[tus88]

> The 737 airframe is actually relatively stable compared to many other things that fly

Nice strawman. We are talking about the MAX not the 737 in general.

Why don't you explain why previous variants of the 737 didn't require MCAS?

[VBprogrammer]

Why don't you explain why previous 737 versions have a Mach trim to prevent Mach tuck, or why it had a speed trim system to control the pitch force response to speed changes.

[tus88]

For the same reasons it has control surfaces at all. Planes need to adjust their aerodynamic properties in order to adapt to various external and intrinsic factors. Trim in particular maintains aerodynamic stability in the presence of some conflux of the two.

The trim equivalent of MCAS would be some elevator trim that ensures the excess AOA potential of the MAX could not occur, if set correctly. That is how a stable aircraft behaves. MCAS is a computer override to compensate for a condition that should not really occur in the first place.