Date: Thu, 3 Jun 93 05:14:19 From: Space Digest maintainer Reply-To: Space-request@isu.isunet.edu Subject: Space Digest V16 #662 To: Space Digest Readers Precedence: bulk Space Digest Thu, 3 Jun 93 Volume 16 : Issue 662 Today's Topics: DSN Usage Hey Sherz! (For real!) Cost of LEO Hey Sherz! Who pays for development? Kepler's dream of space travel Mambo Wolfe (was Re: Tom Wolfe's THE RIGHT STUFF - Truth or Fiction?) Mining on the Moon? Moon Base Moon vs. asteroids, Mars, comets More on Comet-Jupiter Collision Reasons for a moonbase. Some numbers for Ken (4 msgs) Welcome to the Space Digest!! Please send your messages to "space@isu.isunet.edu", and (un)subscription requests of the form "Subscribe Space " to one of these addresses: listserv@uga (BITNET), rice::boyle (SPAN/NSInet), utadnx::utspan::rice::boyle (THENET), or space-REQUEST@isu.isunet.edu (Internet). ---------------------------------------------------------------------- Date: 2 Jun 1993 18:39:18 GMT From: Doug Mohney Subject: DSN Usage Newsgroups: alt.sci.planetary,sci.space In article <2JUN199316345831@kelvin.jpl.nasa.gov>, baalke@kelvin.jpl.nasa.gov (Ron Baalke) writes: >In article <1ugf58INNhac@rave.larc.nasa.gov>, s.d.derry@larc.nasa.gov writes... >>How busy is the DSN? > >It is very busy. Here's a list of the spacecraft we've supported in the >past 24 hours: Voyager 1, Voyager 2, Mars Observer, Magellan, Ulysses, >Pioneer 11, Solar-A , Nimbus-7 , Hippocarus, Astro-D, Geotail, Rosat. >Also, some VLBI work was done. You left out the pizza call from Alpha Centauri :-) >>Are things going to get better or worse? >> >Probably worse. I see more spacecraft being launched than dying out. Unless some projects are defunded. Software engineering? That's like military intelligence, isn't it? -- > SYSMGR@CADLAB.ENG.UMD.EDU < -- ------------------------------ Date: 2 Jun 1993 12:20:59 -0700 From: Ken Hayashida Subject: Hey Sherz! (For real!) Cost of LEO Newsgroups: sci.space Source-Info: Sender is really isu@VACATION.VENARI.CS.CMU.EDU aws@iti.org (Allen W. Sherzer) writes about my post: >Amazing. This from the person who has yet to post a single reference or >number in any post. Instead of complaining about the mote in my eye, >you should see to the beam in your own. >May I conclude then that your postings are meaningless since you >don't post references or numbers? No, because I don't make outlandish comments and statements about the cost of the shuttle program or the DC-X. You are the person asserting these budget arguments. I only point out that it is impossible to ascertain the validity of your statements without clear and specific statements detailing the nature of your calcuation. >>I urge you to follow standard science paper procedures in order to support >>your contentions, that means posting references, page numbers, and methods. >I have done so many times in the past. I urge you to follow your own >advice. Your posting has not included references in the past. I would not have initiated this thread if they had. One of your reference lines was something like "presentation before the Augustine Commission." What does that mean? Who said it, where is it published, and what data did they have? >>Allen, do understand what it takes to get three astronauts out on a >>simulataneous EVA? You must! How can you call that unworthy? >As a cost effective operation, it fails. As part of an ongoing program >of research on EVA, it could be justified. The problem is that there >was no such program of space based EVA research. Intelsat was PR, not >practice. Allen, you judge everything by a dollar and cent. If the world operated like that then saving a guys life with a multimillion dollar MRI or CT Scan would be out of the question because you didn't feel it was "cost-effective." In addition, could you please stop trying to put words in my mouth. Asking me why I think DC-Y will fail was uncalled for, especially when you know from my personal letter to you, that I believe DC-X to be a worthy program for government funding. I object to your continuing barrage of attacks on the worthiness of the shuttle program. As for your criticism that I do not post numbers, that will be shortly changing as I complete my report for sci.space. Until then, I ask you friends to please wait. I am not going to post numbers until I can cross reference them in acceptable documentation from within NASA or industry. >If you claim to support spaceflight by men and women, why do you >support this wasteful spending which our opponents use to show >that manned