Date: Wed, 30 Sep 92 05:06:32 From: Space Digest maintainer Reply-To: Space-request@isu.isunet.edu Subject: Space Digest V15 #263 To: Space Digest Readers Precedence: bulk Space Digest Wed, 30 Sep 92 Volume 15 : Issue 263 Today's Topics: Atlas E and F questions ( Actually Pershing missile) (2 msgs) California Aerospace Clinton and Space Funding Easter Henry's hypersonic summary (was Re: Hypersonic test vehicle proposed) Mariner Mark II vs smaller missions Mars Observer orbit Military funding My final word on Ion to Pluto (long) Nick Szabo Disinformation debunking (Re: Clinton and Space Funding) nova rocket Space Digest V15 #260 Space platforms (political, not physical : -) Storage space on craft What is this ? What was the Nova booster? 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: Tue, 29 Sep 1992 20:56:48 GMT From: Henry Spencer Subject: Atlas E and F questions ( Actually Pershing missile) Newsgroups: sci.space In article <1992Sep29.165616.6348@access.digex.com> prb@access.digex.com (Pat) writes: >What i was thinking was this. Every 6 months auction a bunch of pershings... >meanwhile qualify the sounding comapnies to handle these launches, and train >them on how they are prepped... You're still basically telling them "either use our Pershings or die". This is essentially a government-organized sounding-rocket service that happens to be implemented by private contractors (who get the choice of cooperating or going bankrupt). What happened to free enterprise and innovation? Note that the successful companies, under this plan, will be the ones who run minimum bare-bones organizations solely for Pershing launches, and plan to simply go out of business the moment the Pershings run out. Companies that are trying to keep their own launch capabilities alive for the long term will have a hard time competing. >it's not socialism to have a social policy. If it walks like a duck, quacks like a duck, and craps like a duck, I call it a duck. A "social policy" whose side effect is to destroy all private competition for government-supplied launchers is socialism. -- 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: 29 Sep 92 22:43:00 GMT From: wingo%cspara.decnet@Fedex.Msfc.Nasa.Gov Subject: Atlas E and F questions ( Actually Pershing missile) Newsgroups: sci.space In article , henry@zoo.toronto.edu (Henry Spencer) writes... >In article <1992Sep29.165616.6348@access.digex.com> prb@access.digex.com (Pat) writes: >>What i was thinking was this. Every 6 months auction a bunch of pershings... >>meanwhile qualify the sounding comapnies to handle these launches, and train >>them on how they are prepped... > >You're still basically telling them "either use our Pershings or die". >This is essentially a government-organized sounding-rocket service that >happens to be implemented by private contractors (who get the choice >of cooperating or going bankrupt). What happened to free enterprise >and innovation? > >Note that the successful companies, under this plan, will be the ones >who run minimum bare-bones organizations solely for Pershing launches, >and plan to simply go out of business the moment the Pershings run out. >Companies that are trying to keep their own launch capabilities alive >for the long term will have a hard time competing. > >>it's not socialism to have a social policy. > >If it walks like a duck, quacks like a duck, and craps like a duck, I >call it a duck. A "social policy" whose side effect is to destroy all >private competition for government-supplied launchers is socialism. >-- Henry, what about the Space Vector Corporation? They have been flying, selling and using the Minuteman I platform in various forms since the late 70's. Actually Deke Slayton's company (Now EER Systems) started by launching a Minuteman I second stage from Matagorda Island in 1980. Actually the first commercial launcher for space payloads was the Aries IV as proposed by Rich Rasmussen, president of Space Vector in 1978. The Aries IV could put 3000 lbs into LEO or 150 lbs to GEO. Space vector still flys the Aries and they also contract to EER and Deke Slayton for CONSORT launches by providing the guidance system. The issue is not nearly as black and white as you suggest. Also thank you for the correction on the tonnages for coal. I was going on information here in alabama from the union coal mines. The out west production has far outstripped (pun intended) their eastern rivals. Most of the coal we use here in Alabama comes from out west now. Dennis, University of Alabama in Huntsville ------------------------------ Date: 29 Sep 92 12:30:18 GMT From: David.Anderman@ofa123.fidonet.org Subject: California Aerospace Newsgroups: sci.space California's Aerospace Industry To be the Focus of Forums The California Space Development Council, a coalition of pro-space organizations in