Figure out what percentage of the plane, and for that matter just the fuselage, the cockpit is. Then figure out what percentage of that the pilot occupies. Then take into account the armor etc. in and around the cockpit, including the glass in the front which is often "armored". Also, look at the difference between pilot wound percentages now in AH II, especially considering the increase in difficulty of gunnery, and what it was in AH I.
I'm just thinking I'm seeing WAY too many pilot wounds now compared to what it was before, especially considering how much harder gunnery is for most.