Crew chiefs from the 155th Air Refueling Wing, perform pre-flight checks of the KC-135 Stratotanker Feb. 4, 2024, National Guard airbase in Lincoln, Nebraska. The Airmen are exercising a large-scale readiness exercise that relies on well-considered planning, expertly trained personnel, and the willingness to respond to the nation’s needs at a moments notice. (U.S. Air National Guard photo by Airman 1st Class Jeremiah Johnson)