Aces High Bulletin Board
General Forums => Aircraft and Vehicles => Topic started by: earl1937 on October 23, 2013, 02:02:47 PM
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:airplane: The USAF was officially OK with the performance of the B-29, but for the want of a better aircraft, which could carry more bombs, fly further and faster and higher, the order was given to Boeing to develop such an aircraft. Following are some excerpts from various souches to tell the story of the development and use of the B-50, which was the first aircraft to fly non-stop around the world!
Development of an improved B-29 started in 1944, with the desire to replace the unreliable Wright R-3350 engines with the more powerful four-row, 28-cylinder Pratt & Whitney R-4360 Wasp-Major radial engine. A B-29A-5-BN (serial number 42-93845) was modified by Pratt & Whitney as a testbed for the installation of the R-4360 in the B-29, with four 3,000 hp (2,200 kW) R-4360-33s replacing the 2,200 hp (1,600 kW) R-3350s. The modified aircraft, designated XB-44 Superfortress, first flew in May 1945. The planned Wasp-Major powered bomber, the B-29D, was to incorporate considerable changes in addition to the engine installation tested in the B-44. The use of a new alloy of aluminum, 75-S rather than the existing 24ST, gave a wing that was both stronger and lighter, while the undercarriage was strengthened to allow the aircraft to operate at weights of up to 40,000 lb (18,000 kg) greater than the B-29. A larger vertical fin and rudder (which could fold to allow the aircraft to fit into existing hangars) and enlarged flaps were provided to deal with the increased weight.
(http://i1346.photobucket.com/albums/p684/earl1937/b50_n_zps9775074a.jpg)
Note the larger engine nacelles and the larger vertical stabilizer and rudder!
The first production B-50A (there were no prototypes, as the aircraft's engines and new tail had already been tested) made its maiden flight on 25 June 1947, with a further 78 B-50As following. The last airframe of the initial order was held back for modification to the prototype YB-50C, a planned version to be powered by R-4360-43 turbo-compound engines. It was to have a longer fuselage, allowing the two small bomb-bays of the B-29 and the B-50A to be replaced by a single large bomb-bay, more suited to carrying large nuclear weapons. It would also have longer span wings, which required additional outrigger wheels to stabilize the aircraft on the ground. Orders for 43 B-54s, the planned production version of the YB-50C, were placed in 1948, but the program was unpopular with Curtis LeMay, commander of Strategic Air Command (SAC), as being inferior to the Convair B-36 and having little capacity for further improvement, while requiring an expensive redevelopment of air bases owing to the type's undercarriage. The B-54 program was therefore canceled in April 1949, work on the YB-50C being stopped prior to it being completed.
While the B-54 was canceled, production of less elaborate developments continued as a stopgap until jet bombers like the Boeing B-47 and B-52 could enter service. Forty-five B-50Bs, fitted with lightweight fuel tanks and capable of operating at higher weights, were built, followed by 222 B-50Ds, capable of carrying underwing fuel tanks and distinguished by a one-piece plastic nose dome. To give the Superfortress the range to reach the Soviet Union, B-50s were fitted to be refueled in flight. Most (but not all) of the B-50As were fitted with the early "looped hose" refueling system, developed by the British company Flight Refuelling Limited, in which the receiving aircraft would use a grapple to catch a line trailed by the tanker aircraft (normally a Boeing KB-29) before hauling over the fuel line to allow transfer of fuel to begin. While this system worked, it was clumsy, and Boeing designed the alternative Flying Boom method to refuel SAC's bombers, with most B-50Ds being fitted with receptacles for Flying Boom refueling.
(http://i1346.photobucket.com/albums/p684/earl1937/800px-KB-50_Refuelling_zps35e70a4d.jpg)
(http://i1346.photobucket.com/albums/p684/earl1937/KB-50refuelingF-86_zps6221f05c.jpg)
KB-50 refueling F-86, note the landing gear down on the F-86 to get slow enough for the refueling procedure!
Revisions to the B-50 (from its predecessor B-29) would boost top speed to just under 400 mph (644 km/h). Changes included:Larger engines,Redesigned engine nacelles and engine mounts.Enlarged vertical tail and rudder (to maintain adequate yaw control during engine-out conditions),Reinforced wing structure (required due to increased engine mass, larger gyroscopicforces from larger propellers, greater fuel load, and revised landing gear loading),Revised routing for engine gases (cooling, intake, exhaust and intercooler ducts; also oil lines),Upgraded remote turret fire-control equipment,Landing gear strengthened and takeoff weight increased from 133,500 lb / 60,555 kg to 173,000 lb / 78,471 kg,Increased fuel capacity with underwing fuel tanks being added,Improvements to flight control systems (the B-29 was difficult to fly; with increased weights the B-50 would have been more so).,Nose wheel steering rather than a castering nose wheel as on the B-29
Redesigned with a large upper fuselage grafted on, the B-50 design would form the basis for the Boeing 377 series of airliners and C-97/KC-97 military transports, with 816 of the KC-97 built. The B-29 and B-50 were phased out with introduction of the jet-powered B-47 Stratojet. The B-50 was nicknamed "Andy Gump" because the redesigned engine nacelles reminded aircrew of the chinless newspaper comic character popular at the time.
Boeing built 370 of the various B-50 models and variants between 1947 and 1953, the tanker and weather reconnaissance versions remaining in service until 1965.
The first B-50As were delivered in June 1948 to the Strategic Air Command's 43d Bombardment Wing, based at Davis-Monthan AFB, Arizona. The 2d Bombardment Wing at Chatham AFB, Georgia also received B-50As; the 93d Bombardment Wing at Castle AFB, California and the 509th Bombardment Wing at Walker AFB, New Mexico received B-50Ds in 1949. The fifth and last SAC wing to receive B-50Ds was the 97th Bombardment Wing at Biggs AFB, Texas in December 1950. The mission of these wings was to be nuclear capable and in wartime to be able to deliver the atomic bomb on enemy targets if ordered by the President.
The 301st Bombardment Wing at MacDill AFB, Florida received some B-50As reassigned from Davis-Monthan in early 1951, but used them for non-operational training pending the delivery of B-47A Stratojets in June 1951. The B-50 was built as an interim strategic bomber to be replaced by the B-47 Stratojet, but delays to the Stratojet forced the B-50 to soldier on until well into the 1950s.
(http://i1346.photobucket.com/albums/p684/earl1937/KC97_zps9d630fdc.jpg)
A pic of the last use of the B-50 airframe by Boeing! They added a "upper" deck, but used the same vertical stab and rudder, plus same engines as B-50, same landing gear and nose wheel. This aircraft lasted until late in the 50's, when the Boeing KC-135 came on board SAC command and replace all of the 97's and KB-50's.
(http://i1346.photobucket.com/albums/p684/earl1937/Boeing_B-50_USAF_zps678fc5f0.jpg)
A WB-50J "Hurricane Hunter" in flight, note the radar dome on belly of the aircraft!
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What a beautiful monster! :)