California, is sponsoring a series of forums during October to discuss the future of the aerospace industry in California, and the future direction of America's space program. On Saturday, October 3, at the Riverside Central Library, in downtown Riverside, a congressional candidate forum will be hosted by the Inland Empire Space Group at 10 am. Among the candidates invited to the forum are Congressman George Brown, the current chairman of the House Committee on Space and Technology, and Dick Rutan, the pilot of the Voyager around-the-world aircraft. The candidates will address the issues of preserving aerospace jobs in California, and the future of the nation's space program. On Thursday, October 8, at 7:30 pm at the Reuben H. Fleet Space Theater in Balboa Park, San Diego, congressional candidates will discuss aerospace issues and the space program. The event will be hosted by San Diego L5, a chapter of the National Space Society. On Saturday, October 24, at 10am, at the Sandman Inn, in Santa Barbara, a forum on the future of the California aerospace industry will feature representatives of industry and political figures. The general public is invited to attend all of these events and admission is free. For more information on these events or the California Space Development Council, please contact David Anderman, Events Coordinator for CSDC, at 714/524-1674. --- Maximus 2.00 ------------------------------ Date: 29 Sep 92 19:36:35 GMT From: Henry Spencer Subject: Clinton and Space Funding Newsgroups: sci.space In article <1992Sep28.125324@gracie.IntelliCorp.COM> treitel@gracie.IntelliCorp.COM (Richard Treitel) writes: >Private outfits often spend billions on building an office complex or >developing a new jetliner. These efforts don't even have a guaranteed >payoff ... However, they are generally not undertaken unless the odds look pretty good. Jetliner development, for example, normally doesn't start in earnest until there are "launch customers" committed to buying the new bird in quantity. (Typically not in sufficient volume to pay back the initial investment -- that comes much later -- but enough to prove that there is a good market.) -- 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: Sun, 27 Sep 1992 12:04:43 +0200 From: Edward F Eaglehouse Subject: Easter Newsgroups: comp.lang.c,comp.unix.progammer,sci.space I don't have any actual code to calculate Easter, but if I remember correctly Easter falls on the first Sunday following the first full moon after the Vernal Equinox. An astronomical programmer should be able to provide this one. Somebody in sci.space probably can give us a formula. -- ::Ed ::ASC -- Automated Solutions Corporation --- via InterNet/Usenet ---|-- via UseNet --| "I know my own mind, and efe@aldhfn.akron.oh.us | aldhfn!efe | it's around here someplace" Automated Solutions Corp. | | -- seen on a T-shirt ------------------------------ Date: Tue, 29 Sep 1992 20:46:17 GMT From: Henry Spencer Subject: Henry's hypersonic summary (was Re: Hypersonic test vehicle proposed) Newsgroups: sci.space In article <1992Sep28.175826.1@fnalc.fnal.gov> higgins@fnalc.fnal.gov (Bill Higgins-- Beam Jockey) writes: >In the "others?" category, I would name Hermes, HOTOL, Saenger, Buran, >and HOPE. I can't summarize them in this message, but maybe soon... With such bait, how can I resist? :-) Hermes is an ESA project, rapidly dying due to funding problems, to build a small manned winged reentry craft for launch on Ariane 5. The project's objectives have been progressively scaled back since its early days, when it was essentially a mini-shuttle. HOTOL is a defunct British Aerospace project to build a reusable spaceplane, powered by an innovative jet/rocket combination engine, that would be launched by rocket sled, reach orbit, and return to a runway landing. It died because the British government, following a long tradition of ignoring or actively destroying good ideas from the British aerospace industry, displayed no interest. An attempt to revive it as a pure-rocket design, using Russian engines and launched from atop the Mriya heavy cargo aircraft, looked promising but hasn't been heard from lately. Saenger is a German proposal to launch a winged rocket-powered spaceplane from the back of a large ramjet-powered Mach 6-8 aircraft. Looks fine if they can ever build that aircraft. Low-level work underway in Germany, but don't expect a commitment to development any time soon. Buran is the Soviet (now Russian) shuttle, vaguely similar to the US one but differing in some important ways, notably in that it rides up on an Energia rather than having its own main engines. One flight so far, by an unmanned prototype. Fate unclear, because it's expensive and it never has had a clear mission. (The speculation I like is that it was basically a military program, which