Originally Posted by
derjodel
So, you just took off, engines still at TO power, you retract the flaps... and start fighting Mcas as per above description. No time to manage engine power so you are gaining speed...
you remember mcas. Somehow you pull the circuir breaker. With both pilots pulling the stick the plane now goes into a steep climb. Followed by stall, and crash due to unsuccessful recovery...
Could it match, in theory?
Could be correct.
You see after take off the normal speed-trim system is always trimming anyway, so you are used to that 1930s (borrowed from the Ju-52) trim-wheel clanking and rotating. So it may take you a while to realise the trim is doing something very wrong.
Plus if the MCAS system is at fault again, you will have the stick shaker going off, which makes a hell of a racket, and is not cancellable. The stick shaker is supposed to be transient, just for the stall, but if yet another AoA vane has failed, the shaker will go off continuously, and is a serious distraction.
Plus you go for the stab-trim cutout switches, and you forget they are down for off, while all the other switches on the 737 are up for off. (Why is Boeing so stupid...?) So you shout to the f/o, above the noise of the shaker and the trimmer, 'did you turn the stab-tim switches off', to which he-she replies 'yes' - meaning he placed the switches upwards. But this turns the trim on, not off.
And then you reduce power, and the huge thrust-couple change plunges the nose downwards. So now the aircraft now has full trim forward, and is plunging to the ground like a home-sick troglodyte. (When does an aircraft ever want full trim?) And two people pulling on the stick is no longer sufficient to stop the dive. And Boeing thinks this is a great system to fit to a modern airliner, and a great ergonomic design for the 21st century? I have got news for Boeing....
And yes, this discussion
is justified, because Boeing never gave any answers to the last crash. And nor, so far as I know, have they made any amendments to MCAS. So the 737-Max is
still fitted with a system that will give full trim forward, and make the aircraft uncontrollable. Why is that? Does Boeing have an explanation for this - for why any aircraft would want full trim forward while pulling out of a stall's subsequent dive??
Silver
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