Chinese Tusheng Rocket - 130 tonnes to LEO

[K. A. Pital]

Sometimes I'm sad that the Russians never got around to build a Vulkan rocket which would be as close as one could get to the Saturn.

It also would be much more modern than the Saturn, making it a better rocket. Alas, alas. Fingers crossed for the PRC project.

Are there any plans to scale up the Angara project?

None that I'd know of. Angara sucks, and is a sad testament to the state of Russia's space industry.

[Skgoa]

What about building large NERVA type spacecraft in space and maintaining orbital fuel depots to service them ? Is that uneconomical too ?

Since no one has ever come close to doing anything even remotely comparable... its anybody's guess. I can tell you NERVA is never ever ever EVER going to happen, though.

[Seggybop]

What about building large NERVA type spacecraft in space and maintaining orbital fuel depots to service them ? Is that uneconomical too ?

Since no one has ever come close to doing anything even remotely comparable... its anybody's guess. I can tell you NERVA is never ever ever EVER going to happen, though.

NERVA did happen in the past, even though it was never brought all the way. There's a nice test model sitting outside at MSFC. Nuclear power is the only sane, plausible way of accomplishing a lot of missions. Why are you so convinced we won't see it again?

[Sarevok]

Yeah. NERVA is not a crazy idea like Project Orion, it was an established and viable programme with lots experimentation and hard test data. Very powerful (over 500 MW) engines were built and run for extended periods of time. IIRC one of the NERVA testbeds also became one of the most powerful nuclear reactors in terms of power output. Despite the novelty NERVA went surprisingly hitch free and there was strong possibility nuclear reactors were going to fly into space as early as 1970s.

[K. A. Pital]

Orion is not a crazy idea if you launch it from Novaya Zemlya or some other god-forsaken uninhabited place which doesn't care about nuclear explosions. Nuclear power other than that of the Orion type, IIRC, does not offer substantial payload-speed-cost advantages over liquid or solid fuel.

[Pelranius]

Speaking of Orion, would it be a bad idea to launch it from the Empty Quarter or the Sahara (I was thinking about winds carrying the fallout across deserts).

[K. A. Pital]

Speaking of Orion, would it be a bad idea to launch it from the Empty Quarter or the Sahara (I was thinking about winds carrying the fallout across deserts).

This is exactly why I suggested Novaya Zemlya or something in the north of Canada as a better launch point. That, or a forsaken island in the Pacific. However, fat chance of that happening. And bear with me if I'm a bit skeptical. The Chinese need to reach Proton-like rockets first and make them reliable, then go over to larger stuff. Chinese aerospace made big leaps, but their materials science is still struggling in many areas. Now, I hope them being latecomers will help - tech transfer and all that.

[Skgoa]

Anyone who thinks a nuclear powered rocket will be launched any time soon should check himself onto a mental facility. Not only are there stunning security concerns, its also politically impossible.

Yeah. NERVA is not a crazy idea like Project Orion, it was an established and viable programme with lots experimentation and hard test data. Very powerful (over 500 MW) engines were built and run for extended periods of time. IIRC one of the NERVA testbeds also became one of the most powerful nuclear reactors in terms of power output. Despite the novelty NERVA went surprisingly hitch free

... and then all work on it stoped. Huh, strange.

and there was strong possibility nuclear reactors were going to fly into space as early as 1970s.

NERVA is not just a nuclear reactor. If we are talking about nuclear poewered electrical drives (i.e. ion, photon), I would agree to it being viable.

[Sarevok]

Anyone who thinks a nuclear powered rocket will be launched any time soon should check himself onto a mental facility. Not only are there stunning security concerns, its also politically impossible.

We are not talking about nuclear rockets lifting off from Earth's surface. But rather large spacecraft that never lands - think big vessels like the fictional battlestar(yeah I know far fetched example). The benefits of a nuclear drive is that they immensely cut down on complexity of missions to deep space destinations. Without nuclear power humans can barely reach Mars, any further is unthinkable.

... and then all work on it stoped. Huh, strange.

Nothing to do with the problems with nuclear power. NERVA was closed because the space race stopped. There was no need for several hundred tonne spacecraft that could head to Mars and beyond.

NERVA is not just a nuclear reactor. If we are talking about nuclear poewered electrical drives (i.e. ion, photon), I would agree to it being viable.

