Vehicles can have a config property that lets their crew use GPS, even if the unit does not have a GPS item. This functionality cannot be turned off, which makes it impossible to force players to do land nav, or to simulate GPS jamming, while using these types of vehicles.

Solution: a command to turn this off for a given vehicle. For bonus points, a command to add built-in GPS to a vehicle that doesn't have it in config, but this is not as important.

Suggested syntax:

_vehicle disableGPSEquipment <BOOL>