i don't know what is going on with the fighter sim games now.. i mean i can't find any good hits... i remember when jane's fighter simulators could run on my PIII system and how good it felt to be, then when i pop it in today (ok, so i misplaced it for a couple years......) and found the rich graohics bad, and went on the internet to search for more recent titles... and all i found was WWII based sims or else gamees made by companies that don't exist no more... anyone care to suggest a fighter sim that have modern aircraft in it that is published recently (hense good 3d)?
AMD A64 3200+Venice @2.65GHZ
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For WW2, and in my opinion, the best combat flight sim out there right now, I would recommend...
IL2: Forgotten Battles with the Ace Expansion Pack and Pacific Fighters (which is standalone but also works as an expansion to FB).
Getting everything installed properly can be a bit of a pain, but its an awesome game to play online.. The single player is not bad, but since it is a sim, and emphasizes realism, it can get boring at times (long time flying to target, never seing any enemies, etc). In terms of flight realism, its right on par w/ the best sims out there (microsoft flight sim, x-plane, etc) despite the fact that its a combat sim.
Once you have the original and the two expansions, you can download a program called hyperlobby (google it) and you will find a surprisingly large online community with dedicated servers 24/7 as well as scripted cooperative games and league play.
I would hardly consider battlefield 2 a sim. It's a first person shooter/arcade style game. Vehicles (including the jets and helos) and weapon damage are quite unrealistic. If you don't believe me, fly a jet in BF2 and then try flying the F16 in Falcon 4.0, which very closely models the F16 'experience'. Falcon 4.0 is a great game too btw, but pays even more attention to the nitty gritty (complex engine and avionics management) and the graphics aren't quite as nice.