Damn... Having those helis patrol is harder than I expected...
Meanwhile I've also improved the helis crashes : they'll no longer spawn next to the player - meaning that their position will be a bit random, but on the other hand you'll be able to spot them from afar, just like MP.
I think I will update this week and keep the helis patrol thing for later... Right now I only have the combat roll feature to fix plus a few minor things.
I might also add some kinda respawn script for survivor AI's ;)