the civil-space people once hoped to exploit and now don't know what to do with.) HOPE is a Japanese project to build a small unmanned winged reentry craft for launch on an H-2, mostly as a research and technology project. I don't believe there is yet a firm commitment to fly it. -- 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: Tue, 29 Sep 1992 21:48:36 GMT From: Mike Wexler Subject: Mariner Mark II vs smaller missions Newsgroups: sci.space fcrary@ucsu.Colorado.EDU (Frank Crary) writes: >Are they planning to use retrtrockets for the Huygens probe? If so, >_why_? The Galileo probe makes a direct entry into Jupiter and I'd >think the entry velocities for Huygens would be lower... This was probably confusion on my part. >>Could someone with a better idea of the costs involved come up with a >>quick estimate of the previous two approaches for a similar set >>of overall goals. >However, small spacecraft offer two additional advantages: They permit >more frequent missions (there are many diagvantages to 20-year desing >to use missions) and they are much less vunerable to a failure: With >A Mariner Mark II, a single major failure could ruin the entire mission >(witness Galileo's antenna), whereas such a failure on a series of >small crafts would only jeperdize one of many parts of the mission. To be fair it should be noted that the failure of Galileo's antenna only jeopardizes part of the mission (the imaging which requires high bandwidth). Also, if you didn't need a big antenna and a powerful battery on each sattelite for communications (because of the relay sattelite), you could conceiably make a sattelite much smallar and cheaper than the ones they are planning on flying by Pluto. -- Mike Wexler (mikew@kpc.com) ------------------------------ Date: Tue, 29 Sep 1992 21:23:27 GMT From: Mike Smithwick Subject: Mars Observer orbit Newsgroups: sci.space [] Does anyone have the orbital elements for the Mars Observer? I'd like to plug them into my software so I can follow it on its journey. mike -- "There is no problem too big that can't be solved with high explosives"-Rush Mike Smithwick - ames!zorch!mike ------------------------------ Date: Tue, 29 Sep 92 19:34:44 EDT From: Tom <18084TM@msu.edu> Subject: Military funding >As I stated in my previous post. Until the programs are set up to >orderly divert the money to another R and D effort, it should stay in the >military budget where at least it is going some good. This is plain silly! The only good the (extraneous) military budget does is to pay people to work. We might as well pay them to bury rocks one day, and dig them up the next. Cut the general tax burden by the amount cut, and the companies that would love to hire technically educated people will have the means to hire them. They don't right now, because the tax burden is too high. Also, once the people in the military are making wealth (rather than things like weapons, which don't get used in peacetime, and are there- for, not wealth) the general prosperity of the country will improve. This extra wealth could easily cover the R&D the military does, especially if you buy the argument that military R&D is not as valuable as, say, car R&D or VCR R&D. -Tommy Mac . " + .------------------------ + * + | Tom McWilliams; scrub , . " + | astronomy undergrad, at * +;. . ' There is | Michigan State University ' . " no Gosh! | 18084tm@ibm.cl.msu.edu ' , * | (517) 355-2178 ; + ' * '----------------------- ------------------------------ Date: 29 Sep 1992 19:49 EDT From: Greg Macrae Subject: My final word on Ion to Pluto (long) Newsgroups: sci.space In article <1992Sep24.045007.10724@news.Hawaii.Edu>, tholen@galileo.ifa.hawaii.edu (Dave Tholen) writes... > Greg MacRae (me) writes: DT>>> Lots of interesting information, but one very important, extremely crucial DT>>> item was missing: cost, including launch. From the content of your > me>> Balderdash! The information I posted was for comparison of trip times and me>> payload fraction purposes. There have been innumerable claims that ion me>> propulsion is slow. Beyond the Mars orbit, that is incorrect; the numbers me>> prove it. > >(a) You're evading the issue. (b) You're putting words into my mouth. > >(a) The issue is cost. Please tell me how much it would cost to develop >and flight-qualify an ion propulsion system appropriate for putting, for >example, 100 kg on a 7 year trajectory to Pluto. Remember, these costs Your issue is cost. Yet you continue to avoid presentation of any cost analysis. I admit that I fully understand why no one in his right mind would attempt to present a cost analysis as justification for any project. The few analyses I have worked on have taught me how to find holes big enough to drive a $10,000 toilet seat through in any 'a priori' and many 'a posteriori' cost analyses. I will not do a