Error Causes Emirates A340 Tail Scrape

Incorrect weight data on an in-flight computer caused the tail of an Emirates Airbus A340 (A6-ERG) to scrape the runway during takeoff March 20, 2009 from the Melbourne Airport, according to Australian Transport Safety Board (ATSB) officials. The Dubai-bound jetliner was forced to make an emergency landing an hour after taking off. There were no injuries among the 257 passengers and 18 crewmembers on board Flight EK407, but plane's tail was seriously damaged from being dragged along the tarmac. The ATSB’s preliminary findings determined that during the takeoff roll on Runway 16, the captain called for the first officer to rotate. However, when the aircraft was slow to respond, the captain commanded and applied maximum take-off thrust. The aircraft's tail struck the runway and the aircraft lifted off shortly afterwards. During the takeoff, the aircraft's tail contacted the ground beyond the end of the runway and a number of airport landing aids came into contact with the aircraft. After becoming airborne, the flight crew received a cockpit message that a tail strike had occurred. They contacted Air Traffic Control and requested a return to Melbourne. The aircraft was radar vectored over Port Philip Bay to dump fuel to reduce the aircraft's weight for landing. “While reviewing the aircraft's performance documentation in preparation for landing, the crew noticed that an incorrect weight had been inadvertently entered into the laptop when completing the take-off performance calculation prior to departure. The performance calculations were based on a take-off weight that was 100 tons below the actual takeoff weight of the aircraft. The result of that incorrect takeoff weight was to produce a thrust setting and takeoff reference speeds that were lower than those required for the aircraft's actual weight,” the ATSB report states. The ATSB did not say how the wrong number came to be entered into the computer or why the crew failed to pick up the error in cross-checks.