Marine Corps · SSN history

631 Intelligence NCO

Appendix B lists SSN 631 as “Intelligence NCO” in the earlier 1942 and June 1944 references and as “Intelligence Clerk, Aviation” in June 1945, restricted to aviation. For ground forces it directs readers to SSN 636, but this is not an automatic conversion.

Codes named in this history

Codes without a directory match

  • 636 stated by the source. No directory or archive record matches.

Documented history

Intelligence NCO

June 1945 is the manual’s publication date; no effective date is given for this classification change.

  • Any suggested reassignment required review of the individual’s qualifications against the job specifications; SSN 636 was not a universal replacement for 631.
Source extraction notes

Predecessor title from the June 1944 tentative-manual column: Intelligence NCO. Suggested conversions/remarks: Aviation only; for ground forces see 636. The table gives no row-level effective date. June 1945 is the manual publication date, not an effective conversion date.

Source documents (1)

Reviewed September 24, 2026 against references 3 and 4.

Historical information is drawn from the sources linked above. Classification dates are not personal service dates. Spot an error? Let us know.