Step 1 - Take out/equip your favorite anti-air weapon (I recommend the Strella)
Step 2 - Look up in the sky when the Enemy Counter Spy Plane is called in
Step 3 - The Counter Spy Plane(s) is/are the ONLY planes that fly counter-clockwise (anti-clockwise for you Brits) around the map.
Step 4 - Once you spot that Counter Spy Plane TAKE IT OUT! You know I will if given the opportunity.
Thank you for your help!