Hi, everybody this is Joseph Friedlander, continuing a guest article series on Nextbigfuture.
In Praise of Large Payloads for Space by Joseph Friedlander Part 1 is here
In this series I hope to discuss first some of the largest systems proposed to reach orbit with big payloads, and then why it’s a lot better (for equal cheapness) to have one big payload than say a million 30 kg payloads launched for a given project—and then some discussion of what those projects might be!
Last time we covered:
• LIBERTY SHIP
• SEA DRAGON
• ORION and SUPER-ORION
There was also a series of studies under the NOVA nameplate conducted by NASA from January 1959 to February 1962.
The excellent article by Mark Wade-- with accompanying ink style drawings-gives us details.
"Despite the selection of Saturn in 1961, studies on Nova continued into the middle of 1962. There were those at NASA headquarters who advocated using large solid rocket motors in place of an F-1 liquid fuelled first stage. They were sure these could be developed in time for the deadline, allowing the use of Nova to launch a direct landing mission to the moon. The first Nova did not finally die until the great ‘mode debate’ was settled in June 1962 with the selection of lunar orbit rendezvous for the landing method. This marked the end of consideration of Nova designs dedicated to launch of a direct-landing Apollo spacecraft.
But was not quite the end of Nova. The launch vehicle was now recharacterised as the ‘next’ launch vehicle after the Saturn V. Design objective was a million-pound payload to low earth orbit. Two major rocket companies that did not receive production contracts for Saturn stages - General Dynamics (Convair) and Martin Marietta - were given ‘consolation’ study contracts for Nova in July 1962. Philip Bono of Douglas Aircraft characteristically did his own study without a contract. "
Thus by September 1963 a new crop of rather amazing designs were out.
These are all copyright Mark Wade, Nova illustrations Check out the Saturn V on the left for scale!:
http://www.astronautix.com/graphics/n/novammgd.gif , copyright Mark Wade
The Mark Wade article above (Astronautix) concludes the fun part with "By the end of 1963 NASA no longer foresaw any need for such huge launch vehicles. Saturn V studies had already begun which indicated that, using solid strap-on motors, the Saturn could deliver up to a million pounds to orbit without the need to build new vehicles or facilities. More importantly, most at NASA saw the follow-on to the Saturn V to be a reusable winged shuttle, which would land at air strips and be fully reusable. Nova was cancelled quietly in 1964. However throughout the 1960’s visionaries like Truax and Bono continued to design and advocate very large or single stage to orbit designs like Sea Dragon and Rombus. But in the absence of political support for human colonisation of space or exploration of Mars, the need for such large launch vehicles has not materialised to this day."
Since this series is focused on what we would do with this amazing lifting capability (500 tons is a million pounds) rather than a comprehensive listing of all schemes for lofting huge masses, (and there are many!) we will now move on to what we would do with large and cheap payloads. Nova would be large but not cheap, (and the recent Ares V, perhaps 185 tons to orbit)
Suggested uses for large payloads run into trouble with expensive rockets-- because of what I call Friedlander's Paradox of Expensive Rockets--- when you are spending a billion dollars or a good fraction thereof on a huge lifter--of presumably high reliability-- you are not going to cheap out on the payload. The public sector dominated organizations you built to build the expensive rocket (speaking widely here--alluding to both NASA and the major league contractors in one allusion because they are both feeding off the public dime) simply will not consider ways to cut costs because it does not have as 'professional a feel'--because what if the rocket works and the payload doesn't?
Public sector dominated organizations are loathe to invite ridicule. The miracle of hurling a payload straight to Mars is forgotten if the payload crashes; then the late night comics start making their jokes. Yet 25 pyrotechnic devices and stage ignitions combined may have worked perfectly-- only the final parachute and retro may have failed.
It is like the feeling behind "nobody ever got fired for buying IBM"-- if you were an executive in the 60s and 70s who knew nada about computers but knew all about corporate politics, you chose the safe and expensive option because if things went wrong, you paid for the best and you could defend yourself in an accountability meeting.
Contrast this with Burt Rutan's Spaceship One-- working on a relative shoestring, he took educated technical risks with disregard of the prevailing 'safe' opinions. This is what hardly ever happens in the public sector except with extraordinary managers (think of the NRO and Kelly Johnson in the 1960s)
An analogous psychological rejection mechanism may be at work in the case of the expensive booster. "How are you going to get payloads for it?" The rejecting observer thinks of the incredible effort to prepare very expensive payloads one at a time, and the mind boggles at the idea of risking say 50 spy satellites at one time on one launch. If it failed... tens of billions of dollars!
This is the chicken and egg problem of cheapness. If your rocket costs a billion, the payload that costs a million seems too cheap. If your rocket costs a million, are you going to risk a billion dollar payload on it?
The way around this in my view is to do what the plan was in the 1950s-- orbit parts and assemble things in space (on the Moon counts as well.)
