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#126 2005-04-14 07:01:10

GCNRevenger
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From: Earth
Registered: 2003-10-14
Posts: 6,056

Re: Post central for information on CEV III - Continued from previous

Not meaning you SpaceNut, you posted while I was writing.

The reality of the situation is that NASA has only about $10Bn a year to spend on spaceflight. If more then 20-25% of this is soaked up by launch costs, NASA isn't going anywhere ever.


[i]"The power of accurate observation is often called cynicism by those that do not have it." - George Bernard Shaw[/i]

[i]The glass is at 50% of capacity[/i]

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#127 2005-04-14 17:13:07

Michael Bloxham
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From: Auckland, New Zealand
Registered: 2002-03-31
Posts: 426

Re: Post central for information on CEV III - Continued from previous

No, because any additional expense relating to SDV will be offset with less time and money wasted mucking around on the moon. If you asked for a loaf of bread, would you accept a stone instead? Even if the stone was free? It doesn't matter how much cheaper or easier the moon is, because the goal is Mars.


- Mike,  Member of the [b][url=http://cleanslate.editboard.com]Clean Slate Society[/url][/b]

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#128 2005-04-14 19:50:45

GregM
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Registered: 2005-01-16
Posts: 30

Re: Post central for information on CEV III - Continued from previous

The new NASA administrator has publicly stated that he cannot envision doing the VSE without an extremely heavy lift capability. Folks can safely assume that he wants it now that he is in charge. Probably looking at a LV in the 75-100 ton payload range.

The pad facilities for Delta 4 and Atlas 5 are not set up for such a heavy lift vehicle, and processing facilities for payloads of such scale are non-existent anywhere at CCAFS. Upgrading the pad and facilities to accommodate such an upgrade, in addition to the actual vehicle upgrades (which would be huge) would be bloody expensive and difficult – if at all possible.

At the end of the Shuttle era there will be literally billions and billions of dollars of launch facilities and processing infrastructure capable of dealing with vehicles and payloads of such scale and sophistication, and hundreds or thousands of trained employees with nothing to do.  Does anyone realistically think that they will junk LC-39, the VAB, the LCC, and the OPF?? These are the only facilities like this in the world. Hell, the VAB can process 2 and possibly 3 launch vehicles at once indoors. Unbeatable flexibility.

The shuttle SRB’s are stastically the safest large rocket in the world. One failure in some 220 launches. Nothing beats that – hands down. They would be excellent candidates as LV’s for the CEV. Launch delays due to LV problems on the pad would be few and far between.

My money is on the following scenario:

1) A very heavy lift LV is derived from STS components. Likely 2 or 4 STS SRB’s (possibly extended by a segment).  First stage of the core vehicle is based on the STS ET, with engines placed inline underneath. The engines are likely to be 3-4 RS-68’s, as no one wants to have to rely on the steady supply of Russian built engines (as good as the RD-180 is). By sticking with the RS-68’s, LC-39’s oxygen/hydrogen facilities can remain in service. On top of the ET will be a second stage, likely a loosely based on a Delta 4 or Atlas 5 upper stage (they both use the same engine system from the Centaur program), with 3-6 RL-10 type engines. Such a vehicle could give a payload fairing up to 7 to 8 meters in diameter, something that an EELV will never be able to accommodate. The vehicle will be processed and stacked at the VAB, and launched out of LC 39. Looking at 2 to 4 launches per year.

2) Constellation CEV launched by a LV consisting of a single STS SRB first stage, and an upper stage more directly derived from Delta 4 or Atlas 5 upper stage, with likely 2-3 RL-10 type engines. The LV and spacecraft will be processed at the OPF/VAB, and launched out of LC-39. Launch rates could be very high, as the processing for such a LV would be quite fast.

3) EELV’s used to launch Constellation’s unmanned payloads in the 15-25 ton range with diameters under 5 meters. Once things get started, there will be plenty of need for such services. Lots of things under 75 tons will need launch services in the Constellation project – and this is exactly the role that EELV’s were designed to do.

