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High-flight rate Medium vs. New Heavy lift launchers
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#22
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High-flight rate Medium vs. New Heavy lift launchers
"Gordon D. Pusch" wrote in message ... "Krzys Kotwicki" writes: I've only caught this thread at the last minute, so I really don't know if this has been mentioned yet, it probably has, but why not use the Energia HLLV or an Americanized derivative, Mmmmm, more like the DEA factor - "Doesn't Exist Anymore". -Kim- |
#23
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High-flight rate Medium vs. New Heavy lift launchers
"ed kyle" wrote in message om... Interesting. Note that a fully fueled Delta IV 5-meter diameter second stage weighs nearly 31 metric tons (less than 4 tons empty), several tons in excess of what Delta IV-Heavy is reported to be capable of boosting to low earth orbit. The logical approach would be to upgrade Delta IV-Heavy enough to be able to put 31 tons into LEO so that these stages could be orbited fully fueled. This two-stage plus CEV stack, which appears capable of translunar insertion, would then require three Delta IV- Heavy launches. Trouble is, Delta IV isn't exactly suited to salvo launch operations. For that matter, neither is Atlas V. Both would require additional facilities to make such a mission achievable. From the look of budget numbers, there won't be enough money to take that approach. Using just existing facilities would lead to some components having to wait in orbit for quite some time before the mission package is assembled. Now, that may not be a huge challenge but it does complicate things, particularly if cryogenic fuels are used. -Kim- |
#24
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High-flight rate Medium vs. New Heavy lift launchers
"Kim Keller" wrote in message .com...
"ed kyle" wrote in message om... Interesting. Note that a fully fueled Delta IV 5-meter diameter second stage weighs nearly 31 metric tons (less than 4 tons empty), several tons in excess of what Delta IV-Heavy is reported to be capable of boosting to low earth orbit. The logical approach would be to upgrade Delta IV-Heavy enough to be able to put 31 tons into LEO so that these stages could be orbited fully fueled. This two-stage plus CEV stack, which appears capable of translunar insertion, would then require three Delta IV- Heavy launches. Trouble is, Delta IV isn't exactly suited to salvo launch operations. For that matter, neither is Atlas V. Both would require additional facilities to make such a mission achievable. From the look of budget numbers, there won't be enough money to take that approach. If the money isn't there, then the U.S. is not going to the Moon. Any lunar mission is going to require new launch facilities, whether it be via EELV or not. The most efficient way to salvo launch is to assemble vehicles (ideally with payloads) off-pad in an assembly building, then scoot 'em and shoot 'em off of one or two pads. An extra one or two VIF bays could turn SLC 41 into a salvo launcher. NASA, of course, will have an unused assembly building with a pair of launch pads after 2010. The old Air Force Titan ITL complex and Pad 40 will be available after this year or next, as will SLC 36A and B. If NASA doesn't build a new pad somewhere, Cape Canaveral/KSC will be left with only four or so active launch pads in a few years, less than half of today's number. Using just existing facilities would lead to some components having to wait in orbit for quite some time before the mission package is assembled. Now, that may not be a huge challenge but it does complicate things, particularly if cryogenic fuels are used. A lunar surface rendezvous approach could offer some relief. Sending some mass directly to the lunar landing site ahead of the manned mission would reduce the LEO-rendezvous mass requirements and reduce launch window restraints. - Ed Kyle |
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High-flight rate Medium vs. New Heavy lift launchers
"Kim Keller" wrote in message .com...
