Zubrin on Moon, then Mars - Three essays, one link

BWhite · 2005-03-18 21:43:34

Michael Bloxham gets :up: :up:

for a most righteous rant. Well done!

GCNRevenger · 2005-03-18 22:36:43

Righteous rant? Oh hardly...

"Reduce the crew size from 4 to 3. Whoopee, all problems solved! In addition, smaller less critical components of the Mars Direct hardware could be launched separately on an MLV (or an additional launch of an SDV?)."

*Bzzz* Nope. MarsDirect already has a problem of limited manhours per sortie each given the investment. The marginal cost of increasing the crew is a much better deal infact. Reducing the crew size isn't going to make up for the reactor mass is 400% too low, the rover is impossibly light, and that sort of thing either.

"Crew psychological health is way over-rated"

*Bzzz* Wrong again. Even astronauts on Mir have had documented psychological problems that have affected their productivity and safety, and this simply cannot be assumed to be trivial. It will be even worse since the astronauts will have no direct contact to anyone Earthside for about 2.5yrs. Nor will they have internet access, and nor will they have stars over their heads... it will just be a rarely-changing blackness through the small windows in their never-changing claustraphobic tin can.

I also strongly side with the camp of psychiatrists that reccomend large CONTIGUOUS spaces, not the collection of closets that Zubrin wants, and not the extremely cramped ERV. In this respect, MarsDirect is simply unworkable, a single-deck HAB or the <6m ERV is just unacceptable.

NASA has also found that a six-man crew should be the absolute minimum to help the crew stay glued together mentally for long periods... especially given their tough workload. Mental health is a problem, you are deluding yourself if you think otherwise.

"I have yet to see a mission plan that is more capable than Mars Direct."

Okay, how about NASA DRM? It starts with a HAB module more then double the size of MarsDirect, six-man crew standard, lots of payload on the acent vehicle payload, and no super-cramped ERV. The system is capable of delivering far more payload direct to Mars, and has considerable headroom for the future.

The ERV vehicle also could be recycled relativly easily, and with reuseable MAVs, you can radically reduce the number of launches needed for each crew rotation. If the ERV were used in place of the HAB module, you would have a basically reuseable system except for the TMI stage... DRM has more inherint capability, much saner mass figures, and a future upgrade path.

MarsDirect does not, it cannot evolve to be something better, it is a dead-end... Bob is so bent on reaching Mars, he would sell us out in his rush to get there and sacrifice after MarsDirect...

Oh, and you can't launch MarsDirect in pieces to assemble in orbit either, as the Ares model Zubrin has in mind relies on not entering Earth orbit to make it efficent enough.

"Damnit! I am so sick of hearing this! Why is it so damn critical SDV must be 'cheap enough to fly'? Is the space shuttle cheap enought to fly? Was the Saturn V cheap enough to fly? What is cheap enough to fly?"

Okay, let me explain this slowly for you, and maybe it will sink into your Zubrin-infatuated brain...

NASA has a pretty well limited budget. It is probobly not ever going to see a major increase given our economic environment. This is really a zero-sum game, it just isn't realistic to plan on there being a major Mars windfall.

So, "cheap enough" means not spending so much money on getting there that you have no money to do anything when you do get there, and have enough to start work on what to do after that. Simple enough?

Right now, the Space Shuttle costs about $4.3Bn per year. This cost is so high it will obviously strangle VSE or any Mars expeditions. You might be able to get there, but you wouldn't ever do much... Given NASA's small $15Bn budget, of which a little over half is available to spend on spaceflight, the remaining breadcrumbs are not enough.

I would estimate that we would have to cut the SDV budget down to one half of the Shuttle budget down to ~$2.0-2.5Bn yearly for lets say five or six flights... So to answer you question, no Shuttle is not cheap enough to fly, and back in the Apollo days (where price was no almost object) neither was Saturn-V... NASA was already looking into more efficent rockets before Apollo ended. You can do alot of things for $1-2Bn a year, and we just can't let it get sucked up by SDV.

"Yes, and I don't blame him 'cause its the damn truth."

Ummm no. Zubrin says things that are at best dishonest and deceptive, and at worst, outright lies. If you support what he says about EELV, then you are too.

The most obvious example is the straw-man or outright lie that EELVs would have to be launched rapidly (inside of a month) to accomplish the mission. Also a flat out deception, that EELV cannot be upgraded more then ~10%, which they clearly can be.

