LtCol Sean P. Crilley enlisted in the United States Marine Corps in November 1996, attended recruit training at Marine Corps Recruit Depot, Parris Island, SC, and Marine Combat Training at Camp Geiger, NC. In May 1997, he began Aviation Operations Specialist School at Marine Aviation Training Support Squadron 1 in Meridian, MS.
Upon graduating, he reported to Marine Fighter Attack Training Squadron 101 at Marine Corps Air Station El Toro, CA. In July 1997, he began serving as Flight Planning clerk at Headquarters and Headquarters Squadron, Marine Corps Air Station Miramar, CA. In November of 2000, he ended his active service and pursued a college degree.
In 2006, he graduated from George Mason University with a bachelor’s degree in Sports Management. In July 2009, he was selected for Officer Candidate Course and attended Officer Candidates School that October. He was commissioned as a Second Lieutenant in December 2009 and directly reported to The Basic School, Quantico, VA, where he received his number one choice in Primary Military Occupational Specialty, Aviation Supply. In August 2010, he reported to Naval Supply Corps School in Newport, RI for the Basic Qualification Course (BQC) in Aviation Supply.
Upon completion of Aviation Supply Officer School, he reported for duty at Marine Aviation Logistics Squadron 29, New River, NC, where he served as the officer in charge of the Consumables Management Division, Squadron Support Division, Continuous Process Improvement and Assistant Operations Officer of Marine Aviation Logistics Squadron 29. In January 2014, First Lieutenant Crilley deployed to Helmand Province in support of Operation Enduring Freedom with Marine Aviation Logistics Squadron 40 and served as the Supply Management Division and Assistant Aviation Supply Officer.
In August 2014, he returned to the Marine Aviation Logistics Squadron 29, where he worked as the officer in charge of the Supply Response Division and Marine Aircraft Group 29, Naval Aviation Enterprise, Current Readiness Officer. In May 2014, he attended resident Expeditionary Warfare School at Marine Corps Base Quantico, VA.
In May 2015, Captain Crilley received PCS orders to Defense Logistics Agency, Richmond, VA. He served as the H-53 and T-64 engine Weapons Systems Program Manager. He received a follow-on assignment to the Aviation Logistics Department of 1st Marine Aircraft Wing in Okinawa, Japan to serve as the Aviation Supply Officer. In June 2019, Captain Crilley executed orders to Marine Aviation Logistics Squadron 36 aboard Marine Corps Air Station, Futenma, Japan, where served as the Aviation Supply Officer until May of 2021 and was promoted to Major in October of 2019. In 2021, he was selected for the Commandant of the Marine fellowship at FedEx Express, where he was awarded the FY22 Legacy Key Award.
In 2022, Major Crilley received PCS orders to Headquarters, Marine Corps Department of Aviation, Aviation Sustainment Branch (ASB) where he served as the Aviation Supply Officer. During his ASB tour, he served as Aide de Camp for the Deputy Commandant for Marine Corps Aviation and promoted to his present rank in October 2025.
Lieutenant Colonel Crilley assumed command of the Center for Naval Aviation Technical Training Unit, Cherry Point, NC, in June 2026.
His personal awards include the Defense Meritorious Service Medal, Meritorious Service Medal, Navy and Marine Corps Commendation Medal, Joint Service Achievement Medal, Navy and Marine Corps Achievement Medal (Gold Star in lieu of Third Award), Good Conduct Medal and the Military Outstanding Volunteer Service Medal.