"ed kyle" wrote in message om... Interesting. Note that a fully fueled Delta IV 5-meter diameter second stage weighs nearly 31 metric tons (less than 4 tons empty), several tons in excess of what Delta IV-Heavy is reported to be capable of boosting to low earth orbit. The logical approach would be to upgrade Delta IV-Heavy enough to be able to put 31 tons into LEO so that these stages could be orbited fully fueled. This two-stage plus CEV stack, which appears capable of translunar insertion, would then require three Delta IV- Heavy launches. Trouble is, Delta IV isn't exactly suited to salvo launch operations. For that matter, neither is Atlas V. Both would require additional facilities to make such a mission achievable. From the look of budget numbers, there won't be enough money to take that approach. Using just existing facilities would lead to some components having to wait in orbit for quite some time before the mission package is assembled. Now, that may not be a huge challenge but it does complicate things, particularly if cryogenic fuels are used. -Kim- Any idea how much time? I was thinking that the current "Heavies" can lift about 25 tons to LEO. Two of these could put about 10 tons on the moon. One would put up an upper stage (20-25 tons) which would dock with the Lander (10 tons) plus cargo(10 tons). |
#26
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High-flight rate Medium vs. New Heavy lift launchers
If we do get sucked into the path of building heavier launchers,
then perhaps the question is, how to do so in the most cost-effective manner. Is it easy to increase the diameter of the Delta IV or Atlas 5 to a 6 meter diameter (Atlas/Delta 6 anyone)? Or would it be more efficient to just strap on solids? It has also been said that the first stage is the cheapest, so perhaps the real debate should be on how much we incrementally launch to LEO each time. High-flight rate is important to the economics, and the assumption is that we want to make this step on a *permanent* basis this time, vs. the transitory nature of Apollo. Seems to me there is still an awful lot of unused capacity in the medium lift marketplace - and development costs for the EELVs that haven't been amortized. Apart from higher energy upper stages, which seem to be part of the Delta IVs future at least, isn't there a way to tweak the specific impulse of the RS-68 even a little bit? I believe the H-1 and the F-1 were both incrementally upgraded over the course of their lives with considerable payoffs in lofting capacity. Any ideas, insights? Phil |
#27
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High-flight rate Medium vs. New Heavy lift launchers
"ed kyle" wrote in message om... If the money isn't there, then the U.S. is not going to the Moon. You may very well be right. Bush did what makes himself look good, not what insures the project will survive future administrations. Any lunar mission is going to require new launch facilities, whether it be via EELV or not. More than likely. The most efficient way to salvo launch is to assemble vehicles (ideally with payloads) off-pad in an assembly building, then scoot 'em and shoot 'em off of one or two pads. An extra one or two VIF bays could turn SLC 41 into a salvo launcher. We priced that option this past summer. Even that ain't cheap. NASA, of course, will have an unused assembly building with a pair of launch pads after 2010. Yeah. That's why I think there'll be a push to develop Shuttle-C or something similar. The old Air Force Titan ITL complex and Pad 40 will be available after this year or next, as will SLC 36A and B. We looked at modifying SLC-40, too - there are a lot of "landmines" that would drive up the cost and stretch out construction schedules. Bottom line was it would cost a lot of money to turn -40 into something usable. As for -36, a line was drawn on the CCAFS map with the words, "No Heavy Rockets South Of This Line" above it. That line was a bit north of -36. If NASA doesn't build a new pad somewhere, Cape Canaveral/KSC will be left with only four or so active launch pads in a few years, less than half of today's number. Just how many do we need? -Kim- |
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High-flight rate Medium vs. New Heavy lift launchers
"Alex Terrell" wrote in message om... Any idea how much time? Probably a month, given no expansion of today's facilities. -Kim- |
#29
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High-flight rate Medium vs. New Heavy lift launchers
Phil Paisley wrote:
Apart from higher energy upper stages, which seem to be part of the Delta IVs future at least, isn't there a way to tweak the specific impulse of the RS-68 even a little bit? I believe the H-1 and the F-1 were both incrementally upgraded over the course of their lives with considerable payoffs in lofting capacity. You could use FLOX . But I doubt that works well in a hot-oxidizer staged combustion cycle. Maybe gelled metalized RP-1 for the fuel? Adds about 5% to the Isp. Paul |
#30
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High-flight rate Medium vs. New Heavy lift launchers
On Sat, 07 Feb 2004 06:28:15 GMT, in a place far, far away, "Kim
Keller" made the phosphor on my monitor glow in such a way as to indicate that: "ed kyle" wrote in message . com... If the money isn't there, then the U.S. is not going to the Moon. You may very well be right. Bush did what makes himself look good, not what insures the project will survive future administrations. Just assuming for the sake of argument that you're right (though there's little reason to think so), just what should he have done instead? |
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