T o d d P a t t i s t wrote:

AOA is a scalar.

Actually, if the wing is reasonably designed, the AOA *is* a vector. It
changes along the wing, usually being smaller at the wing tip and bigger
at the wing root. Hence, it cannot be described by a single scalar, but
rather by a -you guessed it- vector. On the most modern wings (e.g.
Antares), this vector is even infinite-dimensional.

I'm aware that this was not what Neil meant when he was talking of AOA
being a vector.

Stefan