Just my 2 cents 
tongue

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#129 2005-04-14 20:37:05

GCNRevenger
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Re: Post central for information on CEV III - Continued from previous

No, because any additional expense relating to SDV will be offset with less time and money wasted mucking around on the moon. If you asked for a loaf of bread, would you accept a stone instead? Even if the stone was free? It doesn't matter how much cheaper or easier the moon is, because the goal is Mars.

Nope. Because even if we DO set out for Mars, the SDV program will be so expensive that we won't be able to do much more then a flags/footprints mission and go home. Way to go.


[i]"The power of accurate observation is often called cynicism by those that do not have it." - George Bernard Shaw[/i]

[i]The glass is at 50% of capacity[/i]

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#130 2005-04-14 20:50:54

GCNRevenger
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From: Earth
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Posts: 6,056

Re: Post central for information on CEV III - Continued from previous

The new NASA administrator has become infatuated by SDV, which may have made him blind about the Shuttle's accursed legacy of failure... Trying to take an exsisting system which has been a disaster from day one and making it a sucess? I would rather side with the system that we know that works.

I fear that Griffin is a d***ed Shuttle-Hugger, who simply cannot let go of the STS and fully accept that it is a failure, and very likly cannot ever be made to work with or without the Orbiter. The moron is even considering a Hubble mission.

We don't need heavy lift for a Lunar program. We don't need it. 50MT-class launchers can do the job just fine. Delta can do this without radical alteration, on budget, and on flight rate. All facilities basically exsist already.

Building the SRB launcher? I don't like the sound of that, because there is no hope of engine shutoff in the event of an emergency. The main #1 lesson paid for by the victims of the Shuttle fraud was that you DO NOT rely on the reliability of the system for crew survival whenever possible. The SRB launcher will limit escape options.

And if we do build the SRB launcher, there would then be no need for a medium EELV.


[i]"The power of accurate observation is often called cynicism by those that do not have it." - George Bernard Shaw[/i]

[i]The glass is at 50% of capacity[/i]

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#131 2005-04-14 20:56:12

John_Frazer
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From: Boulder, Co. USA
Registered: 2002-05-29
Posts: 75
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Re: Post central for information on CEV III - Continued from previous

SHLV digression

This is far afield from central info for the CEV...

SDV means Shuttle-derived vehicle?
So that leave us with some sort of EELV to be funded and built for the CEV and the Moon missions, and an unknown, completely left-field SHLV for Mars? Or is a Mars mission to be built up in LEO from EELV delivered pieces of no bigger than 20 tons per shot?
(nand is the acronym HLV for 20 tons or so, while anything bigger is an SHLV?)

We really think a Shuttle-C variant couldn't be built and flown for less than the Shuttle launches we've known? I find that extremely difficult to swallow. With what we accomplished from zero to Apollo 11 in such a short time, we couldn't take the Shuttle-C from the designs to a launch prototype in less than 8 years or so? This thing has been called the most studied and evolved concept in space travel history.
And it's totally useless -maybe worse than that?

Is theer a better thread for this? Something specifically related to HLV/SHLV concepts? I'd like to have a concise thread for the CEV info, but this is crazy. Every thread that is started to talk about such a limited topic devolves into everything frrom Shuttle-III to space elevators to asteroid mining.

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#132 2005-04-14 21:04:47

GCNRevenger
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Re: Post central for information on CEV III - Continued from previous

"We really think a Shuttle-C variant couldn't be built and flown for less than the Shuttle launches we've known? I find that extremely difficult to swallow."

Of course it would be cheaper, no dispute there. The problem is will it be cheap enough? For NASA to DO anything useful, then it needs to basically cut the price in half. I do not trust NASA to do this, since that would involve getting rid of signifigant numbers of engineers, which NASA has resisted doing tooth-and-nail for decades. The entire Shuttle infrastructure, much of it antique and left over from Apollo... too big and un-automated I think... is a stone round' our necks, not an asset.

