Airman 1st Class Christopher Thomas, 28th Maintenance Squadron aerospace propulsion apprentice, inspects and cleans second stage engine blades from a General Electric F101-GE-102 turbofan engine at the propulsion flight building on Ellsworth Air Force Base, S.D., Nov. 29, 2011. During the inspection, the mechanics have to check 88 blades, which allow the engine to produce more than 30,000 pounds of thrust. (U.S. Air Force photo by Airman 1st Class Zachary Hada/Released)