Transterrestrial Musings

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Why doesn't NASA strap a bunch of solid rocket boosters together and fire some expendable supplies into orbit. Water and food primarily.

I could be wrong but I'd always thought solid rocket boosters gave more bang for the buck, they are just unsafe because they can't be turned off. Well that load of water (to be used as fuel or whatever once up) doesn't care about the safety and if it crashes it costs money but a little extra humidity in Florida will hardly be noticed.

If water is too annoying as fuel we could send up Kerosine or something less environmentally friendly but more directly useful as fuel.

I mean wouldn't the equations start to change if whatever vessel we used could tank up in near Earth orbit? Couldn't we then dump heat shields and start to use engines to break into orbit a bit more safely? Couldn't we then not worry about lifting extra fuel up with whatever mission we have and just worry about getting the biggest capsule/ship we can on our launch platform.

Couldn't NASA sell the fuel to private companies to help build a sort of beachhead to promote expansion.

I must be missing something because nobody else talks about this sort of thing.

Posted by rjschwarz at January 3, 2006 08:42 AM

For that matter why not fill the shuttle up with a load of kerosine and send it up unmanned. If it blows so be it, no one is hurt and NASA's reputation is unstained. If it doesn't we've got the first stage of our orbital gas station with nearly zero additional engineering.

Posted by rjschwarz at January 3, 2006 08:49 AM

I've been intrigued by this concept for several years. I would like to see it called Mars Lego(tm). :)

I once completely bought in to Zubrin's wi^H^H bigger is better mantra with Mars Direct, especially in light of the horrid ISS construction. But it always seemed to me that if you didn't truly build a spacecraft in orbit, just docked modules together, some of which were engines with self-contained fuel tanks, that you might be able to have your cake and eat it too.

The personnel cost vs. the weight cost is a very interesting issue, and I think that Rutan proved a major point when he used a command center consisting of under a dozen guys with laptops. I think that the people cost of existing craft is terribly underreported.

Posted by Big D at January 3, 2006 08:58 AM

I think dry launch makes far more sense form an EELV perspective than the Lego concept advocated in the TSR article.

Dry launch means fewer docking interfaces required and does not overly size limit your planetary landers.

Still, other HLLV considerations not in play in the early 70's with the Saturn V are that per pound, the HLLV will be no more per pound than th ecurrent shuttle system and it has provenn sustainable for 30 years. To argue that an HLLV system is not sustainable becuse of Apollo is too simplistic IMO. Post-Hoc, Proctor-Hoc.

With the Shuttle, we essentially traded a capable first generation HLLV (Saturn V) for a handicapped second generation HLLV in the Orbiter handicapped Shuttle stack.

Another potential HLLV customer is the Military. In the early 70's there was no demand for very heavy .mil space platforms. Today, we are contemplating laser satelites challenge the lifting limits of the current heavy ELLV's.

An HLLV removes this constraint. The 125 ton HLLV could orbit two Abrams M-1 tanks. With that lavel of capability, you could actually add passive protection like heavy armor plating that is simply impractical at the current time.

Posted by Mike Puckett at January 3, 2006 09:50 AM

Dry launch is a great idea. But we need more launch pads to sortie a large number of missions.

Delta IVH has only one pad in Florida and DoD missions launch from there at times as well. Scheduling 6 EELVs into DoD needs for that one pad will be tricky. Build a new pad? Then costs start to mount, just like with shuttle derived. Beside Delta IVH ain't cheap.

= = =

Now, if we were buying Protons at $50 - $75 million each ($1500 per pound to LEO) or if Boeing would sell Delta IVH for $100 million a piece. . .

Posted by Bill White at January 3, 2006 11:05 AM

It looks like he may have forgotten to add in several additional launches of astronauts to assemble the components he launched with his six boosters. If you need 2 assembly missions, then he needs 8 launches vs. 1 for the HLLV. (8 launches (or even 6) in 6 months is obviously far higher than NASA's recent launch rate for the shuttle.) You then have an assembled but *untested* system in orbit. All together, his scenario sounds more complex, riskier, more failure prone, and might ultimately be more expensive than an HLLV approach.

