I give up; I get to the final area where the guns are and get slaughtered. Tried going one firection - killed. Went backalley and then in circle around guns behind all building. Anyone got a winning strategy to shoot down the copter?

OK - finally got it - spend all your time picking off rebels - probably 10-12 total. Once you've cleaned out the alley you came in (3-4 more will come down there later) and 2-3 at the front and 2-4 down the far left side, you can gamble on running to a 50 cal, shooting the chopper until he "locks on" you and then running right at him and then for cover. repeat until he's down

On Ghost Recon: Advanced Warfighter PS2
I am at a station where 2 tanks are rearming in a building,I kill several rebels on the ground and from a helo. But 2 tanks on a hill(to the right) keep hammering the building where my tanks are rearming. a friendly helo is on top of the building but can't get it to do anything. my teammate kills one tank on the hill but the other ones keeps firing till it destroys the build with my tanks...
I am stuck.
thanks...
montana