flarepilot, thank you for your reply.
I've been interested in aviation ever since we lived in the US for 2 years in the early 90s. My best friend's Dad over there was a First Officer with US Air. He even arranged for my Dad and I to spend a few hours in a 737 sim at Charlotte Douglas. Those were the days!
So in answer to your question, I'm just genuinely interested to know how it all works. What's that for? Why's that done? No axe to grind or ulterior motive.
I have plenty more questions where these came from!
