Well, it's for a couple of reasons.
My father was in the Army Air Corps in WW2 (not flight crew, and never left the US), and my uncle was a top gunner on a B 17. He was shot down on his second to last mission. KIA.
So I grew up with WW2 airplane stories, one of my first toys that I remember was a cast metal P 40. I still have my Dad's uniform jacket and bivouac cap.
Couple that with my love of anything that can fly and there you have it.
That's what got me started in the first place.
What keeps me doing it are the friends I've made along the way, and the fun of flying against one another.
Can't wait to have a P40 modeled in this game engine.