I did work with UAVs and from what I understand, there are two very different requirements. The "system" as a whole has to work, irrespective of how the object is controlled.
That means for a plane, it has to be flight worthy, following all the aerodynamic principles, only then you can control it; either with an on board controller or remotely.
For a car, the demand is much lesser, and control is simpler.
Am I reading you correctly? Do you want to learn how to control these things remotely? Or build it completely from scratch?
It would also help to know what background you have with electronics, that would enable us to suggest accordingly.
EDIT: Or do you want to learn how to make RF devices, as in the radios, stack (firmware), antenna considerations which would be used to control planes and cars? I would call this learning how to make RF data modems.