space will never work? I have asked you this question >several times. I note you ignore it every time. I ignore this question because it implies that the work is useless, which it is clearly not. Unless we understand how to fly orbiter, to rendezvous with targets in various orbits, and to perform EVA's in the cargo bay of the orbiter; in my opinion we cannot hope to use DC-whatever for space station work, as you claim. I will be posting my view as to why you are mistaken in your assumption that DC-1 will be useful for that program. Cordially yours, Ken khayash@hsc.usc.edu ------------------------------ Date: 2 Jun 1993 12:36:12 -0700 From: Ken Hayashida Subject: Hey Sherz! Who pays for development? Newsgroups: sci.space aws@iti.org (Allen W. Sherzer) writes: >Talk to the SEC and take an accounting class. Generally, development >costs should be charged to the users. If a technology or part is >amortized, charge fair production costs. >In a nutshell, everything in the Shuttle development budget (or DC >development budget, or any development budget) should be charged to >the users. This creative allocation of costs Shuttle supporters use >to make some missions look a bit cheaper doesn't work. >Governments can do it to us, but they tend to throw you in jail >if you do it to them. There is a fallacy in this argument. The problem is that items which are used by the federal government have only one customer...the fed. So, since the fed is the user, they are the ones who should foot the R&D bill. Your view of shuttle is different than your view of other launch vehicles. I don't hear you complaining about the development costs of the Saturn V, the Titan, the Delta, the Ariane, the Scout, the Redstone, the Saturn 1B, etc. I only hear you complaining about the budget of the shuttle. This is the reason I began posting 1 month ago in order to present an alternative to your "cost is always the bottom line" view. It is short-sighted in my opinion to believe that "customers" will be capable of footing the billion-dollar R&D bill for the creation of a whole new launch system. You are quite vociferous in your support for federal spending on DC-X. If you are so interested in customer supported R&D, could you please explain why you are interested in making the fed fund DC-1? (I reiterate, that I am in favor of fed spending for DC-1 R&D. It's my city's congressman who is sponsoring the DC-1 program language in the House Armed Services Committee.) I had said: >>We are not wasting billions for emotional attachment... >Well then let's see your cost analysis. Show me that the $$ is being >well spent. Apply to yourself the same standards you apply to others >and post the numbers with references. Mr. Sherzer, I am not the person making claims about shuttle's budget. You are. I am only offering valid questions in order to clarify how you reach your conclusions. Simply because I am asking questions, does not imply that I am willing to perform an audit of the shuttle program because you want me to. Since you are the one who claims to have audited the program, you are the one who needs to post the references and methods for your calculations. I will be attempting to locate the book which you refer to...unfortunately it is difficult to do so when you have not stated who published the book and where in the book you got your numbers from. ------------------------------ Date: 2 Jun 93 15:43:09 -0600 From: Bill Higgins-- Beam Jockey Subject: Kepler's dream of space travel Newsgroups: sci.physics,sci.space,rec.arts.sf.written In article <1993May26.041100.17721@galois.mit.edu>, jbaez@riesz.mit.edu (John C. Baez) writes: > I have just begun reading "Kepler's Dream" by John Lear, and while I > haven't gotten too far yet, I highly recommend it to everyone who likes > the little mind-blowing nooks and crannies of history. Kepler's > "Dream," or "Somnium," was a book he died before publishing, and which > seems to have remained fairly obscure. It is written in the form of a > fantasy about space travel, but its subject is apparently mostly lunar > geography. (Selenography, perhaps?) Here's a review I wrote while researching an exhibit for Chicago's Museum of Science and Industry. I've added rec.arts.sf.written to the newsgroup line, since I think the story qualifies as eo-SF. And the kids there are always asking about SF writers who are also scientists... Johannes Kepler's Voyage to the Moon Johannes Kepler (1571-1630) was the astronomer who recognized that the planets move around the Sun in ellipses, a