Date: Tue, 29 Dec 92 05:15:12 From: Space Digest maintainer Reply-To: Space-request@isu.isunet.edu Subject: Space Digest V15 #606 To: Space Digest Readers Precedence: bulk Space Digest Tue, 29 Dec 92 Volume 15 : Issue 606 Today's Topics: "Slick" Goodlin Acceleration Aluminum as rocket fuel? Dante Advisory Denver NASA Meeting How much radiation can an organism survive? (Panspermia) Justification for the Space Program (5 msgs) Manhattan DISTRICT (not Pr......) satellite costs etc. Shuttle costs vs DC costs Stupid Shut Cost arguements Stupid Shut Cost arguements (was Re: Terminal Velocity 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: 29 Dec 92 03:37:00 GMT From: SNOMCB Subject: "Slick" Goodlin Newsgroups: sci.space Just out of curiousity can anyone tell me whatever happened to Chalmers "Slick" Goodlin? Cannot seem to find anything about him after his hot shot days at Muroc, aka Edwards AFB. Mike Bishop SAS Institute Inc. Cary NC ------------------------------ Date: Mon, 28 Dec 92 22:35:07 EST From: John Roberts Subject: Acceleration -From: prb@access.digex.com (Pat) -Subject: Re: Acceleration -Date: 27 Dec 92 18:04:22 GMT -Organization: UDSI -In article <1992Dec22.220405.26976@wuecl.wustl.edu> gene@wucs1.wustl.edu (_Floor_) writes: ->In article roberts@cmr.ncsl.nist.gov (John Roberts) writes: ->] That applies to things that are somewhat resiliant (like humans with their ->] limbs not locked), because if deformation continues throughout the period ->] of acceleration, then the entire body is not really subjected to the full -> ->Hmmm...you think maybe rigidity has something to do with this? ->If something is rigid, it is much more likely to break than something ->flimsy, which will bend. Electronics certainly canot be built in ->a manner that will bend. Any flexing of the probe would have to ->be somehow accounted for in the design. -Certainly electronics can be built to be flexible, it's just what degree -of flexibilty you desire. Flex is a stress/strain relationship. -Steel is flexible, rubber is rigid. you just need to define these terms -first. besides, if you build with amorphous materials, you can get -quite a flex out of silicons. Are the solar panels of HST made of amorphous silicon? They were rolled up very tightly before deployment. Something that didn't get adequately covered in the previous posts: in both mechanical and electrical systems, there's a significant difference between *being able to survive* a period of high acceleration or intense vibration, and *continuing to operate* during that period. The hard disk drives in the laptop computers used in the Shuttle generally survive the vibrations of the launch, but they're not expected to run during that time. If an electrical system uses spring-loaded contacts, an intense shock may cause the contacts to open momentarily. I just got some literature from a company at the Technology 2002 conference that makes metal-on-silicone contacts that are rated for 50 G - there may be other kinds of contacts for more demanding situations. Come to think of it, the components I'd worry about the most are the oscillators - anybody know if it's possible to make quartz crystal oscillators sturdy enough to continue working under an acceleration of thousands of gravities? -and i believe the designers understnad the material characteristics -of their probes quite well. I'm inclined to agree - the Galileo atmospheric probe's designers must have considered acceleration and vibration in their design. ->] But other than that, and factors such as prolonged stress on human hydraulic ->] systems, the greater problem can be with rapid changes in acceleration, which ->] are of course associated with short bursts of acceleration. (I believe the ->] usual term for the time derivative of acceleration is "jerk".) These rapid -Actually, i think the term is Impulse. You inspired me to look it up in a reference book: # impulse [MECH] the integral of a force over an interval of time. # jerk [MECH] the rate of change of acceleration; it is the third derivative of position with respect to time. (from the McGraw-Hill Dictionary of Scientific and Technical Terms, 1989) ->You're joking me if you think the Galileo probe will experience constant ->deceleration. There's going to be buffeting worse than we could imagine, ->I imagine (:-). Especially at speeds many times that of sound (which I'm ->sure will be different for the Jovian atmosphere)! So you're point is ->very applicable. Experiencing this jolting for milliseconds (as per ->a dropping watch) may not cause any damage. But if