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Re:Boeing Built Deadly Assumptions into 737 Max, Blind to a ... by sokoloff on Saturday June 01, 2019 @08:43PM (#20072735)
I believe the airplane is aerodynamically stable even at high alpha. What it fails in certification is the requirement to have continually increasing pitch feedback forces. I believe the pitch feedback forces are still in the stable region, just too low. This is not a flying wing or intentionally unstable airplane (as the F-16).
Re:Boeing Built Deadly Assumptions into 737 Max, Blind to a ... by inferiorhuman on Saturday June 01, 2019 @09:27PM (#20072892)
I believe the airplane is aerodynamically stable even at high alpha.

That would put you at odds with Boeing's test pilots.

Re:Boeing Built Deadly Assumptions into 737 Max, Blind to a ... by sokoloff on Sunday June 02, 2019 @04:27AM (#20074222)
No it wouldn't (or "citation needed" if so).

The issue is not that the airplane shows negative or neutral aerodynamic pitch stability, it's that it does not exhibit an increasing stick force gradient, as required by certification rules.

https://airfactsjournal.com/2019/03/can-boeing-trust-pilots/

Re:Boeing Built Deadly Assumptions into 737 Max, Blind to a ... by leoc on Saturday June 01, 2019 @08:53PM (#20072772)
>> [...] In most of the flight envelope the aircraft is stable.

>> At high alpha the aircraft has pitch problems.

> I believe the airplane is aerodynamically stable even at high alpha. [...] This is not a flying wing or intentionally unstable airplane (as the F-16).

In some ways that's likely worse news than an airplane that's inherently unstable in general, no? A corner case, and one that evidently isn't actually all that uncommon. If you're building something like an F-16 you know that you absolutely have to make the fly-by-wire correct and robust, and the ground crews similarly know that if anything affects its performance the plane isn't fit to fly.