So on final to RWY07L @ LEBL in a 34% load 787-9 I smoothly intercepted LOC about 15nm out and the glideslope at 3000 ft AAL. The autopilot has a difficult time maintaining the ILS path as the crosswinds are pretty strong (~22 kts from the front-right all the way to 200 ft), so at about 700 ft to the threshold and fully configured (flaps 30, IAS: 138 kts, gear down, spoilers armed, trim +50% bc thats what it took to get rid of the pink bar) I attempt to disengage autopilot settings one by one (first vertical speed, then HDG, then SPD, and finally I attempt to disengage APPR all together about 150 ft AAL (by tapping “APPR”… My plane rockets upwards for about 10 sec till I finally regain control ~1600 ft.
thing is I calibrated just before disengaging everything, and my v/s was disengaged prior to deactivating entire APPR…how do I properly prevent my plane from losing the path immediately after autopilot disengaged? Same thing happens if I disengage entire APPR in one step. I suddenly lose control. Should I not use APPR and try to use autopilot inputs to follow the ILS path to a certain point? or should calibration just before disengagement work well and Im just somehow doing it wrong? lol
oh and I realize it’s a somewhat late A/P deactivation but the instability happens whenever I take control