The depth charges are easily turned off. Go into the AI folder, and find the "AIchasedef.ini" file. Turn off read only in its properties, then open it up in a text editor. Scroll down to the helicopter properties, and find this line "helicopterProjectileDropHeight" change the number after it to 1.0. Save, close, adn reapply the read only property. The helocopter will no longer drop those stupid flaming barrels.
Thanks to Greyryder.