A 28th Aircraft Maintenance Squadron crew chief speaks with B-1B Lancer aircrew from the 34th Bomb Squadron at Ellsworth Air Force Base, S.D., during a pre-flight maintenance check prior to a Bomber Task Force mission to the U.S. European Command area of responsibility May 10, 2020. BTF missions provide opportunities to work and train with U.S. allies and partners, while strengthening capabilities by familiarizing aircrew with air bases and operations in different parts of the world. (U.S. Air Force photo by Staff Sgt. Hailey Staker)