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U.S. Air Force Airman 1st Class Jeffrey Wilson, 723d Aircraft Maintenance Squadron aerospace propulsion journeyman, loosens bolts in a T56 engine used on C-130 aircraft at Moody Air Force Base, Ga., Feb. 19, 2014. Aerospace propulsion Airmen diagnose engine problems, replace defective components and test run repaired engines. (U.S. Air Force photo by Airman 1st Class Ryan Callaghan/Released)