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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