@ China and Peter an others......
One mo' time about FBW.
The MCAS moved the horzontal stab to keep the pitch moment of the beast within the FAA cert requirements. That is not a minor "tweak" of the plane's natural aero stability. A computer controlled movement of the elevator at the rear of the stab would have been "minor". Planes since the early 60's have had flight control "dampers" and "augmentation" to help we lowly pilots that get you there on time and maybe smooth things out a bit. The FBW Airbus and the military jets are not in the same arena with the 737 MAX.
The MAX problem was not "feel" from the longitudinal control system, it was the actual tendency of the plane to increase pitch at the same back stick or at least require less back stick when getting above a certain AoA. When I say back stick feel, what I mean is your plane wants to do something it normally does with "x" pound/ounces of pressure or movement, but now requires less or actually requires an opposite movement/pressure/force. The FAA requirement requires more "pull" as you try to get the nose up and increase the AoA. Dat's why the MCAS used the AoA probe and not body rates, Q, inertial gee, etc. Somewhere in there Boeing found that mach contributed to the pitch tendency and then increased the overall "gain" that MCAS exercised, then they had the damned thing keep pushing doen for "x" reps/seconds/whatever. Sheesh!
FBW systems vary as to the amount of "help" they can provide the "technicians" we now have flying the jets, but I cannot find any civilian commercial systems that depend upon the computers to correct for unconventional aero that we see in some military fighters requiring severe maneuverability. Those rascals have different operational requirements and most do not have 200 SLF's depending upon them to get to Detroit. The Airbus 330 aero design is so good that the crew of AF447 did not even realize they were deeply stalled ( not a "deep stall"). Go see the thousands of posts about that debacle and then you will conclude the system did exactly what it was designed to do given the air data provided to the computer and the pilot stick inputs.
FBW is not a magic bullet, and should not be used to compensate for poor aero design.
Last edited by gums; 3rd Dec 2020 at 02:34.
Reason: typo; conclusion