[Commander G]

Suicide Junkie is right, if you have a pure PDC ship, it will not approach planets or satellites. Put on the cheapest, lightest weapon you have that can target satellites (Depleted Uranium Cannon I).

I had a similar thing happen to me a while back when I converted on obsolete escort hull into a point defense ship. It was worthless until I put a direct fire weapon on it. No matter what you do with the combat orders, a pure Point Defense ship will not engage. It also will not stay in formation.