F-1 Thrust Chamber

[Iv]

A similar design (the space shuttle main engine) brought me some peace of mind at work one day.

Nowadays, I do deep learning for a living, before that I was doing computer vision. One day I am really pissed off at some compiling issue, with a parallel code and I am like "fuck this, this is a plumbing issue! I should spend my time on algorithms and shit. Not on ordering the damn bytes of the raw pixels. I have done that for years, that should be a solved problem by now."

I go on reddit for some well-deserved outrage-slacking and stumble on the shuttle engine. "Yeah, that's what I am talking about. Now that is engineering." Then I realized it is basically a maze of pipes and pumps.

Uh, yeah, 95% of plumbing (and some metallurgy feats as well). Ok, back to coding my data pipelines then...

[mrec]

"Aerospace is plumbing with the volume turned up" -- John Carmack

[mannykannot]

There's some serious chemistry, thermodynamics and fluid dynamics involved as well.

I suppose someone is thinking that fluid dynamics is plumbing, but it would be a stretch to make that claim over issues like the size and shape of the combustion chamber, its throat and the bell, which are dependent on the characteristics of transonic and supersonic flow.

[hyperbovine]

I guess one glaring difference might be that they got this right when it mattered. Not a single Saturn V ever failed during launch. The aerospace engineering culture is vastly different than the "engineering" that goes on in ML/AI, and software development more generally. I have a lot of respect for it.

[iClaudiusX]

Here is 500 fps film of the Saturn V launch for Apollo 11, narrated by Mark Gray. It explains the sequence of events over the course of 8+ minutes (30 seconds real time).

https://www.youtube.com/watch?v=DKtVpvzUF1Y

[mywacaday]

Thanks for that, great video that led me to this, https://www.youtube.com/watch?v=ImoQqNyRL8Y, sound recording organised by Dustin from SmarterEveryDay of the latest SpaceX launch, the sonic booms of the boosters coming into land are amazing, listen with headphones!

[tigeba]

A portion of flown engine #5 from the Apollo 11 mission on display at the Kansas Cosmosphere and Space Center. It was retrieved in 2013 put on display in 2015.

[Todd]

I had a chance to see an F-1 at the Destination Moon exhibit which just opened at the Museum of Flight in Seattle. It is astonishingly large. If you're in the area, or near one of the other (few) locations where they are on display, I would definitely recommend going.

https://en.wikipedia.org/wiki/Rocketdyne_F-1#Locations_of_F-...

(The Apollo 11 command module is there, too!)

[mikejb]

> The Apollo 11 command module is there, too

Temporarily though. Normally it's exhibited at the Smithsonian in Washington DC (Which is also absolutely worth a visit).

[WalterBright]

Using the fuel to both cool the nozzle and pre-heat the fuel is just genius. (The method first appeared on the V2.)

[benj111]

Concorde used fuel as a coolant also, not to cool the jet nozzle, but ancillary things.

http://www.concordesst.com/fuelsys.html

[mrfusion]

The new raptor engine actually passes all the fuel and o2 through preburners to vaporize it. Pretty ingenious.

[ncmncm]

I am finding it astonishing that they could construct them at all, never mind get them to work and not explode.

There is a great deal of this in modern life that we successfully ignore until management failure makes it unmaintainable any more.

[dsfyu404ed]

And they did it in with slide rules and manual machining.

[gmueckl]

I don't have any data for the F-1, but the typical high power rocket engines of these days had an explosive temperament that needed to be tamed on the test stands. I recall that the SSME had a tendency to self-disassemble vilently on its test stand due to turbo pump failures that took a long time to solve. Other rocket engines probably were very similar in that regard.

[enriquto]

> ... and not explode.

But it does explode! It's just that the all the explosion power is arranged to go in the same direction

[sandworm101]

What I find most amazing about these engines isn't the complexity but rather that they operated successfully despite multiple errors. We are often told that a single failure will destroy the craft, but that really wasn't the case. Shuttle make it to orbit with multiple cracked tubes in one engine. Some bits from the recovered F-1s show clear manufacturing errors. Building something that will work at these energy levels is hard, but creating something that can survive multiple random failures and still keep ticking is spectacular.

[boyd]

The performance and track record of these engines is even more impressive when you realize that all of the design and modeling work was largely done by hand!

This is perhaps apocryphal, but I briefly worked with a guy who’d worked on the F-1 engine, and he said they’d use surplus WW2 grenades to simulate distortions/aberrations in the combustion chamber.

[mcguire]

Wrapping the turbine exhaust around the fuel return manifold would seem to be counter-productive---exhaust gasses would heat the fuel, reducing its cooling efficiency as it returns to the top of the engine.

...Unless the fuel at that point was already hotter than the turbine exhaust...

Rocket engines are weird.

[DuskStar]

The turbine exhaust forms a barrier between the uncooled portion of the nozzle and the chamber exhaust, which is significantly hotter. It's not colder than the unburned fuel being used for regenerative cooling, but the bottom of the nozzle isn't regeneratively cooled anyways.

[avmich]

This engine is still outstanding - after all these years - for the thrust per single chamber it achieves. May be only the RD-270 approached similar value for the parameter. Which is not the most important parameter, but not an insignificant one as well.