So yes, unless NASA can suddenly change its ways about the make-work mindset, then Shuttle-Derived would be worse then useless, its cost would make doing anything with it impossible, but it would be un-cancelable like Shuttle.

You underestimate the performance of the EELVs as well. Boeing believes that with a few modest engine upgrades, that the Delta-IV can lift 40-50 metric tonnes. This would be only a modification of an exsisting flight-proven rocket with exsisting infrastructure, which has been sold for an affordable price even at a very low flight rate. Increasing the flight rate, which is very possible if the USAF goes in on "EELV+" with NASA, would drive down the costs even further. The low flight rate of SDV cannot take advantage of economies of scale nor competition between EELV builders.


[i]"The power of accurate observation is often called cynicism by those that do not have it." - George Bernard Shaw[/i]

[i]The glass is at 50% of capacity[/i]

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#133 2005-04-14 21:27:21

Ad Astra
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Re: Post central for information on CEV III - Continued from previous

The EELV proponents seem to be making the same argument von Braun made before 1962, while the SDV supporters are taking the Houbolt route.

For Apollo, Houbolt won out because his approach was feasable with the current technology and it offered the shortest development time.  Money was no object back then.  Roll the clock forward 43 years, and the world is turned on its head.  Money is the limiting factor, while the time  it takes is not really an issue.  If the return to the moon is a marathon rather than a sprint, an earth-orbit rendezvous approach will likely win out.

We shouldn't feel bad that this debate is still going on.  Even though NASa made a choice in 1962, it had to revisit the decision in 1989 for SEI.  Originally, EOR won out, but direct landing (using the Saturn-derived "Comet") was the preferred mission mode by 1990.  The question was never really settled back then, and that's why it's still festering today.


Who needs Michael Griffin when you can have Peter Griffin?  Catch "Family Guy" Sunday nights on FOX.

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#134 2005-04-14 23:01:26

Michael Bloxham
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From: Auckland, New Zealand
Registered: 2002-03-31
Posts: 426

Re: Post central for information on CEV III - Continued from previous

Damnit GCNR, NASA cannot afford to be dumping half of The Army as you require. They can't and they won't. And if there's not enough dough left over for a half-decent human space flight program, ...well then NASA is screwed. Woe is NASA!


- Mike,  Member of the [b][url=http://cleanslate.editboard.com]Clean Slate Society[/url][/b]

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#135 2005-04-14 23:39:29

John_Frazer
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From: Boulder, Co. USA
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Posts: 75
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Re: Post central for information on CEV III - Continued from previous

This thread is not and has never been a "clearinghouse for info on the CEV". People really need to observe proper netiquette about holding to a topic, or starting a new thread.

> The problem is will it be cheap enough? For NASA to DO anything useful, then it needs to basically cut the price in half. I do not trust NASA to do this, since that would involve getting rid of signifigant numbers of engineers, which NASA has resisted doing tooth-and-nail for decades. The entire Shuttle infrastructure, much of it antique and left over from Apollo... too big and un-automated I think... is a stone round' our necks, not an asset.

Actually, the ISS is the deadweight. The ISS can't be assembled by crews put up on CEVs (Soyuz for the time being) to assemble cargo put up by cheaper non-reusable boosters because each load needs to be integrated at once by the Shuttle itself. This dooms us to http://nasaproblems.com/#Pods]flying crews unprotected in the Shuttles as we have been.
20+ missions of EVA to assemble it, and we trust that we won't have another serious problem or program holding/extending problem that requires us to break word and keep the Shuttles flying past the deadline set by the CAIB report. (does anybody believe this?)

The army of people for Shuttle should be used to develop the CEV. If they can't be tasked with that, let them go and hire new people who can use the funding from the cut Shuttle program to build a CEV. Put others of the Shuttle army to work building and launching Shuttle-C for the big loads we need to do Lunar and Martian missions. For the money they've been using to launch 4-5 Shuttles a year, they could double the rate of Shuttle-C, keeping as many people on the jobs doing more useful work.

