Microsoft Combat Flight Simulator 3: Battle for Europe

From the publisher:

As a pilot in Microsoft Combat Flight Simulator 3, you fly in the historical framework of the tactical air war in northwest Europe starting in mid-1943, but there’s a significant difference. The skill and perseverance you and your squadron or Staffel bring to each battle can alter the tactical situation and the timeline of the campaign. This open-ended and flexible campaign means you can influence events, alter history, and extend the timeline to add new technology to your arsenal. How you handle these tactical and technological advantages will determine the outcome.