Originally Posted by
clearedtocross
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So here we have an airplane design spec that was most likely not taking into account the aerodynamic behaviour of relocating the engines. I bet the problem was only detected after some test flying of the new airplane. So time runs out, a redesign of the aircraft is now impossible and so a software patch is called for to get better stall protection. The aircraft is not FBW and thus the triple redundancy and voting concept is neither required nor followed. And as all software engineers know, patches sometimes backfire because they have not been designed with the same care as the original system. Ask Bill Gates.
What I find hard to understand is why Boeing didn't elect to upgrade the Elevator Feel System for compensating this undesired aerodynamic behaviour and instead created a new MCAS software module in the FCC.