The USN instituted Warrant Officer aviators for rotary wing and patrol planes (don't know if E-2/C-2 also) a few years ago. So yes, they're there alright, as most of the originals have by now finished their training and are out in the fleet. Unlike Army Warrants, I do believe the USN WO's have to have been an E-6 minimum before qualifying, whereas the Army guys can be off the street.