[NPCs] npc_arbeit_helicopte crashes the game if the player enters a vehicle. [Needed for Aperture Zero]

[danskart]

If a npc_arbeit_helicopter exists in a map and the player enters vehicle entity the game crashes.

Steps to reproduce the behavior:

1. The npc_arbeit_helicopte has to be anywhere in the map
2. The player has to go to a driving state by entering a buggy, jeep, apc, pod, ex.
3. The game crashes

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Ill really love this to be fixed in the foreseeable feature, because I have plants for the player to encounter a Arbeit helicopter in the Ending of Aperture Zero and fight it in a vehicle.