Talk:Why Moderate Sized Rockets Are Better

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I have referred to my concept of Lunar development as "reasonable" in the article, and as "rational" in other places. This means little without the basis for deciding what is reasonable. I take profitability as my basis for deciding. By investment standards profit from Luna is so risky and removed into the future as to make money spent on development no investment at all. The same standards can be used to evaluate development decisions regardless. One merely imagines a very low rate of return for an investment that does not mature for a very long time and is very risky, and then does the best possible within those limitations. One plans for various contingencies. Every thing I know about lunar development indicates to me that if people follow through persistently the environvent of lunar investments will change in the distant (perhaps fifty years) future. There will be a high rate of return and secure knowledge of performance. Making decissions based on profitability leaves some chance of failure; but the Apollo on steroids strategy leaves little chance for success unless your goal is leaving a few footprints on Mars and proving once and for all time that space exploration is just too expensive to have any practical benefits.--Farred 17:31, 26 March 2009 (UTC)

  • Why did I call investment on Luna "risky" if everything I know points to future high returns on investment? Does not long time to maturity cover the entire set of adverse conditions? It is not what I know that indicates risk in lunar investments. It is my ignorance. The total of human knowledge about Luna is much greater than my own, but the total of human ignorance about Luna, as a fraction of my own ignorance, approaches unity. So there is a vast area out of which the risk of failure arises. Also, there is no guarantee that the individual person, corporation or nation that invests in lunar development will reap the profit. There is no guarantee that others will follow through with investments made today to the point that a profit is ever achieved.
  • Those who care for nothing but the amount left in their retirement accounts at death, those who feel faint at the thought of risk and those who think humanity utterly incapable of sustained efforts of more than twenty years should have nothing to do with lunar investment. Those who think that the spark that caused man to irrigate the Babylonian empire and build cathedrals is still operating and still admirable should consider the effort of lunar development worthy of itself whether they can live to taste the fruit or not.--Farred 15:29, 28 March 2009 (UTC)

I had a feeling an article like this would be created at one point. I won't comment on the "launcher size argument", but I have a problem with asking for the cancellation of the Ares V. The Ares program has it's own problems, most not attributable to launcher size. Ares I has become a big problem, not Ares V. Constellation might just cancel itself- it certainly does not need a bunch of space advocates to worry about it. Also, one must not regard NASA as our only path back to the Moon...

T.Neo 18:33, 30 March 2009 (UTC)

