RE: Nav chart question
I just looked thru my Chapmans, but no qualitative definintion of PA. But if I remember my classes correctly, it means there is not enough independently verified data to chart the exact location. However, there is enough observations to verify the existence of said structure/hazrd/obstruction in the area.
Also worth noting is the less frequently seen PD (Position Doubtful) and ED (Existence Doubtful), meaning the reported observation could not be subsequently verified.