[SR] Jet Engines

        When humans first observed how birds fly in the sky, they realized that it not only took the birds their light weight, and wings to get them flying, they needed speed. And since the day the Wright brothers built the Wright Plane, the propulsion of aircraft has also evolved, and today, the propeller that had propelled once propelled aircraft into the sky, has been replaced by a bigger, more efficient and faster alternative, the jet engine.

        Aviation is the youngest of all commercial transport and has the fastest growth as well. Many of us has flown on an aircraft before, yet many of us do not understand how the jet engine works. It is a fairly simple concept really, the idea is to suck air in and blast it out at higher speeds, but the technology involved with it is far more complicated.

        To start with, there are 4 types of engines, turbojet, turbofan, propfan, and turboprop.

Propfan

Turbofan

Turbojet

Turboprop

        

       A jet engine works by first sucking in and compressing the surrounding air through the axial compressor. The axial compressor comprises of both moving and stationary blades. The moving blades suck in the air while the stationary ones guide the air and ensures the air enters at the right angle. Then the air flows into the compressor which rotates at very high speed adding energy to the airflow and at the same time squeezing  it into a smaller space. They can compress the air in a 44:1 ratio. The air then moves into a combustion chamber where fuel is mixed in with the air and is ignited and the air would flow at a much faster speed. The temperature of this air would melt the turbine so the compressor directs some air into through a separate channel and this cooler air acts as a coolant for the jet engine. The turbine is another series of blades and it would make the air flow faster. The gas then exits through the nozzle and blasts the aircraft forward.  

Reverse Thrust

As the name implies, it literally sucks air in from the back and blasts it out from the front. Have you ever noticed when landing, a loud roaring of the engine can be heard, that's reverse thrust taking place, it slows down the plane considerably for landing.

Thrust reversal, also called reverse thrust, is the temporary diversion of an aircraft engine's exhaust or changing of propeller pitch so that the thrust produced is directed forward, rather than aft. This acts against the forward travel of the aircraft, providing deceleration. Thrust reversers are used by many jet aircraft to help slow down just after touch-down, reducing wear on the brakes and enabling shorter landing distances. It is also available on many propeller driven aircraft through reversing the controllable pitch propeller to a negative angle.