Campaign Difficulty

Does anyone flying CFS3 have issues with the campaign model flying as an American? I must be doing something wrong because even when I fly 95% successful missions against Germany, in late 1943 the campaign falls apart and Germany invades England and the campaign ends with a screenshot of me weeping by my decommisioned aircraft. Aarrghh!
I love the simulator for what it is, and I thoroughly enjoy CFS2, but I would really like a campaign model in CFS3 that makes sense. Are there any CFS3 veterans out there that can shed some light on what I might be doing wrong as an American? I have tried every combination I can think of to make a positive effect on the front line, but it always seems to favor Germany. Apparently, the Brits and the Jerries have a much easier time winning the campaigns. What's up?
Many thanks and watch your six.
I love the simulator for what it is, and I thoroughly enjoy CFS2, but I would really like a campaign model in CFS3 that makes sense. Are there any CFS3 veterans out there that can shed some light on what I might be doing wrong as an American? I have tried every combination I can think of to make a positive effect on the front line, but it always seems to favor Germany. Apparently, the Brits and the Jerries have a much easier time winning the campaigns. What's up?
Many thanks and watch your six.