How does a jet engine work?
Jet engines operate on a continuous power cycle often described in aviation as “Suck, Squeeze, Bang, Blow.” They draw in air, compress it, ignite it with fuel, and blast the resulting hot gases out the back to generate forward thrust according to Newton’s third law of motion.
Most modern commercial planes use turbofan engines, which break this process down into four distinct stages:
- Intake (Suck): A massive fan at the front pulls in huge volumes of air. In turbofans, most of this air actually bypasses the core entirely (acting like a giant propeller to provide quiet, fuel-efficient thrust), while the rest is channeled straight into the engine’s center.
- Compression (Squeeze): The air entering the core passes through rows of rapidly spinning blades. These blades pack the air tightly into a progressively smaller space, dramatically raising its pressure and temperature.
- Combustion (Bang): This super-compressed, intensely hot air enters the combustion chamber. Here, it is sprayed with jet fuel and ignited, creating a continuous, controlled high-energy explosion.
- Exhaust (Blow): The expanding hot gases blast toward the rear. Before exiting, they rush past a turbine, spinning it at high speeds. Because this turbine is connected by a central shaft to the front fan and compressor, it keeps the entire engine spinning. Finally, the gases shoot out the back nozzle, pushing the aircraft forward.