Talks to Watch

Why Can't we Remake the Rocketdyne F1 Engine?

4.2M views · Jul 24, 2018 · 5:04 · 1 HN recommender · 5 mentions · discussed 2019–2022

Short Curious Droid video on why NASA could not simply rebuild the Saturn V's Rocketdyne F-1 engine for the SLS boosters. It explains that the engines were hand-tailored and that much of the know-how was never documented, so the blueprints were not enough.

Why Hacker News points people here: Cited as the standard illustration of lost tacit knowledge and why old blueprints cannot be turned back into hardware.

“TLDR: everything was handcrafted, notes were not made or lost”HN comment, 2021

What Hacker News said 5

RecommendslmilcinJul 2021

“TLDR: everything was handcrafted, notes were not made or lost”

Handcrafted engines and lost notes make blueprints insufficient to rebuild the F-1.

Full comment

Sure. Not a source but still interesting. this video (Why Can't we Remake the Rocketdyne F1 Engine?) TLDR: everything was handcrafted, notes were not made or lost, people have retired or passed away and today's engineers don't know the tricks that the original engineers used. Effectively, existing blueprints are not enough to rebuild the engine.

in “SpaceX Falcon Heavy rocket will launch NASA's Europa Clipper to icy Jupiter moon” · view on HN
Cites itest31Jul 2019

“each rocket engine was hand-tailored to the demands of the individual rocket”

Why the F-1 engine can't be rebuilt from surviving plans.

Full comment

Yup that's what curious droid's video on this is saying as well [1]. Basically the plans all were off a little bit and each rocket engine was hand-tailored to the demands of the individual rocket by these skilled people you mentioned. They did document their changes but only on scrap notes that since were lost. The plans themselves that were archived don't contain those notes and even if they had them, you couldn't find people with such skills any more. [1]: this video

in “How Ancient Rome’s Concrete Has Survived 2,000 Years (2017)” · view on HN
Cites itest31Mar 2021

“Each engine was custom tailored with small modifications here and there.”

Why Saturn V engines couldn't be recreated from plans.

Full comment

Reminds me of how NASA had to design completely new rocket engines for SLS because while they still had the plans for the Saturn-V rocket engines, back then plans weren't followed to such high accuracy as nowadays a 3D model would be followed. Each engine was custom tailored with small modifications here and there. The knowledge to custom tailor them was lost, so they went with designing new engines from scratch instead. this video

in “The Air Force is having to reverse engineer parts of its own stealth bomber” · view on HN
Cites itxyzzy21Mar 2021

“The TACIT knowledge and technologies required to go with the blueprints died with them.”

Tacit knowledge behind the F-1 engine was lost.

Full comment

You'd have to redesign it from scratch - it would be faster. Which is what happened with the SLS engine/launch vehicle. Duplicating the F1 would involve technology and knowledge of individual engineers who are dead and corporations that no longer exist. The TACIT knowledge and technologies required to go with the blueprints died with them. link link this video

in “Audi abandons combustion engine development” · view on HN
Cites itCountSessineFeb 2022

“Machining and engineering skills as they relate to manufacturing are different now.”

Machining and engineering skills have changed since the F-1 era.

Full comment

Technical know how, mostly. But in expected ways. Machining and engineering skills as they relate to manufacturing are different now. this video

in “SpaceX’s monstrous, dirt-cheap Starship may transform space travel” · view on HN