Question: is a e4 in the navy a nco

Answer: Yes, In the Army, Air Force, and Marine Corps, all ranks of sergeant are termed NCOs, as are corporals in the Army and Marine Corps. A Marine Corps lance corporal (E-3) is not an NCO, but rather junior enlisted. The rank of corporal (E-4) in the Army is a junior NCO, and is to be shown the same respect as any other NCO. In the United States Air Force, E-5 (staff sergeant) and E-6 (technical sergeant) are classified under the NCO tier, while E-7 (master sergeant), E-8 (senior master sergeant), and E-9 (chief master sergeant) are considered senior non-commissioned officers (SNCOs). In the Navy and Coast Guard, all ranks of petty officer are so designated. Junior NCOs (E-4 through E-6 grade), or simply ``NCOs'' (E-4 and E-5 only) in Marine Corps usage, and function as first-tier supervisors and technical leaders.