Lt. Gen. Robert D. McMurry Jr., commander of the Air Force Life Cycle Management Center, Wright-Patterson Air Force Base, Ohio, and Matt Joseph, City of Dayton commissioner, unveil the new McCook Field historical marker during the McCook Field Centennial ceremony in Dayton, Ohio, Oct. 6, 2017. McCook Field began in 1917 under the U.S. Army Signal Corps Airplane Engineering Department and was a key part of the research and engineering of aviation. (U.S. Air Force photo by Wesley Farnsworth)