Comanche 4

Comanche 4 is the fourth incarnation of Novalogic's helicopter simulation Comanche. This time, the game uses a real 3D environment (no voxels) and has easier gameplay. There are six brand new campaigns; you'll get to fight in cities as well as deserts or even Arctica.

If you want to play against your friends, that's no problem: Comanche 4 supports up to 16 players at once in LAN or Internet play.