The IL-2 is the only plane I've blown up panzers in without having to dive on them from a steepish angle. Usually a relatively flat strafing run of ~20 degrees or so if enough to kill a panzer in a IL-2.
Can the IL-2 kill a Tiger? I know the Hurri-2D can knock out the turret on one, so I'd assume it could actually kill it given enough time and luck, but I've never actually done it.