Why didn’t they pull back? They clearly could not
Earlier in the thread it was mentioned that with an a very nose trim as
speed increased it may become impossible to overcome the (large) trim with (small) elevator, even with
both pilots using full force (h/t
Centaurus, post #
826, FCTM air load warning with nose down trim)
*** PURE SPECULATION No data to support ***: The contention would be that at some point the crew actually did use the stab trim cutout switches, leaving them with only manual wound (literally by hand, extremely slow), trim and elevator for pitch control, there was an IAS increase which reached an uncontrollable speed.
As I said, this possible chain of events is purely speculative based upon the previous sector having an AoA anomaly, the Boeing Bulletin,
APA MCAS revelation and a little bit of supposition. Thus far the data does not contradict this speculation, but I reserve the right to be wrong as new facts emerge.