How a jet engine works
Suck, squeeze, bang and blow, all happening at once instead of in turn. Air fifteen times denser, fuel at 2000 degrees, hundreds of cycles a second.
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Transcript
The Four Strokes
A jet engine does one job: suck air in, squeeze it, burn fuel in it, and blast it out the back.
Those four steps happen all at once in different zones of the engine, not one after another.
The faster and hotter the air leaves the back, the harder the engine pushes the plane forward.
The Compressor Spins
At the front sits a compressor: a shaft with dozens of fan blades, like a turbine in reverse.
As it spins, it scoops air from the front and squeezes it tighter and tighter.
Modern jet compressors can squeeze air to about fifteen times its starting density.
Fuel Burns Hot
The squeezed air enters a combustion chamber, where fuel sprays in and ignites.
The flame heats the air to roughly two thousand degrees Celsius.
This scorching gas expands and wants to rush out the back of the engine.
The Turbine Extracts Power
Before the hot gas leaves, it slams into a turbine: another set of blades on the same shaft as the compressor.
The turbine spins from the force of the hot gas, and that spin drives the compressor at the front.
The compressor and turbine feed each other; neither works without the other.
Exhaust Becomes Thrust
After the turbine, the gas is still hot and moving fast.
It shoots out a nozzle at the engine's tail, and the faster it leaves, the more it pushes the plane ahead.
About seventy-five per cent of a jet's thrust comes from the exhaust gas alone, not from the fan.
Why It Matters
The whole loop—suck, squeeze, burn, spin—happens hundreds of times per second inside a single engine.
No pistons, no on-and-off strokes; just continuous pressure and heat turning into forward motion.
That is why jets can fly twice the speed of sound and reach the edge of space.
Every sentence above was written before a single picture was drawn, then each object it names was painted for this video alone.
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