The crew were presented with all sorts of conflicting warnings, including airspeed warnings, the stick-shaker-stall warning, an Anti-Ice warning and so on.
They did identify, amongst all that, that they were in a runaway stab trim situation, and did disable the electronic trim (and MCAS).
However, disabling the trim does not return it to normal, it just stops any further automatic trim inputs from moving the stabiliser, and the only way to get the aircraft back into trim is to use the manual trim wheels, which are much lower geared than the electronic version.
Additionally, the aerodynamic forces on the stabiliser at the speed the aircraft was travelling appear to have made the manual trim almost impossible to move. Given that the crew were already having to pull back on the yokes with considerable force to counteract the nose-down attitude, they were unable to correct the trim manually.
It appears that they may have then re-enabled the electronic trim to try and use the yoke-mounted trim buttons, but then MCAS kicked in and added further nose-down trim, sealing their fate.
Biting the hand that feeds IT
