Everyone loves big planes. The bigger they are the more interesting they become. Famed mammoths like Howard Hughes’ HK-1 “Hercules,” otherwise known as the “Spruce Goose,” and Antanov’s gigantic An-225 “Dream” conger up feelings that man has somehow cheated nature by creating such flying hulks. Even today’s A380, the grand star of any international airport that can receive them, makes people stop in mid traffic just to marvel at it’s imposing form. So what really makes the cut as a gigantic airplane? There is no real criteria, it’s just one of those things that you know when you see it.
Buried deep amongst Aviation’s long line of flying juggernauts is a little known but very remarkable machine that rivals almost anything today in shear size and visual impact, the one of kind Convair XC-99. The XC-99 was first flown in 1947, seemingly a good year for mammoth aircraft (the Spruce Goose took its only flight in that year as well), in San Diego, CA. The XC-99 was a transport derivative of the legendary B-36 Peacemaker strategic bomber, a six piston engine toting pusher prop aluminum beast that became a staple of America’s long-range strategic strike capability for almost a decade. The idea of adapting the B-36 for the intercontinental transport role was fairly intuitive as the Peacemaker had true intercontinental reach and a sizable payload capability to begin with. Curtis utilized key components of the B-36 to produce the XC-99, although the fuselage was designed quite different from the bomber configuration. The XC-99 disposed of the B-36′s long and slender lines and replaced it with a massive double-decker cavernous body. The XC-99 truly looked like the grandfather of the Airbus A380 we know today. In it’s final configuration the aircraft could haul some 400 fully outfitted troops over long distances or over 100,000lbs of cargo.
Although the aircraft was considered literally a large success, the USAF never ordered any production examples. The jet age was right on the horizon and although the XC-99 was highly capable, many in the USAF’s leadership believed that investing further in maintenance intensive and finicky piston powered aircraft as something of a dead-end. Regardless, the XC-99 was put into service for 7 years, mainly as the B-36 fleet’s cargo hack. During the Korean War the lone XC-99 would fly from B-36 depot to depot and base to base full of parts in order to keep the complex Peacemakers flying.
By 1957 the XC-99 was increasingly expensive to maintain and operate and after 55+ million pounds of cargo and 7500 hours of flightime she was retired at Kelly Air Force Base. She remained at Kelly for almost a half century until 2004 when she was disassembled and brought to Wright Patterson AFB for restoration and eventual display. Sadly, she has remained in pieces outside at Wright Patterson for years as the museum has been struggling with how involved the restoration of the now highly corroded aircraft would be. Regardless of her unfortunate state today this XC-99 was one seriously massive piece of hardware, and to think she could fly almost 10,000 miles on piston motors is just astonishing…
An interesting aspect of the XC-99 program was Convair’s almost successful attempt at turning the massive double-decker cargo-ship into a luxury airliner. Resembling the Airbus A380 of today, the Convair Model 37 would have had open living areas, circular staircases and many other luxury features more reminiscent of high-end trains or cruise-liners than an airliner as we know them today. The Model 37 was configured to carry 210 passengers in an all luxury layout over a 4500 mile distance. Continental even went as far as ordering 15 of these super jumbos of yesteryear, but once they came to the realization of just how much fuel and oil those six massive pistons would consume they pulled out of the project stating that it was economically un-marketable and unless the aircraft could be fitted with turboprops, a cutting edge technology at the time, they could not purchase the planes. Unfortunately turboprops never made it to the Model 37 and what would have been the largest airliner of it’s kind never made it off the drawing board.
*Photos via Goleta Air & Space Museum, check them out at: http://www.air-and-space.com/