Incidentally, we have to get past the 'you can't prepare 60 payloads at once' complex. How do we do this in everyday life? Containers. A cargo ship may contain 5000 separate payloads in separate containers. The different organizations preparing each of those don't consider each other's business. They prepare the payloads, seal the container, and hand it over to the shipping company. This was the logic behind the old NASA Getaway Special (GAS)-- http://en.wikipedia.org/wiki/Getaway_Specialsealed
contingency shuttle cargo bay payloads that could be switched on and forgotten by the astronauts. A great idea, throttled by uncertain flight availability and the Iron Law of Bureaucracy in NASA. In the future, such an approach on a space station or a moonbase would enable huge progress-- more so if a human tended or teleoperated upgrade of the container was available. A lab tech on the Moon during your experiment while you teleconference-- a lot of work could be done that way. But we are getting ahead of ourselves.
The Aquarius launch system
from the above Aquarius Concept
* Launch low-cost supplies on a low-cost vehicle
* Low-cost, easily-replaced consumables such as water, fuel,
food, and air are needed by the International Space Station
and military spacecraft
* Launch failures are acceptable since the intrinsic value of the replaceable consumables is low About one-third of the launches are expected to fail
* Lowest-cost vehicle is a single-string, single-stage, single engine
* low-margin vehicle built using non-white-glove labor and facilities.
* Low margins are consistent with a one-third failure rate
Since stringent protection of reliability is not required, the cost per pound to orbit could be $500, an order of magnitude below that of any present launcher.
Part 1 of Aquarius video: http://www.youtube.com/watch?v=mEHawjnn4Ak
Part 2 of Aquarius video: http://www.youtube.com/watch?v=L-Mko5sC5yM
In the videos, the analogy is given to open water conduits and electricity losses cross country including all conversions from multiple transformers to the end users: You expect to lose 1/3 the product. But enough gets through on a reliable schedule that you don't care.
This is exactly similar to the military attitude toward supplies-- they expect to lose some portion through pilferage, losses, enemy action on land (bombing) and sea (torpedoing). As long as enough gets through (a large enough proportion that the losses are not cost-prohibitive) the mission can go on.
Note that if the Aquarius payload is only a ton, it requires military like logistic flows to guarantee large amounts to low orbit. Launching large barges full of these things in a sustained series of operations-- see the pdf
It would take 150 launches to equal a Saturn 5 to orbit. The real inflation adjusted cost of a Saturn V's orbital cost (if it magically was launchable tomorrow--for just bare launch cost vs the real cost of say 10 years and 10s of billions of dollars development) would be perhaps 10 times that. Yet consider the effort in the International Space Station (for example) to use the robot arm to seize the rendezvoused capsules and put them in storage (let alone unpack them)-- and you will see one reason for this series-- large payloads can be assembled on the ground with cheap labor (vs. astronaut time at say $100,000 an hour)
Chicken and the egg, again, by the way. Suppose you had not ~$1200 a kilogram like Aquarius (500 a pound) but $12 a kilogram-- a hundred times cheaper-- then you could build a cheap space station, far more economical to run than the 345 ton $100 billion ISS. (At $12 a kilogram, a station of that mass would be under $5 million to orbit!) When the incentive is sufficient, self-configuration will be engineered to the point of teleoperated robot support, if not to the point of human habitation. However, this series is titled In Praise of Large Payloads-- so lets' continue on our main theme.
Without cheap prices per kilogram orbited and without huge mass throughput to space, the only business models so far that have made large-scale financial sense are data gathering and relay through satellites. In other words, information has no mass. But this series will consider other business models as well.
Supposing we had huge cargo available cheaply in orbit in large packages. What could we then do?
-A typical Mars orbiting mission from Low Earth Orbit (to Low Martian Orbit) and back would need 1000 tons of fuel to send and return a Skylab like ship.
-Private space stations-- similar to the ISS in mass but designed along the cheapness of underwater pressurized modules. (What I call the 'Diver Dan' analogy) Private spacesuits would presumably be cheaper than the current versions.
What could be done at these stations?
-experiments not doable on the International Space Station because of concern for the station's safety,
-experiments too time consuming to do on the ISS with its' jam-packed timelines
-experiments by parties who want to do the science but don't have the money or patience to jump though the current bureaucracy's hoops.
Consider basic experiments on the behavior of matter in microgravity. If they are judged too simple, too complex, too (fill in your word here) they will not pass the approval process.
Now look at http://www.youtube.com/watch?v=vaXIKpDhGyA
This was done on astronaut Don Petit's spare time. See this link
Yet experiments like these are precisely what need doing on a massive scale if inventors are to get a 'feel' for how matter can be manipulated in space. Imagine a zero g metal furnace to melt down Aquarius stages (see above) rather than deorbit them. How would the glob of hot aluminum behave? Could you draw new sheet metal from the recycled booster stage?
