Hit bubble...The AW hit bubble was a bubble that went from nose to tail and wingtip to wingtip. Hit the bubble and you got a hit on the plane. Each plane had a pre-determined amount of damage it could take. When the damage points were gone, the plane blew up. In AW, the bubble had little impact on headons. AH's method is miles ahead.
Headons in AW...Headons in AW were handled with a randomizer. Each headon hit was randomly checked to see if it was a hit, the randomizer was set at 10% (1 hit registered out of 10 hits made). After BB took over, planes with centerline guns (109s and 38s) were given a 'bonus' to the randomizer. This made headons from them extra lethal.
Headons in AH...The gunnery in AH is attempting to be a 'reality' based model. That, in large part, is what makes it so much better than the model in AW (Dok..remember the 'laser' gunnery in AW

). The reason that headons are so lethal in AH is the unrealistic way in which players use the model. Think about it, in the real world, how many people would want to play chicken in a airplane with closure rates of 700 to 800 mph?
I can tell you what Dale would say (because I've asked him

), the gunnery is realistically modeled...it's not his fault if players insist on using it in an unrealistic manner.
With all of the 'new' guys trying out the K4's, I have seen more headons that ever, lately. While I understand the difficulty in learning to deflection shoot in a 109, it find it sad that so many don't bother to try to learn.