Question for anybody who can: How much of the ISS that still needs to be put up could be done with crews up there on a Shuttle or in the station itself (after it's gotten enough to let them do something other than housekeeping) assembling loads put up on unmanned, non-reusable Shuttle-Cs? Could we "finish the ISS" any faster or with less Shuttle flights?

(I speak specifically about only the Shuttle-C, because anything else like the Ares requires new ETs, and the Z variant requires ne ETs. The Shuttle-C uses everything we're using now, including vehicle stacking and handling, the rotating service arm, and the flame trenches. Nothing new about it but the dumb expendable cargo pod with expendable engines on the back.)

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#136 2005-04-14 23:53:36

John_Frazer
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From: Boulder, Co. USA
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Posts: 75
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Re: Post central for information on CEV III - Continued from previous

I'm appalled to see people seriously considering things for Lunar/Martian missions that make no sense.
Launching manned expeditions to stay on the Moon, using EELVs and rendesvous and assembly in LEO(RLEO)? LOR or LSR?
Sending to the Lunar surface a mass consisting of heatshields and landing aids meant for Earth orbit/launch safety/ISS crew fery, which are nothing but deadweight on the Moon?
Lunar Orbit Space Stations, which have been determined to be a real LOSS, since it would need continual orbit adjustment changes and crewed habitation? When a LEO station has taken us 30 years and uncounted tens of billions and still it's in doubt.

Lunar ISRU, when there is no point in using the Moon as a "steppingstone" for Mars?

Mars Direct architecture equipment modified for Lunar exploration makes more sense. SHLV development for direct throw of cargo loads to the Moon, to be met by crews makes some sense, but not in small EELV increments. 50T-LEO? We should not think of settling for less than 80-120T-LEO for Lunar missions.

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#137 2005-04-15 05:11:38

SpaceNut
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Re: Post central for information on CEV III - Continued from previous

Part of the problem is that nothing was ever built from the shuttle c or any other flavor.  A full scale mockup back in 1989 was built to which is a shame for it would supplement the shuttle greatly with the role of building the ISS. As for cost I agree that the shuttle's army of personel does add to the cost but is it just the wages or is it the process of build that is making it rise. Processing only for a few shuttle runs make each one very costly for the yearly budget.
We know the cost of the External tank ($40M) and the Srb's ($30 -50M) but where is all the extra cost coming from other than the orbitor refurbishment. It comes from the average number of flights per year divide into all of the budgets dollars for shuttle.
All this is supposed to be done by the contractor United space alliance so how much is being done by Nasa and its army for shuttle that seems to be the problem. The next question is why is it not being done by the contractor?

So what would a shuttle c cost built entirely by the contractor? How many of them could be delivered per year?

Now that thanks care of cargo version of CEV but it is the manned limitation of only 20M tons that concerns me. For that does not leave very much in the way of resources with out a cargo vehicle to go with it for support while in flight to any destination. So does this mean the olde dock the CEV manned vehicle with a cargo supply carrier in LEO?

Edit Shuttle Z comparison to Shuttle C

Shuttle-Z was Shuttle-C on steroids, the ultimate development of the shuttle to be used to put Mars expeditions into orbit. It would use 4 SSME's, and a third stage with 181,000 kg of propellant powered by 1 SSSME. But such designs would require new handling facilities due to the extra height of the vehicle.

yshuttlz.jpg

The shuttle orbiter would be replaced by an unmanned recoverable main engine pod. The same concept was studied earlier as the Interim Heavy Lift Launch Vehicle (IHLLV) and as the Class I Shuttle Derived Vehicle (SDV). The Phase I two-SSME configuration would have a payload of 45,000 kg to low earth orbit. Design carried to an advanced phase in 1987-1990, but then abandoned when it was found the concept had no cost advantage over existing expenable launch vehicles.

yshuttc1.jpg

Note each had draw backs for why they were not considered. Having any of the SDV parts recovereable other than the SRB's would have caused its cost to rise most definitely. Making it entirely expendable would lower its cost.