cost analysis for you, it is a waste of my time. >are going to be included in the mission cost. Yes, we can argue that they >shouldn't be, but that's life. I wholeheartedly agree with the proposition >that technology development be decoupled from any one specific mission, but >unfortunately you and I don't make these decisions. For costing purposes, Your ignorance is hanging our here. Huges Research Company developed and flight qualified an ion thruster system, including power processors, for use in near earth orbit. To my knowledge, there is still no user for the system. The point is not that this system is appropriate for Pluto. The point is that development money is more often decoupled from specific missions than you realize, especially when a research center like Lewis is pushing the project rather than a development center like Marshall or Johnson. >(b) I never said ion propulsion was slow. Correct, you didn't. I did not accuse you of that particular faux pas. I don't recall who or how many did, and I don't really care. The claim occurs rather frequently. Analysis has shown that it is incorrect. I posted on this subject in the hope that I can erase some misconceptions. I am more opposed to misinformation than I am to you personally :). > >Theoretically, ion is great for fast Pluto missions. I don't recall anybody >claiming that it was not appropriate. Practically speaking, however, the >technology demonstration has yet to be done, and that is a very valid >objection. More phantom claims that the technology has not been demonstrated... We have demonstrated >10,000 hr life, characterized operation on different fuels, demonstrated 88:1 throttling, built thrusters up to 50 cm in diameter, designed for zero performance variation over the thruster life, etc. Is there something that must yet be demonstrated that is generic to all (or even many) missions? This is a genuine question that we have here. We want to know if we are overlooking something big that we shouldn't overlook. me>> There are valid objections to ion propulsion. me>> I like to think that I am aware of most if not all of them. I have seen me>> none posted here so far. > >So why don't you, if you know what they are? Let the reader determine if >any of the objections are applicable to a fast Pluto mission. > me>> If you have some that I am unaware of, let's hear me>> them... > >I'm not in the mood to play >50 questions. When the Outer Planets Science Working Group had its >presentation from the ion drive folks, the cards were laid out on the table >and the group collectively assessed the situation and felt that the time was >not yet right, while at the same time thinking highly of the prospects. I am getting tired of your raising the OPSWG as a method of validating your claims. I have heard enough blathering to conlude that you either did not attend the propulsion sessions or you slept through them. The biggest detraction that ion thrusters currently face is the power supply requirements. For Pluto missions, PV arrays obviously will not suffice. That pretty much leaves nuclear sources. Furthermore, the low mass efficiency of RTG's combined with the high power requirements drive you to a nuclear reactor as the power source. The biggest issue facing ion thrusters for interplanetary missions is qualifying a nuclear reactor for flight. Even that is more of a political issue than a cost issue. Although the political aspect tends to drive the cost far higher than is technically necessary. This is the ONLY issue that I have seen that is big enough to kill ion for Pluto without any further analysis required. In all fairness to Mr. Tholen, ion seems to get a bad rap largely because it has been in development since the mid 1950's and the only real ion mission so far has been SERT-2. The thruster was radically different from modern thruster technology. The common assumption is that the technology must be immature for it not to have flown. It tends to be dismissed almost out of habit when missions are being planned, and it has never recieved the focussed monetary attention that a major mission can offer. It is probably inapropriate for a near term mission to Pluto (unless someone is willing to fly a Topaz reactor:) ). It is also very difficult to optimize a low thrust trajectory, whereas any high school graduate can solve the two body problem on a hand calculator for a reasonable impulsive mission approximation. This makes it more time consuming and expensive to compare electric propulsion in any meaningful fashion. Also, fewer people can do it. This often leads to an inadequate basis for comparison. This is my bitter response to what I see as uninformed ion bashing. I apologize if it is too close to a flame. Judgeing from the recent decline in ion posts, interest is waning. If anyone has further questions for