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39-564: The engine was the result of receiving an imported Power Jets W.1 X that was flown to the US from Britain in 1941, and the I-A itself was based on the design of the improved Power Jets W.2 B, the plans of which were also received. Like these designs, the I-A engine was also of centrifugal design. The I-A engine led directly to the first production US jet engine, the General Electric J31 which powered

78-440: A " mother ship " for the other modified YP-59A during remote control trials in late 1944 and early 1945. After the drone crashed during take-off on 23 March, a P-59B was modified to serve as its replacement. During diving trials in 1944, one YP-59A was forced to make a belly landing and another crashed when its entire empennage broke away. Over the following months, tests on the prototypes and pre-production P-59s revealed

117-495: A contract was placed for a "flight engine", the W.1. Unlike the Whittle WU, that began bench testing in 1937, the W.1 was a symmetrical engine designed to facilitate, after development, installation in an aircraft. The W.1 used a double-sided centrifugal compressor of Hiduminium RR.59 alloy, reverse-flow 'Lubbock' combustion chambers and a water-cooled axial-flow turbine section using 72 blades with 'fir-tree' root fixings;

156-484: A fighter to utilize it. Bell agreed and set to work on producing three prototypes. As a disinformation tactic, the USAAF gave the project the designation P-59A, to suggest it was a development of the unrelated Bell XP-59 fighter project which had been canceled. The design was finalized on 9 January 1942, and construction began. In March, long before the prototypes were completed, an order for 13 YP-59A pre-production aircraft

195-475: A hole to be broken in the brick outer wall to remove the first XP-59A. It was shipped to Muroc Army Air Field (today, Edwards Air Force Base ) in California on 12 September 1942 by train for flight testing . The aircraft first became airborne during high-speed taxiing tests on 1 October with Bell test pilot Robert Stanley at the controls, although the first official flight was made by Colonel Laurence Craigie

234-600: A multitude of problems including poor engine response and reliability (common shortcomings of all early turbojets), poor lateral and directional stability at speeds over 290 mph (470 km/h), so that it tended to "snake" and was a poor gunnery platform. The performance was greatly hampered by the insufficient thrust from its engines that was far below expectations. The Army Air Force conducted combat trials against propeller-driven Lockheed P-38J Lightning and Republic P-47D Thunderbolt fighters in February 1944 and found that

273-731: A patent for the engine in January, 1930, although he eventually allowed the patent to lapse. Power Jets Ltd was formed in March 1936. Manufacture of key engine components was undertaken by the British Thomson-Houston Company (BTH), starting in June 1936. Testing of the first engine, the WU , to demonstrate the concept, commenced on April 12, 1937. Because of a shortage of funds at Power Jets, engine components were in short supply, so development proceeded at

312-477: A result, General Electric received a contract from U.S Army Air Corps to build a turbojet based on the W.2B/23. General Electric 's extensive experience in turbocharger production made them the natural choice for producing such engine. With utmost secrecy, in October 1941 a small dedicated GE team at Lynn, Massachusetts, began the intensive development of the first US jet engine. GE initially referred to their engine as

351-453: A very slow pace. However, in the summer of 1939, shortly before war was declared, the Air Ministry suddenly realised that the jet engine was likely to become a viable means of propulsion. As a result, Power Jets received a contract for a flight engine on July 12, 1939. Shortly afterwards, a contract was placed with Gloster Aircraft Company to produce an experimental aircraft to demonstrate

390-540: A visit to England mid-1941, General Henry H. Arnold was so impressed by flight demonstrations of the Gloster E.28/39 he had witnessed that he arranged for the Whittle W.1X turbojet engine to be flown in October 1941 to the U.S in the bomb bay of a USAAC Consolidated B-24 Liberator , along with drawings for the more powerful W.2B/23 engine and a small team of Power Jets engineers, so that the US could develop its own jet engine. As

429-554: Is a single-seat, twin jet -engine fighter aircraft that was designed and built by Bell Aircraft during World War II . It was the first jet produced in the United States. As the British were further along in jet engine development, they donated an engine for the United States to copy in 1941 that became the basis for the General Electric J31 jet engine used by the P-59 a year later. Because

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468-536: The General Electric I-16 , and by April 1943 the latter had been developed to produce 1,650 pounds thrust (750 kgf). In 1941, experiments with boosting the W.1's thrust by introducing a liquid coolant were initiated, the first fluid tried being liquid ammonia which proved too effective, resulting in the engine overspeeding and pushing the thrust and rpm indicators off the scales, before later trials changed to using water, and water-methanol . A system to trial

507-559: The Power Jets W.2 . After a period of indifference, in June 1939 a demonstration of the Power Jets WU was made before a delegation of the Air Ministry , notably Dr David Pye , Director of Scientific Research . The demonstration was so successful that the Ministry quickly arranged to buy the engine to give Power Jets working capital, lending it back to them for testing. At the same time,

