The turbojet was first invented in 1928 by Frank whittle. Heinkel he 178 was the first aircraft to fly under turbojet power.The glossary 2839 gloucester whittle made the first British jet engine flight in 1941. Turbojet engine has several parts the turbojet can be thought of as a high tech propeller inside of a duct called a diffuser driven by gas generator the core of a jet engine is a gas generator that creates high pressure gas to power a turbine this setup has compressor combustor and turbine section commercial aircraft tend to used high bypass turbofin engine which are suitable only. for subsonic flight flying slower than the speed of sound or 12-25 kilometer per hour. these engine optimize fuel efficiency and reduce noise in contrast military fighter jet used low. bypass turbojet engine which are generally noisier than commercial aircraft engine.most have afterburners for additional thrust and noise and can fly faster than the speed of sounds. supersonic or faster than 12-25 kilometer per hour. In certain condition this can create a sonic boom.The engine need higher power to weight ratios for speed and maneuverability. Iterbojet is the simplest kind of jet engine basic on a gas turbine most modern passenger and military aircraft are power by gas turbine engine which are also called jet engine. The first and simplest type of gas turbine is the turbojet it is a basic rocket jet that move. a plane forward by firing a hot jet of exhaust backward the exhaust leaving the engine. is much faster than the cold air engine it and that how a turbojet makes its thrust. turbojet the basic idea of the turbojet engine is simple air takes in from an opening in the front of the engine then it is compressor three to twelve times is original pressure in compressor. Fuel is added to the air and burned in a combustor chamber to raise the temperature. of the fluid mixture to about 1100 fahrenheit to 1300 fahrenheit the resulting hot air is passed. through a turbine which drives the compressor if the turbine and compressor are efficient. the pressure at the turbine discharge will be nearly twice the atmospheric pressure. and this excess pressure is send to the nozzie to product a high volocity stream of gas which. produces a thrust substantial increases in thrust can be obtained by employing an afterburners. It is a second combustion chamber positioned after the turbine and before the nozzie.The afterburners increases the temperature of the gas ahead of the nozzie the result of this increases in temperature is an increases of about 40 percent in thrust at takeoff and a Much Large percent at high speed one the plane is in the air the turbojet engine is a reaction engine. In reaction engine expanding gas push hard against the front of the engine the turbojet. sucks in air and compressor or squeezes it the gas flow through the turbine and make it spin. these gas bounce back and shoot out of the rear of the exhaust pushing the plane forward.