The Boeing T-43 is a retired modified Boeing 737-200 that was used by the United States Air Force for training navigators, now known as USAF combat systems officers, from 1973 to 2010. Informally referred to as the Gator and "Flying Classroom", nineteen of these aircraft were delivered to the Air Training Command (ATC) at Mather Air Force Base, California during 1973 and 1974. Two additional aircraft were delivered to the Colorado Air National Guard at Buckley Air National Guard Base and Peterson Air Force Base, Colorado, in direct support of cadet air navigation training at the nearby U.S. Air Force Academy. Two T-43s were later converted to CT-43As in the early 1990s and transferred to Air Mobility Command (AMC) and United States Air Forces in Europe (USAFE), respectively, as executive transports. A third aircraft was also transferred to Air Force Materiel Command (AFMC) for use as the "Rat 55" radar test bed aircraft and was redesignated as an NT-43A. The T-43A was retired by the Air Education and Training Command (AETC) in 2010 after 37 years of service.

The Boeing 737 is an American narrow-body airliner produced by Boeing at its Renton factory in Washington. Developed to supplement the Boeing 727 on short and thin routes, the twinjet retained the 707 fuselage width and six abreast seating but with two underwing turbofans instead of four. Envisioned in 1964, the initial 737-100 made its first flight in April 1967 and entered service in February 1968 with Lufthansa. The lengthened 737-200 entered service in April 1968, and evolved through four generations, offering several variants for 85 to 215 passengers.