Helicopter Copilot Turret Development Issue

[Brickky 1]

At the moment, I'm trying to reconfigure an airframe for learning in developing vehicle assets, and currently having an issue with the the copilot turret.

cfgVehicles
{
  class Helicopter;
  class Helicopter_Base_X: Helicopter
  {
      class Turrets;
  };
  class Helicopter_Base_Y: Helicopter_Base_X
  {
      class Turrets: Turrets
      {
          class CopilotTurret;
      };
  }; ...

After loading the addon as a local mod, the game launches normally until it hits the 'Initializing Addons' stage of the process, where it will crash with the exit code '0xC0000005 - STATUS_ACCESS_VIOLATION'. 
Anyone know how to resolve it or know where I went wrong here? I already tested it with the turret attributes commented out and confirm that it has something to do with the code above.

 

EDIT: Main goal is to enable co-pilot to use chaingun and aim it through turret camera, so if the above is irrelevant please let me know.