Some basic prerequisites to killing enemy air defenses.
-No MiG-29s or Su-25s airborne.
-Preferably 2 F-16s so if you get jumped by a MiG you have a chance.
-Probably a joystick.
-A slightly intelligent wingman.
-Full ammo.
Ok so you're A-10 is as usual dead and you've just killed that last base-raping MiG-29. You keep getting painted over south village and a rather confused blackhawk just vanished from you radar. Theres a SAM who thinks he's real cool down there somewhere. Now before you go and try to do something stupid, think for a second:
-Where is the SAM site?
-What kind is it?
-How much/ what type of ammo do I have?
-What is the best ingress/egress?
If you're an intelligent pilot you'll probably try to stay near a friendly plane for several reasons.
1. Share countermeasure cover. You can have almost 30 seconds of cover provided you follow your flares downwards.
2. Can cover a wider angle of space.
3. Can concentrate your fire easily on a target.
4. Can make targeting a little harder for a gunner.
You don't have air to ground weapons, and assuming the enemy isn't completely inept, they will move their SAMs into position when your A-10 is dead. Missiles aren't done yet so right now you will need to learn to aim your gun and keep it on target.
There are a few ways to make life very easy for yourself when engaging an mobile SAM.
1. Toss and follow your countermeasures. Your flares are dispensed from below your fuselage. A quick roll will cause them to scatter, making it more difficult or impossible for them to "edge out" (put your plane on the edge of their scopes to keep the flares out of the picture) your signature. Another good idea is to attack from high angle and "follow" your counter measures in. He may never even get a lock on you.
2. Use terrain to full advantage. Have your wingman attack from the top while you hit it from behind in rapid succession. If he sees you coming use a "double tap" jinking shot to cause him to throw off his aim. DON'T POP FLARES WHEN GOING INTO TERRAIN! *ahem*. It will just waste them. After he loses lock you will hear the tone for about 1/2 to 1/4 of a second. Don't panic and delay your next attack by wasting flares.
3. Don't fly right towards it for more than about two seconds. This allows you to engage with guns while he is still leading you. First let out about 20-30 rounds into him. Then Turn 90 degrees away from him for a second or two. Then go into a hard turn into him and let out another 20-30 rounds.
*Remember: Theres a 1/3 second delay for arming the M61 so factor that in during an attack. Keep your gun time to about 2 seconds (about how long till he lines up properly).
4. Take advantage of your wingman and use him, or yourself as live bait for the SAM. Flare him from about 150m and wait for the flares to fall into his vision (you're much faster then the flares so you can give them a head start). You will most likely not have a tone right now. Just fly towards cover and as you egress, have your wingman come in with sidewinders and light up the SAM from behind. He will still have flares and will have an easy get away.

Tunguska-M1: Takes 250 rounds to put down, or 8 direct hits with a sidewinder. Missiles work best in a large salvo because you can adjust your aim, rather than making an educated guess with a single shot. You can land 60 rounds per pass max. So with a wingman you will need to each make 2-3 passes.
How you will die:
1. Flying directly at it. He won't have to lead you at all. So attack in a turn and use terrain to come from an unexpected angle.
2. Crashing into terrain. I can't help you with this other than saying to recage your eyes depth of field by looking away form your screen for a few seconds.
3. Not evading hard enough. When you are getting shot at break as hard as possible. You have a turn rate 2x as fast as the missiles. So just break as hard as possible and you'll be fine.
4. Not watching your egress and getting jumped by a MiG. Just press C and pay attention to where you're going. Don't stop turning either.
I could go on for much longer, but this should make life much easier and allow you affect the ground battle significantly. Happy hunting.