The need for an HLLV is a chicken-and-egg situation to me. He sees no need for an HLLV on the horizon. True, because no one designs a payload for a nonexistent launch vehicle. Instead, the lack of an HLLV has forced us to go to extremes to downsize payloads and compromise the paths that probes take to their destinations. (Cassini to Saturn via the moon, Venus, Earth and Jupiter, for example, taking many more years of flight time than it would have had a larger booster been available. Or compare Skylab-sized modules to the shuttle-cargo-bay-limited modules of the ISS.) It means that the shuttle and ISS provide essentially no radiation protection for astronauts, because we can't lift the needed mass.

When I had an SUV, I could do things that I cannot do at all now that I have a sedan, and that I can only accomplish by enlisting a friend who *does* have an appropriate vehicle, or by other, extra-cost methods.

If we had an HLLV, missions would be designed differently, could be done differently, done bigger (more redundancy, more fuel for orbit changes, more and bigger instruments), and done better than now. Just my opinion, but I haven't read anything that convinces me otherwise, including this article.

Posted by lmg at January 3, 2006 11:12 AM

Of course, we should mention political reality, which is the driving factor is this decision:
Largely maintain the existing standing army of personnel and aerospace firms involved with the shuttle.

The economic reality is largely in agreement with Rand and Grant. The cost of building two new boosters (and yes, they are new) is estimated at something like 5 billion. It will grow to be much higher as delays stretch the budget.

Designing constellation components to fit on existing boosters would create a market for 10 - 50 launches per year. Much of the mass would be fuel, and could be launched on any booster allowing NASA to source multiple suppliers.

Why is this good?
1) prevents program shutdown due to single type of booster failure
2) lowers booster cost due to competition
3) lowers booster cost due to economies of scale
4) eliminates the cost of developing a new launcher

While politically very unlikely one could imagine using Sea Launch, the Cape, Russia, Guiana largely eliminating the launch pad capacity issue. A reasonable design for a orbiting fuel depot would solve the need for concurrent launches while providing useful infrastructure for interplanetary missions.

Posted by Fred K at January 3, 2006 11:54 AM

> It looks like he may have forgotten to add in several additional launches
> of astronauts to assemble the components he launched with his six boosters.

Which seems to be the real underlying argument: we need HLLV because it minimizes the number of people we "have" to launch into space. It isn't surprising that the current architecture came from the Planetary Society, a long-time opponent of human spaceflight (except at the trivial "let's send a couple PhDs to Mars to collect rocks" level).

> If we had an HLLV, missions would be designed differently, could be
> done differently, done bigger (more redundancy, more fuel for orbit changes, more and bigger instruments),

In an imaginary world, with an infinite supply of money. In the real world, where money is not infinite, you get fewer missions, less redundancy, less fuel for orbit changes -- the same thing NASA's gotten for 40 years.

What makes you think this "new" approach is "different"? Do you think NASA has never built an HLLV (Saturn, Shuttle) before?

Posted by at January 3, 2006 12:00 PM

Additional launches of astronauts to do assembly?

That's kinda half the point of this concept. You build your modules on the ground so that they dock together in space. Think Lego. Not balsa airplane model, not ship in a bottle, but Lego. You dock simple modules together that don't have to be interconnected in a zillion different ways (redundant ethernet and power lines connected through the docking adapter is enough) and fly. You don't weld, bolt, paint, or bailing wire anything in orbit.

Yes, it won't be as mass-efficient (the craft, not just the boosters) as a HLLV launching a big craft. But if it requires half the engineer-hours to build, and most of the difference in mass is fuel... fuel's cheap. Engineers ain't.

Posted by Big D at January 3, 2006 01:37 PM

a couple of 20,000 ton Orion's would go a long way to establishing a beach head.
If only some people could get over the "radiation boogyman"

Posted by Harley W Daugherty at January 3, 2006 04:40 PM

Ironically, Grant Bonin's conclusion (six EELV launches for each segment of Mars Direct) isn't too different from Robert Zubrin's "Athena" proposal, which used six launches (four Proton, two Shuttle) to assemble a Mars flyby spacecraft.

