Boeing KC‑97 Stratofreighter, a strategic tanker and transport used by the U.S. Air Force from 1951 to 1978. Derived from the B‑29 bomber, the KC‑97 featured a distinctive double‑deck fuselage and served primarily as an aerial refueling platform equipped with a “flying boom” system. Some variants were upgraded with two jet engines mounted on the outer wings to improve performance, making the Stratofreighter one of the rare aircraft to combine both piston and jet propulsion.














