Salute!
I take issue about the definition used by takata:
A "deep stall" is a result of the loss of any elevator control due to the turbulent airflow generated by the wings. Not sure that this symptom could be applied to something else than a T-tail airframe.
As we have seen in my first post regarding this:
http://www.pprune.org/6432295-post772.html
Some "deep stalls" have nothing to do with turbulent airflow over the horizontal tail control surfaces. I even included a pitch moment chart to show how this happens in the Viper. I also flew the VooDoo, which did have a T-tail. We didn't have "turbulent" flow, we had the vortex from the main wing strike our high tail and the increased AoA "pitched" the nose up and then we tumbled!! Because we had normal static stability, it was not difficult to quickly recover using the drag chute, but we also were not in a deep stall following the violent pitch-up. We had an AoA protect feature that shook the stick and then applied 28 pounds of forward stick if you kept pulling. However, you could "beat the system" with pitch rate at fairly slow speeds.
It could be the c.g. I tellya!!! If that plane had a c.g. further back than it normally used, the thing could easily settle into a fairly stable deep stall if its pitch attitude was steep and then it ran outta air molecules for the tail to work with - just like the Viper. Further, as with the Viper, the reversionary control laws allow lots more forward tail movement command using the control stick than aft stick commands.
The data plots are gonna be real interesting, and I am willing to bet folks will blame the crew.
respectfully,
Gums sends...