32°08′55″N110°50′32″W / 32.14870°N 110.84233°W /32.14870; -110.84233
| XC-99 | |
|---|---|
 | |
| General information | |
| Type | Heavy transport |
| National origin | United States |
| Manufacturer | Convair |
| Status | Canceled |
| Primary user | United States Air Force |
| Number built | 1 |
| Serial | 43-52436 |
| Total hours | 7,400 hours |
| History | |
| Introduction date | 26 May 1949 |
| First flight | 24 November 1947[1] |
| Retired | 1957 |
| Developed from | Convair B-36 Peacemaker |
TheConvair XC-99, AF Ser. No.43-52436, is a prototype heavycargo aircraft built byConvair for theUnited States Air Force. It was the largest land-based piston engine transport aircraft ever built, and was developed from theConvair B-36 Peacemaker bomber, sharing the wings and some other structures with it. The first flight was on 24 November 1947 inSan Diego, California, and after testing it was delivered to the Air Force on 26 May 1949.[2] TheConvair Model 37 was a planned civil passenger variant based on the XC-99 but was not built.
Design capacity of the XC-99 was 100,000 lb (45,000 kg) of cargo or 400 fully equipped soldiers on itsdouble cargo decks. A cargo lift was installed for easier loading. The engines face rearward in apusher configuration.
The Convair Model 37 was a large civil passenger design derived from the XC-99 but was never built. The Model 37 was to be of similar proportions to the XC-99; 182 ft 6 in (55.63 m) length, 230 ft (70 m) wingspan, and a high-capacity, double-deck fuselage. The projected passenger load was to be 204, with an effective range of 4,200 mi (6,800 km).
Fifteen aircraft were ordered byPan American Airways for transatlantic service. However, the fuel and oil consumption of the six 3,500 hp (2,600 kW) Wasp Major radials powering the XC-99 and B-36 meant that the design was not economically viable, and the hoped-forturboprop powerplants did not materialize fast enough. The low number of orders was not sufficient to initiate production, and the project was abandoned.
In July 1950, the XC-99 flew its first cargo mission, "Operation Elephant." It transported 101,266 pounds (45,933 kg) of cargo, including engines and propellers for the B-36, fromSan Diego toKelly Air Force Base inSan Antonio, Texas, a record it would later break when it lifted 104,000 lb (47,200 kg) from an airfield at 5,000 ft (1,500 m) elevation. In 1951, the aircraft was retrofitted with 3,800hp Pratt & Whitney R-4360-53 engines, landing gear was strengthened and a cargo-loading system installed, including an internal elevator. Bins were developed to enable quick loading of the aircraft - it was estimated the aircraft could be loaded in as little as 30 minutes.[3]
In August 1953, the XC-99 would make its longest flight, 12,000 mi (19,000 km), toRhein-Main Air Base,Germany, by way ofKindley Air Force Base,Bermuda andLajes Field in theAzores. It carried more than 60,000 lb (27,000 kg) each way. It attracted much attention everywhere it flew. The US Air Force determined that it had no need for such a large, long-range transport at that time, and no more were ordered. The sole XC-99 served until 1957, including much use during theKorean War. It made twice weekly trips from Kelly AFB to the aircraft depot atMcClellan Air Force Base,California, transporting supplies and parts for the B-36 bomber while returning by way of other bases or depots making pick-ups and deliveries along the way.
The aircraft was put on display at Kelly AFB nearSan Antonio,Texas, in 1957. Deterioration of the airframe due to the highmagnesium content was beyond local abilities to address. The aircraft was later moved to a grassy field near the base and in 1993 the USAF moved it back to the Kelly AFB. In 1995, Kelly AFB was identified for closure viaBRAC, although some portions would remain under USAF control as theKelly Field Annex to adjacentLackland AFB, it was deemed that a new location be identified for the XC-99.
Disassembly of the aircraft began at Kelly Field in April 2004 and the airframe was moved in pieces from Kelly to theNational Museum of the United States Air Force (NMUSAF) at Wright-Patterson Air Force Base.[4] By the summer of 2008, the transfer was complete and the parts were lying outside the museum.[citation needed] The aircraft had continued to suffer additional corrosion during its years in Texas and was found to be in worse condition than expected, with the restoration task being beyond the resources of the museum in a realistic time scale. Some major components such as the wing spar would need to be completely replaced.
The NMUSAF's plans for the restoration and display of the XC-99 are displayed in a case with a 1:72 scale model made by Lt Col Howard T. Meek, USAF (Ret).[5]
In an effort to preserve the aircraft for future restoration, the XC-99 was later moved incrementally to the309th Aerospace Maintenance and Regeneration Group (309 AMARG) storage facility atDavis–Monthan Air Force Base, inTucson, Arizona, where it will remain, in an area containing other aircraft belonging to the NMUSAF until the museum is able to restore it.[citation needed] In 2014,Lieutenant GeneralJohn L. Hudson,USAF (Ret), director of the NMUSAF said that there would be insufficient resources for restoration for the foreseeable future.[6]
Data fromGeneral Dynamics Aircraft and their Predecessors[9]
General characteristics
Performance
Avionics
Related development
Aircraft of comparable role, configuration, and era
Related lists
