I'm not suggesting that they're actually adjusting the range in the gun sight, but having the icon displaying the range it makes it easier to figure the right amount of elevation to give gun to counter the drop.
Again, I have not issue with tanks gunning down a plane that's flying right towards it at low level. My issue are tanks gunning down planes that are not a threat to the tank or one very close by.
Understood. However, the range does little (IMHO does nothing) in giving anybody an advantage. The majority of kill shots are taken from under 1k - 1.5k there is little adjustment in elevation required at this range (more or less put your site at the same elevation) up to the max vertical angle of the Main Gun. The difficulty at least for me - is in finding the proper lead of the moving target.
How are GVs to distinguish between what is a threat and was is not? Yes, you can see two guys Dog fighting at low level, the next minute one is strafing you or another friend is pointing you out. The reasonable solution? If an aircraft is low enough to be shot at - they get shot at. It is just as frustrating for GVs to get bombed when they are having a tank battle w/ no intention or ability to take a base. This has been going on since the day they introduced GVs. Its a fact of AH and my vote is to leave it as is.
Top down approaches on tanks at all times. Nothing needs to be fixed except attack strategy. 
Agreed. This is the solution to the OPs concern.
Waystin, Atlau, NOTAR and few others know how to adjust their attack so as to stay just above the Max elevation of the Tanks gun. Without a Whirb or M16 near by the GV is in an indefensible position. I hate them. . . . .lol