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#138 2005-04-15 08:54:33

Commodore
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From: Upstate NY, USA
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Posts: 1,021

Re: Post central for information on CEV III - Continued from previous

Were going to spend a lot of money on the fancy aerodynamic shell and rockets of whatever we launch on a SDV.


"Yes, I was going to give this astronaut selection my best shot, I was determined when the NASA proctologist looked up my ass, he would see pipes so dazzling he would ask the nurse to get his sunglasses."
---Shuttle Astronaut Mike Mullane

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#139 2005-04-15 09:02:03

GCNRevenger
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From: Earth
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Posts: 6,056

Re: Post central for information on CEV III - Continued from previous

Michael Bloxham: "NASA cannot (politically?) afford to be dumping half of The Army as you require."

They can because they must, they have no other choice. The current plan is to begin drawing down The Army as the 2010 Shuttle retirement date aproaches. If NASA cannot resist keeping them around or insisting that they are nessesarry, then yes, NASA is doomed. Shuttle-derived really is that bad.

John_Frazier: "Actually, the ISS is the deadweight."

Wrong. This is not quite true. The ISS chews up a bit under $2Bn a year, less then half what the Shuttle nightmare does, Shuttle is still the biggest problem... In any event, NASA will need to cut both programs probobly. You cannot shift the blame for NASA's self-inflicted crippling on the ISS alone.

"The army of people for Shuttle should be used to develop the CEV..."

No. We simply don't need several thousands of engineers to develop a little six-tonne capsule and some rockets based directly on the RL-10/RL-60 engines. NASA needs to let them go and not hire new people to replace them. And fly 8-10 SDV shots a year? Thats just silly, there is no reason to, and the extra cost would be fatal.

"...(ISS) assembling loads put up on unmanned, non-reusable Shuttle-Cs?"

None, because it can't. Shuttle-C will not be maneuverable enough to rendevous with the ISS safely and accuratly.

"Nothing new about it but the dumb expendable cargo pod with expendable engines on the back."

Um. Building such an engine pod is kind of a big deal.

" Launching manned expeditions to stay on the Moon, using EELVs and rendesvous and assembly in LEO... 50T-LEO? We should not think of settling for less than 80-120T-LEO for Lunar missions."

Yes, thats correct. Any Lunar payload you launch on SDV will be about half TLI stage and half payload/lander stage. There isn't any good reason why these things can't be launched seperatly on a pair of EELV+ launchers, which will cost under half what SDV does. Docking is pretty easy.

"Sending to the Lunar surface a mass consisting of heatshields and landing aids meant for Earth"

It would include the fuel for Earth return too probobly... Which is exactly what would be done if the HLLV/Direct-Return arcitecture is selected, like M. Griffin's "Comet" megalauncher system (at signifigant payload penalty) and would not be done with an EELV+ EOR system.

Edit: I am beginning to think that there is a real irrational pathology going around that demands to find worth in the Shuttle program, perhaps as redemption for its failure in the face of being trumpeted as a national treasure, and willfully ignoring bad things about it.


[i]"The power of accurate observation is often called cynicism by those that do not have it." - George Bernard Shaw[/i]

[i]The glass is at 50% of capacity[/i]

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#140 2005-04-15 09:07:44

GCNRevenger
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From: Earth
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Posts: 6,056

Re: Post central for information on CEV III - Continued from previous

The EELV proponents seem to be making the same argument von Braun made before 1962, while the SDV supporters are taking the Houbolt route.

For Apollo, Houbolt won out because his approach was feasable with the current technology and it offered the shortest development time.  Money was no object back then.  Roll the clock forward 43 years, and the world is turned on its head.  Money is the limiting factor, while the time  it takes is not really an issue.  If the return to the moon is a marathon rather than a sprint, an earth-orbit rendezvous approach will likely win out.