discovery which led directly to the Newtonian revolution which gave us our present understanding of the laws of physics. One of his books, *Somnium* or, in English, *Dream*, is a fictional voyage to the Moon. Duracotus, a native of Iceland, studies astronomy with Tycho Brahe in Denmark. When he returns home he discovers that his mother knows far more about the Moon than Tycho does; she reveals that she is a witch and converses with demons who regularly travel through space. (Kepler studied with Tycho, the greatest astronomical observer of his age, and his mother was once accused of witchcraft and imprisoned.) The witch summons a demon, who explains that travel to the oon is possible only when the shadow of the Earth touches it-- that is, during a lunar eclipse. "Because the opportunity is so fleeting, we take few human beings along, and only those who are most devoted to us. Some man of this kind, then, we seize as a group and all of us, pushing from underneath, lift him up into the heavens. In every instance the take-off hits him as a severe shock, for he is hurled just as though he had been shot aloft by gunpowder to sail over mountains and seas. For this reason at the outset he must be lulled to sleep immediately with narcotics and opiates. His limbs must be arranged in such a way that his torso will not be torn away from his buttocks nor his head from his body, but the shock will be distributed among his individual limbs. Then a new difficulty follows: extreme cold and impeded breathing. "The cold is relieved by a power which we are born with; the breathing, by applying damp sponges to the nostrils. After the first stage of the trip is finished, the passage becomes easier. At that time we expose their bodies to the open air and remove our hands. Their bodies roll themselves up, like spiders, into balls which we carry along almost entirely by our will alone, so that finally the bodily mass proceeds toward its destination of its own accord. But this onward drive is of very little use to us, because it is too late. Hence it is by our will, as I said, that we move the body swiftly along, and we forge ahead of it from now on lest it suffer any harm by colliding very hard with the moon. When the humans wake up, they usually complain about an indescribable weariness of all their limbs, from which they later recover well enough to walk." In this passage Kepler demonstrates that he understands many of the problems of space flight: the need for sudden acceleration, the dangers of its effect on the body, the cold of space, the gradual thinning of the atmosphere, the "onward drive" provided as the Moon's attraction grows. Some of these he must solve by magic, such as the demons' lifting power and warmth. Some he tries to solve by plausible invention-- arranging the passengers' limbs and applying the damp sponges-- just as a modern science fiction writer would. Though *Somnium* was written in 1609, nearly sixty years before Newton published a complete theory of gravity, Kepler evidently knew that planets attracted other massive bodies and that the attraction became weaker with distance. The bulk of the story is concerned with a detailed description of astronomy as seen from the Moon. The Earth hangs fixed in the sky, the Sun arcs slowly overhead every 28 days, eclipses are markedly different from terrestrial ones, and the behavior of the planets is somewhat novel. Kepler evidently delighted in working out the facts of lunar astronomy, and his whole story is carefully consistent with the known facts of seventeenth-century science. He speculates on the effect of long days and nights on life on the Moon. Plants and animals take forms with tough skins to endure the scorching Sun, and the oceans boil at noon. The *Somnium* may be said to be the earliest "hard-science" SF story: one which hews closely to the line of contemporary science. Amusingly, Kepler yielded to a temptation that must have afflicted many a subsequent hard-SF writer-- he added footnotes to explain the meticulously built scientific background to his story. The footnotes run more than four times the length of the story itself! ============ The lengthy quote is from Edward Rosen, ed. and trans., *Kepler's Somnium*, University of Wisconsin Press, Madison, Wisconsin 1967, p. 15. For another translation and further commentary, see John Lear, ed., Kepler's Dream, trans. by Patricia Kirkwood, University of California Press, Berkeley, 1965. -- O~~* /_) ' / / /_/ ' , , ' ,_ _ \|/ - ~ -~~~~~~~~~~~/_) / / / / / / (_) (_) / / / _\~~~~~~~~~~~zap! / \ (_) (_) / | \ | | Bill Higgins Fermi National Accelerator Laboratory \ / Bitnet: HIGGINS@FNAL.BITNET - - Internet: HIGGINS@FNAL.FNAL.GOV ~ SPAN/Hepnet: 43011::HIGGINS ------------------------------ Date: 2 Jun 93 15:05:12 -0600 From: Bill Higgins-- Beam Jockey Subject: Mambo Wolfe (was Re: Tom Wolfe's THE RIGHT STUFF - Truth or Fiction?) Newsgroups: sci.space,rec.arts.books In article , jswan@netcom.com (Jeff Swanson) writes: > You view this sort of book as exactly what it is -- an entirely > subjective account of human foibles and idiosyncracies, run through > the screen of Wolfe's stylistic objectivity. > I love this book. I think it should be required reading > in any good high school/college level writing course. I think that's a bit strong. It might have an unfortunate influence on the writing style of our young men and women. Look what happened to Ed Regis, author of *The Great Mambo Chicken and the Transhuman Condition*. It's a good book, but it would have been better if the poor wretch did not try to write... an *exact* imitation... of TOM WOLFE!!!!! -- O~~* /_) ' / / /_/ ' , , ' ,_ _ \|/ - ~ -~~~~~~~~~~~/_) / / / / / / (_) (_) / / / _\~~~~~~~~~~~zap! / \ (_) (_) / | \ | | Bill Higgins Fermi National Accelerator Laboratory \ / Bitnet: HIGGINS@FNAL.BITNET - - Internet: HIGGINS@FNAL.FNAL.GOV ~ SPAN/Hepnet: 43011::HIGGINS ------------------------------ Date: Wed, 2 Jun 1993 17:28:19 GMT From: Gary Coffman Subject: Mining on the Moon? Newsgroups: sci.space In article <24924@mindlink.bc.ca> Nick_Janow@mindlink.bc.ca (Nick Janow) writes: >henry@zoo.toronto.edu (Henry Spencer) writes: > >> Alas, it's not that easy -- almost anything contaminates titanium. :-) The >> SR-71 project had considerable trouble with the cadmium in the plating on >> ordinary wrenches, as I recall. >> >> Also, there will be plenty of oxygen, since the titanium is already >> intimately associated with it in ilmenite and similar minerals. The >> problem on Earth is getting the last little bit of oxygen *out*, not >> keeping more from getting in. > >Cadmium and other protective coatings won't be required in space. Also, >isn't a significant part of the problems with working titanium due to >forming, welding, or other high-temperature treatments? These problems, at >least, would be eliminated. > >> And titanium is a pain even if contamination is not an issue. It's very >> hard and wears out cutting bits in a shocking hurry. > >Hmmm, since titanium reacts quite happily with carbon, would diamond coated >cutters be useless (except at low speeds)? :-/ The major problems with titanium are simple machining and cutting tasks. The stuff doesn't turn well, it galls and grabs rather than throwing a nice clean chip. It is also refractory and requires inordinate amounts of cooling fluid to prevent burning up the tool points. It still, as Henry says, eats them in a shocking hurry. Welding and underwater explosive forming of titanium are relatively straight forward. You don't heat treat titanium like you do carbon steel, it doesn't form different solid solutions when heated and quenched. >> Unless you really, really need titanium's special properties, aluminium is >> a whole lot less hassle. > >I agree. Also, magnesium is fairly common on the moon, and will be more >useful than on Earth (no corrosion of flammability problems if used >externally). Well, magnesium is highy reactive with many materials. Corrosion would be a problem at dissimilar material joints even without free oxygen to cloud the issue. As Henry says, aluminium is much easier to work, but without an oxygen atmosphere, the normal microscopic aluminium oxide layer won't instantly form, and it will be reactive at dissimilar joints too. Iron is easier still to work and there are asteroids that are nearly pure nickel iron, no refining needed. >There's also the potential for alloys that can be prepared in lunar gravity >but not in Earth gravity, and still more that can be made in zero-g. There >are also alloys that aren't used or even studied much on Earth due to >problems with atmospheric interaction (both in forming and use). Who knows, >calcium alloyed with bismuth and lithium (for example) could turn out to be >an important material. I suspect that any alloy that forms under 1/6 G could also be formed under 1 G by extremely rapid quenching. If you have to allow natural cooling for the desired structure, even 1/6 G would be too high. Gary -- Gary Coffman KE4ZV | You make it, | gatech!wa4mei!ke4zv!gary Destructive