Date: Sat, 26 Sep 92 05:00:04 From: Space Digest maintainer Reply-To: Space-request@isu.isunet.edu Subject: Space Digest V15 #248 To: Space Digest Readers Precedence: bulk Space Digest Sat, 26 Sep 92 Volume 15 : Issue 248 Today's Topics: a twist on dynamic structures (2 msgs) Clinto and Space Funding (3 msgs) Clinton and Space Funding (2 msgs) Clintonomics and Space (non) Funding Galileo Update - 09/24/92 Help ! Mariner Mark II vs smaller missions New Information Service (update) New Planet? (3 msgs) PUTTING VENUS IN AN ORBIT SIMILAR TO THE ORBIT OF THE EA QUERY: Apollo/Landing Module operations UTMB (University of Texas M Waverider 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: 25 Sep 92 14:28:41 GMT From: stiles@quik.clearpoint.com Subject: a twist on dynamic structures Newsgroups: sci.space Since the recent postings about Lofstrom Loops and such, I have been thinking about various twists on the idea, and came up with one last night... How about fuel pellets being accelerated from a ground-based station up into the 'nozzle' of a rocket ship in flight. I imagine that the acceleration of such pellets would have to be electromagnetic, and so some amount of iron might want to be embedded in the pellets. Based on the descriptions of the Lofstrom Loop, I assume that a stream of such pellets could comprise a 'stable' dynamic structure, and being consumable would eliminate the start up/shut down problem. I can certainly see some big problems with this, like how to effectively direct this stream up into the nozzle of an operating rocket engine, although up into the center of a cluster of engines might work. However, if the fuel is not placed directly into the operating nozzle, how do you get it there? These seem to be the biggest problems I have been able to imagine. Am I missing something obvious? ------------------------------ Date: 25 Sep 92 15:37:21 GMT From: Henry Spencer Subject: a twist on dynamic structures Newsgroups: sci.space In article stiles@quik.clearpoint.com writes: >How about fuel pellets being accelerated from a ground-based station >up into the 'nozzle' of a rocket ship in flight... The idea has been proposed before, in the context of interstellar propulsion (where energy storage is a severe problem and it's helpful to have home base supplying the power). I think you'd have trouble making it work from the ground because of problems like air friction. -- There is nothing wrong with making | Henry Spencer @ U of Toronto Zoology mistakes, but... make *new* ones. -D.Sim| henry@zoo.toronto.edu utzoo!henry ------------------------------ Date: Fri, 25 Sep 92 12:17:14 BST From: amon@elegabalus.cs.qub.ac.uk Subject: Clinto and Space Funding > >Do you really think that it is a coincidence that > >the military and space budget cuts coincide with the Japenese gaining a > >technological edge? > > Come on... They've had an edge for a *lot* longer than that! > Does not compute... The USA thoroughly trounced both of them in 1945; Japan did not become technologically competitive (transistor radios not withstanding) until the mid to late 1970's. The DOD budget has been pushing technology since WWII (and more so after Keenan's famous then-anonymous article calling for a policy of containment published in Foreign Affairs in 1947(?) ); and US space program spending started its' up turn in fiscal 1958, I believe. Not that I don't agree with much of your statements. Just that this one was incorrect. ------------------------------ Date: Fri, 25 Sep 92 12:32:48 BST From: amon@elegabalus.cs.qub.ac.uk Subject: Clinto and Space Funding > This is where that military money can and should be spent. However, the typical > Reagan/bushist freemarketeers are completely against this government > intervention in the marketplace, and, it seems from here, bury any attempt at a > US Industrial policy. The frequent cries that 'goivernment intervention doesn't > work' are plainly wrong. Look at Japan. Look at the EEC even, where > technological programmes seem to be coming together. > Ah... I should have finished reading before I said I agreed. Japan has done nicely because their companies have concentrated on consumer items, and their economy has based itself on consumer items. The US enforced constitutions both their and in Germany kept their defense spending down so they both focused on civilian matters. The US, on the other hand, took on the "american man's burden" of world defense, and its' economy came