Pilots from the 37th Helicopter Squadron at F.E. Warren Air Force Base, Wyo., complete a pre-flight check of a UH-1N Huey helicopter before taking off from Ellsworth Air Force Base, S.D., Dec. 7, 2017 during a training exercise. The exercise provided each of the three units an opportunity to integrate with other Air Force Global Strike Command platforms and improve their strengths and capabilities in the field. (U.S. Air Force photo by Airman 1st Class Donald C. Knechtel)