Originally Posted by
RetiredF4
This aircraft would under your definition of the NZ law maintain pitch attitude, but go into an descent to compensate for the loss of speed. It would be partial speed stable. It would not stall from level flight and it would not try to maintain altitude.
Hmmm, I don't see the disagreement with BEA in my post. If you put the aircraft in an attitude where the thrust is not sufficent to sustain the speed it will progressively continue into a stall. That is what BEA basically says.
Edit: Maybe just to clarify: When I say attitude I refer to pitch and not to AoA.
edit2: I assume the notion of Flight Path in BEA's description might be a traslation thing. Per my understanding the FCS does not care about Flight Path in the proper sense. That's the FMS which does that. FCS cares about behaviour relative to the air, not navigational.
Let's assume you place the nose 10° above the horizon. My understanding is it will try to keep the nose pointed at 10° no matter what the AoA. Given the fact that thrust will not be sufficient at that altitude to maintain speed in that attitude and given the progressively increasing drag with decreasing speed it will go into the stall and will resist any natural tendency to drop the nose with elevator and once its authority limit is reached it will call the trim for help.
Could you point my to where my assumption differs from BEA's?