Date: Thu, 17 Dec 92 05:09:22 From: Space Digest maintainer Reply-To: Space-request@isu.isunet.edu Subject: Space Digest V15 #561 To: Space Digest Readers Precedence: bulk Space Digest Thu, 17 Dec 92 Volume 15 : Issue 561 Today's Topics: Aurora DC vs Shuttle capabilities what the little bird told Henry 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: 16 Dec 92 15:21:32 From: Steinn Sigurdsson Subject: Aurora Newsgroups: sci.space In article nickh@CS.CMU.EDU (Nick Haines) writes: In article <1992Dec15.141754.9124@spider.co.uk> colint@spider.co.uk (Colin Tinto) writes: [Aurora sightings off Scottish Western Isles, speculated Aurora range of 5000 miles] Hang on - 5000 miles - that means it can just reach Scotland from the East Coast USA before having to turn back ? Something not quite right... Assuming that it's launching from the continental USA. Seems much more likely to me (given the sightings over the Netherlands as well) that one of the long-runway US bases in the UK or Germany is `home' to an Aurora. Nah, not isolated enough, rumour seems to be that the forward base is a US NATO base in Scotland. | 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: 17 Dec 92 03:21:07 GMT From: Greg Moore Subject: DC vs Shuttle capabilities Newsgroups: sci.space In article ewright@convex.com (Edward V. Wright) writes: >In strider@clotho.acm.rpi.edu (Greg Moore) writes: > >> You missed my point. If your crew compartment is in the cargo >>bay, where do you put the satellite? > >If your cargo bay is full of troops, where do you put the transport >vehicles? > >Answer: In the other airplane. > Gee, thanks for the snide answer. Now, my original point was on rendezvous and repair. So, now we have to get 3 objects in close proximity to each other. You've just made the problem at least 50% tougher. And now you have to transfer between craft. More difficuly. > >> Granted, but that's not what I meant. Will you have enough time >>to rendevous and capture the satelite? It took what 3 days for the >>shuttle to capture Intelsat VI? That's aday more than DC-?. >>Also, what type of fuel margin would DC-1 have for IN-orbit >>manevours? > >That's what tankers are for. > Again, another craft. > >> Use it yes, but use it for what it can be used for economically. >>Let's see, we've added an airlock, an arm, additional on-orbit capacity. >>Hmm, that adds up, and add complexity. Yes, let's ok at possibilities, >>but not claim t they are definites. > >Take a look at the C-130 Hercules. How many variants are flying, >in both military and commercial service? Hint: It's a lot more >than four. > Hint, they are flying. You are talking about a paper=airplane and saying it will do all this and more. I'm saying, build it, fly it, and see what happens. > >> I have a question about this. EOT and LM should require roughly >>the same amount of fuel, no? (as I recall, the energy to get into lunar >>orbit is about the same as GEO? I'm ignoring landing here). But how >>economical is it to transport that fuel TO orbit? Am I correct in >>remembering you saying about 10 DC-1 flights? > >Depends on your assumptions. I've done some back-of-the-envelope >calculations. If you can set up an oxygen-extraction plant on the >Moon, your costs go way down if you land the DC with its LOX tank >dry. (This would allow the DC to carry extra cargo, probably >using external attach points.) It might even be advantageous >to put payloads into GEO from the Moon instead of directly from >the Earth. > Right, that works fine once you've built your power-plant on the moon. I'm talking at first. It seems to me that someone here is forgetting the middle step of testing and flying the thing. > >>What about thermal protection. LM won't require any to land on >>the moon, but what about reentering earth orbit or earth landing? > >But the DC-LM will require periodic maintenance and, until you >have a fully equipped service station on the Moon, that will >require bringing it back to Earth. > Right, but what are your thermal protection requirements? Are they higher? If so, will the current system work? If not, what? Gee, don't want to use shuttle tiles... that would affect your turn-around. :-) > > ------------------------------ Date: Wed, 16 Dec 1992 22:14:10 GMT From: "Edward V. Wright" Subject: what the little bird told Henry Newsgroups: sci.space In <1992Dec16.124640.29309@ke4zv.uucp> gary@ke4zv.uucp (Gary Coffman) writes: >Where did I say that? If Saturn had pogoed just a little harder, >the Apollo program would have been dead in the water with no one >killed, and no one on the Moon either. Like it or not, Apollo *worked*. Can you name a program of similar size and complexity, using your new, improved, failure- oriented management system, that did as well. >Neither the Soviets nor the US had serious contingency plans in >place in the race to the Moon. Oh? Diverting an Earth-orbital mission (Apollo 8) into a circumlunar flight, because of a rumor that the Soviets were going do it first, sounds like a contingency plan to me. Unless you're rewriting history again. >Either critical systems worked as planned, or the program >failed. One of the Soviet critical systems did fail, ours did >not. So we "won", but it wasn't a rational way of running a >developmental program to deliver a reliable, economical launch >system. That's why we don't fly Saturns today. Yes, you're definitely rewriting history, again. ------------------------------ End of Space Digest Volume 15 : Issue 561 ------------------------------