Why is it that a A20 with a load of bombs can out turn a fighter?
Because the fighter pilot sucks.
No, that's not just a smartass reply. A fully loaded A-20 has a very mediocre turn radius and turn rate, most fighters do much better (not to speak of power/ acceleration). If the A-20 outturns and shoots down a fighter, the fighter pilot messed it up. (Yes, I have also messed it up more than once and fell to the A-20
)
Planes have their strengths and limitations. But it depends on the pilot to exploit the potential performance. I have flatly outturned Spitfires and Ki-84s in my Ta-152, but that doesn't mean the Ta 152 "outturns a Spit". I outturned the enemy pilot, who was not able to utilize the maximum turning performance of his plane. If flown to the performance limit, both planes go circles around the TA 152.
A competently flown A-20, in a
light configuration can surprise the unsuspecting, average fighter pilot, outfly and shoot him down. But you can only take it so far.
If you suspect "bad modeling", I'm afraid you will have to present your case with more substance, i.e. technical details and actual numbers. (By the way, turn radius and turn rates in game can be objectively tested and compared)
