The Boeing Model 367 Stratofreighter was an American in-flight refuelling tanker and transport aircraft developed during the Second World War as a transport version of the Boeing B-29 bomber. The Boeing Model 367 Stratofreighter entered service with the military in 1949 and was withdrawn in 1977 after several variations had been produced, the C-97, HC-97 and KC-97 families. The KC-97G variant was a dual in-flight refuelling tanker and transport and was powered by four Pratt and Whitney R-4360-59B radial piston engines providing a top speed of 603 kmh and a range of 6920 km. The KC-97G carried a flight crew of five and up to 96 troops or 69 litters in the cabin in addition to two external fuel tanks. Research Boeing Model 367 Stratofreighter