The C-97 was the Army Air Forces (AAF) cargo/transport version of the B-29. Between 1943 and 1950, 74 Stratofreighters were ordered; the first flight occurred on 15 November 1944. A tanker version (KC-97) was introduced in 1950 using the "flying boom" refueling system, and all subsequent USAF contracts for C-97s were for tankers. In all, 890 aircraft were ordered, 74 C-97s and 816 KC-97s. After 1956 USAF KC-97s were gradually replaced by KC-135 jet tankers, but some were modified for continued use in other roles. In 1964, selected aircraft were returned to a tanker configuration (KC-97L) primarily for the Air National Guard. Two jet engines were added to increase speed and altitude, making the tankers more compatible with high performance jet aircraft. Although the last USAF C/KC-97 was retired in 1973, examples remained in use with the AF Reserve and ANG as tankers or air-sea search and rescue aircraft for several years before the last one was retired. During the 1950s and 1960s, KC-97 tankers were stationed at Robins AFB with the 19th Bombardment Wing in support of the B-52 bombers assigned to the Wing. The Museum's KC-97L was delivered to the USAF in January 1956 and served with various units all over the world before being retired in 1977. The aircraft was sold to a commercial user and was acquired through an exchange and flown to the Museum in 1986. Full serial 53-0298. c/n 17080. On display at the Warner Robins Museum of Aviation. Georgia, USA. 18-4-2013