Please HELP!!! Game from Windows 95-98 days. Game about tank and birds from nowhere.
I remember the story but not the name of the game. Player have a tank, the first mission begins in the desert (well, not a desert - there were hills everywhere - lets say a hilly area), the action is probably in the future. Also there are white crystals around - if you collect them - your tank can fly (yes , this tank can fly

) but ofcourse not for along time. At first everything is quite - in this desert there ere two zones - people everywhere , also they can sit inside the tank. Also we can see time - when it expires, everything becoming dark/green and out of nowhere alot of giant birds appear. Also I remember that at the end of this first mission if you want to pass to the second level - then you must to fly through the circles which are above the ground. I will be glad if someone could help me to remember the name of this game!
Thanks!