Special Duty Identifiers (SDIs) are jobs that Air Force officers perform temporarily outside of their normal jobs. Examples of SDIs include: Career Assistance Advisor (8A100) Enlisted Aide (8A200) Military Training Instructor (8B000) Military Training Leader (8B100) Academic Military Training NCO (8B200) Airman & Family Readiness Center RNCO (8C000) Linguist Debriefer (8D000) Research Analysis and Lessons Learned (8E000) Other SDIs include: Commander, Cadet Squadron, USAFA (80C0) Training Commander, OTS (81C0) Instructor (81T0) Academic Program Manager (82A0) An Air Force Specialty Code (AFSC) is an alphanumeric code that identifies a specific job. Officer AFSCs have four characters and enlisted AFSCs have five characters.