My DS did this to his sister when they were pre school age. Not a radio controlled car, but one of those vroom vroom ones, you know, that you have to 'wind up' several times and then let go and it scoots across the floor. Only he vroom vroomed it and tried to let it go on her head
. By the time I got to her, alerted by her screams, the wheels were still spinning and getting ever tighter to her scalp. No choice but to cut it. She had a bald patch the size of an old penny
(And DS had his car confiscated
)