Tim Dodd's hour-long deep dive on how rocket engines start, from solid motors to liquid engines. It covers thermal conditioning, spin-up, ignition methods, starting in space, and a step-by-step RS-25 startup.
Why Hacker News points people here: HN recommends it as the best explanation of why engine start is hard and what can go wrong.
“Here's a 1hr video from the Everyday Astronaut explaining the process and everything that can go wrong.”HN comment, 2026
“For more detail, I can recommend watching "Why starting a rocket engine is so hard" by Tim Dodd”
Explains why igniting a rocket engine is hard.
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I'd say it's pretty impressive. Building and igniting a rocket engine is hard. For more detail, I can recommend watching "Why starting a rocket engine is so hard" by Tim Dodd [0]. It's not "never been done before" impressive, they're a few years behind e.g. SpaceX's Raptor engine, which uses the same propellants, and is also reusable. But still, a new rocket engine is no small feat - the engine is probably the hardest part of a rocket. This is quite literally rocket science. [0] this video
RecommendsmagicalhippoNov 2023
“Everyday Astronaut had a couple of (IMHO) great videos”
Why rocket engines are hard.
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Everyday Astronaut had a couple of (IMHO) great videos which goes into why rocket engines are hard[1] and the Starship many-engine approach[2] specifically. [1]: this video [2]: link
RecommendsHarHarVeryFunnyMay 2026
“Here's a 1hr video from the Everyday Astronaut explaining the process and everything that can go wrong.”
Hour-long explanation of engine start and failure modes.
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Starting/igniting a liquid fueled rocket engine is an inherently complex process - everything has to be sequenced just right to get engines chilled, turbo pumps up to speed, any gaseous fuel vented and harmlessly ignited before it build up, ignition of fuel, etc. Here's a 1hr video from the Everyday Astronaut explaining the process and everything that can go wrong. this video