to be greatly affected by defense related matters. That warping of the market there is now being undone, but not without a great deal of pain in the transition. The Japanese acted as businessmen. In the 50's they built junk, knick-knacks and such. Japanese made was synonmous with "cheap". In the late 50's they discovered transistor radios. Still synonomous with cheap. A tiny tinny sound, but every teen had one. In the 60's they built their companies on the toehold in electronics, and got into building cheap but reliable small cars, as did the Germans with the Volkswagen. In the 70's they careful business approach began to pay off, as the companies kept plowing profits back into R&D. And in particular they adopted Deming and TQA at a very early level. They were still largely copying technology, but going into the 80's they picked up on the Video Tape Recorder and made it a household item. No magic government intervention involved there. Just a lot of market savvy and good quality at low prices. Now as we go into the 90's, they are beginning to build off the base of borrowed technology to become a net generator of new technology. They may well succeed. People who have idolized (or demonized as the case may be) MITI, really don't understand what a minimal impact it has had. And as for the Japanese government, it doesn't run an industrial policy. It runs by which corporation or organized crime cartel has most recently given it the most illegal loot. And whatever did happen to the terrible threat of the 5th Generation Computer initiative? Or the US counter initiative that seems to have quietly died because they couldn't keep up with Seymour Cray, a single genius in a private company? ------------------------------ Date: Fri, 25 Sep 1992 15:22:02 GMT From: Doug Page Subject: Clinto and Space Funding Newsgroups: sci.space In article <1992Sep24.171759.9027@vax.oxford.ac.uk>, clements@vax.oxford.ac.uk writes: |> Someone said: |> |> >Contrary to popular belief, the majority of R and D money for the armed |> >forced goes into communications, advanced IC technologies, computer |> >technology, and various other non-lethal activities. Sure some money does |> >go into weapons research, but they are they ARMED FORCES aren't they. |> |> The problem then is that the military fight tooth and nail to keep these |> developments *out* of the public arena until they have something better. Look |> at the mess with encrypting GPS etc. etc. |> |> >Now |> >don't get me wrong, I have no problem with reducing defense R and D spending |> >as long as the money goes into other R and D activities and people don't |> >lose their jobs. Like it or not, the two main technology drivers for the |> >last 5 decades |> |> (In the USA perhaps) |> |> >have been first the military and then the space program. |> |> Japan and Germany have relatively little military spending, and as a result of |> this they can spend more on government support of civilian R & D programs. |> |> >Do you really think that it is a coincidence that |> >the military and space budget cuts coincide with the Japenese gaining a |> >technological edge? |> |> Come on... They've had an edge for a *lot* longer than that! |> |> >Please don't spout off about cutting defense spending |> >until there are valid places for the money to go. This idea of cutting |> >first and then trying to figure out what to do with the money later does |> >nothing for the country except increase unemployment and sacrifice our |> >technological edge. Let's be careful how we define "technology". Did the Japanese invent TV, the automobile, VCRs, transistors, ICs, radio, computers, microprocessors, microcomputers, microwave ovens, telephones, or even the quality programs that they implement? No, they did not! Do they have a technological edge in producing the products listed? Yes, they do! The Japanese understand what the customer wants and then make it for them. Are they inovative? Yes, but primarily in the areas of manufacturing and quality. I work for a company that receives royalties from Japanese companies for technologies that are often referred to as "Japanese" technologies. Why, TI even invented (and holds the US patent for) the so-called "Japanese" transistor radio. Not to mention that it is an American TIer who was awarded the Japanese patent for the integrated circuit. The problem in the US is that if a company gambles on a new technology and loses, it can put a major dent in