Return-path: X-Andrew-Authenticated-as: 7997;andrew.cmu.edu;Ted Anderson Received: from hogtown.andrew.cmu.edu via trymail for +dist+/afs/andrew.cmu.edu/usr11/tm2b/space/space.dl@andrew.cmu.edu (->+dist+/afs/andrew.cmu.edu/usr11/tm2b/space/space.dl) (->ota+space.digests) ID ; Tue, 14 May 91 01:39:23 -0400 (EDT) Message-ID: <4c=rU5W00WBwM3uE4e@andrew.cmu.edu> Precedence: junk Reply-To: space+@Andrew.CMU.EDU From: space-request+@Andrew.CMU.EDU To: space+@Andrew.CMU.EDU Date: Tue, 14 May 91 01:39:17 -0400 (EDT) Subject: SPACE Digest V13 #542 SPACE Digest Volume 13 : Issue 542 Today's Topics: Saturn V's reborn Re: Launch Costs XXIV -- Wright Bros. Flyer to carry tanks to Kuwait! Regarding terraforming Re: Saturn V and the ALS near-station maneuvering Re: Launch Costs Re: Hypersonic Transport Administrivia: Submissions to the SPACE Digest/sci.space should be mailed to space+@andrew.cmu.edu. Other mail, esp. [un]subscription requests, should be sent to space-request+@andrew.cmu.edu, or, if urgent, to tm2b+@andrew.cmu.edu ---------------------------------------------------------------------- Date: 10 May 91 01:28:04 GMT From: ucivax!p4tustin!ofa123!David.Anderman@ucbvax.Berkeley.EDU (David Anderman) Subject: Saturn V's reborn The Saturn V was probably the greatest rocket ever built. It would cost several billion $ to get them flying again, and probably over $1 billion per launch. The question is: why resurrect the Saturn V? I can think of few, if any, real need for the vehicle at this time. Also, if you're going to go to all the trouble to retool, why not spend a little extra and get more performance. For example, why not parallel stage the vehicle, and use existing shuttle pads, rather than build all-new facilities (or convert existing shuttle pads back to Saturn specifications)? -- David Anderman Internet: David.Anderman@ofa123.fidonet.org Compuserve: >internet:David.Anderman@ofa123.fidonet.org -------------------------------------------------------------------------- ------------------------------ Date: 11 May 91 20:23:27 GMT From: wuarchive!rex!rouge!dlbres10@decwrl.dec.com (Fraering Philip) Subject: Re: Launch Costs XXIV -- Wright Bros. Flyer to carry tanks to Kuwait! They say that the best way to get people to believe a falsehood is to tell it over and over and over and over and over and over and over again. In article <2797@ke4zv.UUCP> gary@ke4zv.UUCP (Gary Coffman) writes: >I think NASA shouldn't be in the launcher business. Rather NASA should >be pushing the edges of the envelope and making their results available >in the public domain, both their successes and their failures. However, >I believe that one of those edges of the envelope happens to be cost >per pound to orbit and that another edge of the envelope is heavy lift >to orbit. Therefore NASA should vigorously persue a technical demonstration >program resulting in an ALS system designed to push both cost per pound and >heavy lift to the limits of 1990s technology. Resurrecting early 60's launcher >technology can be left as an exercise to private companies, if they can find >a market for such expensive heavy lift capability. An ALS demonstration >program can form the base for a real privately built heavy lift transportation >system that will benefit from thirty years of technological progress. >Unlike Nick, I believe that chemical rockets aren't some obsolete technology >that needs to be left behind. Rather, what needs to be left behind are >obsolete 1940s, 1950s, and 1960s designs for chemical rockets. [more left out about that 'cheap heavy booster' that's going to save the world and even make coffee automatically for everyone, although only as good as yankee coffee :-( :-)] But what if it is easier to develop a just as cheap (per pound) light launch vehicle than to develop the heavy one? 1. Due to insurance factors, as well as the fact that a 'small' space business would not have to find 20 or so payloads similar in size in order to fill out the 'bus' of the booster, the small boosters will probably predominate. As an example of this, I would like to point out that the S.U. just spent a whole lot of money developing an HLV they never use. Although cost per pound figures are sketchy and I don't know them, I do know that the S.U. does launch a lot more kg into space with its smaller boosters: the 'Semyorka (sp?)', the Proton, and the Zenit (which is also their HLV's strap-on). Their HLV is being put out of business by its own strap-on used as a stand-alone booster. I would also like to point out that even with Pegasus' higher cost per pound, it is doing a booming business which noone would have predicted given the market for Deltas and Atlases. Finally, even with HLV's, the amount of stuff you can launch from Earth will be limited. The future lies with construction of space industries from extraterrestrial resources. The amount of materials involved will be orders of magnitudes larger than anything anyone could hope to launch from Earth without a Launch Loop ("Do you own a bandsaw? :-) ") And although everyone says that this will be easier with an HLV, noone has yet proven that assertion. Meanwhile, back at the ranch, a flyer from SSI details how with the materials from less than one shuttle flight, an entire External Tank could be taken apart into aluminum sheet. So I don't think there will be any trouble assembling materials meant to be assembled in orbit, and a 200,000 lb booster would probably be superfluous. As Nick, who is a skeptic on cheap launch in general, said, if you want cheap launch, develop cheap launch, don't spend billions and billions in the name of developing cheap launch. I would like to add: because in that sort of enviornment, another $500 million per launch 'cheap' launch vehicle will be developed. -- Phil Fraering dlbres10@pc.usl.edu ''It's a Flash Gordon/E.E. Smith war, with superior Tnuctip technology battling tools and weapons worked up on the spot by a billion Dr. Zarkovs.