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 Britain
. It was Sir Whittle's design that lead Great Britain 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