landed at Tamworth, New South Wales, and was being prepared for a return to Sydney with two flight crew, two cabin crew, and 29 passengers on board.

In the Dash-8-315, the quantities displayed on fuel tank gauges for Tank 1 and Tank 2 must be manually added together by the flight crew to get a total fuel reading.

While finalising records for the flight which had just been completed, the first officer incorrectly calculated the total fuel on board to be about 340 kg more than the actual quantity.

This error was not detected by the captain during cross checks, and the inaccurate flight record was submitted electronically.

Moving on to pre-flight procedure for the return trip to Sydney, the flight crew then relied on this incorrect mental model of the aircraft’s fuel state, rather than physically verifying the fuel quantity once again.

While going through the ‘before start’ checklist with the first officer, the captain recalled looking at the fuel gauges for the fuel quantity check, but again relied on memory to read out the fuel figure.

This resulted in the aircraft departing Tamworth with inaccurate load, take-off and fuel management data. The error was not detected by the flight crew until the aircraft reached cruise level, when it was corrected, and the flight continued without further incident.

“Thankfully, the data input error did not result in any abnormality during take-off or climb in this case,” ATSB Director Transport Safety Stuart Macleod said.

“But it is a lesson in the importance of adhering to standard operating procedures, as well as clear and concise communication, and independent cross checks between pilots.”

Data input error is one of the ATSB’s eight ‘most wanted’ safety concerns, as part of the SafetyWatch initiative.

“Flight crews can guard against errors by applying effective threat and error management strategies that recognise when such threats may arise, and put in place suitable actions to minimise error potential,” Mr Macleod said.

Following the incident, QantasLink provided internal communications to flight crew on checklist usage and cross checking of data. QantasLink also intends using the incident as a case study in its human factors/non-technical skills training program.

You can find here the report: Fuel data occurrence involving Bombardier Dash-8-315, VH-TQE Tamworth Regional Airport, New South Wales, on 15 January 2021

Last update 30 September 2021

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