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Jet engine

A model of a jet engine, showing the working partsA model of a jet engine, showing the working parts All jets work in the same way: hot, compressed air is expelled from the back of the engine, driving it forwards. There are several kinds of jet engine, including turbojets, turbofans, turboprops and turboshafts. Airliners, business jets, military jets, missiles and some speed boats are powered by jet engines. An aeroplane's jet engines are contained within engine cowlings (casings) usually attached to the wing undersides or either side of the fuselage. The front entrance to the engine is known as the intake.

How it works

A diagram of a simple jet engine: a turbojetA diagram of a simple jet engine: a turbojetThe air is drawn in through the opening at the front of the engine and compressed by spinning blades. Then, in the combustion chamber, it is mixed with kerosene fuel and the air-fuel mixture is ignited. The hot exhaust gas produced by the burning fuel escapes at speed through the rear of the engine, powering a turbine, which drives the compressor, as it rushes past. The backward-flowing gases provide a forward thrust, like the kick of a rifle after a bullet is fired.

A car powered by two turbofan engines is the current holder of the land speed record: the ThrustSSC (1228 km/h or 763 mph).

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