If I recall correctly, there are guys with bazookas on the first heli base, that should do the trick for the first ones. After that, I just used the long arm thingy to grab the helis from a distance as they were really close.
Instead of running up the road to get to the first one run along the buildings on your right, you can get to the heli before it takes off. Then, you can just hijack it and use it to take out the other ones. Its pretty easy if you stay high enough to avoid the turrets and the rocket launcher guys.
[Edited by hegemon875, 6/16/2009 7:22:32 AM]
[Edited by hegemon875, 6/16/2009 7:22:50 AM]
-Select Whipfist as weapon
-Charge jump, and jump to one of the sides to avoid the lasers or rocks.
-Charge your Whipfist (right click) while jumping
-This makes an impress on her.
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