546-497: The Whittle W.1 ) was a British turbojet engine designed by Frank Whittle and Power Jets . The W.1 was built under contract by British Thomson-Houston (BTH) in the early 1940s. It is notable for being the first British jet engine to fly, as the "Whittle Supercharger Type W1", powering the Gloster E.28/39 on its maiden flight at RAF Cranwell on 15 May 1941. The W.1 was superseded by

585-454: The "YF2L-1" but were quickly found completely unsuitable for carrier operations . Three P-59Bs were transferred to the Navy in 1945–1946, although they kept their designations. The Navy used all five of its jets as trainers and for flight testing. Faced with their own ongoing difficulties, Bell eventually completed 50 production Airacomets, 20 P-59As and 30 P-59Bs; deliveries of P-59As took place in

624-513: The E.28 was tested with the W.1A engine, reaching a speed of 430 miles per hour (690 km/h) at 15,000 feet (4,600 m). For comparison, the Spitfire Mk. V in service at the time had a maximum speed of 374 miles per hour (602 km/h) and the Mk. IX, not yet introduced, mounting an experimental engine reached 403 miles per hour (649 km/h) at high altitude. This purely experimental aircraft and

663-556: The I-14, which was used to propel the service test YP-59A aircraft. Ultimately, General Electric found they could produce a thrust of 1,610 lbf (7.2 kN) from a package the same size and weight as the I-A, which they called the I-16 . Later, when the P-59 went into production, the aircraft was fitted with J31s, which was the USAAF designation for the I-16. Meanwhile, Power Jets continued to develop

702-451: The Type I. Engine component production was undertaken fairly openly, but the project reference "Type I Supercharger" was used to disguise the true application of the parts. The aerodynamic design and many mechanical features of the Type I were identical to that of the W.2B/23. However, there were some major differences, principally with the design of the wheelcase, which was brought into line with

741-499: The U.S. on 1 October in a Consolidated B-24 Liberator , along with drawings for the more powerful W.2B/23 engine and a small team of Power Jets engineers. On 4 September, he offered the U.S. company General Electric a contract to produce an American version of the engine, which subsequently became the General Electric I-A . On the following day, he approached Lawrence Dale Bell , head of Bell Aircraft Corporation, to build

780-564: The UK's jet program when he attended a taxiing demonstration of the Gloster E.28/39 in April 1941. The subject had been mentioned, but not in-depth, as part of the Tizard Mission the previous year. He requested and was given, the plans for the aircraft's powerplant, the Power Jets W.1 , which he took back to the U.S. He also arranged for an example of the engine, the Whittle W.1X turbojet, to be flown to

819-501: The US practice of mounting engine accessories on the engine itself. In November 1941, well before the Type I would become available for testing, General Electric started ground running of the Power Jets W.1X engine. This was the first jet engine to run on US soil, but more importantly GE gained valuable experience of testing a turbojet engine. On April 18, 1942, twenty-eight weeks after stateside work began, GE's engineers successfully ran

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858-839: The W.2B, initially with the help of the Rover Company . On April 1, 1943, Rolls-Royce took responsibility for developing the engine, and it went into small-scale production as the 1,600 lbf thrust Rolls-Royce Welland I in October, 1943. The Gloster Meteor I fighter, which entered RAF service in July, 1944, was powered by the Welland I. The W.1X is on display at the Smithsonian Institution , Washington DC. I-1A on display at Valiant Air Command - Titusville Florida Related development Comparable engines Related lists Power Jets W.1 The Power Jets W.1 (sometimes called

897-423: The engine. In May 1941, the first British jet aircraft, Gloster E.28/39 , made its maiden flight. It was powered by the 860 lbf (3.8 kN) thrust Power Jets W.1 . Prior to this first flight another engine known as the W.1X had been used in the prototype aircraft for taxiing trials. This particular one-off engine had been assembled from a collection of spare parts and was not considered flightworthy. After

936-472: The first Type I engine. True, the unit stalled before full engine speed was obtained, but this reflected British experience with the W.2B. With their vast experience of developing turbochargers, General Electric turned their expertise to improving the Type I. A modified version, the Type I-A, incorporating partitions in the blower casing to separate the air flow into each of the individual combustion chambers at

975-536: The first US jet aircraft, the Bell XP-59A Airacomet . During the late 1930s/early 1940s, a small company in England, known as Power Jets , had been developing, through a series of prototypes, a gas turbine engine to provide aircraft jet propulsion . Power Jets had been started by a Frank Whittle , who had thought of the concept of a jet engine whilst he was a young flight cadet at RAF Cranwell . He applied for

1014-490: The inner wing panels. Both production models could carry 1,590-US-gallon (6,000 L; 1,320 imp gal) drop tanks under the wings. In addition, the P-59B was provided with a 66-US-gallon (250 L; 55 imp gal) fuel tank in each outer wing panel. The crated prototype had been built on the second floor of a disused Pierce-Arrow factory, but its components were too big to fit through any elevator and required

