Originally Posted by Yankee Whisky
The aircraft was flying fully nose up elevator(stick input as well) at low speed and, I would have thought that when a pilot pushes fullynosedown,thebloody elevator WILL travelfullynose down in QUICK succession.!!! In my days of flying I had to use full controls on many occasions, both in normal and in spin or landing round-outs. PWhy must modern pilots be deprived of this when the sh"t hits the fan, as was the case with AF447 ?
It loooks like Airbus tried to copy in the 80's the F-16 flight management system with a g feedback. Which information had they? Who gave the information? Was is public? (The flight law are still under industrial secret) Were spies at work?
Despite Airbus is using the word "protection" against excessive g (2.5!!!) I suspect the idea was to increase passengers comfort in LIGHT TURBULENCE holding g to 1... In the 80's automation fashion started to have interest to limit sound or vibration with "bruit blanc".
Using the feedback to maintain g to 1 was such a path to realize that goal : limit oscillation of the airliner. (In which point of the plane is a second problem...)
But when the system is piloting z`` with feedback you have to use the stick not to control the elevator but the tendance of the elevator (Airbus S/S action)and you have to integrate the signal in the direct path. The pitch trim does the same work to maintain g=1, not the speed, and is "protecting" (limiting) against quick full nose down.(not a god idea!)