you dangled the watch ->from the ceiling and proceeded to place a jackhammer at its face, ->slamming into its face for a couple of minutes, liklihood is that ->the watch will no longer function! Ditto for an atmospheric probe. ->That thing is going to get one whale of a beating. You've helped me ->emphasize my point even more! Thanks :-) -Hopefully this kid will take a physics class. -I think he is mistaking Work with Force and energy. I think he's introducing the concept of cumulative damage where it might not be applicable. If the magnitude of the forces and the margins of the design are such that there is some cumulative damage (i.e. fatiguing of components that flex slightly), the system could still be designed so that it's likely to survive days or months of such conditions. That's another design parameter that can be tested prior to launch. -Work is force through a distance, Energy is work*time, Force is mass*Accel -( boy i hope i got these right :-) ) You got work and force right, but energy is power * time. Energy is the generic term, while work, heat, etc. are alternate ways of expressing it. They can all be expressed in the same derivative SI units (joules, for instance). Power is energy (work, heat flow, etc.) divided by time. Joules are kg * m^2 / s^2. Watts (power) are kg * m^2 / s^3. It should be noted that in some calculations, "per unit time" or "per unit area" or "per unit mass" is taken for granted, and is implicit in the expression of the problem. That's just a shorthand notation, to avoid having to carry the units through all the calculations. -It takes energy to achieve a momentum change. -A probe has high momentum hitting atmosphere. it gets a high acceleration, -on a small mass. not a lot of force, exerted through several miles of -atmosphere, for a few minutes. -I think the kid is missing the fact that while the accelerations of dropping -a watch and hitting it with a sledge are the same, the work products are significantly different. If you smash the watch between two objects, then college-freshman-type mechanics is no longer a good way to describe the system. All sorts of complex materials properties start to come into play. -Try this. drop a timex. work out the acceleration. You have to make a guess at the degree of deformation, which is very nontrivial. If you assume no deformation, then the peak acceleration comes out infinite. -Now, hang the timex from a string. Let a pendular mass strike it, at low spe -ed. work out the acceleration. keep increasing the mass and speed. -continue until the timex dies. I suspect you will be surprised at how -high you can go. Same problem. You might be able to work out a lower limit for peak acceleration, accepting that the peak is probably *much* higher than this lower limit. John Roberts roberts@cmr.ncsl.nist.gov ------------------------------ Date: Mon, 28 Dec 92 22:48:54 EST From: John Roberts Subject: Aluminum as rocket fuel? -From: juan@hal.COM (John Thompson Reynolds) -Subject: Aluminum as rocket fuel? -Date: 28 Dec 92 14:36:43 GMT -Organization: HaL Computer Systems, Inc. (Appropriate last name for such a question. :-) :-) -I've seen references in the past which suggest using Lunar O2 and Aluminum -as rocket fuels. Have there been any fairly detailed designs of how such -a beast would be constructed? Perhaps a hollow cylinder of packed Aluminum -dust into which LOX is pumped? Here's the only fairly solid reference I've come across. If you could contact the company and post some information, the readers of sci.space would be very grateful. An aluminum-oxygen engine could potentially be very useful for launch from the moon, since both materials are abundant there (and hydrogen is at best very rare, and therefore valuable). I expect the specific impulse isn't too great, but you don't need a very high specific impulse to escape from the moon. -------------------------------------------------------------------- >From: freed@nss.FIDONET.ORG (Bev Freed) Newsgroups: sci.space Subject: Toward 2001 - 02 Dec Message-ID: <1868.293C0AA9@nss.FIDONET.ORG> Date: 3 Dec 91 02:05:21 GMT Organization: The NSS BBS, Pittsburgh PA (412) 366-5208 *********** TOWARD 2001 *********** Week of 2 December 1991 -------------------------------------------------------------------- This information is reproduced by permission of the Space Age Publishing Company. All rights reserved. Copyright December 2, 1991... ==================================================================== * * * * * * * + Wickman Space and Propulsion Sacramento CA Lunar soil broken down into liquid