3 HN users recommended this explainer3 months2023–2026score 3
Years with an HN recommendation, 2007–2026
HN recommends it as the best explanation of why engine start is hard and what can go wrong.
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.
“Here's a 1hr video from the Everyday Astronaut explaining the process and everything that can go wrong.” (HN, 2026)
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]
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]
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]
Hour-long explanation of engine start and failure modes.
Video list and Hacker News comment labels from HackerTube (prompted by @karpathy), released under ODC-By 1.0, built on the open-index/hacker-news archive. Hacker News data is provided by Y Combinator; comments remain the work of their authors. Video titles, channel names and thumbnails belong to their creators and are shown via YouTube. HackerTube Watch is an unofficial edition. Data export of 2026-10-31.
Plays via YouTube's privacy-enhanced embed
3 Hacker News comments
From the HN archive; up to 20 kept per video, favoring different commenters. Recommendations first.