Testing Systems | we break it. | uunet!rsiatl!ke4zv!gary 534 Shannon Way | Guaranteed! | emory!kd4nc!ke4zv!gary Lawrenceville, GA 30244 | | ------------------------------ Date: Wed, 2 Jun 1993 18:30:35 GMT From: Gary Coffman Subject: Moon Base Newsgroups: sci.space In article <1993Jun2.051925.4726@ucsu.Colorado.EDU> fcrary@ucsu.Colorado.EDU (Frank Crary) writes: >In article <4238@spikes.mdavcr.mda.ca> gopinath@mdavcr.mda.ca (Gopinath Kuduvalli) writes: >>>Since when are "flags and footprints" and mining the only alternatives? >>>There are many other reasons for long-term of permanent presence, that >>>have nothing at all to do with mining. > >>Pray tell, what *are* these other reasons for long-term permanent presence >>on the moon, mars or wherever in space? > >The completely unacceptable (politically) but most direct answer is, >"Manifest Destiny": The future is not on one, crowded, resource-depleated >world. The Earth is not yet crowded, or resource depleted in any sense that space exploitation will have any impact on. Aside from a few atoms we've fissioned prematurely, and a microscopic amount we've tossed into space, every bit of everything that was here is still here. Energy is still pouring in at the rate of one kilowatt per square meter per second same as it always has. Earth doesn't need imports from space, and exports won't solve any problems. Now that said, Manifest Destiny is still the prime directive for long term space occupancy. Now that we have the capability almost in our grasp, it's foolish to keep all of Mankind's eggs in one little blue basket. When the next dinosaur killer, or whatever, comes, I want at least some of Mankind to be safely elsewhere. Gary -- Gary Coffman KE4ZV | You make it, | gatech!wa4mei!ke4zv!gary Destructive Testing Systems | we break it. | uunet!rsiatl!ke4zv!gary 534 Shannon Way | Guaranteed! | emory!kd4nc!ke4zv!gary Lawrenceville, GA 30244 | | ------------------------------ Date: 2 Jun 93 12:27:46 From: Steinn Sigurdsson Subject: Moon vs. asteroids, Mars, comets Newsgroups: sci.space In article jhart@agora.rain.com (Jim Hart) writes: jthomas@prs.k12.nj.us (Jay Thomas) writes: >And by the way is wrong with self replicating factories. Nothing, in theory. In practice, you have practically no idea how to build one. Unless of course you consider a few NASA Actually we do know one way. You use self-replicating ~75kg automatons, use them to build tools, for self-repair and maintenance and programming of new units for building new factories. Overhead is high but the system has been quite thoroughly debugged and most of the R&D is sunk... :-) | Steinn Sigurdsson |I saw two shooting stars last night | | Lick Observatory |I wished on them but they were only satellites | | steinly@lick.ucsc.edu |Is it wrong to wish on space hardware? | | "standard disclaimer" |I wish, I wish, I wish you'd care - B.B. 1983 | ------------------------------ Date: Wed, 02 Jun 1993 20:40:20 GMT From: Innocent Bystander Subject: More on Comet-Jupiter Collision Newsgroups: sci.space,sci.astro zellner@stsci.edu (BEN) Pontificated: >According to a highly authoritative celestial mechanic who doesn't want >to be quoted yet, the formal probability of an impact between 1993e >Shoemaker-Levy 9 and Jupiter on 1994 July 20 is now 100%. > What a way to celebrate the 25th anniversary of the Apollo 11 landing! /~~~(-: James T. Green :-)~~~~(-: jgreen@trumpet.calpoly.edu :-)~~~\ | "You know how people are. They only recognize greatness | | when some authority confirms it." | | -Bill Watterson in "Calvin and Hobbes" | ------------------------------ Date: Wed, 2 Jun 1993 17:46:12 GMT From: Gary Coffman Subject: Reasons for a moonbase. Newsgroups: sci.space In article <9305282214.AA22661@DPW.COM> tmartin@dpw.com (Thomas Martin) writes: >In the previous discussions there is one reason for constructing a lunar >base that I haven't seen mentioned. Wouldn't learning how to develop a >working PLANETARY environment be easier on the moon if we are planning to >build one on Mars in a few years. I mean, many of the problems would be >the same. Such as the following: > > >Building/Living Environment Moon Mars > ====== ====== >Atmosphere None Extremely low pressure On Mars at least, the atmosphere is sensible and considerable convective cooling could be exploited. Not so the Moon. Also the atmosphere has direct uses when compressed, not so the Moon. >Surface Rocky/Dusty Rocky/Dusty There is known water on Mars, not so the Moon. >Geological activity Minimal Some ? >Weather None Some ? Weather