One thing that is missing from the vast majority of AI representations is a sense of the "larger picture". To take Il-2 as an example, no matter how well the AI knows how and when to pull a split-s or how to keep it's speed up in a fight, a lone AI fighter will chase down and attack any enemy that it sees, no matter how badly the odds are stacked against it. As it is, the AI's main goal is just to fight, instead of to fight and live. In most situations, and Il2 dogfight will go on until all but one or two of one side get's shot down, and the only time the AI breaks off the fight is when they're damaged or out of ammo. IRL, loosing a third of your side in a fight was a devastating loss, yet it happens with certainty each time groups of AI fight. The only exception happens when the mission uses high-speed aircraft like jets, when the various aircraft get separated and the AI's poor shooting leaves a number alive at the end. The AI never sees that it is the only friendly fighter in the air, surrounded by enemy aircraft, says "Oh sh!t" and dives for the deck as fast as it can and goes home, which frequently happened. The AI recognizes some aircraft as energy-fighters, and does dive as a combat tactic, but instead of extending away to RTB or to climb safely and get energy back, the AI simply pulls out at the bottom and zoom climbs up, leaving it even more vulnerable than if it had stayed up. If the AI is a fighter bomber, it will only jettison it's weapons if it is directly shot at, and never anticipates it by jettisoning and turning to fight before the merge. If these AI FB's are escorted and don't need to jettison, they keep trundling along at cruise speed rather than speeding up and making themselves difficult targets.
I realize this is immensely difficult to code, but it is something to think about. The only sim I have seen that does this convincingly is Battle of Britain II, which uses a system that tracks how much of a disadvantage the AI finds itself in (i.e. friendly:enemy ratio and losses), and at a randomized tipping point makes the loosing side try it's best to get the hell out of dodge. It also uses an AI field-of-view routine so you can bounce an enemy from behind or below, and also let's the AI sometimes loose track of the player if he hugs the deck, just as the human player can loose track of the AI. Often, a dogfight was described by pilots as intense and then suddenly they're alone in the sky. This is doesn't happen too much in Il2, and the AI knows exactly where anything within a fixed radius is and then proceeds to fight to the death.
Of course, if the fight happens at a very small scale, like 2v2 or 4v4, the percentage losses might be expected to be higher, and there are many variations and exceptions. While the AI in Il-2 is better than most, and cert's AI mod was a quantum leap, as is the version in DBW, it would be absolutely fantastic if it were possible to implement a desire to return successfully to base. I'm just trying to point out issues that the outstanding modders here might be able to address.
thanks