While in use, the aircraft set international records for cargo carrying at various speeds and altitudes. But jet technology pushed the XC-99 into obsolescence, and the Air Force never ordered another.

The XC-99 was first flown on a sunny day in San Diego in the year 1947, seemingly a good year for mammoth aircraft (the Spruce Goose took its only flight that same year). The XC-99 was a transport ...

The XC-99, which was also a double-decker and powered ... the UK government had fired up its own transport-aircraft ambitions with a multi-pronged strategy that included a large propeller-driven ...