I like the orbital assembly idea as long as the operation is automated. Automated assembly shouldn't be hard; the Russians did it with Mir, but it was largely ignored for ISS.

The only challenge now is using EELV's to meet the necessary flight rate. With the EELV market down but the Air Force committed to maintaining both production lines, this does not look like a big problem either.

Posted by Chair Force Engineer at January 3, 2006 05:16 PM

> I like the orbital assembly idea as long as the operation is automated.
> Automated assembly shouldn't be hard the Russians did it with Mir

Automated rovers shouldn't be too hard, either. NASA did it with Pathfinder.

What is the point of spending billions of dollars to build automated outposts that no one but R2D2 and C3PO get to visit?

Posted by Edward Wright at January 3, 2006 05:37 PM

If only some people could get over the "radiation boogyman"

Might as well wish for magic swans to lift us to heaven on feathery wing; it ain't gonna happen.

What is the point of spending billions of dollars to build automated outposts that no one but R2D2 and C3PO get to visit?

Ahhhh - it's cost effective, see? And when someone else arrives to strip them for salvage we can pretend it's a gift to them.

Posted by Brian at January 3, 2006 06:39 PM

I think that the point that going with multiple launches of EELVs have a lot of hidden costs (as well as not so hidden risks.) Besides, the idea of a launch vehicle that was created with heavy DOD subsidies is in any way "commercial" is dubious, in my view.

There are ways for commercial space to get in on the VSE and even improve it, but not by trying to get NASA to scrap it's current approach. It's certainly not politically viable and probibly not economically or technically viable either.

Posted by Mark R. Whittington at January 3, 2006 09:16 PM

If NASA goes with an HLLV and t/Space and/or SpaceDev and/or Musk succeed with their light launchers then NASA can buy the little guys off the shelf and NASA is NOT in competition for crew transfer or fuel slogging to LEO.

Mike Griffin is already on record that he wants a private sector fuel depot to fuel his HLLV Mars ship. If NASA does NOT build medium lift (EELV class) that leaves a huge niche for alt-space to fill. SpaceX can carry fuel in a thousand tiny bottles perhaps cheaper than NASA and Gump can ferry the crew up to a robust Mars capable exploration vessel.

And, if alt-space drops the ball, Griffin still has CEV+CLV.

Posted by Bill White at January 3, 2006 09:42 PM

Do you imagine if we had an operational Saturn V today we wouldn't use it for both the Moon and Mars?

But we can do without and probably will at first. I think the cost of going to the Moon is going to just waste another generation of opportunity. It's no different than the ISS or the shuttle program.

Talking about economies of scale and flight rates will do almost nothing (no matter how good the math looks on paper.) We need people dying on the surface of a world they are trying to make habitable. I guarantee lots of volunteers.

Going to the Moon is the equivalent of putting an tent in your backyard.

Musk (my hero) claims his Merlin engines are more powerful than the F1, but I see 150,000lbs for the F1 vs. 77,000lbs for the Merlin. Somehow I don't think he'll ever need the standing army NASA has to double his capability.

Arguments about refueling depots and in orbit assembly are a waste of time because they apply regardless of the mass sent to orbit.

Even the standing army argument is irrelevant, because it's too large regardless of the class of vehicle.

Mars Direct was not just about rockets... it was about bricks and gardens and economies. It was about a people being more than we are today. Leaving the nest for real this time. All those little rockets will be good for the real settlers, steerage class laborers and such. It's going to take thousands of people to get a colony rolling. Most will be born there.

Posted by ken anthony at January 3, 2006 10:01 PM

A few technical notes

The planned NASA development budget is 5 billion dollars for the medium class 'stick' Crew Launch Vehicle and 10 billion dollars for the shuttle derived Heavy Launch Vehicle. So rather than using off the shelf medium launch vehicles NASA will spend 15 billion dollars to create two new launch vehicles. Imagine the LEO payload that could be bought for 15 billion dollars.

