Marine Corps · SSN history

9950 Amphibian Tractor Crew Chief

Appendix B lists SSN 9950, Amphibian Tractor Crew Chief, under AR 615-26 of September 1942 and its supplements, and suggests SSNs 994 or 997 as possible replacements. These were not automatic conversions: each Marine’s Qualification Card had to be reviewed against the job specifications to determine the appropriate classification.

Codes named in this history

Codes without a directory match

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

Documented history

Amphibian Tractor Crew Chief

June 1945 is the manual’s publication date, not an effective conversion date. No effective date is given for this entry.

  • The June 1945 Present Title column is blank; the entry does not establish a fixed split into both suggested specialties.
Source extraction notes

Predecessor title from the AR 615-26 column: Amphibian Tractor Crew Chief. Suggested conversions/remarks: 994, 997. 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.