OK I *think* I know the answer to this but before i go spouting off i figure I would ask.
The minimum drag on a airplane in 1 g flight occurs at what is known as the "best climb" speed in here, since that is where the most excess power is available for climb (it is the point of minimum combined induced,skin friction,form, and wave drag).
Sooo, if you go level flight, reduce power setings to where you are only maintaining that speed (the best climb speed) if power is cut any more, it should not be possible to maintain that altitude, even if you are well over stall speed right? Since as speed decreases, your drag increases (because of the larger induced drag dominating the relative small skin friction and form drag)and your plane should drop.
Is that right? Im 99% sure it is. Question, is is that how it happens in AH? Might be my computer is defragging so i can't test it