I noticed that too. They break as soon as I press the trigger.
Also, yesterday I was flying a 109 E4 against Defiants, and I was seriously outpaced by them. There's not much CEM to do in the 109 with its automatic pp, so I don't know why full throttle wasn't enough...
It seems that the AI doesn't even use the FM of the actual plane. They always climb away, or run away, never lose E, etc...if you still get behind them tehy start rolling and rolling and rolling, in a screaming dive of 400 mph, your plane barely moves and the metal squeaks, but the AI still rolls like an F16.
So:
1) give the AI the same FM a human would use, and don't let them manage their plane perfectly either.
2) restrict their visibility and reflexes. (like in BoB2 WoV)
3) make them act human, i.e. more variety of maneuvers, trying to use their plane's strenghts, not only barrel rolls and occasional scissors. (like in BoB2 WoV)