>Computers should never overrule manual controls.
I disagree. I've got all kinds of examples were on conventional cable/hydraulic control to control surface aircraft a pilot can overstress the airframe, break it, and crash. If a computer were to exactly know the normal flight envelope, and always proscribe inputs that lead to certain death? I'm all for that. And what does manual control even mean with fly-by-wire airplanes?
>If the autopilot is on and the pilot makes an manual adjustment to the yoke, the autopilot shuts off.
That isn't how it works since the simplest roll only autopilots appeared. It seems a reasonable argument that a single pilot should be able to overpower the autopilot long enough to disable it.
>They should have designed the MCAS system to recognize when the pilot was fighting it and to disable itself.
Unproven. Could be true or false.
Boeing has a different design philosophy than Airbus whereby they include the pilot as integrated into system design, as the primary means of determining system failures. I have no inside information, however I can imagine that MCAS is intentionally designed to only accept one sensor input for two reasons: it's simpler, and you get a fast fail in the form of what appears to be runaway trim for which there is already a procedure to follow.
I have two concerns with this though:
a. The reported optional pay for (?) "aoa disagree" feature which does no decoupling of MCAS, but informs pilots when the alpha vanes disagree. I think that should be standard, not optional.
b. MCAS silently disabling itself is potentially very dangerous even if the 737 MAX required a separate type rating, but it's possibly a great deal worse given that it does not require a separate type rating. MCAS is the thing that inhibits the natural stall behavior of the MAX, a natural stall behavior the pilots aren't trained to recognize or mitigate or recover from because they aren't supposed to get anywhere near this portion of the flight envelope - it's why MCAS exists. Take away MCAS and now its an open question whether the pilots are properly certified for that aircraft or whether the plane is not airworthy, suddenly while in-flight.