oxygen and aluminum powder powers a new engine being developed by Wickman engineers. A subscale engine has been sucessfully tested for periods of up to 35 seconds at varying levels of thrust. * * * * * * * -------------------------------------------------------------------- John Roberts roberts@cmr.ncsl.nist.gov ------------------------------ Date: 28 Dec 92 21:16:00 GMT From: Ron Baalke Subject: Dante Advisory Newsgroups: sci.space,alt.sci.planetary,comp.robotics Charles Redmond Goddard Space Flight Center, Greenbelt, Md. December 28, 1992 (Phone: 301/286-6256) DANTE ADVISORY ROBOT AND TEAM ARRIVE SAFELY AT MT. EREBUS BASE CAMP Dante, an 8-legged NASA Robot, and the twelve member government/university team undertaking the robotic exploration, have arrived safely at the base of the live Antarctic volcano, Mt. Erebus. The team has successfully established telecommunications between themselves and the Goddard Space Flight Center via the NASA Tracking and Data Relay Satellite. There is the possibility the Antarctic team might be able to transmit at 4:20 p.m. and at 5:30 p.m. EST today video of their preparation activities taped during the past several days. When Dante begins its descent into the crater of the volcano, the team will provide live video during several 20- minute feeds a day. These feeds will occur during 8:00 am and 4:00 pm. The earliest the team estimates the descent will occur is no sooner than Wednesday, Dec. 30. There is no current estimate of the time of these feeds. Also, local weather is a factor and the team is taking longer than orginally expected to accomplish certain tasks, so the estimate of Wednesday could be early. The robot's exploration down the steep inner rim of Mt. Erebus to the lava lake of the Antarctic volcano is a technology demonstration and science expedition between NASA and the National Science Foundation. For most of the robot's expected exploration activities, it will be under the local control of the Antarctic team. However, portions of the robot exploration will be controlled from a payload control center at Goddard. This will be the longest distance ever for live robotic control and simulates what may be in store for NASA's further exploration activities with humans and robots on Mars. Carnegie-Mellon University and the New Mexico Institute of Mining and Technology are partners with NASA and the NSF as robotics and volcano experimenters. Robotic exploration of the live Mt. Erebus volcano will take a minimum of 3 days. Each day, the Antarctic team expects to transmit five 20-minute live video feeds from cameras mounted atop the robot or from atop rim of the volcano. The feeds will be transmitted from Mt. Erebus via NASA's Tracking and Relay Data Satellite West to Goddard. NASA will issue further media advisories when the dates and times of the feeds are known. (Call 301/286-6397 for recorded update information.) NASA also will provide commentary on the robot's progress provided by robotics and volcano experts at Goddard. The television feed and commentary will be available both at Goddard and on NASA Select Televison. -end- ___ _____ ___ /_ /| /____/ \ /_ /| Ron Baalke | baalke@kelvin.jpl.nasa.gov | | | | __ \ /| | | | Jet Propulsion Lab | ___| | | | |__) |/ | | |__ M/S 525-3684 Telos | Choose a job you love, and /___| | | | ___/ | |/__ /| Pasadena, CA 91109 | you'll never have to work |_____|/ |_|/ |_____|/ | a day in your life. ------------------------------ Date: 28 Dec 92 23:07:43 GMT From: Jeff Stoner Subject: Denver NASA Meeting Newsgroups: sci.space,sci.astro In recent postings by Ron Baalke of the Space Calendar, there's a "NASA Town Meeting" listed for Denver, Colorado in January 1993, with no other information or specific date. Does anyone else know more about this? I'm especially interested since I live in the area. Thanks! -- ====== Jeff L. Stoner === Boulder, Colo. ============ /\ = /\ ========== | /\ / \ / /\ /\ --*-- Home: jls2 @ bearhug.boulder.co.us /\/ \/ / / \/ /\ | News: jls2 @ csn.org /\/ \ \ /\ / \ /\ ------------------------------ Date: 28 Dec 92 22:58:41 GMT From: "David M. Palmer" Subject: How much radiation can an organism survive? (Panspermia) Newsgroups: sci.space,sci.bio,sci.med.physics The Panspermia hypothesis is that after life originates on one planet (or in a molecular cloud, or whatever) it can be transported by natural causes to other planets, so that life need be created only once per galaxy (or universe) in order to become widely distributed. People have found that microbes of some sort, when ensporulated (is that the right