There's no evidence that it would have made any difference at all. The ET302 crew was too overwhelmed by a stall warning to cut the autothrottle and still worked hard, against the stall warning memory item checklist to enable the autopilot. An extra warning light on the dash when they weren't looking at the instruments to begin with would have been equally easily ignored.
Originally Posted by
WideScreen
Not sure if your writing is to "defend" the Boeing statements that "just switching off the electrical trim" using the trim cut-out switches is suitable to control the aircraft, but just reading your "instructions" makes me wondering, how pilots should be able to find out the need to do so, within seconds the cacophony started and let alone decide which actions to perform.
Not to say, IF the instruction to apply manual trim every 10 seconds, during the remainder of the flight, in case of an AoA sensor failure, to avoid an imminent crash, would have made it to the memorized instruction list, the whole MCAS disaster would have been unfolded before the first 737MAX take-off and MCAS design returned to the drawing board.
It was literally what crew #1 and the captain of crew #2 did - applying manual trim when the trim loads became noticeable at a few pounds, prior to any prompting by the documentation that was delivered shortly after the FO of crew #2 didn't. Trim cutout switches have been in place for several decades. Were pilots required to diagnose a wiring fault or an STS software failure prior to using the cutout switches back then?
No one called for any heads to roll until the owner of the plane that crew #3 controlled claimed that crew #3 followed every step exactly as laid out in the emergency AD and demanded that following those instructions was not enough to avoid a crash. That claim turned out to be entirely untrue, but was only revealed a full year later with the preliminary report. It certainly seems to me that everyone operating the 737, and the MAX in particular, accepted the AD as sufficient until then. Was there any testimony to Congress to the contrary?
For decades, pilots weren't all rigorously trained to deal with unwanted trim system actuation, certainly not in conjunction with any other problem. For decades it was OK to issue false stall warnings and stick-shaker activation. MCAS merely exposed that there had been no safety net on those two fronts for a long time.
What I am pointing out is that there are and have been systemic issues that extended far beyond Boeing and that sole focus on Boeing and MCAS is an incomplete lesson to learn.