2016-11-12 11:35:44.612 - Thread: 1 -> Exception occured: System.NullReferenceException: Object reference not set to an instance of an object.
at Sandbox.Game.Weapons.MyLargeTurretBase.IsTargetVisible(MyEntity target, Vector3D predictedPos)
at Sandbox.Game.Weapons.MyLargeTurretBase.CheckNearTargets()
at Sandbox.Game.Weapons.MyLargeTurretBase.UpdateAfterSimulation10()
at Sandbox.Game.Entities.MyEntities.UpdateAfterSimulation()
at Sandbox.Game.World.MySector.UpdateAfterSimulation()
at Sandbox.Game.World.MySession.UpdateComponents()
at Sandbox.Game.World.MySession.Update(MyTimeSpan updateTime)
at Sandbox.MySandboxGame.Update()
at Sandbox.Engine.Platform.Game.UpdateInternal()
at Sandbox.Engine.Platform.Game.RunSingleFrame()
at Sandbox.Engine.Platform.FixedLoop.<>c__DisplayClass1.<Run>b__0()
at Sandbox.Engine.Platform.GenericLoop.Run(VoidAction tickCallback)
at Sandbox.Engine.Platform.Game.RunLoop()
at Sandbox.MySandboxGame.Run(Boolean customRenderLoop, Action disposeSplashScreen)
at SpaceEngineers.MyProgram.Main(String[] args)

This is the error i get after i rebuild a damaged turret (which was damaged in the previous dev build and rebuilding it then had no issue)
Manual or using the nanite factory mod both let the game crash with this exact error.

My world is a survivel planet world might be usefull.