peppering a helicopters fuselage with bullets (even up to 20mm for some helicopters) is not going to cause much damage, you have to go for the vital parts such as the main or anti-torque rotors but considering that this is a simulator and that reality is really hard to mimic then maybe faring at the fuselage actually dose something i don't know
by the way BloonerNL i have found that even though the windows of the Ka-60 are bulletproof the doors and framework is not. i fired a couple of rounds into the door and the pilot was dead, kind of weird that the windows are 100% bullet proof but the doors provide almost no protection.