X-COM: Interceptor
X-COM Interceptor is the fourth game in the original X-COM series from Microprose. While it retains many of the strategic and business-focused elements of the original games, this particular entry has the men and women of X-COM fighting it out in outer space in real-time fighter combat, rather than on a turn-based planetary battlefield.
Concept
Keep the aliens from attacking your bases and outposts while trying to reveal their own bases and shipping lanes, so you can cripple their war efforts. Train pilots to fight on the front lines while continually upgrading and supplying your forces.