Petty officer describes several
enlisted ranks of
non-commissioned officers in the
United States Navy, ranging from
E4 to
E9, though conventionally used for
E4 to
E6.
The rates are as follows:
E4 Petty Officer Third Class
E5 Petty Officer Second Class
E6 Petty Officer First Class
Higher enlisted rankings wear a different uniform altogether, and are generally addressed as "Chief" rather than "Petty Officer".
E7 Chief Petty Officer
E8 Senior Chief Petty Officer
E9 Master Chief Petty Officer