  • Who should invest in lunar development? Individuals, organizations, corporations, and governments who have resources that they can afford to loose and who want to help create a prosperous and secure future for humanity. It is not yet time to get shares in development corporations that might in the future be worth enormous sums to your heirs. Governments will get around to laying the international legal groundwork for such corporations eventually. Perhaps without any delay to development work caused by waiting for such legal groundwork. More knowledge is needed about just how lunar development might proceed so negotiators know something about what they are negotiating. Governments will also want to assure the ability to inspect lunar developments to insure that they are militarily harmless.
  • Why should we invest in lunar development? It has been mentioned elsewhere that lunar materials could be used for space based solar power and orbiting space ports. Besides this, a space based civilization could possibly avoid disaster by climate change of the run away greenhouse or run away ice age types that have been suggested by various sources. (Which of these catastrophes Earth's chaotic climate will throw at us is still in doubt, and may depend upon what we do on Earth.) Just as industrial capabilities of some nations on Earth have doubled and doubled again within the last couple of millennia, capabilities of a space based civilization would be expected to double repeatedly, with a much higher upper limit to the possible capabilities to be attained. Shading Earth from the sun as it starts to enter its red giant phase and even moving Earth farther from the sun are well within the capabilities that could be attained. Man will never attain any of the grand capabilities without taking the first step of industrializing either Luna or Mars. The second step will get us the pair.
  • Unfortunately avoiding the possibility of military self destruction will not be available for quite some time (not until people build colony ships to send to other stars). As people gain more space based capabilities, we will realize new and more powerful ways to kill ourselves. We will simply need to continue to talk to each other and convince ourselves not to kill each other.--Farred 16:11, 4 April 2009 (UTC)
  • What sort of efforts should be made to develop the resources of Luna, Mars and Ceres? Here are several points to consider.
  • First we must recognize that the chief economic advantage of these places is the potential for cheap transportation of either raw materials or processed products into orbit.
    • From Luna only about 0.4 kilowatt-hours of energy must be transferred to a kilogram payload to put it into orbit. If the over-all power efficiency of an electric launching system is 40% then it would use one kilowatt-hour per kilogram of cargo launched into orbit. At current earthly rates for electrical power that would be less than a nickel a pound. What the cost of a kilowatt-hour on Luna will be is subject to change, but the potential for low cost shipment of cargo to orbit is there if a large scale market is developed. Allowances for interest on the capital investment and maintenance also are less per pound if there is a large scale market for launch services. The situation is considerably different from that on Earth where the savings from increasing the size of the market are limited from the inefficiencies of scale that hinder the launch market on Earth, such as the increasing cost of liquid oxygen and land area for launching pads as these items become more expensive when demand goes beyond a certain amount.
    • Mars also has large unused resources which could be pressed into service to launch cargo to orbit. Luna could benefit from receiving hydrogen, nitrogen, carbon, and argon from Mars and pay for it with money from the sale of raw and processed materials to orbiting factories. A single stage to orbit fully reusable space craft is much easier to design for Mars than for earth. ( added 27 May 2013 ==> ) Mars has the advantage of having nitrogen and argon more conveniently available for an atmosphere for life support of workers than Ceres. Human workers would likely be required to extract resources from either Mars or Ceres vecause of the long communications delays involved.
    • From Ceres about a fortieth of a kilowatt-hour is sufficient to launch a kilogram of cargo to orbit. Launch system efficiencies should be high because a simple device like a merry-go-round could accept cargo near the center without stopping and drop it into orbit at the rim. Two cargoes launched tangentially to the surface at escape velocity in opposite directions to balance the launcher would end up going in almost the same direction. They could rendezvous with each other with a reasonable amount of maneuvering fuel. If it is preferred to have a station in synchronous orbit about Ceres as a depot, cargo could go up and down a 426 kilometer long cable between the depot and Ceres. The cable could continue to 663 kilometers above the equator of Ceres where it is possible to simply drop cargo into an escape from Ceres trajectory. This would be a possible place to anchor the tensile load of the cable with the lower end anchored on Ceres. The depot at 426 kilometers would remain attached to the cable but have very nearly zero net force transferred between the depot and the cable. Cargo containers could be gathered at the depot and loaded on an interplanetary tug which could dock weightlessly at the depot. Such a tug might use partially ionized oxygen gas as reaction mass of a VASIMR rocket.
