On page 131 of the FC3 Flight Manual, under the Air-to-Air Weapons Delivery mode section of the A-10A HUD and TV Monitor Ops chapter, it mentions pressing the 2 or 3 key to activate this GAU-8A or AIM 9-Ms. However, when I access config and look at my control options for the A-10A, keys 2 and 3 aren't even options, just 1, 6 and 7. I believe I did manage to select a Sidewinder at 1 point, but can't remember how, might have been 6 + D, but I'm not sure; missile just thudded into the tree tops anyways.
So far I've only been messing around in the A-10A CAS insta action, but I'd love to fire some Sidewinders on those Gunships
So I'm wondering how you use AIM-9Ms with the A-10A, or if it's even possible?