Dozywannabe
It didn't budge because it never received a command requiring it to. In the sim, the trim wheel movement and behaviour seemed akin to a curve - with full nose down it started moving after a second or two, and had returned to neutral 8 seconds later.
In the case of AF447, the only time full-ND was held on the sidestick for more than a fraction of a second came right at the end by the PNF, and was counteracted by the PF pulling full-back on his.
Remember that 8 seconds to THS neutral has the elevators commanded to full ND throughout.
My understanding as a fully paid up SLF with bus driver friends, is that the THS movement is
not commanded in automatic operation, but operates to reduce the stress on the elevator hinges so it motors to the position that requires no further elevator deflection to maintain the 1g flight path. As has been said earlier if you reduce the power the THS will try to keep the nose high enough to maintain the 1g flight path all the way into the stall.
447 however did not enter the stall in the classic straight and level gently slowing down manner. The aircraft was in a rapid climb to above its flight envelope and thrust ceiling converting kinetic energy to potential energy. There is no prestall buffet or normal handling effects if you pull into a hammer-head stall or tail slide this was not far short of that. The resultant loss of aerodynamic lift as the aircraft ballooned over the top with negative g, gave the THS algorithms something perhaps that had never been considered likely.
Once set up in the stable nose up stall the wrong side of the drag curve in TOGA with a descent speed that was almost as much as the forward speed, there might be insufficient aerodynamic pressure on the elevators even in the down position to get the THS to move. Therefore it would remain fully nose up until (or if) the aircraft responded and started nose down. That may have taken idle/idle and nose down and held down till 30 or 40 degrees nose down attitude till airspeed was regained. That would be something an ex-military pilot might do but totally inconceivable for the 'must loose minimum height' never aerobatted, C-150, C172, PA-44, CRJ, Bus trained pilot. And of course every time there was an attempt to nose down the stall warning sounded and strangely the crew appear to have taken notice of it in descent having disregarded it previously.
This is not a case of playing in simulators, if the real aircraft algorithms fail then the simulator will be unable to replicate the effect. Someone needs to get an out to grass A330 on the way to a boneyard and actually replicate what happened. Good VFR with a clear horizon over uninhabited desert or sea just the thing for a test pilot to try. After all the experienced pilots here (and the engineers) are of the strongly held opinion it was only the fumblings of a poorly trained crew that caused the crash they would have recovered and flown home like the 30+ other reported UAS incidents. Even the engineers here think they could have recovered it after two or three simulator sessions. So there is no risk is there
go fly a real A330 through the same maneuver at FL380 show the world how its done and get real information on how the THS behaves dropping at 11,000fpm in a stable stall.