Nightrider, we did cover this subject in our training and I did pay attention, but it was all THEORY to me... and theories can often be proven wrong, hence my question.
As I didn't have a background in aviation before I became an ATCO, all my knowledge comes from what they told us, so consider me trained from scratch...
But anyway, now I do know, and thank you for filling in the blanks... and that goes to all you guys who replied.
