Airmen assigned to the 773d Civil Engineer Squadron practice assembly and cleaning of M4 carbines during Prime Base Engineer Emergency Force Day on Joint Base Elmendorf-Richardson, Alaska, Sept. 24, 2021. Prime BEEF Day is a monthly training day hosted to allow 773d CES Airmen to hone their skills and stay up-to-date on necessary training courses. (U.S. Air Force photo by Airman 1st Class Patrick Sullivan)