Yeah, like that's gonna happen. Picture launching like, 30-40 rockets to get from a 50% chance to explode down to a 5% chance, when each of them has a 200 progress requirement and costs 40-50 R each. We can probably build in some extra safety but not by launching more and more rockets until it's 5% unreliable.
Per Aspera (Space Agency Plan Quest)
- Thread starter Shadows
- Start date
- Original
grimely
Twink Death Sufferer
Considering that this quest consciously tries to emulate and celebrate early space exploration, I think it is in fact very likely we will get launch successes to that point, since 5% failure rate is actually worse than what NASA eventually insisted on after Apollo 1. You know. In real life.
Well, the R-4 is currently sitting at what, 40, 35% failure rate? And a fresh design would be starting over from scratch at 50%. But the R-4 is only 2 metric sputniks, so even with all the changes we can do to optimize it, I have doubts that the R-4a will have enough payload to be human-rated. So, we need either a lot of boosters (which is why my plan takes Booster research.) or we need a clean-sheet design that's quite a bit larger. But in either case I think we'll need to do more than a few sounding launches to lower the failure rate to 5% before 1960.
- Location
- [REDACTED]
[X] Plan: Promises First, Party Later
The R-4 is probably going to be what we use to launch our weather sats, and I think that alone will probably be worth trying to bring down the failure rate.
The R-4 is probably going to be what we use to launch our weather sats, and I think that alone will probably be worth trying to bring down the failure rate.
Hopefully this weekend I'll get a chance to read through the textbook I have on rocket design and use that to estimate the upper limit of R-4 performance, assuming we add on boosters to bring us up to 30 t GLOW, use balloon tanks, etc.
Mercury-Atlas 6 put 13.5 metric sputniks into orbit; I think it's conceivable that we could lower that down to, say, 12 metric sputniks with aggressive mass cutting. When looking at how large the Atlas rocket was, it's worth keeping in mind that it was doing stage and a half to orbit because it was literally just an ICBM- it didn't drop any empty tanks on the way.
Mercury-Atlas 6 put 13.5 metric sputniks into orbit; I think it's conceivable that we could lower that down to, say, 12 metric sputniks with aggressive mass cutting. When looking at how large the Atlas rocket was, it's worth keeping in mind that it was doing stage and a half to orbit because it was literally just an ICBM- it didn't drop any empty tanks on the way.
Solarstream
It's all in the cards
- Location
- Zombie World
- Pronouns
- He/Him
[X] Plan: Promises First, Party Later
- Location
- the Republic
- Pronouns
- He/They
Even 15R a turn isn't that big a deal, honestly, if we're talking about a single die.
- Pronouns
- She/Her
C_Z and I did some math and ended up with 950 kg to orbit with conservative balloon tanks, three stages, and vacuum nozzles.
I think an engine thrust uprating would also remove the need for boosters. Merlin basically doubled its thrust from start of development to end of upgrades.
So I don't doubt we can do at least a Mercury type 1400kg minimum viable capsule on a 30 ton pad by adding a tank stretch and engine uprating in addition to vacuum nozzles, balloons tanks, and a third stage.
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We don't have third stages, we don't have vacuum nozzles, we don't have balloon tanks, we don't have an exact weight on the R-4 (so we might not have the spare weight for much of a tank-stretch).
And the winning plan, the plan you are voting for, is pushing ahead with designing an orbital man-rated rocket anyways. That seems like a plan where none of the things you mention will actually get used.
- Location
- the Republic
- Pronouns
- He/They
I don't think we have to wait until we actually have every component potentially needed for man-rated rocketry to do an engineering study on it. If anything, it seems like it'll be helpful to get that out of the way quickly, so we have a better idea of the things we actually need to get it done. If we're going to need an R-5, then we should figure that out sooner than later.
grimely
Twink Death Sufferer
Yeah, this was the order that things were done in real life as well. They thought on what they needed to invent in order to accomplish something, and then they went and invented it.
You mean like how, last turn, we had a big argument amonst our engineers about how to get a man into orbit and this turn a bunch of new projects that might be useful to such a thing appeared?
