Airmen from the 28th Maintenance Group conduct a routine maintenance check of a B-1 bomber during an Operational Readiness Exercise at Ellsworth Air Force Base, S.D., Feb. 24, 2012. The exercise tested Ellsworth’s ability to efficiently and effectively mobilize Airmen and assets in response to worldwide contingencies. (U.S. Air Force photo by Airman 1st Class Anania Tekurio/Released)