word? dormant anyway) are very resistant to radiation, and thus could make the trip from star to star, enter a sterile but nutritious environment, and start living, reproducing, evolving and generally creating a biosphere. I personally don't believe that this happens very often, but it's an intriguing idea. Anyway, does anyone have a reference for the work on the microbe spores? I am interested in exactly how much radiation these things can take. Thanks in advance. -- David Palmer palmer@alumni.caltech.edu ------------------------------ Date: Mon, 28 Dec 1992 22:32:26 GMT From: "Dr. Norman J. LaFave" Subject: Justification for the Space Program Newsgroups: sci.space,talk.politics.space In article <1992Dec28.204243.7616@cs.rochester.edu> Paul Dietz, dietz@cs.rochester.edu writes: >Since your reasoning seems inherently incapable of being disproved, >even if wrong, I don't see that it has any value. My arguement has the benefit of centuries of historical precedent which is more than your "There will never be benefits worth the expense" arguement you are spouting which can be easily argued against using the same historical information. Can I prove my assertion? No. However, neither can you prove the contrary. The overwhelming number of historical accounts which support my point makes the effort of space exploration worth the risk. I would rather be bold and take risks in the hope of expanding my horizons than sit around dumb, happy, and complacent while we slip into decline. Let me clue you into something....there are many phenomena in this world, which appear to be true due to overwelming evidence, which are neither well-understood or structured enough to be "proven". A given phenomenon is believed to be true because either a.) The phenomenon always occurs, or b.) The phenomenon happens the vast majority of the time, or c.) It can be rigorously proven to be true. Choice c.) may be superior to the other two, but it is not the only method which defines "belief of validity". Indeed, most of our experimental science is based on a.) and b.) for its foundation. >Theories have to be >falsifiable to be useful. Untrue. Theories need only be logical, and self-consistent with experience, to be useful. Theorists develop and study theories that lack definitive proof all the time. >In practice, you *will* have to argue that >a project has specific benefits or it will not be funded (or, rather, >you won't get funded for your *next* project, as with Apollo). And this is what is wrong with the whole system. Hundreds of examples of pure science leading to unforeseen applications and unheard of prosperity are ignored in favor of safe, incremental development which barely keeps our economic head above water. This is not the way our society became great. Taking risks use to be the ideal in this country and lead to our greatest achievements and our economic and technical superiority. We have lost these benefits due to our timidity and lack of foresight. > >You mention comsats, etc.: yes, but that has little to do with the >Club of Rome/wild schemes of space resource exploitation that started >this thread. Satellite communication was once thought of as wild fantasy too. Surely you have more perspective than this. You are only making my point for me. >Moreover, these benefits were not unpredicted: Clarke >forecast geostationary communication relays in 1947. Clarke was a visionary, as has been many science fiction writers (Jules Verne, Micheal Crichton, H. G. Wells,...). The predictions of a science fiction writer may indeed come true, but they are not the same as the predicitons of engineers and scientists in their same field of endeavour. Furthermore, this does not negate the fact that benefits are already here that short-sighted people like you would have killed before fruition if you had been allowed to do so. You would have claimed that communication by satellite was a "Club of Rome/wild scheme" and dismissed it as the ravings of "zealots" (I'm a zealot too!!). Paul, we have been round-and-round about this before.... I suggest that you are in dire need of a history of science and technology course or need to read the writings of the great scientists to know how little they understood the awesome potential of their discoveries. Dr. Norman J. LaFave Senior Engineer Lockheed Engineering and Sciences Company When the going gets weird, the weird turn pro Hunter Thompson ------------------------------ Date: Mon, 28 Dec 1992 19:09:41 GMT From: Mike Kirby Subject: Justification for the Space Program Newsgroups: sci.space In article 