  • Second, any human presence will require a massive industrial establishment to support it from local materials. Having many people to operate such a system would be counter productive, because then it would be necessary to have more machinery to support these workers. Automatically functioning redundant machinery for life support is therefore necessary for economic use of these places. The priority in developing a space based economy is not having people in orbit supported by Earth based supply but developing automatic machinery that can operate by remote control.
  • Third, Luna is the closest source of materials that could potentially be launched into orbit at a cost of less than a dollar a pound, when the development work is done. It has a round trip communications delay of less than three seconds, which is suitable for some sorts of remote control that are not practical for Mars.
  • Fourth, there are many special conditions at Luna, at Mars, and at Ceres that provide a special advantage or require special efforts to accommodate. For example, the low light intensity a Ceres could be countered by ultra light weight mirrors bent into a parabolic trough shape in the weightless area of synchronous orbit to concentrate light either on solar cells or on the hot end of a heat engine. Trade could provide volatiles to Luna from Ceres and Mars, manufactured goods to Ceres and Mars from Earth and Luna, solar power to Earth from Geostationary orbit, and raw and processed materials to Geostationary Earth orbit from Ceres, Luna and Mars.
  • From all of these considerations it seems that the most important thing to be done now for developing a space faring civilization is learning all the details which determine how much it costs to start taking advantage of the opportunities offered by places like Luna, Mars and Ceres. Various plans for using these resources in complimenting each other should be considered and evaluated in light of the details of the physical condition of these resources. When the best plans that will actually turn a profit are discovered, the legal framework for investing in earnest should be available.
  • Of all the robot spacecraft, rovers and automatic experiment packages that could be launched to learn what we need to know to develop a space based economy, none needs to be launched on a Saturn V class launcher. Since it is necessary to develop remote controlled industry including remote controlled manipulators to get a space based economy started, any large platform needed in space should be assembled from pieces that can be launched on moderate sized launchers, which launch cargo for less per pound than the Saturn V class launchers. Assembling large platforms from smaller pieces is practice for the automated and remote controlled work that will be necessary for economic development of extraterrestrial resources.
  • A fully completed International Space Station (ISS) may not be the most economical resource possible for doing experiments in space, but we are committed to supporting it for a while. Research done at the ISS to support automated space manufacturing could be helpful. When the time for which we are committed to supporting the ISS is expired, there should be a hiatus in the manned space flight program. This should continue until the unmanned efforts have developed resources to the point that people can be supported cheaply enough on local resources and there are sufficient resources in space for people to do things that make economic sense.
  • The hundreds of times reductions in the cost of lifting stuff to orbit that NASA has sought will not happen before there is development of infrastructure in space, because all schemes for reducing the cost of lifting stuff to orbit by such a factor are dependent upon a high volume of traffic that can not be sustained without the development of the infrastructure necessary to make it profitable. Do the exploration and development work with light weight long endurance robots first and high volume reductions in the cost of getting to orbit will follow. The long reign of NASA's wishful thinking based launch system development plans should be at an end.--Farred 03:52, 11 May 2009 (UTC)
  • I heard a NASA employee, Pete Worden, knock space based solar power on www.thespaceshow.com. He claimed one can not make a business case for space based solar power, and his argument assumed the cost for putting a space based solar power facility into orbit from Earth with currently available launch technology. I had to agree with every thing he said. He does a good job. He even pointed out that the ability to launch the necessary stuff from Luna would not be available for decades, also true. I would certainly discourage anyone from investing in trying to launch a space based solar power plant from Earth. Anyone offering such an investment likely just wants to take people's money, without risking jail time. The ability to launch the necessary stuff to orbit from Luna will never be available without the necessary effort of prospecting on Luna and developing an industry there. There is nothing that would force NASA to have that kind of program, but at least it looks toward a future benefit for mankind. It could make honest legislators out of those who said that their support for NASA funding was support for the future of mankind. Can anyone make a business case for an Apollo on steroids program? Perhaps Google will offer a prize for the most billions poured down a rat hole.--Farred 02:06, 13 May 2009 (UTC)

