Shaw Air Force Base is a United States Air Force base located approximately west-northwest of downtown Sumter, South Carolina. It is under the jurisdiction of the United States Air Force Air Combat Command . The United States Air Force 20th Fighter Wing is the host unit.It is one of the largest military bases operated by the United States, and is one of only two air bases in CONUS with an active railroad line. The Shaw line was constructed in 1941 to bring in materials for base development, and has two GE 80-ton locomotives, 1644 and 1671.