And having liars for Mars advocates or advocates willing to sell out the future for the rush-to-red-dust, isn't going to help the cause one bit.

Michael Bloxham · 2005-03-19 00:10:04

So what you are advocating is an EELV-based lunar program, then develop a clean-sheet HLLV, then top it all off with a DRM based (crew of six) Mars program, with some reusability thrown in? It's starting to look pretty complicated (read expensive) to me.

Yeah okay, you could free up a lot by firing the shuttle army. But I have to argue: Can we really kill The Army? In my opinion, the only sensible option would be to assimilate The Army into a much broader effort. I doubt NASA will ever be in the position (political or otherwise) to simply fire them (again, if that was the case, wouldn't they then be immediately re-hired to work on other projects?). NASA simply cannot do without them. Some may continue work on an SDV, others will be re-assigned to CEV and other projects.

The Army is NASA.

Shall we kill NASA? I'm all for it!

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Edit: Sorry, I have to respond directly to some of your statements.

"MarsDirect already has a problem of limited manhours per sortie each given the investment. The marginal cost of increasing the crew is a much better deal infact. Reducing the crew size isn't going to make up for the reactor mass is 400% too low, the rover is impossibly light, and that sort of thing either."

I too would like to see a bigger crew size, but only if the cost really was marginal, and its not (Last time I checked DRM was nearly twice as expensive as MD, both for development and recurring missions). But four is good enough for me, and we could still use MLV's to deliver smaller bits and pieces integral to the mission, if need be.

"It will be even worse since the astronauts will have no direct contact to anyone Earthside for about 2.5yrs. Nor will they have internet access, and nor will they have stars over their heads... it will just be a rarely-changing blackness through the small windows in their never-changing claustraphobic tin can."

Whatever happened to the days of posted letters? Actually, replying to your post has taken longer than the time delay expected from the marsian surface to the earth (you could imagine I'm already there, yippee). Internet access will be limited, due to the delay, but there will be workarounds. As far as the blackness of space? That's a silly conspiracy; short exposure film created that one. You can see stars in space, I assure you. But nevermind, I'm sure they'll survive.

"I also strongly side with the camp of psychiatrists that reccomend large CONTIGUOUS spaces, not the collection of closets that Zubrin wants, and not the extremely cramped ERV. In this respect, MarsDirect is simply unworkable, a single-deck HAB or the <6m ERV is just unacceptable."

DRM hab is not much bigger, considering the larger crew size, and there's no artificial gravity, a huge disadvantage both to mental and physical health.

"Zubrin says things that are at best dishonest and deceptive, and at worst, outright lies. If you support what he says about EELV, then you are too."

I am at best, unimformed, . But what I don't understand is that on one hand you advocate EELV's all the way, but then concede an HLV is needed for a 6-crew mars mission? ???

Ad Astra · 2005-03-19 00:29:30

Cull "The Army," don't kill it.

People who worked on the orbiter could easily be reassigned to either the CEV or the new elements that would be going into SDV. People who worked with systems like ailerons and landing gear will probably be cut, while propulsion and life support would largely stay.

The problem is one of automation. The shuttle facilities are very man-intensive; EELV operations are more streamlined because robots are doing many of the functions that are done with people on the shuttle. Starting with 60's era Apollo-shuttle facilities is a disadvantage in this important aspect.

If any of the prime contractors really wants to do an SDV, they should have to put forward some revolutionary ideas for streamlining the manufacturing and processing of the vehicle.

GCNRevenger · 2005-03-19 00:33:33

I would actually be quite happy with an SDV-centric Lunar strategy, it does apear more efficent, but I can't support it more then EELV unless I have better assurances that SDV won't strangle VSE. Since EELV is basically a known, but SDV is an unknown (or even likly unacceptable if The Army is largely retained), then EELV is the only choice... As nice as clean-sheet would be, its high development price tag is probobly unacceptable for the near/mid future.

The flexibility offerd by EELV also sweetens its pitch, if you only want to send supplies to the Moon or launch large probes, and the military could buy into the program for its needs and drive down unit costs too.

Again, clean-sheet would offer the best of both worlds, with optional manned, medium, and heavy launch with the same rocket... But I expect its price would start around $6-7Bn and run up to $10Bn easily.