`` - Larry Niven, describing the end to _Down in Flames_. ------------------------------ Date: 11 May 91 08:03:38 GMT From: SUWATSON.STANFORD.EDU!REM@ucbvax.Berkeley.EDU Subject: Regarding terraforming (This is my very first posting directly to a usenet newsgroup.) I think it's silly to think the only places anybody would want to live and work is on a planet or in a space station that has an Earthlike atmosphere. Presently there are places on Earth where people live that are rather inhospitable for a nude human. Maybe inside the home one can undress and lie around in comfort, but outside clothes are mandatory for survival. Clothes prevent excessive loss of body heat, prevent excessive exposure to ultraviolet light, and shoes prevent penetration of the foot by sharp objects. Clothes even protect against scraping from bushes and grass when hiking. Someday when we all live in space, "spacesuits" might be considered "clothing", something you always have on except when you're lounging around at home. Besides protecting against vacuum of space and X-rays etc. from the Sun, spacesuits will prevent transmission of respitory viruses, and may perhaps be legally required in all common areas where people from various distant places meet, to avoid causing epidemics. So maybe it would be a good idea NOT to terraform a planet, so that people building habitats there won't be affected by airborn viruses and possibly get sick millions of miles from the nearest medical-treatment centers? And maybe NOT to equip a space station with air in common areas either? P.s. On the actual topic of terraforming Venus. I think we should simply suck out from the upper Venusian atmosphere whatever sulfur and other elements we need in space industry, and over the thousands of years the atmosphere will gradually thin out. Then someday we can reconsider this question. (Sucking is done by ionizing the stuff then using a charged plate to attract it, then centrifugal force or something like that to throw the now electrically-neutral stuff from the charged plate into some collector. Maybe centrifugal force can be nearly the entire mechanism for collecting and (1) if still a gas, compressing it enough for a mechanical pump to take over, or (2) if now a solid, packing it directly into a bucket? Or maybe electrical attraction can be the entire mechanism for pushing the stuff into crevices in some porous storage device?) ------------------------------ Date: 9 May 91 16:49:03 GMT From: dog.ee.lbl.gov!hellgate.utah.edu!caen!sdd.hp.com!usc!rpi!crdgw1!gecrdvm1!gipp@ucbvax.Berkeley.EDU Subject: Re: Saturn V and the ALS In article <1991May8.232039.532@iti.org>, aws@iti.org (Allen W. Sherzer) says: > > >Well you got to remember an important factor here. NASA intends to spend >over ten billion dollars to build this thing. They need a LOT of trust to From what I understand, nobody is spending 10 billion bucks on this system. I thought the whole thing got demoted to spending a few hundred million on engine research and feasibility studies. My impression is that ALS is a good moniker to sell the people on "yeah we really are advancing launcher wise" without actually starting any new launcher program. Besides, how do you wheedle money out of the space budget unless you can say, " we might actually use the technology we're investigating/inventing"? > >First explain to me why it costs $10 billion and ten years to do what >McDonnell and Martin say can be done for $500 million and four years. quite simple: we need to spend this kind of money to pork barrel votes and keep the aerospace business in spare change, exactly like we've done for the military for the past 40 years. Now, tell me why you think McDonnell and Martin can do it on the cheap, other than your stock answer of "they told me so". If they think they have such a great gold mine, why don't they start digging with their own money? Answer quite simple: they think they can get more from a pork barrel congress? >What's wrong with their approach? > >>This isn't a flame. It is a serious question. How can NASA shake the bad >>rep it got over Shuttle? > >First, admit they have a problem. Their request for new orbiters every year Yeah right! that would go over as big as Bush admitting that he actually knew every single detail on the Iran-Contra scandal, or as big as an opponent admitting he's afraid of getting in the ring with Mike Tyson. >imply to me that they think things are just fine. Then I would like to see >more emphasis on commercial procurement of ordinary launch services. > >>But don't condemn NASA forever or we'll never get anything built. > >Why is NASA the only agency who can build things? they're the only ones willing to