that company's financial condition (if not break it). As Dave Clements has pointed out above, Japan and Germany support civilian R&D programs. However, contrary to his claim, the so-called "Japanese edge in technology" has happened SINCE NASA reached the moon and the cuts in NASA's budget since then. And this Japanese "technological edge" has been achieved using primarily US inventions. (I must point out at this point that I DO remember the "inexpensive" (cheap is a more acurate word) cars that Honda was trying to get the US to buy in the early 70s prior to the Arab oil embargo. These cars were neither technologically advanced, nor were they very durable (if an owner got 50,000km service out of one they very felt lucky). The advantage that Japan has is that the government underwrites gambles on technology and, thus, encourages long term thinking. In the US stockholders can sue the board of directors of a company for not addressing short term profits. Until this either changes or the US government returns to the old way of underwriting the business risks of R&D (the development side is where we are currently falling short) through a technology focus again, be it space or military. (BTW, I personally favor space over military although each is important.) A manned space program in particular has direct benefits to "consumer technologies" since consumer products are used by humans. [stuff deleted] FWIW, Doug Page *** The opinions are mine and do not necessarily represent those of my *** *** employer. *** ------------------------------ Date: 25 Sep 92 15:00:53 GMT From: "C. Taylor Sutherland III" Subject: Clinton and Space Funding Newsgroups: sci.space,sci.astro,talk.politics.space,alt.politics.bush,alt.politics.clinton bowen@cs.Buffalo.EDU (Devon E Bowen) writes: >In article <1992Sep13.230730.18484@iti.org>, aws@iti.org (Allen W. Sherzer) writes: >> Sure he will tell you he supports space but his record indicates >> that he simply doesn't care. for myself, I didn't vote for bush >> in 88 but I will in 92. >Now I'm no Henry Spencer but I'm a pretty big space nut. However, if >your vote for Bush/Quayle over Clinton/Gore is because of the way they >will treat the space program, I'd say you've got your priorities a wee >bit out of whack. I, personally, vote for what I think is best for the >society in general and not just my individual interests. >[Yeah, I know this is old news but I'm still catching up in this group] >Devon Think of it this way. If everybody votes for their personal interests and many people end up having the same interests, it is called the interest of society. -- We're not hitchhiking anymore. We're riding! -the immor(t)al Ren & Stimpy The Fly Boy <| E-MAIL: taylors@hubcap.clemson.edu |> +--<| My life is a math question with one equation and 42 unknowns. |>--+ ------------------------------ Date: 25 Sep 92 13:58:49 GMT From: Gary Coffman Subject: Clinton and Space Funding Newsgroups: sci.space,sci.astro,talk.politics.space,alt.politics.bush,alt.politics.clinton In article <1992Sep23.214254.3010@digibd.com> rhealey@dellr4.digibd.com (Rob Healey) writes: > What I want to know is why everybody WANTS government involved > with ANY of the space exploration? Government is what generally > messes up perfectly good ideas. Doesn't matter whether it's > a Republican or a Democrat in office, space utilization suffers > because its at the spending whim of a government. B^(. > > Government is OK at doing initial exploration, i.e. Christipher > Columbus, but things don't get rolling till private enterprise get's > involved, i.e. the colonies were usually paid for by investors who > expected the colonies to pay for themselves. > > What we REALLY need to do is convince investors that starting > a colony on the moon in our time is as good of an idea as > starting a colony in the new world was back in the 17th > century. Let's see, ole Chris landed in the New World in 1492, the first viable colony landed in 1620. Apollo landed on the Moon in 1969. So we should expect private enterprise to land a commercial colony on the Moon about 2097. Let's call it New Plymouth. In the meantime, I guess we'll have to let the great navigators be funded by the government. The maps have to be filled in in those spaces that now say "Here there be dragons." Gary ------------------------------ Date: 25 Sep 92 16:25:53 GMT From: Herman Rubin Subject: Clintonomics and Space (non) Funding Newsgroups: sci.space In