Then there is the supposedly easy and simple Mars mission using the HLV. No one commenting here has noted that the current plan involves three vehicles, 2 x HLV + 1 x CLV, using EOR to assemble the manned Mars Transfer Vehicle in LEO. And that many EOR is despite the fact the MTV uses Nuclear Thermal Rockets for propulsion.

If the Bonin Mars plan of EOR of 6 x MLV could use NTR too, then Bonin could use only 4 X MLV to assemble his Mars mission. I don't see how 3 X EOR is vastly superior to 4 X EOR. The HLV fans who use criticism of orbital assembly to justify the HLV are not being fair.

Posted by Brad at January 4, 2006 05:59 AM

Note that it is the Merlin 2, which Musk is putting a lot of money into, that is more powerful than the F1, not the Merlin.

That said, if the modules for the spacecraft are designed for launch on EELV-class rockets instead of a HLLV, then it opens the door for Falcon 9 or any other rockets of that size. If the spacecraft is designed for a HLLV (see Zubrin's tuna cans, for example), then it can't be launched on anything but a HLLV and we're hosed for alternatives for quite some time, because other than Musk's hints at a distant project there isn't really anything on the commercial space radar.

Posted by Big D at January 4, 2006 05:59 AM

One other thing

Elon Musk never claimed his Merlin rocket engine had F-1 class thrust, since the F-1 had 1.5 million pounds of thrust compared to the Merlins original 75,000 lbs, such a comparison is absurd.

What Musk did claim is that he plans to develop a new rocket engine that would be more powerful than any currently in use. Musk said his new engine would be in the F-1 class.

Posted by Brad at January 4, 2006 06:06 AM

Fred K and Bill are making very relevent points that the 'anti-HLLV' argument continually ignores. Political reality, is not merely a matter of making Congressmen happy about spending money in their districts--in a more general sense, it is also about giving the (rather small, pea-sized) imaginations of our political leaders something concrete to grasp and fund and make soundbite quips about.

The corollory to this--that law makers want to see something physically drawn up for those billions--is that if NASA declares now that it is going to focus on MLVs, that means NASA is going to have to decide much earlier than it wants to who to give those launches to, and all the ugly details thereof. That will only perpetuate the stagnation that many who favor MLVs claim to want to avoid.

The reality is that no matter what launch system NASA chooses to go with, the total number of launches will never be enough to make a particular launcher profitable. Only the commercial sector can really pull that off.

I think it's likely NASA hopes to stay out of the fray, pulling a sort of rope-a-dope to allow the current commercial launch market to develop for a few years before imposing a huge distortion that will perpetuate the current situation of state-funded commercial launchers.

Posted by cuddihy at January 4, 2006 10:08 AM

> Political reality, is not merely a matter of making Congressmen happy
> about spending money in their districts--in a more general sense, it
> is also about giving the (rather small, pea-sized) imaginations of
> our political leaders something concrete to grasp and fund and make
> soundbite quips about.

If you have so much contempt for political leaders, why are you willing to let those same politicians build another national space transportation system?

Sen. Sam Brownback, Re. Dana Rohrabacher, former Rep. Newt Gingrich, and former Presidential candidate Steve Forbes are just a few of the politicians who have proposed large prizes for private manned space programs, tax incentives for new space businesses, etc.

If "pea-sized" imaginations can come up with innovative ideas like that, what does that say about an agency that can't come up with anything more original than "Apollo on Steroids"?

Posted by Edward Wright at January 4, 2006 01:42 PM

I always find it rather strange that SpaceX gets used as an argument to why one should use smaller rockets. If i remember well, it's a dream of Musk to go to mars and he has said he wants to build HLV's which could be used to go to mars. He doesn't talk about using 10 Falcon 9's to go to mars. Griffin uses the same argument to justify HLV's, he says maybe you don't need to have an HLV to go the moon but you need one to go to mars. And the VSE clearly sets going to mars as a goal.

Posted by Problem at January 5, 2006 07:54 AM

What's the min size pressure vessel that has to be lifted to LEO (high LEO?) for a Mars surface station in one piece? 50 t?
Do a dozen launches last too long and there's propellant boiloff?

What exactly are the factual reasons cited for needing a HLV for a Mars mission?