The Shuttle Army consumes almost four billion ($4Bn) a year... it just has to be trimmed down. If NASA management can't cut this by about half (by outright layoffs, reassigning to non-launch jobs, etc), then yes, the only option is to lay them off and start over by executive order.

Michael Bloxham · 2005-03-19 01:14:44

Y'know, sometimes I wish Bush had never made his speech. As disloyal as that may seem, I really can't help but wonder what could have been... Maybe it would have been better for NASA to come to it's own senses, without some un-informed political figures (sorry Mr. President) misguidance. I can't help but wonder if a clean-sheet super economical HLLV might have been a natural progression for NASA.

Well, okay... maybe not. But I think Bush could have done better, atleast.

GCNRevenger · 2005-03-19 01:34:27

I think that since MarsDirect is impractical with even four crew, that it would wind up being much more expensive trying to make it work sort-of well, and probobly wind up losing alot of capability and safety in the process. Zubrin also assumes some absurd "competition" to radically lower costs, which is insane since nobody would put the billions needed to enter the contest without the promise of reward.

Using EELV to help shore up the rediculously low mass estimates for MarsDirect is one of these things to vainly try and save it. Docking in orbit would cause a performance hit for Ares, since it is tailored for escape velocity shots and not orbital insertion. Also, you will require at least two EELV launches, one for the supplimental payload and one for the crew (since you want to minimize crew space exposure), which also means more orbital operations too.

This also kills the artifical gravity idea, since it relies on spinning counter to the spent TMI/2nd stage. The fuel for the stage probobly won't store long enough in LEO to fly two EELVs, dock, checkout and only then depart...

Yes NASA DRM is more expensive, but it is also more capable, and capable of operating for much less money later with reuseability options. Pay extra now, save money later and get a better ship.

I am not too worried about the physical health during transit, I think that we have that pretty well coverd. The extra contiguous volume offerd by DRM on both legs of the mission makes a big difference in addition to having considerably more volume per-crewmen.

Remember, you also get alot more use of the space you have with DRM since the airlock/suit room/bulk storage is in a seperate "basement" deck. I also bet a "cockpit coupola" in the nose would fit, which would free up even more space. DRM uses what it has more efficently then MD.
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I will have to disagree with you about the "letters from home" and "look at the pretty stars" arguments. We can't keep astronauts from getting depressed reliably even in Earth orbit where home is almost a phone call away. The view out the window will get pretty boring too, since it won't change much during the mission.
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I am for using EELV+ for the Moon since it is a proven and available option that we can rely on being capable and affordable, with the added bennefit of flexibility not offerd by SDV nor unmodified EELV, and have relativly low development costs (which are crucial to keep low until NASA gets on its feet again).

I think that a trip to Mars will be long enough from a Lunar return that there will be time to develop a new heavy lift launcher to get there without too much trouble... we could make it replace the EELV+ and might be good for Lunar heavy mining gear too.

I fear SDV because NASA will be tempted to "find a job" for the old Shuttle engineers, the same engineers that have kept NASA so close to bankruptsy that it can't do anything but go in circles. If NASA can't deal with them, then NASA is doomed.

PS: "I am at best, unimformed"... And now you are. No more excuses to take Bob's word on blind faith anymore... for anything perhaps.

Michael Bloxham · 2005-03-19 03:46:29

Using EELV to help shore up the rediculously low mass estimates for MarsDirect is one of these things to vainly try and save it. Docking in orbit would cause a performance hit for Ares, since it is tailored for escape velocity shots and not orbital insertion. Also, you will require at least two EELV launches, one for the supplimental payload and one for the crew (since you want to minimize crew space exposure), which also means more orbital operations too.

I don't propose shipping mission critical components on MLV's, just bits and bobs like science equipment, rovers, spares, and extra supplies. It may not be much, but anything helps, right? This way, the core Mars Direct architecture stays exactly as it is.

Delivering extra equipment seperately to the surface might also assist in the productiveness of the crew: I can imagine long-range rovers, mining and ISRU equipment, large inflatable greenhouses, and miscellaneous tools as potential cargoes.

I'm a Mars Direct/SDV-hugger only because I find it a settleable compromise between idealistic visions and realistic expectations. But I also beleive we will go nowhere if we cannot compromise on a plan, even if it means that the plan itself is compromised.

