Convair XC-99

The Convair XC‑99, built by Convair in 1947, was the largest all‑metal transport aircraft ever constructed in the United States. Developed from the B‑36 bomber program, the XC‑99 shared the bomber’s six‑engine, low‑wing layout but featured a massive, box‑shaped fuselage that could accommodate up to 100 fully equipped troops or 125,000 pounds of cargo. Its eight Pratt & Whitney R-4360 Wasp Major radial engines generated 3,500 horsepower each, giving the aircraft a top speed of 375 mph and a range of roughly 4,000 miles with a full payload. Only a single prototype, serial number 44‑70271, was built; it entered service with the United States Air Force in 1949 as a strategic air‑lift test bed. During its operational life the XC‑99 demonstrated rapid loading and unloading techniques, reinforced the concept of high‑capacity strategic transport, and set several world records for payload and distance. Although the program was cancelled due to evolving jet technology and high operating costs, the XC‑99’s design influenced later heavy transports such as the C‑124 Globemaster and paved the way for modern strategic airlifters. The aircraft remains an iconic symbol of post‑war American engineering ambition.

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