I wonder how much lighter than Mercury you could drop? For example, if you adopt Vostok-style "just punch out" landing systems, that should shave a fair bit of weight at the cost of, well, being incredibly jank for anything more than a single mission.
24 tons was the figure given, iirc. That said, if it's heavier than that, wonderful; it means more room for optimizations with the existing vehicle.
I don't believe the human-rated rocketry project is designing a specific rocket, but instead doing conceptual studies and the background work to see what's required to keep a person alive in space. If I'm wrong, then I guess we'll all be pleasantly surprised at already having a rocket and capsule ready to go.
Vote closed
Could be worse that nat100 is great though
Construct an R-4 Dawn (117+20=137/120=>17/120) (1 die, -35R)
And launch it (1 die)
Curiosity-class satellite Launch Success, Successful Deployment
Beijing Institute for Chemical Research (CHEM) (157+30=187/450)
New Delhi Institute for Physics (PHYS) (148+30=178/450)
Big Ear [PHYS] (135+74=209/300)
Rudimentary Heat Shielding [MATSCI] (1+1=2/2 turns)
Observation Satellites (1+1=2/4 turns)
Human-rated Rocketry (1+1=2/8 turns)
Nuclear Power Plant Design Studies (0+1=1/8 turns)
Conduct Design Studies (Alternative Launch Systems) [AERO, PHYS] (177+2+37=216/300) (1 die, -5R)
Conduct Materials Research (Phase 4) [MATSCI] (4+131+78=231/350) NAT 100!
University Rocket Competitions
Bothering Councilors (Subturn Initiates!)
-[X] Propagandize for Nuclear Power (100+45+10=155)
-[X] Engineering Job Fair (56+27+10=93/150)
And launch it (1 die)
Curiosity-class satellite Launch Success, Successful Deployment
Beijing Institute for Chemical Research (CHEM) (157+30=187/450)
New Delhi Institute for Physics (PHYS) (148+30=178/450)
Big Ear [PHYS] (135+74=209/300)
Rudimentary Heat Shielding [MATSCI] (1+1=2/2 turns)
Observation Satellites (1+1=2/4 turns)
Human-rated Rocketry (1+1=2/8 turns)
Nuclear Power Plant Design Studies (0+1=1/8 turns)
Conduct Design Studies (Alternative Launch Systems) [AERO, PHYS] (177+2+37=216/300) (1 die, -5R)
Conduct Materials Research (Phase 4) [MATSCI] (4+131+78=231/350) NAT 100!
University Rocket Competitions
Bothering Councilors (Subturn Initiates!)
-[X] Propagandize for Nuclear Power (100+45+10=155)
-[X] Engineering Job Fair (56+27+10=93/150)
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Construct an R-4 (117/120) - (117+17+3) = 120/120+17/120
Launch
Deployment
Beijing Institute for Chemical Research (0/450) - (0+157+30) = 187/450
New Delhi Institute for Physics (0/450) - (0+148+30) = 178/450
Big Ear (0/300) - (0+135+36+38) = 209/300
Rudimentary Heat Shielding ☑☑
Observation Satellites ☑☑◻◻
Human-Rated Rocketry ☑☑◻◻◻◻◻◻
Nuclear Power Plant Design Studies ☑◻◻◻◻◻◻◻
Alternative Launch Systems (177/300) - (177+2+37) = 216/300
Materials Research 4 (4/350) - (4+131+78) = 231/350
University Rocket Competitions ☑
Bothering Councilors ☑
Propagandize for Nuclear Power (100/???) - (100+45+10) = 155/???
Engineering Job Fair (56/150) - (56+ 27+10) = 93/150
Launch
Deployment
Beijing Institute for Chemical Research (0/450) - (0+157+30) = 187/450
New Delhi Institute for Physics (0/450) - (0+148+30) = 178/450
Big Ear (0/300) - (0+135+36+38) = 209/300
Rudimentary Heat Shielding ☑☑
Observation Satellites ☑☑◻◻
Human-Rated Rocketry ☑☑◻◻◻◻◻◻
Nuclear Power Plant Design Studies ☑◻◻◻◻◻◻◻
Alternative Launch Systems (177/300) - (177+2+37) = 216/300
Materials Research 4 (4/350) - (4+131+78) = 231/350
University Rocket Competitions ☑
Bothering Councilors ☑
Propagandize for Nuclear Power (100/???) - (100+45+10) = 155/???
