I guess since I'm new, my posts are being mod reviewed if I make a post with a link.
I have two posts in queue with links.
The same argument is developing here which developed between a Microsoft wannabe and me. (which is the reason for this thread explained in a post which is still awaiting mod review from yesterday. The microsoft wannabe wasn't convinced with all the sources I provided for him and wanted a thread at pprune,).
I'll try to attach a diagram from Boeing. Hopefully this will clear it up? (and hopefully it doesn't get put into the mod queue).
Since I can't post links yet, just google "Angle Of Attack" + "Flight Path Vector" + "Pitch".. You'll find the same Boeing document in the first or second hit (along with a long list of other sources including a US Patent from 1971), who explain AOA for an
aircraft is Aircraft pitch relative to FPV.
Also, if you've never flown a Heads Up Display, or if your aircraft doesn't have one (or an AOA indicator), you may still think AOA is defined
only as Wing chord to relative wind. It's not. The aircraft as a whole also has an AOA. It is defined as the difference between Pitch and the Flight Path Vector. The generic definition for AOA as pointed out in the first reply by kijangnim.
ALPHA:Also α, also angle of attack, the angle between the relative wind and the longitudinal axis of the body, x-z plane, deg.