So you need to Pick a problem: push an airliner through the sky

Two hundred tonnes of airliner, and up here there's nothing to push against except air.

1. So you push the air, throwing lots of it backward. A giant fan gulps over a tonne of it every second.
2. And about ninety percent of it flows around the engine's core. That bypass air makes most of the thrust.
3. So the rest dives into the core, where a compressor squeezes it to forty, even sixty times its starting pressure.
4. But what spins all those blades?
5. So the fire does. Fuel burns nonstop, hot gas spins a turbine, and shafts carry that power to the compressor and the fan.
6. But that gas is hotter than the turbine blades' melting point.
7. So cooler air seeps out of tiny holes and wraps each blade in a protective film.

Suck, squeeze, bang, blow.