GCNRevenger · 2005-03-19 08:16:09

No way Michael, MarsDirect is fundimentally unfixable.

"It may not be much, but anything helps, right?"

No it doesn't. First off, the mass of these "non mission critical" items are a small part of the total mass, and removing them won't make either MarsDirect vehicle light enough for sane mass budgets. The "non critical" mass of the ERV is basically zero, and that is the biggest problem area.

You would also have to build landers and aerobrake shields and upgraded EELVs for these supplies, and trust that you can get them all to fall within walking distance of the HAB, if you intend to fly the rovers seperatly. Also, if the HAB or lander payload lands off-course and the crew can't walk to the ERV, you won't reliably have a rover to get the crew to the ERV, and you couldn't send a new one from Earth for years.

You can't bring down the mass enough for the major componets (the ERV especially) by just throwing stuff out. It would change the mission design way too much, and you would lose all the bennefits of MarsDirect. This idea will greatly increase the cost and reduce the reliability of the mission.

The solution is really very simple, but it is the one thing that Bob will not hear anything of it... don't go directly to Mars. Trying to pack an entire Mars mission into only two HLLV shots is just a very bad idea. Bob is simply wrong.
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The SDV issue is really also pretty simple. NASA has somewhere below $10Bn a year to work with, probobly closer to $8.0-9.0Bn, that it can realisticly spend on spaceflight. NASA isn't going to get any big funding increase for the forseeable future, so everything NASA does has to be done within this budget.

Shuttle today costs a bit over $4.3Bn to fly, which would leave NASA with only $4-5Bn (maybe $6Bn) to do everything else. To build CEVs, to build EDS stages, to build LSAMs, to build Lunar telescopes, to build space nuclear reactors, build Lunar habitats, build Lunar ISRU plants, reuseable landers, PGM extraction smelters, LLO fuel depots, reuseable tugs, aerobrake shield technology, super space suits, ballistic hoppers, new rovers...

And for the future, developing HLLV for Mars, the modified reactor, and the Sabatier ISRU plant, the heavier acent vehicle, the bigger HAB, the NTR engines & TMI stage, the big storable ERV TEI stage, the massive lander, the decent gear, the new Mars heavy rover, water drilling/extraction gear, extensive life sciences package(s), water extraction plant, reuseable MAV, UV/cold-proof plastic green houses, polymer plant & machine shop, perhaps a future LMO fuel depot.

And if we are ready to move industrially into space, start socking away some money to build the $15+Bn Shuttle-II, so that we finally can get into space without having to throw away the vehicle we used to get there... and space-to-Earth solar power systems should also get started.

This the future, the next 40 years after Shuttle/ISS, the things that we will want. NASA simply can't do all this for a measly $3.7Bn a year. I figure that NASA would need a bit less then double this amount. Therefore, whatever rocket we use, it just can't cost more then ~$2.0-2.5Bn a year to operate. If you cannot promise SDV can do this, then SDV is too expensive.

Think about it... if you save $1.5Bn a year for 40 years, that really adds up, $60Bn dollars! That money is vital to ensure that NASA doesn't get stuck just kicking Moon rocks around a few times a year and calling it good.

NASA has the money to do all this and more... it just can't afford to let it all go into the black hole of the Shuttle Army. Easy enough?

GCNRevenger · 2005-03-19 09:41:30

I have a general strategy in mind... Divide the budget into basically three pieces to:

A: Pay to develop and operate expendable and expandable means of getting to LEO/Moon/Mars/etc for minimum development cost to reduce barriers to actually getting started.

B: Pay to develop reuseable modifications to reduce the cost of A. Once complete, then "B" funding is shifted to other development

C: Pay to lay the ground work for the next project, like a Lunar base, a Mars expedition system, a Martian base, and then cis-Lunar industrial development. (in roughly that order)

NASA will need every penny it can get. If SDV winds up costing $4-5Bn a year, then there is enough for A, but B will suffer, and there will be hardly anything left for C. That ~$2.0B saved is crucial, and adds up to be almost a quarter of NASA's whole spaceflight budget! NASA must have this money if it is to avoid a flags/footprints Lunar program and afford a Mars expedition.

