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Old 3rd Jan 2010, 20:54
  #2702 (permalink)  
suninmyeyes
 
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Mis-dagin

My comments were based on my experience of recreating it in a simulator several times and 2nd hand reports from the guys who were at the front.

The flight data recorder did not show the final up elevator movements as it stopped recording before impact.

In the recreation we attempted to deal with it as though we were not expecting it. We failed to make the runway on all attempts and ended up pretty much in the same position. There is only about 30 seconds from first recognising a problem to hitting the ground and the first 15 seconds or so is spent trying to evaluate the problem and there is a sense of disbelief that neither engine is responding. The EGTs are normal and uniform and there is no Eicas indication of engine failure.

The low speed protection you refer to is only valid with the autopilot engaged. With the autopilot disengaged there is an autothrottle wake up which would have been of no use as it simply advances the thrust levers which had already been advanced but the engines had not responded.

A flap 25 approach requires less thrust than a flap 30 approach and faced with a loss of thrust with flap 30 extended there is an instinct to raise the flap by one stage. In a normal goaround on the 777 even from 50 feet you still immediately retract the flap from 30-20 or from 25-20 even before you have obtained a positive climb because the sink is negligible and there is a reduction of drag.

In the recreation there is a high rate of descent before touchdown but it is fairly instinctive to initiate the flare early and commensurate with the ground rush rather than the radalt calls. To raise the nose and arrest the descent rate requires a much greater application of up elevator than normal. Approaching the stall the elevator feel makes the elevator artificially heavier but if you pull a bit harder you can still obtain full up elevator and incredibly effect a touchdown IAS of just under 100 knots. We ended up with full up elevator on all touchdowns and I understand this is what happened for real.

Just bear in mind that only one passenger was injured. I believe that was because they got the flare exactly right. Without that the result may have looked like the Turkish 737 at AMS. Well done chaps.
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