I think the color you are referring to is actually Magenta, as used
on real world navigational charts. I think the circles actually refer
to the ribbons (pinkish) on the uniforms of the mechanics that Hitech is adding to the game. In this "don't ask, don't tell politically correct military, I am not going to ask what the ribbons are for as long as the mechanics fix my plane. They will fix your
airplane on the re-arm pad as well as massage your aching shoulders.