John Creighton · 2005-03-19 10:19:06

This the future, the next 40 years after Shuttle/ISS, the things that we will want. NASA simply can't do all this for a measly $3.7Bn a year. I figure that NASA would need a bit less then double this amount. Therefore, whatever rocket we use, it just can't cost more then ~$2.0-2.5Bn a year to operate. If you cannot promise SDV can do this, then SDV is too expensive.
Think about it... if you save $1.5Bn a year for 40 years, that really adds up, $60Bn dollars! That money is vital to ensure that NASA doesn't get stuck just kicking Moon rocks around a few times a year and calling it good.
NASA has the money to do all this and more... it just can't afford to let it all go into the black hole of the Shuttle Army. Easy enough?

It is interesting to note that the money needed to operate a SDV and do the other things you say needs to be done is exactly that extra 5 billion griffin said NASA buget should be increased by. Forget if it is realistic or not. Would you support a SDV if NASA got a 5 billion dollar budget increase. Even if NASA doesn’t get a budget increase there are cuts in other areas of NASA’s budget that could make up some of the shortfall.

If NASA doesn’t have the money to support SDV, I would strongly encourage NASA to look at ways to increase the rate EELV’s can be launched, the rate they can be produced and perhaps begin research on a RLV. The resulting cost savings from these options should make up for the disadvantages in a EELV based mars mission.

GCNRevenger · 2005-03-19 10:50:49

I don't think it is fair to "forget all that" about how realisitc NASA getting a 33% budget increase is. I don't think that it is realistic, and Griffin is either dreaming or else trying to set a very high number in the hopes of squeezing a few hundred million or $1Bn out of Congress. It was pulling teeth enough to get an extra $800M when other budgets are being cut.

But if NASA were to get a large and regular cash infusion? No, I would still not support SDV. It ain't rocket science, if EELV can do the job for $1-2Bn less then an overpriced SDV, which I think is entirely possible, then SDV is a bad deal. Especially since you would lose out on the flexibility of intermediate launch, economies of scale by pooling purchases with the USAF, and the lower development cost of simply updating today's EELVs.

Boeing can, in theory, build up to 40 booster cores per year and launch at least 12 flights from its exsisting launch pad at the Cape'. I don't know what Lockheed's Atlas-V can do.

NASA is not the most efficent organization in the world unfortunatly, and NASA does have other things to do besides manned spaceflight. I don't think its reasonable to assume NASA could devote more then $9.0-10Bn to spaceflight, in which case a $4-5Bn SDV would still absorb so much of this money that it would be at best a poor investment, at worst fatally strangle what you would do with the rocket, and severely hamper the future beyond whatever NASA is doing at the moment (which I consider pivotal).

A true real-live no-kidding RLV or EELV+ probobly can't deliver pieces of a Mars ship large enough, you really do need HLLV for an efficent Mars program.

John Creighton · 2005-03-19 11:19:53

But if NASA were to get a large and regular cash infusion? No, I would still not support SDV. It ain't rocket science, if EELV can do the job for $1-2Bn less then an overpriced SDV, which I think is entirely possible, then SDV is a bad deal.

GCNRevenger, I don’t understand you position. You yourself said that EELV can’t get us to mars. Therefore EELV can’t do the job. Moreoever, if it takes the same deltaV to go to the moon as go to mars, and mars has more local resources that can be used to sustain a base I really question why an EELV is good for a lunar program but not a Mars program. EELV can do the job but it can’t do the same job and if it only does a half assed job is it really wroth it? Anyway, if you don’t think we can go to mars in a short enough time frame that it will be worth sustaining the shuttle infrastructure just say so. Say you have given up on reaching mars in the short term and I will understand your position a little better.

Especially since you would lose out on the flexibility of intermediate launch, economies of scale by pooling purchases with the USAF, and the lower development cost of simply updating today's EELVs.

I understand the value of medium launch for the USAF and some planetary mission (JIMO) but there are also USAF applications that may need heavy lift. If medium lift is more of a priority for USAF then should USAF pay for the cost? Military spending is already huge in the US and does more need to come from NASA in the guise of civilian spending?

NASA is not the most efficent organization in the world unfortunatly, and NASA does have other things to do besides manned spaceflight. I don't think its reasonable to assume NASA could devote more then $9.0-10Bn to spaceflight, in which case a $4-5Bn SDV would still absorb so much of this money that it would be at best a poor investment, at worst fatally strangle what you would do with the rocket, and severely hamper the future beyond whatever NASA is doing at the moment (which I consider pivotal).

