How would one evaluate the elevator authority of a design? I'm still having a hard time wrapping my head around control derivatives, but I assume they're the key here. I suppose you just look at dCm/delevator (or whatever you want to call it; AVL seems to use Cmd1). If so, what's a reasonable target for a cross-country small plane? Going a bit wider, what are reasonable "goal" values for the various stability derivatives in different phases of flight?