Nuclear thermal seems to be superior than nuclear electric so far.

[Skgoa]

Anyone who thinks a nuclear powered rocket will be launched any time soon should check himself onto a mental facility. Not only are there stunning security concerns, its also politically impossible.

We are not talking about nuclear rockets lifting off from Earth's surface. But rather large spacecraft that never lands - think big vessels like the fictional battlestar(yeah I know far fetched example).

Oh, I thought we were talking about the viability as an HLV.

... and then all work on it stoped. Huh, strange.

Nothing to do with the problems with nuclear power. NERVA was closed because the space race stopped. There was no need for several hundred tonne spacecraft that could head to Mars and beyond.

Yes. Its the same situation like we have with e.g. supersonic airliners: its possible, its jst doesn't make sense to do it.

NERVA is not just a nuclear reactor. If we are talking about nuclear poewered electrical drives (i.e. ion, photon), I would agree to it being viable.

Nuclear thermal seems to be superior than nuclear electric so far.

Electricity is a nice thing to have on a space ship. And you can use sunlight to safe fuel. And ion drives have been flown very successfully, a big advantage in space engineering.

[PeZook]

Electricity can be generated by using thermocouples to convert some of the reactor's heat into power you need. Converting the thermal output into electricity and then using it in an ion drive is a horrible idea, as you lose a lot of the energy in conversion and requires additional equipment on the spacecraft (the most efficient way to do it is with steam turbines which are of course a ridiculous thing to install on a spaceship )

Ion drives are cool, but not if you want to get somewhere in reasonable time which is kinda important for manned spaceflight. It takes months to get an ion drive probe from LEO to the Moon.

[someone_else]

Just to say something about the current debate: Nuclear reactors of any kind (RTGs included) won't get any support to be used in Earth and Moon orbits. Besides, solar panels have already reached a comparable power-to-mass ratio, so it isn't necessarily a bad thing.

Also, VASIMR claims about being useful with a nuclear reactor are fraud. No known (and not even imagined) reactor can reach the power density they need.

And again, Orion or its technology anyway (nukes in caves that propel stuff ala Verne Gun without significant fallout) would be a pretty nice HLV, with payloads measured in "full moon bases".

They usually then point to the ISS as proof that something like this can be done and point out that ISS was assembled in orbit from 15 modules, each with about 25~ metric tons mass.

Well, the ones I read tend to talk more about how launching more rockets per year means that you can split the infrastructural costs over more launches, and thus have a cheaper rocket to some extent.
Shuttle for example, had to be launched at least 25 times per year to make economic sense, and at least 40-50 times per year to turn a profit.
I'm unable to back it up myself, but this goes more in depth.
Are you able to speculate about how big would be such "cost reduction" for most common rockets?
This is the only focus point to call for more launches, anyone knows the ISS was designed like that to have the Shuttle do something instead of sitting idle (thus to have a reason to eat so much money). And that just like the shuttle, the ISS wasn't built with a specific goal in mind, and it shows.
It could have been designed to be a space shipyard and do something useful instead of just sitting there doing some research now and then.

So lets look at your options for super cheap rockets that aren't bullshit SSTO like Aquarius

Yeah, it was a provocation . Launching 160 rockets (1 ton of payload and 1/3 are failures) is silly no matter how good the number look.
Most papers I read want to send up fuel with Delta IVs or Atlas Vs, anything bad with them?

Atlas V can send 29 tons to LEO at $187 million. Total would be 4 launches, at 748 millions.
Delta IVs should send 20 tons to LEO at "a cost between $140 and $170 millions". Total would be 6 launches and at best $840 millions worst one $ billion.
(numbers come from wikipedia, feel free to call me stupid on them)
Both have a somewhat better reliability record than Falcons.

So that's 23~ metric tons you need to put into orbit to finish all this off. That's another $300m.

Or another Atlas V for around 200 millions.

So, the total sum of your launch costs will be $1.3 billion if you use two Delta IVHs to place the S-IVB, CSM+LEM into orbit, and 14 Falcon 9s to place the fuel into orbit.

Yeah coming close in cost (although I suspect you will slap me), but now only 5 Atlas Vs or 6 Delta IVs are used.

PS -- we haven't even done fuel transfer between two orbiting spacecraft on a large scale yet, and you want to make it central to your entire scheme? Bad Someone_else!

