I'm looking for a old game. I think I first saw it in 1997, maybe 1998. In this game I played a tank or a chopper that had a home where you start the mission and enemy base that you had to destroy. When a building was destroyed a square with a letter would replace it: I remember F for Fuel and A for Ammo. After each mission you get money and can buy upgrades. Terrain was snow or desert. The game was 2D or 2D with shadows (2.5D). View angle was from above. Platform is PC. Thanks for your help.