Emirates changes procedures after tailstrike

Emirates has begun using a second cockpit laptop to crosscheck flight crews' data calculations for take offs following the A340-500 tailstrike at Melbourne in March.

The Australian Transport Safety Bureau (ATSB) has released its preliminary report and the procedure change was revealed by the lead Australian investigator following the March 21 accident.

Director of Aviation Safety Investigation, Julian Walsh said: "Emirates has advised the ATSB that although there are a number of layers that are required to provide physical cross-checks during these calculations, in the interests of prudence, and until the circumstances are better understood, they have introduced a further level of independent cross-checking through the use of a second laptop computer."

The ATSB reported detailed how the crew entered an incorrect take off weight that was some 100t below the correct weight of around 362t into the electronic flight bag. Because of the incorrect calculations the aircraft’s thrust settings and reference speeds were too low.

The handling pilot at the time was the First Officer and notably both pilots had more than 8,000 hours total time. The handling pilot tried unsuccessfully to rotate the aircraft upon the Captain’s rotate call and when the aircraft did not respond the Captain applied Take Off/Go Around power to lift off in the grass area beyond the threshold. During the aircraft’s overrun it struck a runway light and damaged an ILS antenna. Subsequently investigators have identified three separate tailstrikes on the runway and two contacts in the overrun.

Walsh said that at this stage in the investigation the ATSB does not think pilot fatigue was a factor. He also defended the use of reduced power take offs, which are commonly used to help reduce engine wear.

The investigators have said that the investigation is continuing and will look at human performance and organisational risk controls that will include data entry, a review of similar accidents and incidents and systems and processes relation to performance calculations.

It will also look at computer-based flight performance planning that includes the effectiveness of the human interface of computer based planning tools.

Reduced power take offs are also going to be examined and investigators will look at the risks associated and how they are managed. As well as the crew’s ability to match aircraft performance with required take off performance and the associated decision making of the flight crew. Lastly it will investigate preventative methods with a focus on technology as the answer.

In the meantime Emirates has informed the ATSB that as a result of internal investigations the airline is reviewing its procedures.

The airline is looking at its human factors including a review of current pre-departure, runway performance calculation and cross-check procedures; to determine if additional enhancements is feasible and desirable, with particular regard to error tolerances and human factors issues.

On the training side it is to look at the initial and recurrent training in relation to mixed fleet flying and human factors.

While on its fleet technical and procedures side the airline is to review the possibility of introducing a performance calculation and verification system, which will protect against single data source entry error by allowing at least two independent calculations

Finally the carrier will look at its hardware and software technology, which will include liaising with technology providers regarding systems for detecting abnormal take off performance.

The following pictures are those released in the report and show the various levels of damage that the aircraft sustained.

Contact marks following the tailstrikes