Don't settle behind them, it'll kill you in a furball. Use your speed and fly right past, climb steeply, dive to their deep six and hit them again from slightly below. The AI loves to split-S when being bounced, only this time he'll do right into your sights! If he doesn't split-S, then pull your sights up to him and BAM(meaning shoot, don't ram
You won't probably kill them as fast this way, but your six will stay clear. If it's only a few P.11s and your wingman is covering you then you it's ok to settle, though I'd still recommend the above way of dealing with them.