Engineering Job Fair (56/150) - (56+ 27+10) = 93/150
- Location
- [REDACTED]
I'm curious to see what that nat100 on materials science will give us. Seems like we're making good progress our promises, so that's nice. Looks like Big Ear has a good chance to complete next turn, so that'll be resources we can use elsewhere.
- Pronouns
- She/Her
I've put forward Hemp-Epoxy composites, and Hastelloy-N as ideas.
I hope we got Hastelloy-N. 🥺
I want molten salt reactors.
I hope we got Hastelloy-N. 🥺
I want molten salt reactors.
joe6168
Just a humble lurker
- Location
- Michigan, The lower left glove
Waaay safer, which combined with their much higher fuel efficiency and high temps is why they have become so popular in the alternative nuclear design space.
If you want to know more about MSRs I recommend looking up videos by Kirk Sorensen, he tends to focus on the Thorium fuel cycle but that more or less goes hand in hand with Molten Salt Reactors and he's really good at conveying complex ideas in easy to understand ways.
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- Pronouns
- She/Her
Reactor generation numbers are much like jet fighter generation numbers in that they're pretty useless and applied after the fact.
MSRs were discovered and researched quite early, but funding for development collapsed with the end of the Airborne Nuclear Power program, before the limitations of more traditional PWR and BWRs were made more apparent.
Edit: The thorium stuff with regards to MSRs is pure tech journalism crap most of the time. You're still turning it into uranium at the end of the day in the reactor. And there's no advantage to developing a whole new fuel cycle instead of just using uranium off the bat.
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Well they're already melted down so that's one problem solved for safety. The problem is that now you need to build the entire reactor out of a substance that can resist an 800 degree C molten Uranium salt, and it's Anionic partner might be six fluorines. And you need to seperate chemically the fission products from your fuel stream, so you don't just need a reactor and a coolant loop, you also need a chemical scrubber made of this material. And Hastealloy N...isn't it. It's brittle, which could be managed, but when it was used it generated cracking on it's interior salt-touching surfaces. And then there is the concern that Molten Salt Reactors are good at being breeder reactors, the whole point of the thorium cycle. I'm not sure they'll be politically viable in a world scarred by nuclear war because they can be used to make bombs. Even if they don't make bombs, they do require higher enrichment (which again, could make bombs).
Anyways, if the limitations of light-water reactors weren't visible in our 1960s, I doubt we're gonna skip them in a quest for molten salt fuels.
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- Location
- Queensland, Australia
I mean, there's one big advantage which is why I've heard that India is exceedingly interested in developing Thorium Reactors: availability of the fuel material.
Not everyone has uranium ore either locally available or easily obtainable from trade partners willing to sell it to you. If you don't have access to uranium but do have access to thorium deposits (which is supposedly India's situation, at least in regards to 'abundance and thus cost of raw material'), then swapping over to Thorium reactors makes a lot of sense.
EDIT:
Huh. Just looked that up and actually we might end up skipping some of the Light-Water Reactor development for a simple reason: Light-Water Reactors require enriched uranium due to high absorption of neutrons by the hydrogen. Now, I haven't looked into it so I may be completely wrong on this, but apparently Heavy-Water Reactors greatly reduce this issue? So I could actually see a world like this where creating nuclear warhead capable material is a severe concern for everyone rather than just 'anyone who won't like a superpower breathing down their necks' 'jumping' straight to Heavy-Water Reactors despite the increased costs involved with obtaining said Heavy Water just to ensure that as little heavily enriched (thus Weapons-Grade) uranium is needed as possible.
Again: might have misunderstood what I read, and I might be wrong about how Heavy-Water Reactors or other 'advancements' down the nuclear tech-tree might work, so I'd appreciate someone more knowledgeable chipping in on how this may work?
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