nitro rc cars and trucks are one thing...
these helicopters and planes are pretty crazy, they require insurance in order to fly them...those propellors mated to motors which can range from 12k-40+ rpm motors aint a joke
I saw a tv show one time with RC helis and planes doing stunts. Some wicked stuff there, but that was just insane. I cant even fly my RC plane without causing serious damage 20 seconds after take off. LOL