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47-513: The XB-19 project was intended to test flight characteristics and design techniques for giant bombers. Despite advances in technology that made the XB-19 obsolete before it was completed, the Army Air Corps believed the prototype would be useful for testing despite Douglas Aircraft wanting to cancel the expensive project. Its construction took so long that competition for the contracts to build

94-657: A 60 ft (18 m) wingspan, one-third scale aircraft, designated N-9M. It was to be used in gathering data on flight performance and for familiarizing pilots with the program's radical, all-wing design. The first N-9M was ordered in the original contract, but this was later expanded to three test aircraft in early 1943. A fourth was ordered a few months later after a crash of the first N-9M destroyed that airframe; this fourth N-9M incorporated various flight test-derived improvements and upgrades, including different, more powerful engines. The four aircraft were designated N-9M-1 , -2 , -A , and -B , respectively. The N-9M framework

141-473: A YB-49 all-jet airframe crashed after Air Force test pilot Forbes pulled the outer wing panels off during stall tests at 4.8  g 0 (47  m/s ). The first YB-35 airframe jet-modified to a YB-49 completed all stall tests and even demonstrated recovery from a spin. It was later destroyed after the Flying Wing's forward landing gear strut and wheel collapsed after encountering high vibration during

188-484: A bomber that could carry 4,500 kg (10,000 lb) of bombs to a round-trip mission of 16,000 km (10,000 mi). Requested performance was a maximum speed of 720 km/h (450 mph), cruise speed of 443 km/h (275 mph), and service ceiling of 14,000 m (45,000 ft). This aircraft would be able to bomb Nazi-occupied Europe in the event that Britain fell (this was similar to Nazi Germany's own Amerikabomber program design competition through

235-675: A confusion of rank and job changes, eventually cancelled the XB-35 project, while continuing testing the B-35 airframe as the YB-49, even ordering 30 of the jet-powered bombers after the first YB-49 crashed. The first and second XB-35s were scrapped on 23 and 19 August 1949, respectively. On 30 September 1943, 13 pre-production YB-35s were ordered by the Army Air Force. The first one did not fly until 15 May 1948. While some Air Force generals felt

282-545: A decade later, the dual-propeller N-1M of 1939–1941. Northrop's pioneering all-wing aircraft would lead Northrop Grumman many years later to eventually develop the advanced B-2 Spirit stealth bomber, which debuted in 1989 in US Air Force inventory. On 30 October 1941, the preliminary order for development of the B-35 Flying Wing bomber was confirmed, including engineering, testing, and most importantly

329-492: A highly unusual taxi test procedure made with the engine's fuel tanks full, causing a fire that spread rapidly. Seven incomplete airframes began conversion to jet power as YB-49B but were never finished. A third YB-35 airframe was converted to use six jet engines (two placed in under wing pods) for use as a long-range reconnaissance aircraft, designated YRB-49A . After only a few months, the Air Force's order for 30 YRB-49As

376-515: A means of reducing parasitic drag and eliminating structural weight not directly responsible for producing lift. Consolidated Vultee proposed a more conventional design with fuselage and tail, which was much larger and heavier. In theory, the B-35 could carry a greater payload faster, farther, and cheaper than a conventional bomber. In December 1941, the Army Air Forces awarded prototype contracts to both Northrop and Consolidated Vultee for

423-585: A program to save historic aircraft and the Air Force Museum had not yet been built. The XB-19 was therefore scrapped, but two of its enormous main tires were saved. Data from McDonnell Douglas aircraft since 1920: Volume   I General characteristics Performance Armament Aircraft of comparable role, configuration, and era Related lists XB-35 The Northrop YB-35/XB-35 , Northrop designation N-9 or NS-9 , were experimental heavy bomber aircraft developed by

470-545: A second aircraft, which was exercised on 2 January 1942. The first was to be delivered in November 1943, the second in April of the next year. Detailed engineering began in early 1942. A fuselage-like crew cabin was to be embedded inside the wing; it included a tail cone protruding from the trailing edge. This tail cone would contain the remote sighting stations for the bomber's gunners and a cluster of rear-firing machine guns in

517-494: A significant amount of engineering work in untested waters, the first order placed was actually for two prototypes of the XB-35, and included Northrop's plan to also build two all-wood one-third scale flying models to measure performance and stability; these were dubbed the Northrop N-9M (M standing for model). This aircraft would be used to gather flight test data on the Flying Wing design. Jack Northrop also hired part-time

