Tail?
Dennis,
WHAT can you be thinking???

Purely as an academic exercise, I was considering and contrasting the relative merits and aerodynamic characteristics of the swept vertical stabilizer (at a 33 degree sweep from the relative wind) verses the standard vertical stabilizer at a 90 degree angle to the relative wind on our birds. Naturally, the greater side area on the newer birds (which had the height of the stabilzer increased approximately six inches with a commensurate increase in total area) will provide enhanced controllability particularly at slower speeds and greater angles or atack should one attempt an unusual maneuver uch as a slip or any maneuvers requiring rotation about the vertical axis of the craft while in an airborne configuation. Applying the fundamental elemental principles of fluid dynamics provides us many interesting and challenging scenarios.
Of course you can't ever have too much tail (feathers).
Oh my...