I am trying to add an arrow pointing to the outside of a polar plot. I need it to indicate an aircraft heading. It needs to be outside the plot area and ideally attached to the plot edge pointing toward the center. It would look like this
Polar plot with arrow outside
I have only been able to get the arrow within the plotted area and have not seen anything in the documentation that would achieve what I am looking to do.

I tried to create two polar scatter plots, one being a zoom-in of the other. I have no problem configuring the font properties of the angular axis, but my attempts to change the fonts of the radial axis have not been successful.