We shouldn't feel bad that this debate is still going on.  Even though NASa made a choice in 1962, it had to revisit the decision in 1989 for SEI.  Originally, EOR won out, but direct landing (using the Saturn-derived "Comet") was the preferred mission mode by 1990.  The question was never really settled back then, and that's why it's still festering today.

There is a big difference between SDV and EELV+ other than the economies of scale: the difference is that the whole construction, integration, and launching of SDV is inherintly inefficent because it relies on outdated technology and methods.

Edited 11:57EDT


[i]"The power of accurate observation is often called cynicism by those that do not have it." - George Bernard Shaw[/i]

[i]The glass is at 50% of capacity[/i]

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#141 2005-04-15 10:55:23

RobertDyck
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From: Winnipeg, Canada
Registered: 2002-08-20
Posts: 7,814
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Re: Post central for information on CEV III - Continued from previous

I'm appalled to see people seriously considering things for Lunar/Martian missions that make no sense.
Launching manned expeditions to stay on the Moon, using EELVs and rendesvous and assembly in LEO(RLEO)? LOR or LSR?
Sending to the Lunar surface a mass consisting of heatshields and landing aids meant for Earth orbit/launch safety/ISS crew fery, which are nothing but deadweight on the Moon?
Lunar Orbit Space Stations, which have been determined to be a real LOSS, since it would need continual orbit adjustment changes and crewed habitation? When a LEO station has taken us 30 years and uncounted tens of billions and still it's in doubt.

Lunar ISRU, when there is no point in using the Moon as a "steppingstone" for Mars?

Mars Direct architecture equipment modified for Lunar exploration makes more sense. SHLV development for direct throw of cargo loads to the Moon, to be met by crews makes some sense, but not in small EELV increments. 50T-LEO? We should not think of settling for less than 80-120T-LEO for Lunar missions.

I think you'll find almost everyone here on this board supports going directly to Mars, not the Moon first. However, George W. said go to the Moon so NASA must go to the Moon.

Earth orbit rendezvous in LEO has the advantage that you can leave behind the heatshields and landing aids for Earth. Yes, they are dead weight on the Moon. No, you don't want to take them to the lunar surface.

Lunar Orbit Space Station? I think we can all agree that's just dumb. There's nothing in lunar orbit; no resources, no science, no lessons learned that can't be learned in LEO. In fact, I argue don't even stop a lunar vehicle in lunar orbit, go directly to the surface.

A lot of Mars hardware can't be used on the Moon. You can't use aerobraking or a parachute landing. Temperature control is more stringent on the Moon; Mars goes from 0°C to -80°C, the Moon goes from +123°C to -153°C. You can use Mars air to get rid of waste heat, the Moon has hard vacuum. Mars surface has dust storms and 1/4 the radiation of Mars orbit, the Moon has more radiation than Mars orbit. Mars has 38% gravity, the Moon has 16%. However, you can test the life support system, habitat layout, suits, etc. Lunar suits will require a micrometeor/thermal layer that also works in interplanetary space; Mars suits require a different scuff layer/thermal layer that works in atmosphere. The multiple layer aluminized mylar scuff layer used on all spacesuits to date works in vacuum but won't work in the atmosphere of Mars; Mars needs something like thinsulate from ski jackets. But the pressure layer and PLSS would work the same on both planets. Suit temperature control is again different.

SpaceNut: I agree that Shuttle C/Z would have been a great benefit to the shuttle program. However, I have to disagree that making the engine pod recoverable would have been a significant cost increase. How much would it really cost to use 3 existing SSMEs, 2 existing OMS pods, an enlarged X-38 parafoil, a COTS SBC (Commercial-Off-The-Shelf Single-Board Computer) designed for communications satellites, a single-piece ablative heatshield (Apollo technology), DurAFRSI developed by Ames and scheduled to be tested on X-37, composite fairing from Titan 4B/Ariene 5/Atlas 5/Delta IV, and adapt launch software from shuttle and landing software from X-38? However, I do have to emphasize the need to use at least 3 SSMEs and a fairing, don't use 2 SSMEs with a full cargo bay. The 2 SSME/cargo bay version could only lift 70-77 tonnes to LEO which makes the cost per pound to orbit high, and that version wouldn't recover the engine pod.

