If used properly, the Yak 9T will take out a Panzer in one pass. Above and behind into the engine compartment, right behind the turret, the "sweet spot". Just got to make sure your shots are pretty much in the same spot. It's a safe bet that it's the same with the Panther. Don't know if it can be done in 1 pass though as I haven't had the chance to up one against it yet. M4's and T-34's will require more passes and don't bother against the Tiger. I, personally, like using the Hurri 2D though if there are quite a few gv's, the IL-2 is your best bet as it holds a lot more ammo and has F3 mode. I don't use the 25H as often, but it can do quite a bit of damage when used properly but is a pretty big target and not as nimble as the other listed planes. The P-39 is one plane I have yet to use in a tank busting role, though it's 37mm is the same as the 9T's in that it uses HE rounds. When it comes to armor, the 39 is better than the 9T and if it's 37mm is at least as good, then it should better in a tank busting role. Gotta up a P-39 next time there are some gv's running around.