These are also used by film studios for props involving planes that are no longer available, as well as to save costs on hiring the real thing. The cost of hiring a helicopter for a week is substantially less then hiring a remote controlled scale model one. Model aircraft are used to take low level Arial photography, this is especially useful in built up areas where normal aircraft can’t fly. For this purpose model aircraft are modified or specially designed.
Airlines and manufactures use them for marketing, as well as for testing a prototype.