Originally Posted by
FCeng84
Hopefully Boeing will make the details of the MCAS modification clearer soon. MCAS in its original implementation would run again in the presence of AOA failed high following any amount of pilot pitch trim command. One can envision a modification to require that the pilot have run the trim back nose up at least a certain amount before allowing MCAS to go again. Or how about requiring that AOA drop low after having been high before allowing MCAS to go again. There are lots of things that could be done to provide additional interlocks. I am certain that we will learn that simply blipping trim with the revised logic will not trigger MCAS to reset to the point of running in another full increment of airplane nose down stabilizer motion.
From a programming point of view, having a system remember its previous state, and respond differently, creates all kinds of complexity. I would never want to go down that route, but can't see simple ways of avoiding the threat of multiple false MCAS activation, while still catering for repeated stalls.
Knowledge of the actual value of the trim stabiliser would be interesting, but I have not seen any mention of that as an input parameter.