I don't think there is anything wrong with the leathality in AH. I'm a mechanical engineer and have done some aerodyamic computer simulations in my time (programming in fortran sucked

).
To put things into perpective...
You can simulate a/c turn rates, climb rates, lift drag, bullet drop, bullet energy, etc etc, and that is all relatively easy with the equations.
However, there isn't a computer built (or at least not one that the average Joe can afford) that can do real time finite element analysis (FEA) on the components being hit and what damage is actually be inflicted on them. Let alone do it in a multiplayer environment.
So, what you do to accomodate the lack of computer power is apply a generic SWAG factor to the individual component of the a/c and say
If component X receives Y amount of energy from a round(s), component X falls off. The more energy a round has (i.e round size and range) determines how many it takes to make a particular part fall off. Thus making is possible to take a tail off of a jug w/ 1 20mm or 10 20 mm at 400 yards. It becomes simply a factor of energy and an educated guess. Best you can do IMO. I don't know if this is how AH does it, but that would be the way "I" would.
Don't change a thing.... I finally figgered out how to shoot