1305@cs.rochester.edu, dietz@cs.rochester.edu (Paul Dietz) writes: >In article <1992Dec28.152258.23834@aio.jsc.nasa.gov> Dr. Norman J. LaFave writes: >>In article <1992Dec27.205945.25241@cs.rochester.edu> Paul Dietz, >>dietz@cs.rochester.edu writes: > > >The differences between the age of exploration and today are >considerable. The raw mineral and agricultural products (and slaves) >that profited the explorers of that age are a much smaller fraction of >GDPs today. > >More generally, arguments by analogy are essentially circular. You >have to assume that the analogy is valid to believe the argument. I >don't see any reason to do that here. There are contrary analogies: >for example, exploration of Antarctica has been of little practical >benefit to the exploring countries (although it has been of scientific >benefit to humanity as a whole). > > Paul F. Dietz > dietz@cs.rochester.edu It seems that a reasonable justification for space exploration is simply that. It is there. Your analogy of Antarctica is very relevant. Although it has not been a great financial success, it has been of scientific benefit. By that same argument exploration of space could give us the same scientific benifit. Similarly, exploration of the deep seas is of little economic benifit, but scientifically it allows us to learn more about our planet. So. The original question was should we spend tax-payer money to explore space. I think paul has given us the answer. That answer is yes. We can spend taxpayer money to explore for scientific research. However, taxpayer money should not be spent to help to government extract economic advantages from space. (which is reasonable, that is what private industry is supposed to do). Perhaps we should form a government agency that is responsible for the development and exploration of the scientific aspects of space. Gasp, Could that be NASA? But aren't they a commercial satellite launch company? In all seriousness, it does seem that NASA has strayed a little from what their charter was originally intended to provide. Perhaps a manned space station is a good thing to have, but its sole purpose should be technical innovation and research and development. Not Economic development. Mike Kirby Xerox Corp E-mail: kirby.roch803@xerox.com ------------------------------ Date: Tue, 29 Dec 1992 01:17:35 GMT From: Paul Dietz Subject: Justification for the Space Program Newsgroups: sci.space,talk.politics.space In article <1992Dec28.223226.12849@aio.jsc.nasa.gov> Dr. Norman J. LaFave writes: > My arguement has the benefit of centuries of historical precedent > which is more than your "There will never be benefits worth the > expense" arguement you are spouting which can be > easily argued against using the same historical > information. Can I prove my assertion? > No. However, neither can you prove the contrary. Let me try this again: your historical argument is just bullshit. The reasoning is vacuous, independent of the truth of the conclusion. There are too many differences between then and now to accept the argument as anything more than sloganeering. For example: (1) the vessels they used to explore were straightforward extensions of known technology, (2) the lands explored did not involve significant differences in technology in order to survive [those that did, like the high Artic, were left largely alone for centuries], (3) the resources they found could be exploited at low cost and yet returned benefits large in proportion to the size of their economies. These conditions don't appear to apply to space. The track record so far in space is that some limited automated applications are useful, or profitable (comsats are profitable, at least for the moment; the others are government-run, so we don't know if they really would be profitable.) Space resources? We went to the moon and found... very little of practical value. Space manufacturing? Endlessly hyped with little to show for it. Microgravity research? Impartial scientific review says it isn't worth much. You advance the straw man argument that I am arguing that there will never be any benefits. As you say, we can't know that. But lack of certainty doesn't mean we are absolved from the need to make decisions on how scarce funds are expended. You can't just say "you can't prove me wrong, so gimme." At least, not with a straight face. Paul F. Dietz dietz@cs.rochester.edu ------------------------------ Date: 29 Dec 1992 02:07:12 GMT From: Randall Tyers Subject: Justification for the Space Program Newsgroups: alt.rush-limbaugh,talk.politics.space,sci.space In article <1992Dec23.110509.22141@ke4zv.uucp> gary@ke4zv.UUCP (Gary Coffman) writes: [...] > >Large scale imports from space face a dire problem in any event. What >are we going to do with all that extra mass? Earth's gravitational >field will so increase that no one will be able to stand if we bring >in too much from space. Ultimately we have no choice but to use and >reuse the materials here on Earth. Fortunately that is getting easier >and easier as technology advances. > >Gary If this was a joke (it has to be right?? doesn't it?) you should have indicated this in some manner. (eg. :-) or ;-) ) As your statement stands it raises doubts about your comprehension of very basic physics. A table tells me that the mass of the earth is ~6x10^22 tons! If I recall corectly the formula for the strength of a gravitational field is g=GMe/Re^2 where e stands for earth thus the surface gravity of the planet increases in direct proportion to its mass ie g is proportional to M. Thus to get a 1% increase in g you would need to increase the mass of the earth by 1% or 6x10^20 tons. This would be a rather ambitious project :-) and a 1% increase in g probably wouldn't be a major problem anyway. Randall Tyers ------------------------------ Date: 29 Dec 92 00:29:05 GMT From: John McCarthy Subject: Justification for the Space Program Newsgroups: alt.rush-limbaugh,talk.politics.space,sci.space Let me add to the previous post the estimate that the total amount of matter humanity has processed in its history is less than 10^12 tons. -- John McCarthy, Computer Science Department, Stanford, CA 94305 * He who refuses to do arithmetic is doomed to talk nonsense. ------------------------------ Date: Mon, 28 Dec 1992 21:13:31 GMT From: Steve Jenkins Subject: Manhattan DISTRICT (not Pr......) Newsgroups: sci.space As long as we're being pedantic, the name was Manhattan Engineering District. Nothing whatever hinges on the name. Everyone knows exactly what the term "Manhattan Project" denotes. -- Steve Jenkins jenkins@devvax.jpl.nasa.gov Caltech/Jet Propulsion Laboratory (818) 306-6438 ------------------------------ Date: Tue, 29 Dec 1992 03:27:15 GMT From: Henry Spencer Subject: satellite costs etc. Newsgroups: sci.space In article <1992Dec27.163935.20473@ke4zv.uucp> gary@ke4zv.UUCP (Gary Coffman) writes: >>...assumption, not a self-evident fact. Communications networks >>normally have redundancy to cover predictable single-point failures. >>Even today's gold-plated satellite networks do, despite the expense. > >It's the network reconfiguration costs that get you. When NBC had to >reconfigure from K2 to SBS 3 due to a control failure on K2, it cost >NBC $150,000 a *minute* for 4.5 hours until the major ground systems >were re-aimed... Doing it *unscheduled* because of >a failure of the cheapsat, can be really expensive if it only happens >once. Why do you assume that the redundancy will involve repointing? If you *plan* for such handovers, you can put the spare satellite in the same orbital slot as the operational one. (Those slots are over a thousand kilometers wide, there's plenty of room.) Result, no repointing. Only the control room needs to even *know* which bird is live. >>>... and since for most orbits >>>the satellites aren't retrievable or repairable, and DC won't change >>>that... >>Again, your assumption, not a self-evident fact. Cheap launches change >>almost everything, including the feasibility of retrieval and repair. > >I wasn't aware that DC was planned to have a GEO capability, or a large >enough cargo bay to retrieve a major comsat. Why do you assume that DC alone has to do everything? The big expense of doing most anything in space is getting into LEO; cutting that cost massively makes *everything* more feasible. It becomes much more attractive to develop a tug capable of bringing things back down from GEO, or a reentry capsule capable of landing a payload too big for a DC cargo bay. Neither of these devices is technologically difficult; they don't exist at the moment because operations costs -- mostly the cost of launching to LEO -- are too high. -- "God willing... we shall return." | Henry Spencer @ U of Toronto Zoology -Gene Cernan, the Moon, Dec 1972 | henry@zoo.toronto.edu utzoo!henry ------------------------------ Date: Mon, 28 Dec 92 23:03:35 EST From: John Roberts Subject: Shuttle costs vs DC costs -From: aws@iti.org (Allen W. Sherzer) -Subject: Re: Stupid Shut Cost arguements (was Re: Terminal Velocity -Date: 28 Dec 92 15:46:24 GMT -In article <72482@cup.portal.com> BrianT@cup.portal.com (Brian Stuart Thorn) writes: -> You seem to have two sets of measuring systems at work. One which you -> use for DC, Titan, Delta et al, and one which you use for Shuttle. -I disagree; I feel I am working very hard to account for both the same -way. -However, if you disagree, please post your own numbers. State the rules -you want to use and apply to both systems fairly. Then show that Shuttle -is better. I tend to agree with you, but you keep factoring initial development cost into cost of using the Shuttle. While that may be interesting in itself, it's not really relevant to the question of whether DC should be developed. The cost of developing DC *is* relevant. As I said before, it's not a "level playing field", but that's the goal DC has to meet - development costs plus operational costs of DC, versus just the operational costs (including any *future* development costs) of the Shuttle. If it wasn't felt that this is possible, nobody would be working on DC. John Roberts roberts@cmr.ncsl.nist.gov ------------------------------ Date: Mon, 28 Dec 1992 22:35:35 GMT From: Donald Lindsay Subject: Stupid Shut Cost arguements Newsgroups: sci.space aws@iti.org (Allen W. Sherzer) writes: >Can you name a product ever made by a successful company which DIDN'T >keep track of product development costs (as opposed to pure research) >and assign those costs to the product? Outside government, you won't. Hmmm. I remember hearing that Xerox bought SDS for a billion dollars - this would be about 1970. I heard later that Xerox had paid about twice what it was worth. Apparently SDS had been taking R&D costs and writing them into the books as assets, ie as if it had purchased capital equipment with the money. -- Don D.C.Lindsay Carnegie Mellon Computer Science ------------------------------ Date: Mon, 28 Dec 92 21:38:08 PST From: Brian Stuart Thorn Subject: Stupid Shut Cost arguements (was Re: Terminal Velocity Newsgroups: sci.space >However, if you disagree, please post your own numbers. State the rules >you want to use and apply to both systems fairly. Then show that Shuttle >is better. > >I await your reply. > > allen Now I'm totally confused, Allen. Wasn't this discussion about the Shuttle's launch rate? I thought that you previously belittled a 25% increase in launch rate, to which I took exception. It was this dual-scale measuring (one for Shuttle, one for the others) that I am complaining about. I'm still waiting for your explanation as to why 25% is a good increase for one, but not another. And by the way, I don't seem to be alone in the opinion that 12 per year is a more likely maximum safe launch rate. That's a 50% increase. Hopefully, the next few months will prove that they can launch monthly if they wanted and politics permitted. In any case, since Shuttle is the only U.S. system flying that can take people to and from space, and is the only system presently capable of returning 30,000+ lbs. of cargo, it is very difficult to compare Shuttle with the expendables (although I think it compares favorably to Titan IV in terms of annual costs versus annual launch rate.) All ratings show Shuttle to be the most powerful launch system in the free world. Depending upon whom you ask, it's either alot more capable than Titan, or just a little. Only the DC is presently envisioned to have more or less the same attributes as Shuttle, and we both know there is no way Shuttle can ever compare favorably to a paper launch system. Pegasus was new and revolutionary too, and it has spent the past eighteen months sitting in an assembly plant. TSS was new and revolutionary, but was brought to its knees by a mislocated bolt. Titan IV was a relatively low-level expansion of current technology, but was a year late off the pad and has flown at a rate one-fourth of the proposed schedule. GD did a relatively minor design change on the Centaur to accomodate greater payload, and it has since failed in flight twice. Shuttle has had all these problems, and more. Gary and I say similar bugs will afflict the DC program, but you tell us not to worry and then call us pessimists. Hmph. -Brian P.S., Sorry about the multiple posts of my previous message in this thread. PortalX crapped out on me in the middle of message uploading. ------------------------------------------------------------------------- Brian S. Thorn "If ignorance is bliss, BrianT@cup.portal.com this must be heaven." -Diane Chambers, "Cheers" ------------------------------------------------------------------------- ------------------------------ End of Space Digest Volume 15 : Issue 606 ------------------------------