Well, I haven't run any RC planes yet (hoping to order my first plane by the end of the week), but my friend has a nitro truck without a muffler, and it screams bloody murder, so I started to bring earplugs. Problem with those were, they were full of earwax and I couldn't hear anyone even if they yelled, which could be pretty dangerous. So I used just regular head phones that attach to nothing (the kind that covers your whole ear). It reduces sound by quite a bit, and I can still hear everything I need to