Enemy airships are approaching your command base! You need to fly your five plane squadron into battle to defend it. Tac-Scan is a conversion of the arcade game. You control a squadron of five ships at the bottom of the screen, your goal is to earn as many points as possible by destroying the various enemies which will be attacking. If one of the ships in your squadron is hit by enemy fire, it will be destroyed. The game ends when all five ships have been destroyed. As you progress through the game, you will occasionally have the chance to replenish missing ships. Everytime you complete a round by shooting ten enemies, an extra ship will float by on the screen. You can add this ship to your squadron by catching it in an empty space in the formation. Every time you complete four rounds, the game will advance to the next level with increased difficulty!