article <1992Sep24.164735.9025@vax.oxford.ac.uk> clements@vax.oxford.ac.uk writes: >In article , 18084TM@msu.edu (Tom) writes: >> If this goof gets elected after all but promising to raise taxes $1.5E11 >> BEFORE the election, think of the things he'll do once he's in. Brrr... >And what is Bush going to do if he gets back in now he's sold his soul to the >Fundamentalists like Pat Robertson???? A literal reading of the Bible can be used to not only justify but demand movement toward manned settlement in space. Many religious leaders can be sold on this. (Read the first commandment in Genesis, and replace "earth" by "the physical universe.") -- Herman Rubin, Dept. of Statistics, Purdue Univ., West Lafayette IN47907-1399 Phone: (317)494-6054 hrubin@pop.stat.purdue.edu (Internet, bitnet) {purdue,pur-ee}!pop.stat!hrubin(UUCP) ------------------------------ Date: 25 Sep 92 15:10:09 GMT From: Chris Kostanick 806 1044 Subject: Galileo Update - 09/24/92 Newsgroups: sci.space,sci.astro,alt.sci.planetary Ron, could you give a brief explanation of the power bus imbalance model? Thanks! Chris Kostanick ------------------------------ Date: Fri, 25 Sep 1992 22:18:25 GMT From: Ron Baalke Subject: Help ! Newsgroups: sci.space In article , PHARABOD@FRCPN11.IN2P3.FR writes... >There is a terrifying article in the last issue of the French >"Sciences et Avenir" - a really serious popularization review. >They say that, on September 28, 2000, the Toutatis asteroid >(diameter 1 kilometer) may hit the earth. They say that >normally the distance would be the same as the Earth-Moon >distance, but that there is a rather big uncertainty. They >assure that their info comes from Nasa experts. This is the >main article in this issue. > The comet will pass .074 AU from Earth in the year 2000, which is 3 times farther than its closest approach coming up on December 8 (.025 AU). ___ _____ ___ /_ /| /____/ \ /_ /| Ron Baalke | baalke@kelvin.jpl.nasa.gov | | | | __ \ /| | | | Jet Propulsion Lab | ___| | | | |__) |/ | | |__ M/S 525-3684 Telos | Quiet people aren't the /___| | | | ___/ | |/__ /| Pasadena, CA 91109 | only ones who don't say |_____|/ |_|/ |_____|/ | much. ------------------------------ Date: 25 Sep 92 09:10:31 GMT From: Anita Cochran Subject: Mariner Mark II vs smaller missions Newsgroups: sci.space There have been several articles lately discussing the demise of Mariner Mark II class missions (almost gleefully in some cases) and touting the "smaller, cheaper, faster" missions being discussed. I will probably regret getting involved but I thought it worth pointing out that the goals of these two types of missions are not the same. Yes, you can fly a smaller spacecraft past Pluto and answer some of the important questions. By its very nature, fast flybys are limited in what they accomplish and they are good for the first reconnaisance of a body. However, we have done this step for the gas giants and just repeating that would not really accomplish any new science. So one has to ask what is the next logical mission to a body such as Saturn? Well, one could go back and study just the satellites or the rings or the atmosphere but the most important science comes from a study of the system as a whole -- the details of the bodies and the interactions of the different parts. Also, once you are in the system, it pays to do a complete tour. This conclusion on the most important science was elaborated in a document a number of years ago by the National Research Council's Committee on Planetary and Lunar Exploration. I should note that this is not a NASA committee. Well, if we agree that we want to study the system as a whole, this puts certain requirements on the instrument complement. It suggests one needs an imaging instrument, IR and UV spectrometers, and fields and particle experiments. A probe for Titan's atmosphere is a nice thing to have too, once you have a spacecraft going that way. So, add these together and what do you have? You have a Mariner Mark II class mission. And once the spacecraft is going, you might as well send a full spacecraft. Well, can you do this mission with a discovery class mission or even a $400M mission? No, not if you want the systematics. One can build a smaller faster cheaper spacecraft if one wants to study a single aspect. But you just cannot do the systematics. So does this make smaller cheaper faster an invalid concept? Of course not. There are many missions which are well suited to