How much of the budget currently is devoted to manned space flight and how much devoted to other stuff. I forget the brake down? Does that 9-10 billion assume stuff coming from other parts of the budget? I know there is talk of some science being cut. There is question by some if a half assed lunar program is worth slashing science. I need more details.

A true real-live no-kidding RLV or EELV+ probobly can't deliver pieces of a Mars ship large enough, you really do need HLLV for an efficent Mars program.

Why not? 20? Only 20% of the NASA in LEO reaches mars. The upgraded EELV is just half to 1/3 of a SDV, so one EELV could carry a mass of 2-2.5 times what a SDV could carry in one shot. Therefore as far as landing stuff on Mars on EELV in the 40-50 MT range could launch as big a piece as directly into mars as two SDV. It would also take only 2-3 times as many sorties per flight. Assuming the worst case 6 flights, I don’t see why the 6 flight can’t be the hydrogen and the 7th flight the crew. You said yourself that you would launch two flights in a three week period. That would be enough time for the hydrogen not to boil off. As far as cost and complexity I would say there are certiny efficiency advantages to doing something routinely. If someone does something every three weeks they are going to do it much more efficiently then they will if they do it every moth. I also question the 3 week time frame. Is there any laws of physics that prohibits us from doing it faster? 8-) What are the limiting factors interms of production and launch rate? It will be beneficial both to NASA and the USAF to figure out how to do this faster. I believe that great cost savings can be made by improving the Launch and production process.

GCNRevenger · 2005-03-19 11:35:59

I'm not advocating using EELV to get to Mars. I am saying that unless it can be shown that SDV won't cost much more then EELV, that EELV is the best option for the Moon. EELV would also come in handy later even with HLLV in order to launch the crews for reuseable Moon/Mars ships or for light supply missions to the Moon, in addition to the other reasons I have listed.

If we aren't going to use SDV to get to the Moon, then yes a Mars expedition is far enough in the future that maintaining the Shuttle infrastructure in the mean time is silly.

The USAF doesn't need massive heavy lift rockets because space weapons won't be that big. A powerful chemical laser or a KEM rocket launcher won't weigh 100MT, and in order to have a weapon on-station when you need it, the USAF would obviously prefer a larger number of smaller satelites rather then a few large ones.

Right now, NASA's budget is about $15Bn. I estimate that given NASA's other non-spaceflight activities, that it is unreasonable to assume that more then ~$9-10Bn of this annual sum could be devoted to it. A $4.5Bn SDV program would absorb fully half the budget, and would make doing anything beyond regular short-term Lunar missions untennable.

"The upgraded EELV is just half to 1/3 of a SDV, so one EELV could carry a mass of 2-2.5 times what a SDV could carry in one shot."

What? You aren't making any sense. The EELV has only about 33-40% (50% versus Magnum std.) of the capacity of a single SDV flight.

For Mars, you would need a larger rocket. The aerobrake shield that NASA prefers must be the same diamater of the HAB, and it is too big (volume) to fit on EELV even if it could lift the assembled HAB/MAV (which is a little too heavy).

I don't think that it is practical to accelerate Delta-IV HLV launch schedules beyond once every 3-4 weeks, since the launch pad, pad crews, and the two VAB buildings at the Cape' can't be pushed much faster. Assembling a Delta tripple-barrel rocket is not a quick and easy procedure. I have little information about what Lockheed can do with Atlas-V.

John Creighton · 2005-03-19 12:07:39

"The upgraded EELV is just half to 1/3 of a SDV, so one EELV could carry a mass of 2-2.5 times what a SDV could carry in one shot."
What? You aren't making any sense. The EELV has only about 33-40% (50% versus Magnum std.) of the capacity of a single SDV flight.

Right I said 33-50% of the capability you said 33-40% more or less the same thing. I also said that 20% of the Mass that will be launched to LEO will reach mars. What I was doing is comparing the Mass that will reach mars with a SDV approach to the mass that can be pushed to LEO with a a single EELV. Zubrin’s SDV can lift 120 MT to LEO. That means one of Zubrin’s SDV will only put 24 MT on mars. An EELV can launch twice this two amount to LEO. The part of the vehicle that pushes this mass to mars could be lunched in subsequent launches. Other SDV can only put 80 MT to LEO. This means only 16 MT will reach mars with one launch. This is nearly 1/3 as much as an upgraded EELV could put on mars. Thus an EELV approach could be enough to push to mars what one or two SDV can but will require two to three times as many launches.

