The 183rd AS is the group's flying unit and has operated the C-141B since mid-1986. The 183rd TRS was formed at Hawkins Field, Jackson in July 1953 with RB-26Cs. The unit was redesignated 183rd Aeromedical Transport Squadron in November 1957 with C-119Fs, which were replaced by C-121Cs in mid-1961. The 183rd became an Air Transport Squadron and moved to Thompson Field in January 1963, with the 172nd ATG assigned in 1964. Designation changed to the 183rd MAS in January 1966, with the C-124C assigned in February 1967. The unit converted to the C-130E in May 1972 as the 183rd TAS, upgrading to the C-130H in 1980. The unit reverted to a Military Airlift Squadron when it re-equipped with the C-141B.