Originally Posted by
Smythe
You are stuck on stick forces, and how it feels to the pilot....what about AP? Does MCAS operate with AP on?
I am not "stuck on" stick forces. Stick forces are simply what MCAS was designed to modify, so that is where the discussion should be focused. You are making the (incorrect) leap that the demonstrated nonlinear stick forces equate to negative static stability. Those are two distinct issues. Show me any data which indicates that the pitch angle would have
kept increasing if the controls were released, and then perhaps you would have evidence to support your position. Until then, throwing out assertions that the design was "unstable" are not supportable.
The AP cannot handle the stall, or that would have been added to the algorithms in the AP, right?
I'm not aware of
any autopilot that can handle a stall. Maybe one exists, but I've never seen one. Generally the automation is set up to keep far away from the stall environment, but there are ways to induce them into flying an aircraft into a stall. In those case, the autopilot will disconnect.
You did not address the issue of the discontinuity or disruption of the airflow over the wing which causes stall. From what is written, it obviously introduces stall at a much lower AoA than previous variants, and much lower AoA then was designed for (hence a software patch)
The fact that one can stall a 737 is not in dispute. I don't know if it stalls at a lower AOA or not, but that has nothing to do with stability.