Originally Posted by
lomapaseo
There seems to be in this thread an early fixation on a previously known cause. This flies in the face of the ability of the industry to assimilate previous causes and promulgate corrective actions world wide.
What do you expect? MCAS is a cheap (and semi-back-door) stick pusher system. It is far from ideal, but was a simple software change rather than a complete new stick-push system, which is what should have been fitted. Face facts, MCAS was a hurried and ill-thought-out fix, to yet another upgrade to a 60-year old airframe - and it is known to have already caused one tragic loss, iin very similar circumstances to the oresent incident. You think it is not justified to bring up the MCAS system again - because I have not heard that the system has been changed in any way. It is still sitting there, like a brooding gremlin, ready to pluck aircraft out of the sky at any minute.
And Boeing have still not explained the logic of of a pseudo-stick-push that keeps operating again and again and again, until you get full forward trim. Have you tried this MCAS-trim-runaway in the sim? According to the sim, the aircraft is only just about controllable with two gorillas hauling back in unison, with both feet up on the foot-bar and hauling about 40 kg pressure on each stick. And that was in level flight with the CofG in the central position. Ok, now try a recovery from a stall-dive, with a forward CofG, with 20º nose down pitch, and with the speed rapidly increasing to 250 kt. It is absolutely impossible - you are doomed. And doomed by an anti-stall system that is supposed to save you. But who in the world would want to recover from a stall, with the trim-stabiliser set fully forward? Who thought that ine up? The stabiliser is more powerful than the elevator, and will take you straight down to terra-firma. Heck, even the Wright Brothers knew not to design something like that.
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