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Old 18th Jul 2011, 13:42
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Gretchenfrage
 
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I did not specifically pretend that the crews involved were former AB pilots and inexperienced.
I described a trend that led to the MD11 being decried difficult.

The tendency to flip on its back after bounced landings originates due to the partial deployment of the spoilers after wheel spin-up (first contact). If this occurs hard and a bounce follows, the aircraft hangs in the air with mostly quite high pitch and thrust idle. As I mentioned, the MD11 has a particularly steep rise of the speed/drag curve below Vref, therefore stalling rapidly in this situation. One wing does this first (mainly downwind) and a marked banking occurs and the wing touches the ground leading to the flip.

Remedy was to select one notch less flaps (still landing configuration) or keep the Vapp, or even Vapp+5 down to TD. This is however not always desired, as the Vapp were already very high with full flaps. Not really what you'd like especially on shorter runways (i.e. the one in NRT), those less than 2500m were not very appreciated with this bird.

Another very important remedy is a ultra strict flight path adherence on short final. This assured a much more constant pitch and trim configuration. You needed to assist/override the AT to keep a precise approach speed adherence, less to the upper side, but absolute to the lower. That is exactly where Airbus pilots were less precise (in my experience), their former birds (I have flown them as well) are much less delicate in this respect. The speeds were lower, they mostly flew fixed throttles and the Airbus' are less traitorous when slightly below Vref.
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