As if they don't have to test each part of their new HLV by torching off 2-5 without accomplishing the mission anyway.
It all depends from what the target is, really. If you want to just get there, then the HLV is the simplest way, but (since I'm a space geek) my goal is finally setting up a permanent human presence in space (not necessarily physical) and government-backed and supported projects suffer from the fact of surviving only because a politician said so.
I think the main goal of any government-backed space endeavor would be setting up infrastructure to make cheaper space access to commercial companies.
And only opening up space to private companies that make profit out of it can give us a true step in space (since even if polititicans change and space is no more in their agenda, if there is profit to be made, there will be someone there anyway).

Launching large science payloads up Pluto's ass is largely irrelevant to me. Once the infrastructure is there and companies make profit out of moving asts around or mining stuff from the Moon or re-purposing old satellites, NASA/ESA/JAXA and others will pay whoever the fuck is already in the business to send their stuff around.

Now, I don't know for sure what is the best way to reach this or even if it is possible at all, (orbital propellant depots and those tethers sound pretty cool though) but that is what must be done if we want to get up there permanently (figuratively and otherwise).

Yes. Our capability to remotely conduct industrial projects is nonexistent

Well, I'm not asking to make an AI controlled self-enlarging chip fab on the Moon. Fuel-production facilities are all is needed for now, and that doesn't require more than a few moon buggies to carry lunar soil around and the thing doing the fuel-production work using solar panels or a RTG as a power source.

And anyway, space suits are bulky, frail and tiring to use, and the gloves aren't able to do fine work.
EVAs are a total pain in the ass to do.
NASA developed Robonaut for this reason and a couple Robonaut 2 have been shipped to the ISS recently to show their worth.
These can be useful due to their humanoid shape to be controlled remotely and do whatever a human can do. Without the pain in the ass of donning a space suit and living in a tin can in a vacuum.

Remotely troubleshooting and fixing problems is incredibly difficult, as was shown with the whole BP fiasco.

You design the stuff to be redundant in the first place, and design it with robotic maintenance in mind, and also have procedures to follow. In other words YOU ARE PREPARED.
BP did decently well, considering they had no preparation whatsoever for a so huge fuckup. THey were clueless for months.

[Sarevok]

Electricity can be generated by using thermocouples to convert some of the reactor's heat into power you need. Converting the thermal output into electricity and then using it in an ion drive is a horrible idea, as you lose a lot of the energy in conversion and requires additional equipment on the spacecraft (the most efficient way to do it is with steam turbines which are of course a ridiculous thing to install on a spaceship )

Indeed. The RTGs on Cassini spacecraft for instance only produce about 600 to 700 watts of electric power. They are also very expensive, requiring plutonium-238 that is no longer produced in US.

RTGs and ion propulsion are good for small probes on long duration missions. But for bigger spacecraft there are better options available.

[Sarevok]

Also, VASIMR claims about being useful with a nuclear reactor are fraud. No known (and not even imagined) reactor can reach the power density they need.

Love to see your source for this. What kind of "power density" are we talking about ?

[dragon]

While having HLV are nice whats really needed is a way to bring the cost per pound lifted to orbit down a lot. As the cost depending on whom it is is around 5000 dollars per pound to orbit. A few companies are promising cutting that in half within a few year which is optistmic.

[erik_t]

Nuclear thermal seems to be superior than nuclear electric so far.

Electricity is a nice thing to have on a space ship. And you can use sunlight to safe fuel. And ion drives have been flown very successfully, a big advantage in space engineering.

The electric power needed by a plausible manned craft is miniscule compared to the drive power required. STS only has a power generation capability of 21kW (36kW surge), and it's only as high as that because of the need for redundant fuel cells. Drawing so little power off of a nuclear reactor is an exercise in pointless capability. Just bring some solar cells along.

[Skgoa]

You could at least have read the other posts in this thread.

[MKSheppard]

What about building large NERVA type spacecraft in space and maintaining orbital fuel depots to service them ? Is that uneconomical too ?

Well. Here's a nice study from 1968 by Boeing on an Advanced Multipurpose Launch Vehicle



It's the big thing on left, Saturn V on right for scale.

It would put about 4 million pounds (1,800~ tonnes) into LEO with each launch using a single 8 million pound thrust toroidal aerospike LOX/LH2 engine in the central stage.

Strapped to the central stage would be no less than TWELVE solid rocket boosters, each one 260 inches in diameter and weiging 1,800 tonnes.