BWhite · 2005-03-19 13:27:47

But if NASA were to get a large and regular cash infusion? No, I would still not support SDV. It ain't rocket science, if EELV can do the job for $1-2Bn less then an overpriced SDV, which I think is entirely possible, then SDV is a bad deal. Especially since you would lose out on the flexibility of intermediate launch, economies of scale by pooling purchases with the USAF, and the lower development cost of simply updating today's EELVs.

Please itemize all the extra "goodies" that are needed to get Delta IV up to 40 MT

Those are NOT free and will creep EELV costs towards $300 million or more per shot.

The supposed savings vanish.

BWhite · 2005-03-19 13:44:26

This the future, the next 40 years after Shuttle/ISS, the things that we will want. NASA simply can't do all this for a measly $3.7Bn a year. I figure that NASA would need a bit less then double this amount. Therefore, whatever rocket we use, it just can't cost more then ~$2.0-2.5Bn a year to operate. If you cannot promise SDV can do this, then SDV is too expensive.
Think about it... if you save $1.5Bn a year for 40 years, that really adds up, $60Bn dollars! That money is vital to ensure that NASA doesn't get stuck just kicking Moon rocks around a few times a year and calling it good.
NASA has the money to do all this and more... it just can't afford to let it all go into the black hole of the Shuttle Army. Easy enough?
It is interesting to note that the money needed to operate a SDV and do the other things you say needs to be done is exactly that extra 5 billion griffin said NASA buget should be increased by. Forget if it is realistic or not. Would you support a SDV if NASA got a 5 billion dollar budget increase. Even if NASA doesn’t get a budget increase there are cuts in other areas of NASA’s budget that could make up some of the shortfall.

This amount of money can come from selling TV rights!

Edited By BWhite on 1111261790

GCNRevenger · 2005-03-19 15:59:38

How about you just read Boeing's own document... http://www.google.ca/url?sa=U&start=2&q … ...&q=http

The real meat is on page 5 and 7. Boeing can produce 40 CBC cores yearly, and the launch pad can theoretically handle 15 flights a year. More then enough for an all-expendable three-sortie-yearly Lunar program.

...These upgrades will be closer to free then you think. Yes they will take up some development money, no doubt about that, but the changes are relativly minor compared to building SDV.

And as I am sure you are agonizingly aware, the majority of the cost of a launch is still tied up in the man power. Since the man power cost doesn't change much if you just upgrade the rocket, the price per unit will not change radically.

The upgrades themselves are relativly simple given today's technology: if you will note on p.7, Delta-IV can achieve 45MT with swapping out the old RL-10 for the new RL-60, which is coming online soon anyway, addition of some cheap SRMs (surely only a million or so each), and modified RS-68R engine. You don't even need the fancy Lithium alloy or superhigh grade LH2.

Atlas-V could probobly also hit the 40MT line in the tripple-core version if its antique upper stage were greatly improved and some of its nice SRMs added.

Given that NASA (or even better NASA+USAF) would get a bulk discount, and I see no reason at all why the costs should substantially increase beyond the baseline $180M "standard" Delta-IV HLV. $200M is more then reasonable, maybe less if Boeing is willing to deal in return for such large contracts.

$300M is clearly a scare-tactic straw man figure Bill, that kind of thing is beneith you.

GCNRevenger · 2005-03-19 16:10:25

"The upgraded EELV is just half to 1/3 of a SDV, so one EELV could carry a mass of 2-2.5 times what a SDV could carry in one shot."
What? You aren't making any sense. The EELV has only about 33-40% (50% versus Magnum std.) of the capacity of a single SDV flight.
Right I said 33-50% of the capability you said 33-40% more or less the same thing. I also said that 20% of the Mass that will be launched to LEO will reach mars. What I was doing is comparing the Mass that will reach mars with a SDV approach to the mass that can be pushed to LEO with a a single EELV. Zubrin’s SDV can lift 120 MT to LEO. That means one of Zubrin’s SDV will only put 24 MT on mars. An EELV can launch twice this two amount to LEO. The part of the vehicle that pushes this mass to mars could be lunched in subsequent launches. Other SDV can only put 80 MT to LEO. This means only 16 MT will reach mars with one launch. This is nearly 1/3 as much as an upgraded EELV could put on mars. Thus an EELV approach could be enough to push to mars what one or two SDV can but will require two to three times as many launches.

