Originally Posted by PEI_3721
CONF, I can appreciate that there would not be any trim-follow-up (as in manual flight) whist the AP was engaged. However from page 1 of the report, with the AP engaged (9 29 50) back stick appeared to result in nose down THS, possibly due to an autopilot generated trim demand to balance the opposing stick input.
So we don't have a similar appreciation of the situation, as thrust increase and its pitch up effect + speed increase alone justify the THS nose down movement to properly trim for the negative pitch necessary for the aircraft to follow the GS.