on Mars can be extreme with high winds and planet encompassing dust storms. Couple that with the naturally lower solar flux and the more rapid rotation rate and power systems would need to be seriously different on Mars than the Moon. >It seams to me that we could accomplish many of the objective of the space >station and the future trip to mars with a bas on the moon. Plus, correct >me if I'm wrong, but on the moon, if you are mining materials for >oxygen/construction aren't you creating more living space? > > _____________________________________________ > / \ > / Lunar Surface Base \ >--------------------------------------------------------------------------- > | | > | | > | | > | | > ---------------- ---------------- > | Created Elbow Room | > ------------------------------------- > >Simplistic yes, but realistic? No. It's unlikely that tunnel mining would be common on the Moon, at least until there is a large manned presence there. Control issues become too complex. Most scenarios use surface mining by remote controlled dragline or micro-dozers. Dealing with the debris is difficult to automate in tunnels, and shoring materials aren't common, nor is there the on site expertise to know *where* to place the shoring. Almost nothing that's suited for space station operations is suited for Lunar conditions, and the extra distance and delta-v required to reach the Lunar surface would make regular transport of experiments there extremely costly compared to a LEO station. Offsetting that is only the prospect of Lunar oxygen, and perhaps some refined aluminium. The most interesting experiments usually occur under extreme conditions. The station offers micro-G and hard vacuum. The Moon only offers hard vacuum, and not as hard as that behind a wake shield in LEO. Gary -- Gary Coffman KE4ZV | You make it, | gatech!wa4mei!ke4zv!gary Destructive Testing Systems | we break it. | uunet!rsiatl!ke4zv!gary 534 Shannon Way | Guaranteed! | emory!kd4nc!ke4zv!gary Lawrenceville, GA 30244 | | ------------------------------ Date: 2 Jun 93 12:23:41 From: Steinn Sigurdsson Subject: Some numbers for Ken Newsgroups: sci.space In article <1993Jun2.170008.24760@iti.org> aws@iti.org (Allen W. Sherzer) writes: Well to help Ken out I dug out my spreadsheets and plugged in some new DC numbers which recently came my way. I will present two models which show expected vs worse case. The worse case is in essence the best case times two. Both models assume a production run of four DC-1's and a total launch rate of 200 flights per year for the fleet. DDT&E is amortized over ten years at an interest rate of 8%/year. The numbers are: DDT&E Launch Cost Total Cost Payload $/LB to LEO $5B $6M $9.63M 24,000 LB $401 $10B $12M $19.26M 20,000 LB $963 Worse case SSTO numbers are still fully ten times cheaper than Shuttle. We could even cut the flight rate in half and beat Shuttle by a factor of Nice numbers. Can you really get 8% on something this risky? And what the hell are you guys planning to launch @200/year!? (yeah, I know, this cheap you make a market for yourself...) I still think your launch costs are optimistic, way optimistic, but I guess there's only one way to find out if that rate and cost can be achieved ;-) | Steinn Sigurdsson |I saw two shooting stars last night | | Lick Observatory |I wished on them but they were only satellites | | steinly@lick.ucsc.edu |Is it wrong to wish on space hardware? | | "standard disclaimer" |I wish, I wish, I wish you'd care - B.B. 1983 | ------------------------------ Date: 2 Jun 1993 12:46:38 -0700 From: Ken Hayashida Subject: Some numbers for Ken Newsgroups: sci.space aws@iti.org (Allen W. Sherzer) writes: >Well to help Ken out I dug out my spreadsheets and plugged in some new >DC numbers which recently came my way. I will present two models which >show expected vs worse case. The worse case is in essence the best case >times two. Both models assume a production run of four DC-1's and a total >launch rate of 200 flights per year for the fleet. DDT&E is amortized ^^^^^^^^^^^^^^^^^^^^ >over ten years at an interest rate of 8%/year. The numbers are: >DDT&E Launch Cost Total Cost Payload $/LB to LEO > $5B $6M $9.63M 24,000 LB $401 >$10B $12M $19.26M 20,000 LB $963 >Now, let's compare this to Shuttle. To make Ken and Dennis happy we will >pretend that design and development of Shuttle where free. We will also >pretend that absolutely NO interest was charged to anybody (which only >seems fair since we are pretending the whole thing was free anyway). All >we will do