Originally Posted by
JPcont
One problem could be that regulators have taken closer look the actual implementation rather than definitions in the paper work. MCAS is clearly more AoA (stall prevention ) related feature than maneuvering characteristics related feature. It might be that the regulator expects that it is certified as such.
The MCAS measures the AoA and so it tries to control AoA due the feedback measurement it uses. As far as I have understand, the stall depends mostly on AoA and less on Reynolds and even less other factors (in a specific plane). The “stick force augmentation” is only a side effect of MCAS control law. The system dynamics and fluid mechanics are not interested in the political naming convictions and they don't care economical consequences. They follow their own laws and don't care of our opinions. So, also we should care of the namings.If the aim really have been to emulate the “grandfather feeling”, the main feedback would have been the stick force (not AoA). The set point to the sick force would been calculated from AoA and other factors.
That kind of control law (with stick force limits) should have not force (with reasonable force limits) the plane ground even if the actuator were the stabilizer. I hope, the shortcuts are not allowed this time.
Is it accurate to say that MCAS is AoA stall prevention at all? How would it prevent a stall at all, in normal, non-malfunctioning conditions? It adds nose down trim, yes, while the A/P is off, but it doesn't really prevent stall, at best it gives the pilot a better trim condition for high AoA, which might enable the pilot to prevent a stall. Just asking. MCAS does not make the 737 impossible to stall.