discovery class (no more than $150M to launch+30 days and no more than 3 years development) or moderate (~$400M) missions. A perfect example is the NEAR (Near Earth Asteroid Rendezvous) mission. This is projected as discovery class mission number 2. It is under the direction of APL/JHU and they feel they can pull if off. It will, however, only carry 3 instruments (this was said in a talk I heard this week by one of the APL Project scientists). Now, are we better off with many discovery class missions or one Cassini? Well, that is a matter of opinion. Both can do first rank science and only Cassini can do the systematics. I think it would be a tragedy if we only did discovery class missions. But the day of frequent flagship missions such as Cassini is over. And that is really sad. I know there are those of you out on the net who think it is because of mismanagement or scientist greed and there are some elements of that. But big missions are expensive. There is no real way around that. And the most efficient mission which accomplishes what Cassini will accomplish is still going to cost $1B. Disclaimer: I am in no way connected with the Cassini mission. -- Anita Cochran uucp: !utastro!anita arpa: anita@astro.as.utexas.edu snail: Astronomy Dept., The Univ. of Texas, Austin, TX, 78712 at&t: (512) 471-1471 ------------------------------ Date: 25 Sep 92 09:51:34 GMT From: Spacelink Subject: New Information Service (update) Newsgroups: sci.astro,sci.space.shuttle,sci.space Our organization "Spacelink" was unaware that there is another organisation called Spacelink when we formed. It is difficult to actually change our name at this time but to make it easy to reconize us we are changing our email address to space_nz@kiwi.gen.nz Thank you for your mail informing us of Spacelink in America. Spacelink is a Space Information Bureau based in New Zealand. Our aim is to supply answers to people's questions whether they be simple or complex on the history of human accomplishments in space. You can contact us through our Email address of space_nz@kiwi.gen.nz, or by writing to Spacelink at PO Box 331402, Takapuna, Auckland 9, New Zealand, (Please enclose an SASE), or by Fax on 64-9-8494282. This is a free service for the curious, supplied by a team of voluntary Spaceflight enthusiasts. This Article is to put our Previous Posted Article right with regards to our email address. -- DOMAIN: space_nz@kiwi.gen.nz SNAIL: PO Box 331402, Takapuna, Auckland 9, New Zealand FAX: 64-9-849-4282 ------------------------------ Date: 25 Sep 92 08:30:19 GMT From: Anita Cochran Subject: New Planet? Newsgroups: sci.astro,sci.space In article <1992Sep24.182647.24391@ulrik.uio.no>, jarleb@athena.uio.no (Jarle Brinchmann) writes: > Now, this thing has been on the net ever since last weekend, is > there anybody out there who know anything about new observations > taken place ? It is my understanding that Dave Jewitt and Jane Luu are on the telescope this weekend and will follow up. I also have an observing run this weekend. Mine is at McDonald Observatory. I have already gotten a pair of positional images tonight. However, with the slow motion of this object there is no "streak" on the image to confirm one has observed it so no one will know until their data are reduced. I will also try to observe it the next 3 nights (weather permitting). Of course, you must understand that the "orbit" which has been derived for this object so far is very uncertain. Thus, it could be in a substantially different position than predicted. If that is the case, I have a nice image of a field without an object and have not observed the object. Until we have a refined orbit, reliably observing it will not be possible. As for whether it is a "planet", it is a minor planet at best. The current size estimate is based on a guess (from the orbit) of where it is relative to the sun and a guess about how much light it reflects (its albedo). The largest size comes about if it is dark. The discovers assumed 5% albedo. If it is as bright as say Pluto, then it is a tiny object. -- Anita Cochran uucp: !utastro!anita arpa: anita@astro.as.utexas.edu snail: Astronomy Dept., The Univ. of Texas, Austin, TX, 78712 at&t: (512) 471-1471 ------------------------------ Date: Fri, 25 Sep 1992 12:17:59 GMT From: David Tonhofer Subject: New Planet? Newsgroups: sci.astro,sci.space In article <92259.152146LABBEY@GTRI01.GATECH.EDU> LABBEY@GTRI01.GATECH.EDU writes: >The following