Airman 1st Class Peter Xiong, 28th Aircraft Maintenance Squadron crew chief, inspects a fuel sample from a B-1 bomber at Ellsworth Air Force Base, S.D., Oct. 24, 2013. There are 28 sump ports on each aircraft that must be tested to determine if the fuel contains debris, hydraulic fluid, water or other contaminants. (U.S. Air Force photo by Airman 1st Class Alystria Maurer/Released)