Pre-flight planning event - Boeing 737-476, VH-TJL, Melbourne Airport, Victoria, on 22 November 2011

On 22 November 2011, during pre-flight performance calculations at Melbourne Airport, the crew of a Qantas Airways Boeing B737-476 aircraft, registered VH-TJL, inadvertently used the full-length runway 16 distance to calculate the take-off performance figures despite planning a runway 16/taxiway Echo intersection departure. Neither crew identified the error, which produced inappropriately high take-off reference speeds. During the take-off run the crew realised there was inaccuracy in the figures and elected to continue the take-off, rotating the aircraft below the calculated rotation speed (V_R). The error was attributed to the Electronic Flight Bag (EFB) menu structure defaulting to the full runway length.

As a result of this incident, Qantas Airlines advised that they have modified the EFB to require a positive selection of the runway length. The application of correct operating data is a foundational and critical element of flight safety, but errors in the calculation, entry and checking of data are not uncommon. The ATSB has published a research report that addresses the issue.