Originally Posted by grity
the stick move of first 10 sec. after AP disconect 2:10:07 --- 2:10:18
the moves are more or less horizontal so I think he did not realise that he pulled, just fight with the rolling ship....left right left right left right.... realising that he had no longer correct speed at this time
Graph by grity
Initial grip to the SS was with the intention to counter the roll to the right. Thereby he overcontrolled or he chased the roll like in an PIO. During each reversal from left to right or vv PF induced a pitch change as well.
The initial grip had also a big NU input, which brought the plane of the later left / right movements considerably in the NU region, with only two considerable ND inputs but only enough to reach the neutral SS pitch position.
The assumption, that those NU inputs where associated with the aim to climb to a higher FL is IMHO obsolete (i didnīt believe in it anyway). PF might have intended to counter a sinking tendency as described by
hazelnuts39, but i meanwhile doubt that.
The whole mess might as well have started with
- not being prepared for the situation
- being surprised by the dropout of AP + ATHR,
- PF gripping SS in a hastily and unsuitable mannor
- and thereby implementing unwanted and anneccessary steering inputs
- chasing the roll and missing the pitch (PNF might have noticed it)
- and loosing instrument cross check and SA all together
- and PNF on the LH seat not seeing the need to take over
- or not willing due to expierience in LH seat LH SS
- stall warning triggered the TOGA initiation in PFīs intinctive reaction
- and pitch control stayed as bad as before.
Was the seat position not suitable for the correct operation of SS?
Training issues had been mentioned month before already.
Unfortunately the graphs in the report are not good quality, i hope they show up some time in a higher resolution. There i a lot of info in them, and we will have lots of discussions about them.
In Phase 3, there are a few points where vertical speed goes close to zero, in one time at 02:14:15 (page 113 of the report) and also some 17 sec. before that it even shows positive climb.
Other times descent rate is more than 15.000 fpm.
Do we know, that those values are valid indications or are those values wrong?
It will be much enlighting to understand the behaviour of the crew in phase 3, because most probably their reactions based on things they saw. If those above mentioned VV values are correct, then they saw a drastic increase of descent rate when pitching down and a reduction of descent rate when pitching up with TOGA, with the expectation to get the ship flying again. We know that they had been stalled completely and that this increase in descent rate was a necessary tradeoff to achieve recovery, they probably didnīt.