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564-573: The Northrop Corporation for the United States Army Air Forces during and shortly after World War II . The airplane used the radical and potentially very efficient flying wing design, in which the tail section and fuselage are eliminated and all payload is carried in a thick wing. Only prototypes and pre-production aircraft were built, although interest remained strong enough to warrant further development of

611-581: The RLM , itself initiated in the spring of 1942). The original April 1941 USAAC proposal was first submitted to Boeing and Consolidated Aircraft Company and led to the production of the Convair B-36 . In May, one month before the USAAF was created, the contract was also extended to include Northrop, inviting it to submit a design along the lines it was already exploring. Since the new aircraft would require

658-585: The XB-35 and XB-36 occurred two months before its first flight. The plane first flew on 27 June 1941, more than three years after the construction contract was awarded. It was based at Wright Field from January to November 1942. In 1943, the Wright R-3350 engines were replaced with liquid-cooled W24 Allison V-3420 -11 by the aircraft division of Fisher Body in support of the XB-39 project. As part of

705-462: The AAF which bought them at Wright Field without testing them or assuring reliability, and then shipped them to Northrop. Microfilmed records of reports and correspondence of the XB-35 program relate that after three or four flights, power plant and propeller vibrations increased, and the very efficient contra-rotating propellers began failing with frustrating frequency. Meetings were called by Northrop, of

752-525: The AAF, Pratt & Whitney and Hamilton Standard where no one would take responsibility for correcting the AAF's engines and propellers. In addition, the AAF failed to supply the AC electrical alternator, insisting on Northrop using an onboard auxiliary power unit (APU) unit driven by an automotive engine which limited the high-altitude, high-speed XB-35 to test flights below 15,000 ft (4,600 m). The AAF also refused to allow Northrop proposed modification of

799-646: The Convair B-36 needed more development money. At that time, it appeared the B-36 program might be cancelled as well as the B-35. The USAF and the Texas Congressional delegation desired to have a production program for the large Fort Worth aircraft production factory, and Convair had much more effective lobbyists in Washington, DC. The Northrop Corporation was always a technological trailblazer, but

846-643: The N-9MB which was powered by two 300 hp (224 kW) Franklin XO-540-7 engines. The first flight of the N-9M occurred on 27 December 1942 with Northrop test pilot John Myers at the controls. During the next five months, 45 flights were made. Nearly all were terminated by various mechanical failures, the Menasco engines being the primary source of the problems. After roughly 22.5 hours of accumulated flight time,

893-628: The Northrop "all-wing" designs. There are long-standing conspiracy theories about the cancellation of the Flying Wing program; specifically, an accusation from Jack Northrop that Secretary of the Air Force Stuart Symington attempted to coerce him to merge his company with the Atlas Corporation-controlled Convair . In a 1979 taped interview, Jack Northrop claimed the Flying Wing contract

940-414: The XB-35 itself began in earnest. Unlike conventional aircraft, truly "tailless" flying wings do not have a rudder for lateral control, so a set of clamshell-like, double split flaps (so-called flaperon , a portmanteau of flap and aileron) on the trailing edge of the wingtips were used. When aileron control was input, they were deflected up or down as a single unit, just like an aileron. When rudder input

987-524: The XB-35s until the government fixed their propulsion system. Concurrently, the AAF ordered Northrop to convert two of the YB-35 airframes to YB-49s, essentially substituting eight jet engines for four reciprocating engines. As a result, the airframe promptly flew to more than 40,000 ft (12,000 m) and topped 520 mph (840 km/h) in flight tests, verifying the XB-35 air frame's aerodynamics, but at

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1034-450: The aircraft in 1982 and began the labor-intensive restoration process. For the next two decades, former Northrop employees and other volunteers restored the N-9MB to its final flight configuration. Since 1993, the yellow-and-blue Flying Wing has been exhibited, with flight demonstrations at several airshows every year. In April 2006, the N-9MB suffered an in-flight engine fire. The aircraft was landed safely with limited damage. Donations to

1081-544: The aircraft's center line, four above and below the outer wings, and four in the "stinger" tail cone. The B-35 would take advantage of a new aluminum alloy devised by Alcoa ; it was considerably stronger than any alloy used previously. In June 1946, the XB-35 made its first flight, a 45-minute trip from Hawthorne, California , to Muroc Dry Lake, without incident. The XB-35's engines and propellers were AAF property and had not been tested for engine-propeller compatibility by either Pratt & Whitney, Hamilton Standard, or by

