Originally posted by Con_fiture
Simply because you omit the necessary initial conditions :
"Additionally, in these high angle of attack situations, with a tendency towards phugoid movement, studied by longitudinal stability, in which the aeroplane oscillates between two kinetic and potential energy levels"
Initial conditions are irrelevant - the system must be stable for any initial condition and in any atmospheric conditions.
If you want confirmation that phugoid oscillations between two kinetic and energy levels can exist without there being any turbulence just look at the graph that HN39 posted recently. That had at best neutral stability and had no additional phugoid damping - there was no turbulence present. It shows why the phugoid damping terms are necessary.
The point about the software changes made after Bilbao, which you seem to have misunderstood, was that they were made to prevent unnecessary engagement of Alpha Protection in turbulent conditions. The laws that govern the motion once Alpha Protection is engaged have been unchanged from the word go. Other than the logic governing the point of entry into alphaprot
the same laws were in place at Habsheim as at Bilbao.
You are simply adding confusion by trying to conflate the two events.
You seem to be using the fact that the system description I quoted came out of the Bilbao report to suggest that it ( the system description) is somehow not applicable for Habsheim. Can we go back to discussing that accident and maybe you could tell us where/why you think the system as described in the Bilbao report, especially that part that describes the effect of speed feedback does not apply for Habsheim? For example, do you have any positive evidence that the basic laws were changed after Habsheim and before Bilbao?