(the other ten SRBs have been omitted from the diagram above for clarity to show the central stage details)

By contrast, the Shuttle's SRBs are about 146" in diameter and weigh only 590 tonnes.

Total liftoff weight for the stack would be 67.9 million pounds; or 30,800 tonnes.

They would have had to build an offshore launching site out of concrete islands about eight to ten miles off shore of Cape Canaveral due to the 120-db limit for noise and 0.4 PSI overpressure limit for exploding rockets on the pad.

Even more problematic would be building the damn thing. While 260" SRMs had been proposed for a lot of other things, like replacing Saturn IBs, the central stage would have been 71.7 feet in diameter.

The Saturn V's S-II was only 33 feet in diameter; and it was a huge problem to get something on that scale put together right for LH2/LOX propellants. And now you want to double that...

By contrast...sticking to something in the Saturn V class of 3,000 ton thrust lets you:

If you are China: You already know something like this can be built, and you can study a lot of 40 year old reports on fabrication of the S-IC, S-II and S-IVB. The technology and precision needed is not a hill of incredible complexity.

If you are America: As above. Plus you already built something like this; and your infrastructure for it was built 40 years ago.

It also offers growth options.

NASA studied strapping on four 156 inch diameter SRBs, each with a 4 million lbf thrust capability to the Saturn V to create the MLV-SAT-V-25(S).

It would have put 494,000 pounds (224 tonnes) into a 100 nautical mile orbit.

I don't doubt that eventually we'll build something similar to AMLLV or SEA DRAGON to make building ever larger things in orbit more economical from a cost perspective; but that is at least 40 years away; and it's grossly oversized for what our needs are now.

Building things out of 100 tonne modules alone allows a dramatic leap in capability and ease of assembly compared to 25 tonne or less modules.

[MKSheppard]

Nuclear power other than that of the Orion type, IIRC, does not offer substantial payload-speed-cost advantages over liquid or solid fuel.

Saturn V Basic could put 66,800 pounds into lunar orbit and land 27,100 pounds onto the moon.
Saturn V/NERVA II could put 91,300 pounds into lunar orbit and land 41,800 pounds onto the moon.

That's a huge difference, essentially allowing you to cut in half pretty much the amount of cargo flights to support a lunar base.

And that was with 1960s NTRs only offering about 800-850 ISP. Modern NTRs that were developed under Project TIMBERWIND for SDI (Star Wars) had 1,000 ISP.

[MKSheppard]

the most efficient way to do it is with steam turbines which are of course a ridiculous thing to install on a spaceship

SNAP-8 would have provided 30 kilowatts electrical power to any spacecraft on a total system weight of 300 pounds. This is due to it using mercury as a fluid to drive a two stage turbine.

SNAP-10A used mercury as a fluid to move heat from the reactor to a thermocoupler. It basically had no moving parts, but weighed 250 pounds and only put out 500 watts electrical.

[Eternal_Freedom]

That is one big-ass rocket there Shep. 1800 tonnes to LEO? Blimey.

Was there ever a projected overall cost/cost per launch on this baby?

[someone_else]

Also, VASIMR claims about being useful with a nuclear reactor are fraud. No known (and not even imagined) reactor can reach the power density they need.

Love to see your source for this. What kind of "power density" are we talking about ?

I was referring to their papers where they design missions using VASIMR to go to Mars in a month.
They assumed nuclear reactors producing 1 kW per kg of reactor.
Soviet's Topaz space nuclear reactors produced 1 kW per 100 kg of reactor.
Prometheus program aimed at reaching 1 kW per 56 kg of reactor.

Even most highly speculative fusion engines I read of don't reach that power density either.

Also Zubrin bitches about it.

Strapped to the central stage would be no less than TWELVE solid rocket boosters, each one 260 inches in diameter and weiging 1,800 tonnes.

Why do I feel scared by so MINDBOGGINGLY HUGE solids? Maybe because if they blow up they eradicate anything in a km or so like a MOAB?

Modern NTRs that were developed under Project TIMBERWIND for SDI (Star Wars) had 1,000 ISP.

They used it for a reusable rocket able to lift up to LEO 100 tons per trip and land again without ludicrously dangerous solids, nor totally ridicolous costs.

Here the paper, page 48 onwards.
They claim that the cost would be less than $100/Kg of payload