Okay, now you are making a little sense...

Problem #1 is that Zubrin's plan calls for payloads that are way too small, by about half. NASA DRM calls for payloads in the 40MT range to be placed on Mars. With the landing fuel and heat shield, it is questionable that EELV+ could lift it in a single flight. The ship itself must absolutely launch in just one piece.

This also increases the amount of fuel and the size of TMI stage you need, which can now no longer lift in a single EELV+ flight.

Problem #2 is the fuel boiloff, but that isn't life-or-death probobly

Problem #3: The EELV rocket is physically too small to accomodate the 8-9m diameter aerobrake shield.

Problem #4: Excessive on-orbit assembly required

Yes EELV to Mars can be done, its just not a good idea.

Michael Bloxham · 2005-03-19 23:24:26

I don't believe The Army will ever be killed. Therefore, your points are hollow. Sorry.

-------------------------------------
Edit: Perhaps some could be fired, but they would probably not be usefull on SDV anyway. Only a small portion of The Shuttle Army actually works on the launch stack, and only these men would continue to work directly on an SDV. So to say SDV would encumber the full cost of The Army is pessimistic, at best.

GCNRevenger · 2005-03-20 08:56:10

I don't think that NASA has much of a choice. Either the majority of the Shuttle Army is eliminated, or SDV will not be affordable.

How do you know that "most" of the The Army isn't nessesarry to launch SDV? You will have to retain all the people involved with reassembling the SRBs, running Pad-39/VAB/fuel farm, running KSC's command center, and so on. I think it is a very valid concern that even if you eliminated everyone dealing with the Orbiter, that SDV would still be over-budget.

NASA has to cut the cost of flying SDV to HALF the cost of flying Shuttle. Right now, only about ~10% the cost of Shuttle is tied up with actual non-Oribter hardware... that is alot of people NASA has to keep paying.

BWhite · 2005-03-20 10:42:33

The math appears to boil down to flight rate assumptions.

If we do not fly SDV at a high enough rate, then EELV probably will be less expensive per pound. But will an EELV-only VSE have a high enough flight rate to maintain public support?

Will an EELV-only VSE make accomplishments fast enough to actually do anything meaningful?

SDV offers the hope of a much lower cost expansion of the VSE when (or if) public support develops. If 12 - 18 SDV launches happened every year, then the cost per pound plummets as the fixed employee base is amortized over a higher number of launches.

In other words, SDV has a higher cost at very low flight rates but allows for a much less expensive ramping up or acceleration of flight rates. Destroying SDV infrastructure means that a genuinely robust space program is off the table for a generation, or more.

If we do that, I predict that what public interest there is in space exploration will plummet and our ability to generate future interest will be much diminished.

Edited By BWhite on 1111337057

BWhite · 2005-03-20 10:49:57

I have been reading a huge stack of marketing books recently. The growing evidence is that consumers are not stupid, despite what the old school advertisers seem to believe.

Space exploration cannot be "sold" to the American people unless it makes genuine accomplishments fast enough to sustain interest.

5 or 6 lunar sorties, between 2020 & 2030, will lead to:

:sleep:

Wingo's mantra, to mine the Moon to save civilization here has a chance of "selling" IMHO if we convince people we are genuinely trying to mine the Moon in less than 75 years.

EELV-only will not let us do that.

GCNRevenger · 2005-03-20 11:52:41

"The math appears to boil down to flight rate assumptions... EELV-only will not let us do that."

NO, no it doesn't. This is not true. It does NOT appear to. Now you are just making anti-EELV excuses like Bob. Your normally level-headed self is really beginning to borderline on intentional beligerance Bill...

John Creighton · 2005-03-20 12:06:35

I am curious Boeing shows the evolution of the delta line and with Pad and factory modifications it can reach 100 MT with one core. Part of the development costs will be paid for by upgrading the EELV to 40-50 MT. Although it probably would cost more then A SDV might it have the merit of having to support less staff. Could the new factory produce both the standard core and the wider core? Could improvements in the factory lead to a lower marginal cost in production? I know the answer is not clear and that is why boeing is doing studies for the government on all three option (EELV, Shuttle derived and clean slate). It will be interesting to see what the future holds.

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