Thanks for posting that Willy....so the answer to Daveroo's question is the "N" means "N", and that's all "N" means.
Just an arbitrary designation. So many things are.
No, not any longer. Today it designates an aircraft as a US registered vessel of the air.
It was arbitrarily assigned for this use, but it is no longer arbitrary as it relates to being on the aircraft. For example, say I purchase an aircraft registered in Canada. I have to apply to the FAA for a new registration number (starting with "N") if I wish to re-register it in the United States. And, if I base it inside the United States, then I have to.
Ken
Now that is interestingly funny, RailrunnerI thought the N stood for "Normal", registered in the US. Interesting.