bulletin was posted last night on CompuServe's ASTROFORUM: > >Sb: #Object beyond Pluto >Fm: SKY TELESCOPE 70007,2762 >To: All > > There is some REALLY BIG NEWS just now breaking in the astronomical world. > The IAU Central Bureau for Astronomical Telegrams has just issued IAU > Circular 5611 to report the discovery of a faint object that seems to be > outside the orbit of Pluto! > [...stuff deleted...] > Dan Green [...] says it could turn out to be a huge comet coming in. ^^^^^^^^^^^^^^^^ > It is now so far away that if it is a comet on a very elongated orbit it may > take 30 years to reach perihelion. Then it could well become the Comet of > the (21st) Century!! Ah! Looks like 'Lucifer's Hammer' to me... 8-) Dammit! --David ------------------------------ Date: 25 Sep 92 18:05:49 GMT From: Matthew Sheppard Subject: New Planet? Newsgroups: sci.astro,sci.space jarleb@athena.uio.no (Jarle Brinchmann) writes: >> Dan Green of the CBAT says they really don't want people to start >calling this >> thing "Planet X" or the 10th planet or anything like that. It's >> just too soon >>to say. For example, he says it could turn out to be a huge comet >coming in. >>It is now so far away that if it is a comet on a very elongated orbit >it may >>take 30 years to reach perihelion. Then it could well become the >Comet of the >>(21st) Century!!-- > >Well, I hardly would call it planet nr 10 anyway. Nobody expect it >to be much larger than 250 km in diameter, and then it is a rather >big piece of rock og on hell of a comet, but hardly a planet. >Now, this thing has been on the net ever since last weekend, is >there anybody out there who know anything about new observations >taken place ? >I heard there were plans to do some observing this weekend is this >true ? >Anyway, while we can, let's hope it is a comet !! Time had a good two page article on the whole thing this month. -- | Matthew Sheppard CLARKSON UNIVERSITY sheppamj@sun.soe.clarkson.edu | | I'd rather have a bottle in front of me than a frontal lobotomy.ANoN | | I don't want a pickle. DoD#477 TEP#477 RIDE FREE (8^]..etcetera.. | ------------------------------ Date: 25 Sep 92 16:47:38 GMT From: Alan Barclay Subject: PUTTING VENUS IN AN ORBIT SIMILAR TO THE ORBIT OF THE EA Newsgroups: sci.space In a previous message you said that mars' gravity was too light to hang on the lighter gasses, thus the atmosphere is thin. Titan, a moon of Saturn is slightly smaller than mars and has an atmospheric density twice earths at the surface. How do you explain that? :) Alan ------------------------------ Date: Fri, 25 Sep 1992 07:11:56 GMT From: Mike Smithwick Subject: QUERY: Apollo/Landing Module operations Newsgroups: sci.space In article <1992Sep21.053111.1@fnalc.fnal.gov> higgins@fnalc.fnal.gov (Bill Higgins-- Beam Jockey) writes: >In article <1992Sep21.015833.13643@rp.CSIRO.AU>, jdeane@rp.CSIRO.AU (John Deane) writes: >> I _REALLY_ enjoyed "The Space Shuttle Operator's Manual" >> by Joels & Kennedy >> (Macmillan 1983, Ballantine 1982). Ever since then I've wanted >> something slightly >> similar for Apollo and the LM. Does anyone know if such a thing >> was ever published? > >Such a thing was never published. (Though you have a neat idea, John.) > >I will leave it to Henry Spencer to tell you: > >1) Of the available literature, what comes closest, and >2) What to read if you want to WRITE *The Apollo Operator's Manual*. > > >Bill Higgins | "[Theatregoers], if they did not The closest thing is the REAL thing, called "The Apollo Operations Handbook". They came in two volumes for each spacecraft, the CM and LM. Vol. 1 is spacecraft systems and vol. 2 covers the general operational of the vehicles. These are not light reading, the CM manual, vol 1 alone is about 1000 pages, with the LM manual about 845 pages. BTW, the Skylab manuals are much the same. The Gemini manual comes in only a single volume, and is a mere 670 pages and the Mercury manual is a slender 451 pages. For entertainment purposes only the OFFICIAL "Shuttle FLight Operations Manual" is around 20,000 pages at last count. mike P.S. Anyone have a Lunar Rover manual? I have a piece of one and want to complete it. -- "There is no problem too big that can't be solved with high explosives"-Rush Mike Smithwick - ames!zorch!mike ------------------------------ Date: 25 Sep 92 15:49:04 U From: "Patrick French" Subject: UTMB (University of Texas M EXECUTIVE OFFICE Date: 9/25/92 UTMB (University of Texas Medical_ Time: 3:51 PM Just passing on some info to anyone interested ... "UTMB (University of Texas Medical Branch) will be launching a 2 year Space Medicine Fellowship beginning July, 1993. We are about to recruit physicians for the two openings available next year and in future years ... Applicants for the Fellowship must be board-eligible or board certified physicians in a medical, surgical or psychiatric specialty. Salary is at a PG-IV level. Fellows would actively participate in a program geared to train future space biomedical researchers, and will have the opportunity to participate in the Johnson Space Center's medical operations activities throughout the two years. Fellows will also receive training from the U.S. Air Force School of Aerospace Medicine. This is a truly unique opportunity for young physicians interested in space medicine. If you know of any interested individuals (or are an interested individual), please ask them to contact Dr. Tom Blackwell at 409 772-2654 to receive more information." Please contact the above if you are interested or me if you have any problems getting ahold of Dr. Blackwell. Patrick _________________________________ Patrick M. French Phone: 617 354-1987 Special Assistant for Strategic Planning Fax: 617 354-7666 International Space University e-mail: french@isu.isunet.edu 955 Massachusetts Avenue, 7th fl. Cambridge, MA 01239 USA ------------------------------ Date: Fri, 25 Sep 92 12:43:38 GMT From: "Charles A. Lind" Subject: Waverider Newsgroups: sci.space In article , amon@elegabalus.cs.qub.ac.uk writes: >I attended an interesting lecture last night by Duncan Lunan (Bill: >do you remember the guy in the kilt selling Halley's Whiskey at the >PghL5 bid party at DC85?) of ASTRA, a Scottish space group. It was >his first visit to Belfast. > I had the opportunity of meeting these guys at the 1st International Hypersonic Waverider Symposium October 1990 This symposium was sponsored by both NASA and the University of MD and was held at the University of MD. We had THE experts and some amateurs on hypersonic waveriders from across the world. >His group, ASTRA, has been working on the Waverider idea for decades. >The idea is that a concave lower aerodynamic surface traps the >shockwave and lets the craft ride on it. They've done supersonic wind >tunnel tests, small rockets to release models, theoretical work on >meager computer resources... > I believe this work originated by Nonwieller for Caret wings. In additional many people have done work in this area. Here at MD we work on the design of optimized waveriders. Generally we optimize for high L/D. Recently we disigned an engine integrated hypersonic waverider. This was a fully optimized vehicle which utilized a 1-D scramjet model for it's engine. >He suggests the waverider as a great way for entering the martian >atmosphere and flying about dropping of probes. Unmanned though. On >Mars the touchdown speed would be 400 km/sec. He suggested he would >not wish to be the first to touch down on a non-runway at that >speed... > >He also showed ideas for a solar probe that used "aerogravity assist" >to get in close to the sun. A waverider enters an atmosphere (not TOO >deeply!) and uses it to make a driection vector change much larger >than gravity alone could do. > >This requires a rather interesting maneuver. Since it is flying at >higher than escape velocity, it enters UPSIDE DOWN and use >aerodynamics to push it towards the planet. It then has to rotate the >lift vector for escape. > I believe this information can be found in papers written by Mark J. Lewis from MD and Jim Randolph from JPL. >Sound a bit hairy to me... > >The middle of the lecture was punctuated by a non-sonic boom as the >police forensics lab, a couple km distant, got blown up. No, it >wasn't done by amateur rocket enthusiasts... Needless to say, the >after lecture pub jokes were about hypersonic forensic labs and panel >truck parts... > For more info on this concept look for papers by: John D. Anderson, Jr. Mark J. Lewis Isaiah Blankson Kevin Bowcutt Stephen Corda Thomas McLaughlin Mary Kae O'Neill These authors represent the core of the hypersonic waverider technology in the past few years. Charles Lind Department of Aerospace Engineering University of Maryland College Park, MD 20740 USA Disclaimer: These are basically my biased opinions. ------------------------------ End of Space Digest Volume 15 : Issue 248 ------------------------------