#51
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Pat Flannery wrote:
Ed Kyle wrote: "http://yarchive.net/space/shuttle/launch_abort.html" Oh, that's pleasant! Did they tell the crew about the little fire problem? I'm almost certain they did, since emergency crew evacuation (slide wire and all) was being considered. But the potential seriousness of the whole event was understated so much that I'm not even sure the news media picked up on it. The abort itself was news enough, because it fed into the "shuttle isn't working - NASA isn't able to get it off the ground - can't meet schedule" story of the time. (Which turned into the "NASA is too schedule-driven" story after Challenger disentegrated.) - Ed Kyle |
#52
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On Tue, 10 May 2005 09:19:45 +0800, in a place far, far away, "Neil
Gerace" made the phosphor on my monitor glow in such a way as to indicate that: " wrote in message ups.com... the DIV has to fly an odd trajectory (due to structural concerns) that means that there are points in the ascent when abort is *not* survivable. Is that bad? Seems to me that it happens to STS as well. Which is one of the several reasons that STS (to the surprise of many) is not "human rated." |
#53
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Alan Anderson wrote: Yes. So? A lot of launches is not a problem. It's a *goal*. It leads to a lot of assembly in orbit, more expense due to having to design the vehicle in smaller pieces, and greater odds one component won't make it to orbit, botching the whole assembly process- then there is the turn-around time of the launchpad to consider. Their is also the problem of how to get all the parts successfully rendezvoused and docked in orbit- each must have its own guidance and RCS systems to bring everything together in one spot in orbit- that means that the assembled multipart spacecraft will have excessive guidance and RCS systems and their weight attached to it...or at least carried with it into orbit, like the way the Soviet Kvant module was brought to Mir via the jettisonable FGB space tug: http://www.astronautix.com/craft/kvant.htm Pat |
#54
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Pat Flannery wrote: Ed Kyle wrote: Kliper, proposed as a Soyuz replacement, but able to carry up to six, is projected to weigh 13-15 tons, but its propulsion system will not be recovered (Lockheed has proposed to make the CEV hardware recoverable). NASA has listed the maximum liftoff mass of CEV, including escape systems and fairings that would not go into orbit, to be 20 tons. CEV doesn't have to weigh that much, of course. Kliper was too heavy for a Soyuz booster, and was to use an uprated Onega booster- a Soyuz booster with a new LOX/LH2 upper stage. This was later changed to the Zenit booster, which means you could theoretically launch Kliper from a modified Sealaunch pad. It's about time Russia accepted Zenit for what it is - maybe the world's most perfectly conceived (if not perfectly executed) space launcher. It is the rocket that NASA would like to have for CEV - kind of like an Atlas V on steroids - able to boost a 14-15ish ton payload to low earth orbit with no solid booster augmentation. It is the capability Russia is trying, unneccessarily, to copy with its Angara program. China and Japan would like to have such a rocket, but they don't. Europe had to work hard to get its Zenit (Ariane 5G) working. Ukraine and Russia have had the perfect machine for nearly 20 years. They just haven't used it. - Ed Kyle |
#55
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"Ed Kyle" wrote in news:1115700375.069758.129750
@f14g2000cwb.googlegroups.com: It's about time Russia accepted Zenit for what it is - maybe the world's most perfectly conceived (if not perfectly executed) space launcher. It is the rocket that NASA would like to have for CEV - kind of like an Atlas V on steroids - able to boost a 14-15ish ton payload to low earth orbit with no solid booster augmentation. It is the capability Russia is trying, unneccessarily, to copy with its Angara program. China and Japan would like to have such a rocket, but they don't. Europe had to work hard to get its Zenit (Ariane 5G) working. Ukraine and Russia have had the perfect machine for nearly 20 years. They just haven't used it. The Zarya 'super-Soyuz' would have been a great complement. The FSU blew its budget on Buran instead. --Damon |
#56
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Ed Kyle wrote: It's about time Russia accepted Zenit for what it is - maybe the world's most perfectly conceived (if not perfectly executed) space launcher. It is the rocket that NASA would like to have for CEV - kind of like an Atlas V on steroids - able to boost a 14-15ish ton payload to low earth orbit with no solid booster augmentation. It is the capability Russia is trying, unneccessarily, to copy with its Angara program. China and Japan would like to have such a rocket, but they don't. Europe had to work hard to get its Zenit (Ariane 5G) working. Ukraine and Russia have had the perfect machine for nearly 20 years. They just haven't used it. I think it got sort of sidetracked when Energia went down the tubes, followed by the Soviet Union going down the tubes. It's a very impressive rocket looking for a very impressive payload to carry. Meanwhile, from far-off Hawaii, Jeffrey Bell looks at the CEV plan- surprisingly, he doesn't like it ;-) : http://www.spacedaily.com/news/oped-05zl.html Pat |
#57
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On Tue, 10 May 2005 10:14:53 +0800, in a place far, far away, "Neil
Gerace" made the phosphor on my monitor glow in such a way as to indicate that: "Rand Simberg" wrote in message .. . Which is one of the several reasons that STS (to the surprise of many) is not "human rated." Well, it happens to airliners too. An abort (all engines out, no control surfaces responding) is often not survivable. But they are still allowed to fly. Because, unlike a vehicle that has to be essentially rebuilt each time, and only flies a few times a year (if that), they are reliable. |
#58
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Neil Gerace wrote:
" wrote in message ups.com... the DIV has to fly an odd trajectory (due to structural concerns) that means that there are points in the ascent when abort is *not* survivable. Is that bad? Seems to me that it happens to STS as well. From what I've been told, the thing is that if something goes goofy and they hit the abort button, there are points in the launch trajectory that result in the capsule (as that's what was assuemd at the time) hitting the ground/water at unsurvivably high speed. |
#59
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How about hanging 2 shuttle SRBs on each side of a Delta IV core?