1053-452: The jet to be transferred to nearby Harper Lake where it remained until 7 April. Five of the Airacomets, a pair of XP-59As, two YP-59As, and a P-59B had open-air flight observer cockpits (similar to those of biplanes ) fitted in the nose with a small windscreen , replacing the armament bay. The XP-59As were used for flight demonstrations and testing, but one of the latter pair was used as

1092-411: The new design dragged on, it was decided to build a test unit "early engine" using any components that were deemed unairworthy along with test items. This was assembled to become the one-off W.1X . This officially unairworthy unit powered the Gloster E.28/39 on a short 'hop' during taxiing trials in April 1941, with flight trials taking place a month later with a definitive W.1 engine. In February 1942,

1131-424: The next day. While being handled on the ground, the aircraft was fitted with a dummy propeller to disguise its true nature. When heavy rains flooded Rogers Dry Lake at Muroc in March 1943, the second prototype was towed 35 mi (56 km) to Hawes Field , an auxiliary airfield of Victorville Army Airfield, later George Air Force Base , over a public road. After one flight on 11 March, security concerns caused

1170-510: The older aircraft outperformed the jet. It, therefore, decided that the P-59 was best suited as a training aircraft to familiarize pilots with jet-engine aircraft. Even as deliveries of the YP-59As began in July 1943, the USAAF had placed a preliminary order for 100 production machines as the P-59A Airacomet, the name having been chosen by Bell employees. This was confirmed on 11 March 1944 but

1209-634: The plane was underpowered, the United States Army Air Forces (USAAF) was not impressed by its performance and canceled half of the original order for 100 fighters, using the completed aircraft as trainers. The USAAF would instead go on to select the Lockheed P-80 Shooting Star as its first operational jet fighter. Although no P-59s entered combat, the aircraft paved the way for later generations of U.S. turbojet-powered aircraft. Major General Henry H. "Hap" Arnold became aware of

General Electric I-A - Misplaced Pages Continue

1248-479: The suggestion of Whittle, began testing on May 18, 1942, and developed a thrust of 1,250 lbf (5.6 kN), at an overall pressure ratio of 3:1. On October 1, 1942, a Bell XP-59A aircraft, powered by two 1,250 lbf thrust I-A turbojet engines, made its first flight at the Muroc Army Air Field in California. Further engine developments produced a 1,400 lbf (6.2 kN) thrust engine, known as

1287-589: The technique in the E.28/39 was devised but never fitted. The Gloster E.28/39 and the Power Jets W.1 engine that powered it are on public display at the Science Museum, London . The W.1A is kept at the RAF College Cranwell, and the W.1X at the Smithsonian Institution , Washington DC. Data from Jane's Data from Jane's Related development Comparable engines Related lists Bell P-59 Airacomet The Bell P-59 Airacomet

1326-469: The third YP-59A ( S/n: 42-108773 ) was supplied to the Royal Air Force (receiving British serial RJ362/G ), in exchange for the first production Gloster Meteor I , EE210/G . British pilots found that the aircraft compared very unfavorably with the jets that they were already flying. Two YP-59A Airacomets ( 42-108778 and 42-100779 ) were also delivered to the U.S. Navy where they were evaluated as

1365-435: The turbine was later modified to use air-cooling. The turbine blades were of Firth-Vickers Rex 78 , a stainless steel developed under Dr. W. H. Hatfield . Design rating was 860 pounds-force (3.8 kN) at 16,500 rpm, increased to 17,750 rpm above 4,000 feet. With the W.1 aircraft manoeuvring would subsequently be limited (by compressor-casing stress) to 2 g . Maximum jetpipe temperature was 597 °C. As development of

1404-403: The very first flyable engine outperformed one of the most advanced high-performance aircraft in the world. After a visit to England in 1941, General Henry H. Arnold arranged for the W.1X to be flown to the U.S in October 1941, along with drawings for the more powerful W.2B engine, together with a team from Power Jets. The former became the prototype of first the General Electric I-A and then

1443-453: Was added to the contract. The P-59A had an oval cross-section, all-metal stressed skin semi- monocoque fuselage that housed a single pressurized cockpit . The mid-mounted, straight wing had two spars plus a false spar in the inner panel. The electrically powered tricycle landing gear was attached to the center spar. The pair of General Electric J31 turbojets were positioned under the wing roots in streamlined nacelles . The armament

1482-417: Was later cut to 50 aircraft on 10 October after the procurement bureaucracy had digested the earlier evaluation. The 13 service test YP-59As had a more powerful engine than their predecessor, the General Electric J31 , but the performance improvement was negligible, with top speed increased by only 5 mph and a reduction in the time they could be used before an overhaul was needed. One of these aircraft,

1521-417: Was located in the nose of the aircraft; two of the three XP-59As and most of the YP-59As had a pair of 37-millimeter (1.5 in) M10 autocannon . Later aircraft, including the production models, had one M10 autocannon and three 0.5-inch (12.7 mm) AN/M2 Browning heavy machine guns . The aircraft carried a total of 290 US gallons (1,100 L; 240 imp gal) of fuel in four self-sealing tanks in

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