GCNRevenger: with 2 OMS pods, each with an RCS thruster pod, you can rendezvous with ISS. Without the nose thruster pod you can't dock, but you can rendezvous and stabilize cargo.

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#142 2005-04-15 11:02:59

BWhite
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From: Chicago, Illinois
Registered: 2004-06-16
Posts: 2,635

Re: Post central for information on CEV III - Continued from previous

Lunar orbit station would also be unstable, as I recall, and not easily maintained. L1 would seem the logical choice =IF= there were to be any forward base to support lunar exploration.

The ONLY reason for doing the Moon (beyond Bush said so) is to exploit lunar resources. Primarily PGM IMHO with lunar LOX exported to L1 and LEO as a minor fringe benefit.

Okay, reason number two might be to get some experience under our belt.  Practice, for the main event.


Give someone a sufficient [b][i]why[/i][/b] and they can endure just about any [b][i]how[/i][/b]

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#143 2005-04-15 11:05:47

SpaceNut
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Re: Post central for information on CEV III - Continued from previous

Man hour cost for refurbishment of engines does not come cheap and you must tear them completely appart to inspect for sea water caused damage inaddition to the normal process.

Now if it could seal tightly on the way down or be parachuted to a ground landing or even onto the deck of an air craft carrier then the refurb cost are much lower.

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#144 2005-04-15 12:13:27

GCNRevenger
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From: Earth
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Posts: 6,056

Re: Post central for information on CEV III - Continued from previous

"However, I have to disagree that making the engine pod recoverable would have been a significant cost increase"

I think you are flat wrong. You would have to develop what is basically a whole new space capsul... powerd, maneuverable, remote controlled, etc. in order to get those engines back down. You make it sound like that its a piece of cake, just a sunday-afternoon garage project, except with fancier materials... It is simply not that way.

More importantly though, is that there is no good reason for it. If the engine pod costs $1-2Bn to develop (reasonable considering a $5-6Bn CEV), which it very easily could, then you won't be saving much money versus the bigger and cheaper RS-68, and you'll have to pay to recover/refurbish the pod. Each SDV only needs $30-35M (2X) or $45-50M (3X) for the engines.

Also, going that route would preclude top-mounting the payload. This will doom SDV from ever carrying people (no MarsDirect. Period.), reduce the payload by 5-10MT (off-axis thrust), and precludes using a heavy upper stage (again, no Direct anything).

"I do have to emphasize the need to use at least 3 SSMEs and a fairing, don't use 2 SSMEs"

Absolutely, but RS-68 is preferrable.

"...with 2 OMS pods, each with an RCS thruster pod, you can rendezvous with ISS. Without the nose thruster pod you can't dock, but you can rendezvous and stabilize cargo."

With that size of a payload and no nose thrusters? And don't forget, you would also need heavy payload clamp adapters. You would need to make it much, much more maneuverable and "smart" then you would need for a non-rendevous payload delivery.


[i]"The power of accurate observation is often called cynicism by those that do not have it." - George Bernard Shaw[/i]

[i]The glass is at 50% of capacity[/i]

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#145 2005-04-16 16:16:19

John_Frazer
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From: Boulder, Co. USA
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Posts: 75
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Re: Post central for information on CEV III - Continued from previous

SpaceNut:
I agree with the clippngs you posted. The 2-SSME (or eq) version doesn't seem to hold much over the existing crop.
It's the bigger loads I'm thinking of. Using the throw-weight of that launch stack, not to throw 80 tons of reusable manned spaceplane plus a bit of cargo, but all cargo.