If you look closely, you'll see NASA has been operating a large launch vehicle in the form of the shuttle, for more then 20 years. This shows that such a launcher is not impossible to operate. The shuttle launch configuration has only failed on launch once. While the useful cargo to orbit capability of the shuttle is in the same range as numerous "moderate sized rockets", the hardware is on the same scale as a larger launch vehicle. We will not get far with either small rockets, or the current technological conservativism exhibited by NASA. T.Neo 19:31, 13 May 2009 (UTC)

  • The comparison of large launchers to the Space Shuttle is well made. It adequately shows the lack of economy.--Farred 01:40, 14 May 2009 (UTC)

Economy? Do you mean a space-based economy? T.Neo 06:50, 14 May 2009 (UTC)

  • How can anyone misunderstand me? I mean the Space Shuttle and Saturn V class launchers both consume money like water under high pressure gushes out of a two foot diameter pipe.--Farred 21:50, 15 May 2009 (UTC)

How can anyone misunderstand me? I mean the Space Shuttle and Saturn V class launchers both consume money like water under high pressure gushes out of a two foot diameter pipe

The shuttle has an orbiter vehicle that has to be refurbished after every mission, something that, for example, a shuttle-derived heavy lift vehicle would not need. I was merely making a comparison between the scale of the hardware.

