General Electric I-A
The General Electric I-A was the first working jet engine in the United States, manufactured by General Electric (GE) and achieving its first run on April 18, 1942. The engine was the result of receiving an imported Power Jets W.1X 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.2B, 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 the first US jet aircraft, the Bell XP-59A Airacomet. Design and development 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 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 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 the engine. In May 1941, the first British jet aircraft, Gloster E.28/39, made its maiden flight. It was powered by the 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 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 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,