I can't get through the tank mission where you have to protect them I get..

After the helo drops off the three men kill them from the roof top then shot at the tank on the hill with the grenade launcher on the roof top. You should be able to take the tank out in three to four shots. Then jump off the roof and go up the hill by the next tank that appears and take that one out with the grenade launcher also. Two more helos will show up and then take them out with the machineguns that are mounted on the sand bags on the hill. If you run out of bullets use your grenade launcher to take them out.

P.S. Make sure to go back to restore your health and ammo before the other two hello�s show up so you have plenty of grenades to shot down the helos.

This was awesome I had defeated this thing in under 45 minutes with this glitch,
It's the part where you have to rearmour 2 tank's, then when you're on there is a glitch behind the right gate door squat right behind the door then move right, you should see you'reself move through the door I tried this glitch and it worked, then when you're through go around but don't touch the black area or you are dead, now go around and take the guards down first(your team mate will say he's scared cause he's all alone and he can't come through the door so go kill everyone then go back and plant the bombs on the gate and(note:do the second gate first or you'll be ambushed by the tanks on the hill)(but stay on the hill don't get in it's way or it will fire at you, now use bombs it will help to do it on quick mission so you have extra granades and get an rpg to launch at the helicopter's)now then go back to the first barracade then destroy it then do same thing to get behind the wall and to get near the riendavous check point where you reamour the tanks the enemy armour will appear out of nowhere to fire upon the group use the gun/granade luancher to take it out same with the truck. Now when the helicopters come wait for them to stop then fire just a few inches above them to hit it since the rpg's bullet goes down before it fires. Then after you destroyed the helicopters go back to the gate then go out and then go to the tanks to lead them where they need to go. P.S.:if you want add me(smiter45)if you want more on this and other cheats/glitches