I'd like to make some points:

  • The big effect of the Ares V would be eating up the lion’s share of the budget to first construct the construction facilities, then build the rockets, then maintain the outsized facilities for construction and launch of rockets that get used every other year

The hardware for building and launching the Ares rockets already exists. It only needs to be modified, not constructed from scratch. Not to mention that such "outsized facilities" have been in use for the last 20 years.


  • Sending up three rockets, two of them Ares Vs would have three chances to fail and ruin the mission while sending up eight smaller rockets would have eight chances to fail and ruin the mission. If on the other hand sending a human mission to Mars is worth doing a dozen times, there will be spares of things that need to be launched for any one mission. If one of the smaller eight rockets needed to launch a Mars mission fails, its payload will tragically be lost, but the corresponding components from an upcoming mission will be moved up in line and the mission will go on.

What prevents hardware from the next mission being used as backup hardware in case an Ares V launch fails? Why is this restricted to smaller rockets? Any hardware destined to be thrown away for each mission should be mass produced and easy to replace- NASA even constructed a backup Skylab.

T.Neo 13:59, 16 May 2009 (UTC)

  • Thanks to T.Neo for pointing out that I failed to make a few points clear.
  • The fact that the Ares V would use the same launch facilities as the Space Shuttle is one reason for the excessive cost of both. The Ares V does not share every defect that makes the Space Shuttle outrageously expensive, but our goal should not be to make a launch system that is marginally less outrageous in its excess cost. Our goal should be to use the most economic launch system that fits our purpose. I realize that the money gushing out of the federal coffers to pay for the prodigality of the Space Shuttle program is not only a shameful waste. Some see it as the money that puts food on the table and pays for the children's college education. It is not my intention that people should be bereft of employment because of scrapping of Space Shuttle facilities. NASA has an obligation to help its displaced people find other positions. Some should actually be employed in helping the others adjust. It is part of the cost of shifting some programs to a theoretical long term profitability approach to management decisions. I expect people to face up to the problems of shifting employment as superior to getting NASA to continue employing them in a manner that causes actual detriment to the cause of humanity's future in space.
  • To whatever extent facilities must be constructed, modified, and/or renovated for the construction of the Ares V, the expense is a waste. Maintaining such facilities is a waste. Manufacturing the Ares V would be a waste and maintaining launch facilities for it would be a waste. We already have facilities for moderate sized launchers. They are cheaper to use and are cheaper yet per pound of cargo if facilities are used more fully. The type of facilities expense that makes sense is opening another launch pad for moderate sized vehicles and increasing the production capacity for the vehicles. The more commonality within the launch vehicle fleet, the cheaper it is to produce and maintain them.
  • My point about the mission to Mars cargo of a smaller rocket than the Ares V having a spare in line as a replacement in a well run program was merely to show that Scott Horowitz' argument that a smaller rocket would cause a higher risk of loss of mission was in error. Of course a mission that would use an Ares V would have spare hardware that could replace a cargo lost to launch failure, if it were actually intended to launch a dozen missions to Mars. There would be a smaller chance per mission of a launch failure, and a bigger cost per failure. My suspicion has been that some in the space activist community care nothing for economic development of Mars, Luna, or any other place off Earth. They just want to see the first footprints on Mars made by a U.S. citizen, and anything happening on Mars after that is not their concern. If they want to prove their concern for a Mars colony, they should support the kind of program that would be necessary for it.
  • Wernher von Braun wanted smaller rockets than the Saturn V used for sending men to the moon. His idea would have required a space station for construction of the moon vehicle in orbit. We are lucky that he bowed to time pressure and used the Saturn V rocket, because the technical ability to build a functional space station did not exist at the time of the Apollo program. If he had had the time he would have tried to build a manned space station as an orbiting wheel, and it would have been an impossible task without first making several technical advances. As it was the Apollo program succeeded in scientific progress even though it had only political goals. Things have changed. We can not simply repeat the space missions of the past over and over and expect fame for anything but foolishness.
  • The time has come when economic development of Luna is possible. It would be a long and difficult process, but it would open up the economic colonization of the whole solar system.--Farred 19:42, 17 May 2009 (UTC)