ME, about ion, please E-mail them. Greg ----------------------------------------------------------------- MacRae | Friend, that open mouth | Reveals your whole interior spgreg@mars.lerc.nasa.gov | Silly hollow frog! | -Anon. ----------------------------------------------------------------- ------------------------------ Date: 29 Sep 92 14:03:12 From: Steinn Sigurdsson Subject: Nick Szabo Disinformation debunking (Re: Clinton and Space Funding) Newsgroups: sci.space In article <1992Sep29.170516.11468@cs.rochester.edu> dietz@cs.rochester.edu (Paul Dietz) writes: Wingo posted the following: > No we are not still mining huge amounts of coal. We are mining less > coal today than in the seventies. This is quite wrong. From the 1992 World Almanac: Year US Coal Production (million metric tons) ----------------------------------------------- 1990 1035.9 Did you know that if this coal was put into 100kg bags and dropped on people's heads there is enough there to squish the entire World's population twice over! ;-) And that's just US production!!! Stop the production of this criminally dangerous product Right Now! | 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, 30 Sep 1992 01:07:04 GMT From: Flammable Jammies Subject: nova rocket Newsgroups: sci.space If interested I will get the authors name. Also the book lists approximate measurements to this beast...let me know. FYI Thomas >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> Thomas R. Raich Microcomputing Coordinator/ I dont believe in Academic Computing Center quantum physics St.Olaf College when it comes to Internet: raich@acc.stolaf.edu matters of the heart Phone 507-646-3289 Applelink:UO691 --Crash Davis <<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<< "I have seen things that you people wouldn't believe. Attack ships on fire off the shoulder of Orion. I watched c-beams glitter in the dark near the Tannhauser Gate. All those moments will be lost in time, like tears in rain. Time to die" -- Roy, "BladeRunner" >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> ------------------------------ Date: Tue, 29 Sep 1992 05:06:52 LCL From: Space Digest maintainer Subject: Space Digest V15 #260 >TIME interviewed a group of the nation's leading economists (gee, I didn't >see Thomas' name...) and asked them to comment on various aspects of >both Bush's and Clinton's economic plan. As a sneak preview, *none* >of these professionals expressed the right-wing paranoia so beautifully >displayed by Thomas. They did have some doubts about both Clinton's and >Bush's planned policies, however there was a slight majority consensus >that Clinton's would result in better long term growth. Of course the >objective reader may choose to ignore the comments of talented professionals >and accept the statements of a single armchair quarterback (read "Thomas"). >Weirder things have happened... Lay a thousand economists end-to-end, and they won't reach a conclusion. I doubt TIME's choice of economists reflected a decent range of political opinion, so I doubt their conclusions, TIME is, after all, generally liberal. -Tommy Mac . " + .------------------------ + * + | Tom McWilliams; scrub , . " + | astronomy undergrad, at * +;. . ' There is | Michigan State University ' . " no Gosh! | 18084tm@ibm.cl.msu.edu ' , * | (517) 355-2178 ; + ' * '----------------------- ------------------------------ Date: 29 Sep 92 20:07:20 GMT From: Henry Spencer Subject: Space platforms (political, not physical : -) Newsgroups: sci.space In article <1992Sep29.173235.8579@nsisrv.gsfc.nasa.gov> xrcjd@mudpuppy.gsfc.nasa.gov (Charles J. Divine) writes: >...now read books that were banned 50 years ago. But similar books >were actually available 150 years ago. Book banning... >got its start in the latter part of the 19th century. Before then >people didn't much care what you read... Bear in mind, though, one reason for this: people didn't much care what "you" read because there was a general assumption that if "you" were reading anything, "you" were white, upper-class, and probably male... and hence trustworthy. Dangerous lower-class scum mostly couldn't afford books -- which were very expensive until about the mid-19th century (there was a *reason* why the family bible was a treasured possession passed down from generation to generation!) -- and often were nearly illiterate anyway. People started caring about what others read when "others" started including people unlike them. It's still true, too. You don't see people campaigning to ban some vile and disgusting type of pornography because it has a bad effect on *them*. It's always somebody else whose feeble, gullible mind is going to be corrupted by that awful stuff. This no longer has much to do with sci.space. Followups pointed to alt.censorship. -- 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: Tue, 29 Sep 92 19:43:00 EDT From: Tom <18084TM@msu.edu> Subject: Storage space on craft >5E5 bits is only 64k, I can't believe that. 5e8 is more plausible, but >at 64 megs might be more than they'd put in (me, I'd go for a gigabyte >:->). Maybe 5e5 bytes (512k??) 512k for holding images? Seems pretty small. -Tommy Mac . " + .