Posted by meiza at January 5, 2006 10:16 AM

Good question, meiza. Looking at "The Case for Mars" it seems to boil down to Direct Launch. Going to LEO and then throwing yourself at the target. Or as Bob said:

"But, if a manned Mars mission can be done by direct launch, then we can do it. Get rid of the spaceships and spaceports, and a human mission to Mars moves from the 'parallel universe' of The Future into our universe. If we can do it by direct launch, then 90% of everything we need to send humans to Mars is available now."

The thing is, for a sustained space future we do need orbital facilities, and places where people can do materials science work and bio-pharma work and combustion and ceramics and optics work and more. A processing place for free-flyer platforms, or missions to GEO (I'm also thinking of L-1 facilities), or refueling, or what have you.

Do you need to know the specifics of how I intend to make vacuum spheres to sell to the good citizens of this world for a fair price? No, as a consumer you just need to know that thanks to Lunadyne LLC you could hold a bit of the vacuum of space in your hands (someday...maybe...). Future editions will include Lunar regolith and teensy tiny feather and hammer replicas. There'll also be educational and industrial lines of large hard-vac tubes. (I bet they'd make nasty bullets too. I hate this dual-use stuff)

We can't do that sort of thing with what we've got now and I wouldn't be able to do it with what we're going to get from NASA. If we do things a lot differently I could probably be doing it in a few years.

Direct launch from LEO is not necessarily the best way to get to all destinations in space. If you start looking at potential traffic flows driven by economic interest (GEO, EML-1, Interplanetary Superhighways, Moon, asteroids, Mars), then LEO Direct is a pretty pith-poor way to go about it. Change the architecture a bit, and things start overlapping in a big way. It's all in how you look at the question.

Posted by ken murphy at January 5, 2006 06:40 PM

Not being a rocket scientist, I probably misunderstood this at the spacex site...

"With a vacuum specific impulse of 304s, Merlin is the highest performance gas generator cycle kerosene engine ever built, exceeding the Boeing Delta II main engine, the Lockheed Atlas II main engine and the Saturn V F-1."

Personally, I'd like to see a private company waiting for NASA when they get there. I'd also like to see them stop wasting money and offer prizes instead. But Griffin is a government engineer, and acts like a government adminstrator, which leaves us with a shuttle derived vehicle.

One thing I think might happen soon is colonization may become a matter of national prestige. I think we should send a return vehicle to Mars, but not necessarily use them. I think the trips should be one way as colonists rather than round trips as flag planters. Once a nation has a colony establish, how long before other nations are going to want to be part of the act?

It is my belief that a positive economic reality, gainful trade even, depends on permanent, self sustaining colonies, which we can do within the next 10 years starting now. NASA can't be the same organization in ten years. Perhaps we have a window for redirecting it now (but having worked in government, I don't see how it can be redirected much???) I see Griffin saying some positive things within the reality of options he has available.

In the 60's we didn't go to the moon to colonize, nor would it have been a good idea then. I believe Mars represent the most reasonable choice for colonization now and we shouldn't let anything distract from that. Let me win a big lottery and I'd certainly buy a ticket (well, I'd need two tickets. I'm a big guy!)

Posted by ken anthony at January 5, 2006 11:16 PM

Well, I don't know what that means, since the F-1 had a specific impulse of 304 seconds as well, so it's not better in that regard--it's the same.

Posted by Rand Simberg at January 6, 2006 05:21 AM

Besides, Isp has more to do with gas mileage than thrust, which is what people usually assume that you're talking about when you say "powerful" in regards to rockets.

As far as colonization goes... I don't think there's enough support to turn astronauts into colonists from the get-go. I've seen that idea pop up a number of times, as it really saves weight when you don't have to have a return vehicle.

However, I think it would be a really good idea to consider landing each mission next to each other (and putting wheels on everything), building a Mars (or moon) base as you go. You'd need extremely reliable long-endurance rovers (basically mini-habs) to get the crews away from their well-trod areas, but I think the benefit of being able to re-use so much hardware and spare supplies and run extended missions like ongoing greenhouses would be worth it.

Posted by Big D at January 6, 2006 07:50 AM

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