The danger would make it impossible to risk a 'national asset' class ISS but the experiment needs to be done. Private space platforms even of the 10 ton class might be able to do such experiments.
The key thing is, that the more opportunities to do science-- impromptu science, science on the spur, inventors trying things out without needed a formal bureaucracy's permission first-- the more space processes will be found. If you work on stem cells on Earth--you are optimizing your mind to find new approaches to stem cell applications. You might have an idea on stem cell work in a microgravity (space) environment-- but realize that you know no one who has any chance of flying soon or any expertise in doing your kind of work, so you forget it. Suppose however that there were dozens, even hundreds of flying commercial labs. If you could instruct a lab tech how to run your experiment, and have it handled while you watch the video, and give constructive feedback, your chances of getting flown and tested would be hugely better.
Large cheap payloads make it possible to use ship like technology to construct hardware which, though heavy by current space standards, is cheap enough for a small organization or company to afford. (Millions to tens of millions of dollars) The more approaches are tried (and the unsuccessful ones discarded), the more robust our developing space capabilities will be.
But with public sector dominated organizations the trend rapidly decays to one or two favored/politically protected/academically backed approaches, which are overwhelmingly unlikely, of the thousands of preexisting possibilities, to have been the one or two best candidates. (Freeman Dyson has written of the development of the TRIGA reactor, and how he thought that lack of sufficient experimentation in early reactor design and emphasis on government on picking winners froze designs before they were optimized. The result has been decades of a subpar nuclear sector; only now are new designs emerging as a new generation of designers rediscovers the universe of reactor possibilities.)
Analogously, the universe of launcher designs has been prematurely frozen for decades; only now are a new generation of designers exploring the possiblities again. Yet nearly all the emphasis is on the launch vehicles, not on their payloads. This series itself keeps on returning to both-- chicken and the egg, we seemingly can't get away from that metaphor in talking about the human breakout into space.
If one has a small rocket engine-- suitable for a lunar lander or an upper stage from Earth launch-- that engine is more than adequate to drive a cheap space station (of Skylab class or better) on a heliocentric trajectory to an asteroid or Mars. Gerard K. O'Neill wrote in his book, The High Frontier,
1975 Summer Study
of a future where space colonists could build (in pressurized, zero-g assembly bays) spacecraft analogous to small yachts, travel in 'wagon trains' firing small rocket engines over weeks, using sextants on the stars for navigation--such a reality would make space exploration of asteroids easy enough for small nations to undertake.
So another use for large payloads would be, shipyard/space dock/assembly bay capabilities--perhaps to assemble many small payloads into large final configurations! But the preassembled large payload's labor saving helps us bootstrap till the point of economic viability.
In an analogy, Daniel K. Ludwig, around 1967-1981, had a plan for the Jari project--http://en.wikipedia.org/wiki/Jari_project which was an attempt to make a woodpulp tree farm in the heart of Brazil. To do so, the American billionaire Daniel K. Ludwig had a turnkey pulp mill built in modular barge form in Japan--
Ludwig had also commissioned two large ship-shaped platforms that were built in Japan and floated to the Jari Project. One barge module contained the pulping sector of the pulp mill. This module housed the digesting the brown stock the bleach plant and the pulp machine. The second module housed the recovery boiler, the evaporators and the recaust. The pulp mill barge was finished in 1978 and launched on February 1. It traveled through the Indian Ocean and through the Cape of Good Hope, arriving at the Brazilian city of Munguba on April 28. The power group module arrived four days later. Both barges were floated into specially built locks. Hundreds of gum wood piles had been driven into the ground to support the two barges. By closing the locks and pumping the water out, the barges gently settled on the many piles.
By having this industrial plant built in a controlled environment and towed halfway around the world, Ludwig avoided the huge logistical difficulties of building small piece by small piece in the middle of a wilderness-- by analogy, exactly what we are discussing. 1000 man-years of work put into something on the ground is 1000 man years that does not have to be provided in space--even if teleoperation is cheap, the work is already done in the case where we can build on the ground and launch in one or a few units. Ultimately, once we have a beachhead in space, on the Moon, at other sites, we can build these units in space. But to start the whole process, large cheap payloads are enormously helpful, cutting years off the bootstrapping timeline.
As Brian has said, 3 guys in a camper doesn't do the job of conquering space except in a symbolic way. A D-Day scale operation (over a century) was necessary to bootstrap the settling (say) of New England. For the price of the stimulus package, we could have done such a D-Day invasion of space (over time; certainly not since fall of 2008). The new economic growth that a new frontier makes possible-- and supplies of metals and energy-- could begin to bootstrap a new multi-world economy to replace the old world economy under crisis today.
This ends Part 2 of In Praise of Large Payloads. In Part 3 we speculate on the new industries of space that massive logistics may make possible.
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