------------------------ + * + | Tom McWilliams; scrub , . " + | astronomy undergrad, at * +;. . ' There is | Michigan State University ' . " no Gosh! | 18084tm@ibm.cl.msu.edu ' , * | (517) 355-2178 ; + ' * '----------------------- ------------------------------ Date: 29 Sep 92 19:38:03 GMT From: Henry Spencer Subject: What is this ? Newsgroups: sci.space In article PHARABOD@FRCPN11.IN2P3.FR writes: >Have the U.S. some kind of RPV with such performances ? If so, it is secret, so why bother asking? -- 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: 29 Sep 92 19:46:06 GMT From: Henry Spencer Subject: What was the Nova booster? Newsgroups: sci.space In article <1992Sep29.170642.14729@elroy.jpl.nasa.gov> pjs@euclid.jpl.nasa.gov writes: >... plans during the Apollo program to construct a booster even >larger than the Saturn V, called the Nova. This monster would >have had 8 F1s on the first stage and some plans called for a >nuclear engine-propelled third stage. There were a number of different Nova proposals; the name didn't refer to a single well-polished design. It was basically meant for the direct- flight approach to a lunar landing, not involving either on-orbit assembly or a separate lunar module. The idea mostly died when it became clear that it could not be ready in time for Kennedy's deadline, although it persisted in small ways for a while thereafter (for example, there was a "Saturn C-8" proposal which had eight F-1s). The final death knell was the choice of Michoud as the launcher assembly plant, since its ceilings were only barely high enough for the Saturn V first stage and could not have held anything bigger. There were nuclear-final-stage proposals for the Saturn V and various other launchers. >what was the payload to LEO? To the lunar surface? ... Never well defined, since the booster design was never finalized. Double the Saturn V's would be a reasonable guess. >... What type of nuclear engine was proposed? Early on, could have been almost anything. I've seen a drawing for an Orion third stage for a Saturn V, if memory serves. Later, it would have been a Nerva. >...How far did this thing get on the drawing board? Not very. -- 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 ------------------------------ From: Henry Spencer Newsgroups: sci.space Subject: Re: Miscellaneous responses to hypersonic questions Message-Id: Date: 29 Sep 92 19:34:09 GMT References: <1992Sep28.164439.15002@access.digex.com> Organization: U of Toronto Zoology Lines: 35 Sender: news@CRABAPPLE.SRV.CS.CMU.EDU Source-Info: Sender is really isu@VACATION.VENARI.CS.CMU.EDU In article jbh55289@uxa.cso.uiuc.edu (Josh 'K' Hopkins) writes: >>... said that budget constraints forced it's retirement >>not damage. it was damaged, but not totalled. also they siad that >>the damage was avoidable and that they could fix and work their way >>up to mach 8, maybe higher... so to test scramjet technology. > >My informationa says the A-2 was "damaged to an irreperable degree," ... Miller's "The X-Planes" says "...some serious damage, not the least of which was the heat damage in the ventral fin area, and some additional heat-related damage to other parts of the basic structure. In light of these problems [the heat damage, the poor performance of the ablator, and the loss of the dummy scramjet], and in consideration of the fact that ... X-15A-2 was obviously nearing the end of its service life, a decision was made to ground it..." >>does anyone know what the Vmax for the X-15 was? ... >Top speed was 4,519 mph (7,273 kph) acheived by William Knight. I don't >know what the structural limits were... Design top speed for the original X-15s was 6600 ft/s, 4500 mi/hr, about Mach 7. When X-15-2 crashed, it was rebuilt into X-15A-2, with stretched fuselage and provision for external tanks. The A design was intended for Mach 8 maximum, although 6.7 was the highest actually achieved, on a mission specifically aimed at maximum speed. There was some design work done on a delta-wing X-15 meant for Mach 8. Before anyone gets too intoxicated about reviving the program, do remember that the fin-mounted scramjet on X-15A-2 was *not* capable of propelling the aircraft to any useful extent, and never would have been. It was purely an experiment. An X-15 *powered* by a scramjet would have required major redesign. -- 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 ------------------------------ End of Space Digest Volume 15 : Issue 263 ------------------------------