1128-577: The bomb bays to carry the standard Mk. 3 atomic bomb, while at the same time declaring the AF would not buy the bomber unless it could carry the A-bomb. Northrop reluctantly agreed to try a single-rotation propeller, which slightly increased takeoff distance and a reduced rate-of-climb and maximum speed. Problems with the quartet of contra-rotating propellers ' shafts comprising each aircraft's drive-line system continued until finally Jack Northrop himself grounded

1175-404: The competing propeller-driven B-36 was obsolete by that time and had just as many or even more development problems, the Air Force needed a very long-range, post-war atomic bomber to counter the perceived Soviet threat. It had more faith that the B-36's "teething" problems could be overcome, compared to those of the new and radical "Flying Wing", the unofficial name that was later associated with all

1222-451: The design as a jet bomber, under the designation YB-49 . The B-35 was the brainchild of Jack Northrop , who made the flying wing the focus of his work during the 1930s. In 1941 before the USA entered World War II, Northrop and Consolidated Vultee Corporation had been commissioned to develop a large wing-only, long-range bomber designated XB-35 and XB-36. Northrop advocated a "flying wing" as

1269-495: The development of the full size, 172-foot (52 m) wingspan Northrop XB-35 and YB-35 flying wing long-range, heavy bomber. First flown in 1942, the N-9M (M for Model) was the third in a lineage of all-wing Northrop aircraft designs that began in 1929 when Jack Northrop succeeded in early experiments with his single pusher propeller , twin-tailed, twin-boom, all stressed metal skin Northrop X-216H monoplane , and

1316-436: The effectiveness of propeller control. After only 19 flights, Northrop grounded the first XB-35; the second aircraft was grounded after eight test flights. During this time, the contra-rotating propellers were removed and replaced with four-blade single-rotation propellers. In addition to having continued drive shaft vibration problems, the new single-rotation props greatly reduced the aircraft's speed and performance. Furthermore,

1363-411: The first N-9M crashed approximately 12 miles (19 km) west of Muroc Army Air Base (now Edwards Air Force Base ) on 19 May 1943. The pilot, Max Constant, was killed as he attempted to recover the aircraft from a right-hand, 60° nose-down spin. The investigation found that Constant had suffered control reversal , the control column had been pressed against his chest during his recovery attempt from

1410-555: The first delivery date back to 1947. Seeing that it would almost certainly never be ready in time for the war, the Army Air Forces canceled the production contract, though the Air Technical Services Command continued to run the program for research purposes. Actual flight tests of the aircraft revealed several problems: the contra-rotating props caused constant heavy drive-shaft vibration and the government-supplied gearboxes had frequent malfunctions and reduced

1457-400: The independent nature of Jack Northrop often collided with the political wheeling-and-dealing in Washington that tended to run huge military allocations. Consequently, the B-36 prevailed, with just over 380 aircraft built. Furthermore, earlier the same year, when the YB-49 jet bomber was cancelled, Northrop received a smaller production contract for its F-89 Scorpion fighter as compensation for

Douglas XB-19 - Misplaced Pages Continue

1504-530: The intricate exhaust system turned into a fiasco to maintain. After only two years of use, the engines already showed signs of metal fatigue . In the end, the program was terminated due to its technical difficulties and the obsolescence of its reciprocating propeller engines, and the fact it was far behind schedule and over budget. Another contributing factor to the program's failure was the tendency of Northrop to become engaged in many experimental programs, which spread its small engineering staff far too wide. While

1551-446: The leading aeronautical designer of the day Theodore von Kármán , to evaluate and who approved of Northrop's initial design, and to start building the tooling for building the prototypes ... as explained in detail in the book "Goodbye Beautiful Wing" by Terrence O'Neill ( ISBN   978-0979012129 ). The N9Ms would also be used as a flight trainer, to familiarize pilots with the radical, all-wing concept. Early in 1942, design work on

1598-424: The lost Flying Wing contract. Data from Northrop Flying Wings : a history of Jack Northrop's visionary aircraft General characteristics Performance Armament Related development Aircraft of comparable role, configuration, and era Related lists Northrop N-9M The Northrop N-9M was an approximately one-third scale, 60-foot (18 m) span all-wing aircraft used for

1645-461: The museum were solicited for its repair, and the aircraft was fully repaired to flight status. It was flown again during the annual Chino airshow on 15–16 May 2010. On 22 April 2019, the N-9MB was destroyed shortly after takeoff, when it crashed into a prison yard in Norco, California . The pilot was killed but no ground casualties were reported. The National Transportation Safety Board attributed

1692-403: The piston engines made the B-35 obsolete, it remained superior in overall performance and range to its competitor, the Convair B-36, and General Hoyt Vandenberg wrote that only the B-35 and the B-36 had adequate range for the Air Force's primary mission, and nothing comparable would be available until the mid-1950s. Only the first YB-35 was ever flown. Multiple flight testing demonstrated that it

