Originally Posted by gums
And if we were using otto, we expected some indication that otto had trimmed the plane versus us. So any reversion from automated flight to manual flight should not require instantaneous analysis of what the hell is going on.
Look at the graphs cyan curves I posted above: graph 6 "Position PHR" = THS setting, and graph 7 "Position gouverne de profondeur gauche" = Left Elevator setting. Now, compare them.
As expected, THS is not following short term g-load elevator demands. During the whole sequence, 0209:40 - 0210:54, THS setting is changing from -2.8° to -3.4° (negative = NU)... hence a maximum variation of less than 0.6° in 1.14 minute. During this whole sequence, the long term pitch demand increased from about 3° NU to 11°NU, with up and down in between.
Stall warnings, sounded at 0210:51 and stall followed 10 seconds later. From this point, the large NU demand was confirmed both in amplitude and in duration by elevator ncrease up to Max NU deflection, and they were mostly maintained here during the following minute. Consequently, THS followed its order by moving in the very same way up to Max NU deflection.
There is absolutely no mystery about that:
OTTO had NOT trimmed the plane versus pilot demand !!
- OTTO only did what it was asked to do!
Of course, this end result, with hindsight, is contrary to the good setting for a rapid recovery action... but
nobody really wanted to recover from this situation at the first place!