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The Evolution Of Jet Engines Essay Research

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The Evolution of Jet Engines

The jet engine is a complex propulsion device which draws in air by

means of an intake, compresses it, heats it by means of an internal combustion

engine, which when expelled it turns a turbine to produce thrust, resulting in a

force sufficient enough to propell the aircraft in the opposite direction

(Morgan 67). When the jet engine was thought of back in the 1920’s the world

never thought it would become a reality, but by 1941 the first successful jet

flight was flown in England. Since then the types of engines have changed, but

the basic principals have remained the same.

In 1921 thoughts of a jet engine were based upon adaptations of piston

engines and were usually very heavy and complicated. These thoughts were

refined in the 1930’s when the turbine engine design lead to the patent of the

turbojet engine by Sir Frank Whittle of Great Britian. It was Sir Whittle’s

design that lead Great Britian into the jet age with the first successful flight.

At the same time, the Germans were designing there own jet engine and aircraft

which would be one of the factors that kept Germany alive in World War II. With

technological advances by the allies a prototype turbojet known as the “Heinkel

He 178″ came into a few operational squadrons in the German, British, and the

American air forces towards the end of World War II. These jets finally helped

the allies to win the war against the axis powers(Smith 23-27).

A later development in the jet industry was the overcoming of the sound

barrier and establishing normal operations up to and beyond twice the speed of

sound. Also air force bombers and transports were able to reach and cruise at

supersonic speeds(Silverstein 56-70). In the late 1950’s civil transcontinental

jet services started with the Comet 4 and the Boeing 707. In the mid 1960’s all

major jet manufacturing companies revised their present engines with new

materials such as aircraft aluminium which made them lighter and turbine changes

so they could compress the air at a much higher pressure so the engine can

produce much more thrust.The first supersonic airliner is the twin turbojet

Concorde which flies at over twice the speed of sound which was brought into

regular service in 1976(Smith 27-30). The one company that dominates the

private jet industry is Bombardier which makes the Learjet turbofans, they have

an approximate cruising distance of 1880 nautical miles(Jennings 103).

In the future, turbojet engines will continue to further develop due to the

technological advances made. As in graphite composite wings, thermoplastic

chassis, and kevlar skins that have changed the weight of modern planes and

gliders. With these and other developments jet engines will be honed to produce

greater thrust without increases in weight or size. Which will involve small

refinements rather than major changes to the existing engine and engine

compartment. In the near future there will be a substantial reduction of noise

emitted from the jet engine, due to a change in materials and a reduction of

vibration in the housing. Right now the jet industry has over one thousand jets

operational at one time, which poses the threat of malfunction and crashes. With

the new computer analysis of problems and the new materials found in the

internals of the engines, there is less of a risk of malfunction than in the

past.

Many factors have lead to the popular take over of the jet, replacing the

traditional propeller driven planes. Some of the basic reasons are the speed,

fuel economy, and endurance of the jet engine oveer piston-driven engines.

Together with the new refinements and the currently changing jet industry,

future transportation will become faster and safer for the flier.




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