If I throw a grenade at the start of "Helicopters" mission and do any friendly fire with it then hide in any place so they don´t kill me the mission sometimes won´t end because of friendly fire but rather end a while later for not taking off with the helicopter.

Also I can´t get into the helicopter after the grenade explodes. If I throw the grenade under my units and then manage to get in the helicopter before the granade explodes then the mission ends correctly for friendly fire.

Other thing that happens sometimes is that when I hit someone with the grenade at the start of the mission my units will not try to kill me and the units that are already in the helicopter will get out.