Launch on the solids only a la Titan 4, airstart the CBC at altitude (ok some nozzle work required there). Maybe add one of the new higher powered upper stages when (if) they come on line. For cargo only flights of course, this combo has gotta have a decent throw weight. Phil |
#60
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Hi All
"Henry Spencer" wrote in message ... BAe's Multi-Role Capsule design, done in the mid-80s, with a capacity of four people for normal flight and six in a lifeboat configuration, almost entirely reusable (including propulsion), had an estimated launch mass of 8t including escape tower. I seem to recall you've mentioned this (the BAe M-R capsule) before, Henry. Do you have more info on this design? The only reference I could get through Google is you: http://www.spacebanter.com/q-t_5821-...aceflight.html However, using some manual labor I found this: http://www.astronautix.com/craft/mulpsule.htm ? Is this the beastie, you are referring to, Henry? Looking elsewhere on http://www.astronautix.com: Apollo CM: (info copied from http://www.astronautix.com/craft/apollocm.htm. Thanks Mark Wade!) Crew Size: 3. Maximum Diameter: 3.90 m. Habitable Volume: 6.17 m3. Mass: 5,806 kg (Structure Mass: 1,567 kg, Heat Shield Mass: 848 kg, Reaction Control System: 400 kg, Recovery Equipment: 245 kg, Navigation Equipment: 505 kg, Telemetry Equipment: 200 kg, Electrical Equipment: 700 kg, Communications Systems: 100 kg, Crew Seats and Provisions: 550 kg, Crew mass: 216 kg, Miscellaneous Contingency: 200 kg, Environmental Control System: 200 kg.) RCS Coarse No x Thrust: 12 x42kgf. RCS Propellants: N2O4/UDMH. RCS Isp: 290 sec. RCS Impulse: 26,178.00 kgf-sec. Main Engine Propellants: n/a. Main Engine Propellants: 75 kg. L/D Hypersonic: .3. Electrical System: Batteries. Electric System: 20.0 kWh. Battery: 1,000.0 Ah. Now given that this is 1960s technology (and some of its was 1950s tech), and given that the CM could apparently have accomodated 5 couches instead of three if used purely for LEO ops, why is NASA even thinking about granting contracts for a CEV? I know this is not a new idea but why not just dust off the boilerplates and blue prints for the CM? Scan the blue prints into an industrial CAD package. Dismantle every piece of existing hardware that remains. X-ray it, photograph it, measure it, wiegh it, do what ever you can to find out how to reproduce it. Combine this data with the modernized CAD drawings. Use a modern CNC machine to cut the majority of the parts, or to at least make the templates. Replace all the 1960s electronics, life support and reaction control with 1990s stuff. You can probably build in triple or quadruple redundancy, and still end up using less mass and power than the original parts. You can probably drop 25% of heat shield mass because the Apollo Mk2 doesn't have return to the atmosphere directly from lunar orbit. Use modern space-rated materials for the hull and structure. How light can you make this thing? Of cause the CM is almost useless without the SM, which according to http://www.astronautix.com/craft/apollosm.htm has a mass of 24,523 kgs, but 18,413 of that is fuel for lunar orbit insertion. That is over six tons of dry mass. But the Gemini Adaptor- and Equipment- Modules only have a combined mass of 1868 kgs according to http://www.astronautix.com/craft/gemini.htm. Even if this needs to be doubled for the Apollo Mk2, the vehicle would still come in at less than 10,000 kgs for a five seater LEO crew delivery vehicle. Has anyone got any figures on the Skylab Service Modules? I couldn't seem to find them on http://www.astronautix.com/. Rip out the seats and the life support and you got Apollo Mk2 'Progress model' (you can drop the heat shielding too if you want to make it disposable like the Russians did with Progress). Going with Apollo CM type figures that would give you a vehicle with 6 cubic meters of cargo space, and 2261 kgs of cargo space (if you're going for disposability 1093 kgs less if you want to recover the capsule). A new Apollo capsule should sit nicely on top of the Atlas V (with its five meter maximum diameter fairing) and the Atlas van deliver 12,500 kgs to a 185 km orbit at 28.5 degrees (someone can tell me whether this is ISS-compatiable). The design is already proven, just update the parts you can't get anymore or know you can safely replace with something better. Fly it (unmanned, without the seats or heat shield , filled with cheap disposable cargo) to ISS, as a proving exercise. If it works, then fly a second one and try to recover it this time. If that works risk a couple of volunteer astronauts on it. I know reviving a 40 year old design is not as sexy (and probably not as lucrative) as designing and building a new vehicle, but, at least, of late the people who get paid to deliver the new vehicles have a poor record on deliver (X-33). Maybe NASA should get its money back if its contractors fail to perform ;-). Isn't that the way it works in the REAL WORLD. Get ISS (and NASA) and alternative, safe and expandable crew and cargo delivery system and then start thinking about how to extend it's usefulness to lunar missions. If you still need to do lunar missions once you've got this vehicle up and running launch a lunar insertion stage seperately and do an on-orbit rendezvous. If you need an LM, launch seperately and dock with that too. -- "Think outside the box -- the box isn't our friend." | Henry Spencer -- George Herbert | Thanks and regards Frank Scrooby |
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