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Marine Corps · SSN history

628 Senior Technical Instructor

Appendix B identifies SSN 628 as “Senior Technical Instructor” under AR 615-26 of September 1942 and its supplements, leaves the June 1945 title blank, and refers to Chapter I, Section 7. That section generally groups instructors with the specialty they teach, but the entry does not establish a cancellation, rename, or fixed replacement for SSN 628.

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Documented history

Senior Technical Instructor

June 1945 is the manual’s publication date. No effective date for a change to SSN 628 is given.

  • Classification depended on the individual’s qualifications and the applicable job specification; distinct instructor specialties existed where there was no tactical or operational counterpart.
  • SSN 659, Instructor (Designated Subject), applied only to rare enlisted instruction without a closely related military job or a specific instructor specialty, not automatically to former holders of SSN 628.
Source extraction notes

Predecessor title from the AR 615-26 column: Senior Technical Instructor. Suggested conversions/remarks, as printed: See Section 7 of Chapter I. This is a cross-reference or instruction to review the job specification, not an explicit fixed replacement or proof of cancellation. The table gives no row-level calendar effective date. June 1945 is the manual publication date, not an inferred individual conversion date.

Source documents (1)

Reviewed September 24, 2026 against references 3, 4 and 5.

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