The headline is wrong.
Apparently the blade struck him in the throat and he probably bled to death.
No remote Control Helicopter could lop off a person’s head.
Well...well that's a horse of a different color.
Read the article:
I was playing at the park and we came into the clearing and we just saw a body on the floor, he was just decapitated, the whole top of his head was gone, said Maria Delgado, 13.
He wrote just last month on his video channel that he was loving his Trex 700N model one of the best nitros that I have ever flown with so much power.
Example (actual RC, not actual victim):
The UK papers are claiming he was decapitated, but the blades could easily have cut his throat, nearly decapitating him.
Not exactly what you were thinking of, but THIS 'remote control helicopter' will slice & dice anyone.
Kamans Unmanned Aerial Systems K-Max UAT