is take what is spent on Shuttle every year and divide by the >flight rate. This gives us a per flight cost of over half a billion $$ >per flight and over $10,000 per pound to LEO (two to three times the cost >of expendables). >So what's the problem Ken? The problem is two fold. Number one, you failed to tell me where your numbers are coming from, if you had, then your post would have been unstoppable. Number two, you still have never made a detailed post with how you are calculating your shuttle launch costs. Number 3, your estimates of DC-1 flight rates seem awfully high. 200 flights per year comes to 4 flights per week. I can't imagine any government needing a flight rate that high. What are we flying 200 times per year? Tourists? Can anyone out there tell me if the entire world sends 200 rockets into orbit per year? ------------------------------ Date: Wed, 2 Jun 1993 20:40:44 GMT From: "Allen W. Sherzer" Subject: Some numbers for Ken Newsgroups: sci.space In article steinly@topaz.ucsc.edu (Steinn Sigurdsson) writes: > DDT&E Launch Cost Total Cost Payload $/LB to LEO > $5B $6M $9.63M 24,000 LB $401 >Nice numbers. Thanks. >Can you really get 8% on something this risky? Full faith and credit of the US is backing it so I think so. But to address this I tried it with 12% interest. Cost per launch went up by $660,000 per flight (about 10%), still far cheaper than the competition. >And what the hell are you guys planning to launch @200/year!? >(yeah, I know, this cheap you make a market for yourself...) It would make the market a lot bigger that's for sure. I was thinking we could launch science experiments on the extra flights. After all, we can launch a DC-1 200 times for just about what it costs us to launch Shuttle eight times. >I still think your launch costs are optimistic, way optimistic, Could be. On the other hand, they can be off by quite a lot and it's still a good idea. If we account for costs the way Ken and Dennis do, it can cost 20 to 40 times as much and STILL be cheaper than Shuttle. >but I guess there's only one way to find out if that rate >and cost can be achieved ;-) Yep. Of course, if it doesn't work, we will know LONG before we build the DC-1. Allen -- +---------------------------------------------------------------------------+ | Lady Astor: "Sir, if you were my husband I would poison your coffee!" | | W. Churchill: "Madam, if you were my wife, I would drink it." | +----------------------14 DAYS TO FIRST FLIGHT OF DCX-----------------------+ ------------------------------ Date: Wed, 2 Jun 1993 20:51:00 GMT From: "Allen W. Sherzer" Subject: Some numbers for Ken Newsgroups: sci.space In article <1uj02u$6b5@nml1sun.hsc.usc.edu> khayash@nml1sun.hsc.usc.edu (Ken Hayashida) writes: >>So what's the problem Ken? >The problem is two fold. Number one, you failed to tell me where your >numbers are coming from, SDIO. >if you had, then your post would have been unstoppable. Well that takes care of that! >Number two, you still have never made a detailed post >with how you are calculating your shuttle launch costs. I have several times Ken. It's quite simple. You add up the Shuttle line items in the federal budget and divide by the flight rate. If you do, you will come up with a number larger than $500M per flight. Note that this does not include DDT&E or interest. If we did, the cost of a flight would go to well over $1B per flight. >Number 3, your estimates of DC-1 flight rates seem awfully high. We will know better by the end of the year, but it looks like that is attainable with a four ship fleet at the moment. >200 flights per year comes to 4 flights per week. Not quite. I gave each vehicle two weeks off in the summer for vacation. >I can't imagine >any government needing a flight rate that high. I'm not supprised. For what we spend to fly Shuttle eight times we could launch DC 200 times. Let's use the extra flights to do more science? Is that OK with you? >What are we flying >200 times per year? Tourists? At DC prices, that becomes a real posibility. Better still, unlike Shuttle, the economics of SSTO are linear. The more you fly, the cheaper it gets. Allen -- +---------------------------------------------------------------------------+ | Lady Astor: "Sir, if you were my husband I would poison your coffee!" | | W. Churchill: "Madam, if you were my wife, I would drink it." | +----------------------14 DAYS TO FIRST FLIGHT OF DCX-----------------------+ ------------------------------ End of Space Digest Volume 16 : Issue 662 ------------------------------