This photo set contains general photographs of T-28D & AT-28D aircraft. The T-28D, was a counter-insurgency (COIN) version of the T-28 that was developed to provide a close-air support aircraft to air forces of nations with limited economic resources. Surplus T-28As were converted to T-28Ds by replacing the Wright R-1300-7 engine with a much more powerful Wright Cyclone R-1820-56S engine and a three-blade propeller. This required changing the cowling to the larger design as used on the T-28B. The wings were strengthened, and hardpoints to carry a variety of external stores were added. Initially, machine gun pods could be carried, but the T-28D-5 variant had ammunition boxes mounted inside the wings. 500 rounds of ammunition could be carried in each wing to supply the .50-caliber machine gun mounted under the wing in a faring. Additionally, the landing gear was strengthened to handle the higher operating weight of the aircraft. While North American converted most T-28Ds, seventy-two were modified by Fairchild Aircraft and designated AT-28Ds. Some, if not all, of these were equipped with ejection seats specifically designed for the aircraft. Some T-28Bs and even a few T-28Cs were also converted to T-28Ds.
T-28Ds were used between 1961 and 1964 in Vietnam and were flown by the South Vietnamese Air Force (VNAF). Several other nations operated T-28Ds as well, including Bolivia, Republic of the Congo, Ethiopia, Laos, Nicaragua, and Thailand.