spend money to start a program? Pete > > > Allen >-- >+---------------------------------------------------------------------------+ >|Allen W. Sherzer | Allen's tactics are too tricky to deal with | >| aws@iti.org | -- Harel Barzilai | >+---------------------------------------------------------------------------+ ------------------------------ Date: 10 May 91 04:02:37 GMT From: usc!rpi!news-server.csri.toronto.edu!utzoo!henry@ucsd.edu (Henry Spencer) Subject: near-station maneuvering In article <91129.131516GIPP@GECRDVM1.BITNET> GIPP@gecrdvm1.crd.ge.com writes: >... If I recall correctly, concern was greater now that Freedom >has shrunk ... due to the lack of manuevering space and the need >to be that much more precise so as not to hit the closer modules. >Henry will probably write about it in a couple of months when he does >his summary of the issue :-). You're behind the times; the summary for that issue has already appeared. :-) -- And the bean-counter replied, | Henry Spencer @ U of Toronto Zoology "beans are more important". | henry@zoo.toronto.edu utzoo!henry ------------------------------ Date: 11 May 91 22:38:46 GMT From: rochester!dietz@rutgers.edu (Paul Dietz) Subject: Re: Launch Costs In article dlbres10@pc.usl.edu (Fraering Philip) writes: >I would also like to point out that even with Pegasus' higher cost >per pound, it is doing a booming business which noone would >have predicted given the market for Deltas and Atlases. Also, consider that it the cost/lb of the Pegasus can probably be reduced considerably. Two more or less straightfoward improvements are: higher Isp liquid fuel upper stage(s) and the addition of ramjets to the first stage (as was done with the X-15 at one point, admittedly with near-disasterous results). Paul F. Dietz dietz@cs.rochester.edu ------------------------------ Date: 11 May 91 01:39:34 GMT From: swrinde!sdd.hp.com!caen!sol.ctr.columbia.edu!emory!wa4mei!ke4zv!gary@ucsd.edu (Gary Coffman) Subject: Re: Hypersonic Transport In article lc2b+@andrew.cmu.edu (Lawrence Curcio) writes: >I'm a grad student at a policy school, and I don't read this group regularly >so forgive me if this is old stuff. Anyway, occasionally we get a guest >lecturer who mentions hypersonic transport. We are told that the supersonic >phase is to be skipped altogether, and the next stage of travel is >via space. No two points on the globe more than a couple of hours away, >and all that. The last person, a prof from UNC, asserted that this was to >be a spinoff of shuttle technology. > >Now I don't want to be a wet blanket or anything, but it seems to me that >the shuttle is an example of a technology that has grown well past its >practical scale. So what's the scoop, folks? Is this stuff on the horizon >or have I been treated to Science Fiction Theater? My opinion, Science Fiction Theater. The real problem with most air transport is the delay going and coming from the airport rather than the flight time alone. Limited routes such as US-Australia, Europe-Japan, etc could benefit from hypersonic transport, however, the traffic volume is unlikely to be available that is willing to pay the costs necessary to make it practical. What has to be analysed is the incremental cost for a given percentage decrease in total trip time. Currently, flight time, not counting delays for take offs and landings, must exceed two and half hours to be 50% of total average trip time. On a typical trans-Atlantic flight, total trip time averages eight and a half hours with no more than six hours spent in the air. Reducing air time to two hours gives a total trip time of four and a half hours. If the fare only doubled, cost per hour for the traveller would remain the same and looks like a good deal. However, total travel cost remains doubled and may cause the traveller to rethink making the trip at all. And, holding flight costs to only twice that of subsonic flight appears totally unrealistic. Arguments that a traveller's time is valuable enough to justify the increased costs often neglect the fact that, for example, the 12 hour time differental between Australia and the US would cause the travel day to be shot anyway, even if the trip time were nil. Leaving at 9am and arriving at 9pm, zero trip time, means the business day is over anyhow and a layover of 12 hours at the destination before business can be conducted. One might as well sleep on the plane and save money. On shorter routes, flight time is often only a small percentage of total trip time. On a typical route that I often travel the time to travel to the airport, check in and loading, wait on ramp for takeoff clearance, flight time, time spent stacked in the pattern waiting to land, unloading and baggage claim, and travel time from the airport are within a few minutes of the time needed to *drive* directly to the destination. And in the latter case rental cars aren't necessary at the destination and tools, luggage, etc aren't at risk of theft or destruction. Cost per mile is similar and freedom of action is maintained. This is obviously not an option on transoceanic trips where hypersonic travel is postulated. Still it points up the fact that reliance on air travel in general is often not even the best *current* alternative. Gary ------------------------------ End of SPACE Digest V13 #542 *******************