LTC Demirjian is a native of San Diego, CA and entered the Army in June 1989. Following basic training at Fort Jackson, SC, LTC Demirjian attended Warrant Officer Candidate School and Initial Entry Rotary Wing Training at Fort Rucker, AL.

His first assignment after flight school was in 2nd Squadron, 7th Cavalry, 4th Infantry Division, Fort Carson, CO, where he served as an AH-1 Pilot and OH-58 Unit Trainer. LTC Demirjian was then assigned to 4th Battalion, 501st Aviation Regiment, Camp Page, Korea where he served as an AH-1 Unit Trainer. LTC Demirjian then attended Officer Candidate School, the Aviation Officer Basic Course and OH-58D Aircraft Qualification course and was assigned to 3d Squadron, 4th Cavalry, 3rd Infantry Division, later reflagged as 1st Squadron, 4th Cavalry, 1st Infantry Division. During this time he deployed to Bosnia as part of IFOR and served as a line and Support Platoon Leader, then Troop Executive Officer. Following the Aviation Advanced Course, LTC Demirjian served as the Regimental Planner for 2d Armored Cavalry Regiment (L), Fort Polk, LA and then as the Commander for Palehorse Troop and Stetson Troop in 4th Squadron, 2d ACR. Following his troop command time, LTC Demirjian was selected for a Joint Staff and Army Staff internship where he served as a Political-Military Planner in the J-5 and as a Special Assistant to the Army Chief of Staff in Washington, DC. LTC Demirjian was then assigned to the National Training Center after which he attended the Army Command and General Staff College. Following CGSC, LTC Demirjian was assigned to the 82d Combat Aviation Brigade, Fort Bragg, NC, as the Brigade Intelligence Officer. LTC Demirjian was then assigned to 1st Squadron, 17th Cavalry as the Squadron Executive Officer and Operations Officer. While at Fort Bragg, LTC Demirjian twice deployed to Afghanistan. LTC Demirjian's most recent assignment was as the 82d Airborne Division Assistant G3 for Training and Airborne operations.

His awards and decorations include the Bronze Star, Meritorious Service Medal, Joint Service Commendation Medal among other awards and decorations. He has earned the Combat Action Badge, the Master Aviator Badge, the Parachutist Badge, and the Air Assault Badge.

LTC Demirjian and his wife of 19 years, the former Courtney Vail, are the proud parents of two daughters, Hannah (14) and Kendall (10).