The key to a successful install of the DayZ-Expansion Mod (which brings helicopters to DayZ!) is to make sure you install and get working the CF and Community Online Tools first - otherwise it's very difficult to track mistakes and see where you went wrong.
How To Find Your Steam ID:
Community Online Tools Mod:
DayZ Expansion Mod:
DayZ Expansion Licensed:
Grab your own DAYZ Private Custom Server From Nitrado: (Partner link, helps support this channel.)