The first U.S. jet engine was built in 1942 by General Electric (GE). This engine, GE I-A, was designed after the British Whittle turbojet engine. In Britain, jet engine development also progressed rapidly and soon attracted the attention of USAAF General "Hap" Arnold. In 1941, after witnessing a flight of the Whittle powered Gloster E28/39 jet prototype, he negotiated with the Air Ministry to produce the Whittle/GE I-A in the United States. From this British "seed" engine, much of the US jet aircraft engine industry took root.
The control for the GE I-A was a hydro-mechanical governor, which metered the fuel flow going into the engine to be proportional to the difference between the set speed and the actual speed of the turbine. To prevent the engine from flame-out, a minimum-flow stop was added to the fuel metering valve. To prevent the engine from over-temperature, a maximumflow schedule was also incorporated. This system possessed the basic functionality of controlling a single-spool turbojet engine.
The first American jet-propelled airplane was the Bell P-59 Airacomet powered by two General Motors engines that were based on a Whittle design. The P-59 was under secret development in the early 1940's and first flew on October 1, 1942. The P-59 had twin jet engines mounted near the wing root section. The arrangement resulted in a swaying motion in flight due to slight variations in the jet flow from the twin nozzles. The P-59 was considered unsuitable as an operational fighter but was relegated to a training role for jet pilots. Bell considered a single engine version of the P-59 but subsequently relinquished the project to Lockheed. Lockheed proceeded to develop the single-engine P-80 that became the first U.S jet fighter.
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