henra
howdy. The BEA report "a" left, nose up input. Not continuous. Doesn't the 30s mimic a rate similar to Manual? IOW, .65 degree/second? That gives a total of 20 degrees NU, but with some pauses on the way up, why not a total of Ten total excursion in 30 sec.? How would the THS "know" when to calibrate its rate? Maneuvering and cruise are separate in what way? (To the THS)? Is it not "On" or "Off"? If in Auto, (it was), then it is the FCS that did the inputs, and if not in response to PF, then what was the "Goal"?
If, at a/p drop, the THS was at a trimmed 3 degrees (It's "starting" point), then ten degrees is the total excursion from cruise trim, and we know that the a/c did NOT immediately start to climb, per BEA. This lack of Pitch response is trying to say something, post PF input ("I have the controls").
If unresponsive to PF's initial inputs, would he not increase the input? If ten seconds later, the THS would now have trimmed seven degrees NU? What took the a/c so "long" to start "climbing"? Imagine that, a 150 ton a/c at 350 being "unresponsive". Any vertical acceleration that resulted in 7k fpm climb would be a belly cruncher, and he would have countered the zoom with ND, without question. What made the A340 reluctant to drop her nose in Caraibes? Two conscious and trained pilots would not allow such a climb, and if they could not control it, why?
It is in this climb that some mechanical and/or FCS transient seems to appear. One must grant to each "system" a basic trust in its abilities? To include the Pilots, eh?
Last edited by bearfoil; 8th July 2011 at 17:35.