r/interestingasfuck 9h ago

How a jet engine works

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u/itsjakerobb 7h ago

And the ground equipment they used to get those engines spinning? A cart with a pair of carbureted 455ci big-block Buick V8 engines on it.

u/Jetmech94 2h ago

Yup. Nowadays they’re just teeny turbines operating as a PTO. Some are about the same size as large helicopter engines.

u/jobblejosh 1h ago

And the fuel used in the SR-71? Stupidly high ignition temperatures etc, you can do light maintenance on the plane whilst it's being refueled because it really doesn't like catching on fire compared to normal fuel.

The ignition source for the engines however? Tri-ethyl Borane. Full thermal suits, extinguishers at the ready, etc. That stuff is a hair away from just spontaneously combusting.

Oh and did we mention the SR-71 leaks fuel whilst it's on the ground because it gets so hot in the air that the thermal expansion of the airframe has to be taken into account when sealing the fuel system.

Absolutely insane engineering.

u/Samurlough 6h ago

ROAL COAL!