QantasLink Plane Avoided Potentially Serious Incident

4th Oct 2016

QantasLink plane carrying 91 passenger and five crew members on 20th June this year from Canberra to Sydney avoided a potentially serious incident, says a report from the Australian Transport Safety Bureau (ATSB).

The ATSB said in an official report regarding this incident that the use of inaccurate takeoff reference data could have potentially serious consequences.

According to the ATSB investigation, the incident occurred when the pilot, operating a Boeing 717-200 aircraft between Canberra and Sydney initially prepared for a "flex" takeoff on an assumed temperature of 39 degrees Celsius outside. Later, however, as 22 new passengers boarded the plane, the flex temperature was reduced to 34 degrees Celsius.

Flex temperature allows the pilot to use reduced thrust for plane takeoff, lowering the wear and tear on its engines.

The captain recorded the new temperature over the initial one (39C) and then used that one to calculate the engine's required thrust.

Fortunately, the plane took off and finished its journey to Sydney without any trouble.

The investigation by the ATSB found that both the pilot and his co-pilot assessed that tiredness from their early morning start could have led to the flex temperature error. The two flight crew members however added they were fit to work for the rest of the day.

The ATSB report said:

"The flight crew commented that a combination of distraction by cabin crew and ground personnel while re-entering data, a reduced state of arousal following a high workload instrument ?approach, and possibly tiredness from an early start may have contributed to their omitting to enter the correct flex temperature."

In a report from a few years ago (2011), ATSB warned about the consequences of using incorrect data for flight calculations. Back then, ATSB said this can lead to runway overruns, tail strikes and an overall degradation of handling qualities.

ATSB also said:

"It is imperative that the aviation industry continues to explore solutions to, firstly, minimize the opportunities for takeoff performance parameter errors from occurring and, secondly, maximize the chance that any errors that do occur are ?detected and/or do not lead to negative consequences."