While some of the points you make are intriguing, and I find your different ideology fascinating, I still disagree. I'd say building and operating a fleet of ~30 components, each with automatic docking systems, thrusters and avionics, is a waste of money. I also think we shouldn't base our methods of exploration on those proposed by a man in the 1960s. And trying to change NASA's direction, is pointless. Others have tried and failed. T.Neo 08:21, 19 May 2009 (UTC)

  • The trouble with NASA is that it is operated with an entitlement program mentality. The human space flight people do not think that they are obligated to provide some benefit to the country or to humanity. They consider that they must be employed by the federal government for human space flight because that is what they do, and since that is how things are done, that can not change. The Michoud production facility might keep on producing either shuttle external tanks or Ares-Vs not because they are needed, but because as T.Neo said,"trying to change NASA's direction is pointless". Economic distress to the workers, the communities, and the contractors associated with NASA would result from stopping any program, and congressmen want to avoid economic distress in their districts. The Space Shuttle would have continued on forever in spite of excessive cost if it had not killed astronauts. This is what should be changed in NASA. Production of Ares-Vs should depend upon a need for Ares-Vs. Since there is no need for such a massive amount of cargo into orbit as would efficiently use Ares-Vs, there should be no Ares-Vs. It is the launching of one a year or one every other year that makes the Ares-V so inefficient. The launch facilities and the manufacturing plant are just as expensive to maintain if you manufacture and launch one a year as they are if you manufacture and launch twenty a year, and they are mighty expensive.
  • NASA desperately needs direction. There is no need to change NASA's direction for human space flight, because it has no direction now. The theoretical long term profitability criterion can allow NASA to accomplish the ground work for people doing profitable work in space. On the way it calls for a hiatus in manned flights and the cancellation of Ares-V.--Farred 00:38, 24 May 2009 (UTC)
  • I am a mostly peaceable person. A Japanese soldier killed my uncle in the Philippines, but I do not blame the unknown Japanese soldier, probably long dead. The failure of proper international relations was at fault for U.S. and Japanese soldiers killing each other. When someone is found to have committed serial murders, I approve without anger of that one's death, because it helps to maintain social order. If people abolish the death penalty, I do not complain. Warehousing serial murderers is an alternate expense to dealing with the legal ploys of fanatic anti-death-penalty lawyers. However, I think I can work up a little anger over the Ares-V and the whole Constellation program.
  • The Space Shuttle fiasco can be somewhat excused because of ignorance, but NASA with eyes wide open made plans to keep expensive Space Shuttle infrastructure as a make work project when NASA is finally forced to abandon the Space Shuttle. It would be better to have half the displaced workers digging holes while the other half fills holes in. There is no possibility for a sufficiently massive space program to efficiently use the capabilities of a Saturn V class launcher. Instead of falsely labeling space development efforts as hopelessly expensive, lets put the blame for excess expenditures squarely where it belongs, with the entitlement program mentality of the president and congress. Employ the Space Shuttle workforce with federal funds if necessary, but do not bill useless programs to the space development budget. T.Neo points out the duplication of thrusters for space maneuvering that could be avoided by using 2 Ares-Vs instead of eight smaller rockets for a manned Mars mission, as well as duplicate electronics for controlling those thrusters and controlling the to orbit trajectory. The actual actuators to control the assent of smaller rockets are proportionately cheaper than their Ares-V size counterparts. Electronics have gotten cheaper since the Saturn-V. Rockets have not. I would write that T.Neo strains out the gnat and swallows the camel, but a camel is so pitifully small next to an Ares-V. Like the ancient Thai kings would ruin a subordinate by giving him a white elephant, congress can ruin space development by giving NASA an Ares-V. I only wonder whether or not that is the intent.--Farred 16:43, 25 May 2009 (UTC)
  • I fixed a typo, made a punctuation change and a format change above to make it easier to read without changing the meaning. I also made an addition labeled as a recent addition. I hope no one objects.
  • I chose the wrong item to suggest diseconomies of scale when I wrote "increasing cost of liquid oxygen" above. There is no prospect for going beyond the range of greater economies of scale with more liquid oxygen use for rocketry. For land use there might be but I am not capable of stating for a list of required inputs for launch to orbit which will have diseconomies of scale and when diseconomies appear.
  • There are some things that do not change much in fifty years. The reasons for Wernher von Braun wanting to use smaller rockets to launch to orbit and assemble moon and Mars vehicles in orbit are still valid. More frequent launches with smaller facilities would have been cheaper than Saturn Vs. The savings would not be obtained for free. Rendezvous and docking with fuel depots and assembly facilities in orbit would be required. There is no reason to be in a great hurry today. We can develop the facilities in space and put them to multiple uses. Because of current fiscal limits we probably need to wait for the end of the ISS program before any useful robotic space station can be developed. Robonaut program data and all ISS data can be archived for future use. Robonaut and any anthropomorphic robot will have no place in an economically run space station, just as there is no place for a switch board operator in a modern communications satellite. - Farred 05:53, 27 May 2013 (UTC)
  • The Ares V was canceled but the successor Space Launch System was enough like it to be thought of as the undead Ares V. David Leestma, space shuttle veteran, said that the Space Launch System "will be safe, affordable and sustainable."YAHOO! NEWS It is what one expects from a loyal worker backing up his boss. Bolden's boss is Obama, who approved the thing. We can guess that political considerations entered into the decision but I discuss practical and economic considerations. The SLS might well be as safe as other rockets that launch people to orbit, which is one of the reasons that astronaut work is dangerous. The affordability of the SLS is open to question. Can we really afford to put development of space resources aside to build a huge launcher that will certainly not have as low a cost per kilogram as the best moderate sized launchers? I have not read of any requirement for such a huge launcher that could not be met with moderate sized launchers, a refueling depot, and on orbit assembly of space vehicles from sections made to be assembled in orbit. Does sustainable mean anything other than affordable? Perhaps Leestma means that after the 16 available space shuttle main engines are used up in the first four flights of the SLS, a new expendable version of the SSME can be built to use on following flights. Nothing in the SLS will be reused, which is not the big fault of the SLS. The big faults are the high cost per each flight, the low flight rate (one half to at most two per year) and the high fixed cost for facilities for a monster sized undead version of the Ares V.
NASA Administrator Charles Bolden said that the SLS will create good-paying American jobs. That is, he admits that the SLS is a jobs program, but is it a space program? Bolden said that the SLS would ensure U.S. leadership in space.NASA Beyond Earth What sort of leadership did he mean? First prize in the big rocket competition? For any practical purpose the SLS is a handicap compared to moderate sized launchers, unless there is some secret payload that simply cannot be launched on a smaller launcher. What is the big payload? NASA's budget does not reveal added funds for development of some huge payload. The most likely situation is that the SLS is just a jobs program preventing highly skilled people from doing something useful instead of running the SLS. Obama is copying one of the worst faults of the U.S.S.R. There is always the comfort that Obama's time in office is limited. The Saturn V was scrapped for financial reasons and so the SLS can eventually be scrapped also. - Farred 03:41, 10 June 2013 (UTC)
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