1739-529: The price of range. The prop-version had a design range capable of reaching targets 4,000 mi (6,400 km) away, but the jet-engine version's range was cut nearly in half. The new version disqualified it for the Air Force's top-priority mission as a strategic bomber, which at that time meant striking at the USSR's industrial and military complexes in the Ural Mountains. The Air Force, itself involved in

1786-545: The production aircraft. In the midsection of the cabin, there were folding bunks for off-duty crew on long missions. The aircraft's bomb load was to be carried in six smaller bomb bays, three in each wing section, fitted with roll-away doors; this original design precluded the carrying of large bombs, and the early atomic bombs , without bomb bay redesign and modifications. Production aircraft would have defensive armament of twenty 0.5 in (12.7 mm) machine guns or 20 mm cannon, carried in six turrets, two turrets along

1833-474: The program, it was equipped with engine driven auxiliary powerplants. After completion of testing, the XB-19 was earmarked for conversion into a cargo aircraft, but modifications were not completed, and the aircraft flew for the last time on 17 August 1946. It was eventually scrapped at Tucson in June 1949. The new U.S. Air Force had plans to save the XB-19 for eventual display, but in 1949 the Air Force did not have

1880-470: The steep spin, preventing him from parachuting to safety. Actions were taken to fix this problem and prevent it from happening on other N-9M test aircraft. When Northrop's Flying Wing bomber program was canceled, all remaining N-9M flight test aircraft, except for the final N-9MB, were scrapped. For more than three decades, it slowly deteriorated until the Chino, California Planes of Fame Air Museum acquired

1927-644: Was a U.S. Navy designation for one YB-35 airframe to be used for development trials; the project was canceled while still in the planning stage. The U.S. Army Air Forces had originally ordered 200 production model B-35s. Since Northrop's facilities were not up to the task of producing them, the Glenn L. Martin Company agreed to undertake mass production. This proved irrelevant when the aircraft had too many development problems. Even disregarding these, so many of Martin's engineers had been drafted by 1944 that Martin pushed

Douglas XB-19 - Misplaced Pages Continue

1974-404: Was airworthy; it was then parked and ignored for more than a year until being scrapped on 20 July 1949. The unfinished YB-35 #2, was scrapped almost a month later, on 19 August 1949. The other 11 of 13 YB-35 aircraft ordered underwent conversion to other power plants. Two of those airframes were converted to use eight Allison J35 jet engines and designated YB-49 . The second YB-35 converted to

2021-414: Was cancelled because he would not agree to a merger because Convair's merger demands were "grossly unfair to Northrop." When Northrop refused, Symington supposedly arranged to cancel the B-35 and B-49 program. Symington became president of Convair after he left government service a short time later. Other observers note that the B-35 and B-49 designs had well-documented performance and design issues while

2068-414: Was made, the two surfaces on one side opened, top and bottom, creating drag, and yawing the aircraft. By applying input to both rudder pedals, both sets of surfaces were deployed creating drag so that the airspeed or the glide angle could be manipulated. On 22 November 1941, the United States Army Air Forces (USAAF, or AAF) signed the development contract for an XB-35; the contract included an option for

2115-433: Was partially constructed of wood to reduce its overall weight. The wings' outer surfaces were also skinned with a strong, specially laminated plywood . The central section (roughly equivalent to the fuselage ) was made of welded tubular steel. The aircraft were originally powered by two 290 hp (216 kW) Menasco C6S-1 "Buccaneer" inverted air-cooled straight-six engines , driving twin-bladed propellers , except for

2162-416: Was suddenly cancelled without explanation. The sole YRB-49A built flew 13 test flights and then was returned to Northrop's Ontario Airport. The last of Northrop's big Flying Wings sat abandoned at the airport's edge for two years and was finally ordered scrapped on 1 December 1953. In order to test the advanced Northrop T37 Turbodyne turboprop engine, produced by a Northrop subsidiary, the ultimate YB-35A

2209-572: Was to be converted to a single EB-35B test aircraft (in this case the prefix "E" for the designation meant "Exempt," not the later Electronic). The test aircraft would use two of the powerful T37 engines, each driving a pair of contra-rotating, paddle-blade propellers; the first planned ground tests were to be made using a single T37 engine. When the EB-35B project was canceled, the Air Force had Northrop's Turbodyne engine name, all its patents, and technical data reassigned to General Electric . The XB2T-1

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