I don't know how to fix it . I am how ever saying it is beyond unrealistic . I think the way to fix it would be the optics .
So what do you propose?
I have seen it mentioned that the main gun optics incorporated a focussing mechanism. When the target was in focus, you had a pretty accurate distance to target by looking at the sight meter ( much akin, I would surmise, to the distance marks on a camera lens).
So.. the image through the gunsight would have to be blurry until you focussed the sight to remove the blur. Even while not in focus, however, the target would be a blur of some type ( unless well hidden with skin and gound effects ). As long as this blur exists, the gun can be pointed at it. Unless you're talking about extreme ranges, the target won't be transparent.
So.. we've got a gunsight that calibrates distance based on focal point. Oh goody. Now, when I see an aircraft coming at me, I'm going to swing around.. get him in the sight, set my calibration to 400 yards and wait for him to almost be in focus.. fire.. and, suddenly, my AA accuracy has increased exponentially.
Now.. that may be complete malarky. Sounds plausible to me, however.
Bottom line.. don't fly down the barrel of a tank.
<edit> After consideration.. how pronounced would the non-focussed blur be? I'm recalling how my macro lens can't pick out details enough to discern a target until the focussing mechanism gets close. How fine are the optics of a tank sight? If they are as sensitive as camera lenses, it may be a challenge to even find a GV in the clutter.