Emirates Airline Pilots Involved in Tail Strike Reported to Have Resigned

Posted on 22. Apr, 2009 by in Featured

It seems likely that the accident (tail strike) in Melbourne Australia was another case of pilot error. Sources reveal a 3 was entered incorrectly as a 2 in the gross weight entry of the aircrafts flight management system (FMS).

Airliners normally take off at a reduced power setting to preserve engine life. The required power setting and speeds for rotation and flap/slat retraction are based on the weight entered in the Airbus FMS. Most aircraft receive the numbers from the companies dispatch via load control and enter them manually. The Airbus 340 has an automated system that factors the speeds and power setting from entries made by the crew. A 3 mis-typed as a 2, means a 100,000 pound mistake (a 30% error in weight). Simply put the power would not be capable of accelerating the aircraft in accordance with set requirements. And the speeds reached (based on the flawed entry) would not be fast enough to enable the aircraft to fly.

The speeds are factored to allow: a. the aircraft to accelerate to a given speed (V-1); abort the takeoff and stop on the available runway. b. Or, past V-1 speed (unable to safely reject the take off) the aircraft is able to accelerate (with an engine out) to take off speed (VR) and then engine out speed in the initial climb (V-2) and also clear any obstacle at the end of the runway by 35 feet. A set of numbers that meet all of these parameters with no room to spare is called a balanced field, which means no room for error or delay in action.

These numbers are predicated on weight, temperature, pressure altitude, wind, and runway length. All are important; weight is the most critical. The crew was able to muscle the A-340 off of the ground as it ran out of runway. That is when the tail strike occurred; they narrowly missed a small building which would have meant disaster. 170 centimeters was the margin between life and death.

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