Airman 1st Class Christa Tamez, left, and Airman Wilson Crespo, 362nd Training Squadron A-10 crew chief Airmen, inspect the wings of an A-10 aircraft during one of their classes at Sheppard Air Force Base, Texas, Jan. 5, 2018. Tamez and Crespo are reviewing and practicing for a performance check coming up. The students are tested multiple times during each course and the test could be either a written exam or a practical assessment. (U.S. Air Force photo by Airman 1st Class Pedro Tenorio)