#71
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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. |
#72
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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 |
#73
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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 |
#74
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"Pat Flannery" wrote in message
... 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. Whereas Saturn V carried all components up with it, ensuring that if one component went tits up, all of the others would too - including the crew. |
#75
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On Tue, 10 May 2005 14:20:24 GMT, h (Rand
Simberg) wrote: Last time I had a house built, I don't recall demanding that it be delivered assembled on a giant truck. ....Damn. There goes my theory that you really are nothing but trailer trash posing as a journalist :-( OM -- "No ******* ever won a war by dying for | http://www.io.com/~o_m his country. He won it by making the other | Sergeant-At-Arms poor dumb ******* die for his country." | Human O-Ring Society - General George S. Patton, Jr |
#76
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On Mon, 09 May 2005 23:59:21 -0500, Pat Flannery
wrote: Meanwhile, from far-off Hawaii, Jeffrey Bell looks at the CEV plan- surprisingly, he doesn't like it ;-) : ....Someone needs to explain to Bell his urgent need to simply shut the **** up. Preferably with a large baseball bat. OM -- "No ******* ever won a war by dying for | http://www.io.com/~o_m his country. He won it by making the other | Sergeant-At-Arms poor dumb ******* die for his country." | Human O-Ring Society - General George S. Patton, Jr |
#77
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Rand Simberg wrote:
Last time I had a house built, I don't recall demanding that it be delivered assembled on a giant truck. So I'm guessing you didn't buy a modular home? -- Reed Snellenberger GPG KeyID: 5A978843 rsnellenberger-at-houston.rr.com |
#78
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On 2005-05-10, Neil Gerace wrote:
"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. The analogy isn't quite the same, though - this would be equivalent to saying that there's a dead-zone during takeoff where you can't try to do an emergency landing of the airliner, surely? -- -Andrew Gray |
#79
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On 10 May 2005 12:35:13 GMT, Andrew Gray
wrote: The analogy isn't quite the same, though - this would be equivalent to saying that there's a dead-zone during takeoff where you can't try to do an emergency landing of the airliner, surely? Isn't that what happened to the Air France Concorde? Too fast and far down the runway to abort, not enough power to successfully take off. |
#80
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"Darren J Longhorn" wrote in message
... Isn't that what happened to the Air France Concorde? Too fast and far down the runway to abort, not enough power to successfully take off. I think it did actually take off, but could not go around properly because control was lost due to the fire. |
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