The version of Shuttle-Z they presented was unknown to me. I'd always associated the "Z" with top mounted cargo, and in-line engines underneath.
That loses the advantage of using the esisting design ET, and they both lose the adantage of the Shuttle-C:
GCNR wrote
>  I am beginning to think that there is a real irrational pathology going around that demands to find worth in the Shuttle program, perhaps as redemption for its failure in the face of being trumpeted as a national treasure, and willfully ignoring bad things about it.
and
> There is a big difference between SDV and EELV+ other than the economies of scale: the difference is that the whole construction, integration, and launching of SDV is inherintly inefficent because it relies on outdated technology and methods.

Philosophically I agree, but the Shuttle-C eliminates the Golden Goose orbiter, but here's the important bit it uses all the same vehicle handling and launch infrastructure we've got in place. No modifications to the launch pad or ET for the underneath in-line engines.
Yes, it smacks of feeding a horse which hasn't pulled its weight, to maintain the infrastructure just because it's politically expedient to use the congressional districts we've been using, and the personnel.
But it works. How long to develop a new SHLV and all the new infrastructure it needs and get it into use? twenty years or whenever they decide they're ready to return to the Moon or on to Mars?

Commodore
> Were going to spend a lot of money on the fancy aerodynamic shell and rockets of whatever we launch on a SDV.

Dream a nightmare for me, and try to find a way this could possibly cost as much as the orbiter. Go ahead. Just try. Especially since we're tossing aside the big dead-weight of the orbiter (making the cargo load between 4 and 5 times what it is now), along with the enormous cost of readying it for flight.

> Also, going that route would preclude top-mounting the payload. This will doom SDV from ever carrying people (no MarsDirect. Period.), reduce the payload by 5-10MT (off-axis thrust), and precludes using a heavy upper stage (again, no Direct anything).

The reason the Ares booster used off-axis thrust was to use the existing launch pads flame trenches, instead of having to spend more to build/rebuild new launch facilities.
I never liked launching the crew of a Mars Direct mission in their tuna can. That's even worse than the Shuttle: no possibility whatsoever, of any sort of bailout/escape (what, 4 encapsulated ejection seats?
Better to kludge the clean mission plan up by adding a flight of a CEV or equivalent and EOR. By flying a Mars Direct, we're asking enough of a crew, without demanding they do this. I don't know though... you might still get volunteers to ride it up.

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#146 2005-04-16 16:28:45

John_Frazer
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From: Boulder, Co. USA
Registered: 2002-05-29
Posts: 75
Website

Re: Post central for information on CEV III - Continued from previous

BWhite
> The ONLY reason for doing the Moon (beyond Bush said so) is to exploit lunar resources. Primarily PGM IMHO with lunar LOX exported to L1 and LEO as a minor fringe benefit.

Lunar resources are too far off to be of any consideration. Useless or worse for going to Mars, and inconsequential in its own right.
NEAs are where you want to go for space resources, or better yet for us. Mars' moons. No prospecting, just dig down, expose it in a solar furnace, and everything you want in a far far more advantageous position to use it for Martian exploration or anything else in space.

http://neofuel.com/]http://neofuel.com/
The Diemos Water Company
http://www.spacefuture.com/archive/the_ … pany.shtml

RobertDyck
> I think you'll find almost everyone here on this board supports going directly to Mars, not the Moon first. However, George W. said go to the Moon so NASA must go to the Moon.

The important thing is that George W's administration won't be doing anything, except the political grandstanding they did with their nonsensical "space plan".
They got their political benefit from the announcements, and ignored it from then on, and put off doing anything real until the 2009 administration. Even if Rummy or Condoleeza Rice gets into office, bets are that whatever we do in space won't bear much resemblence to W's supposed plan.

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#147 2005-04-16 16:54:37

oberth
Banned
From: Germany
Registered: 2004-11-28
Posts: 10

Re: Post central for information on CEV III - Continued from previous

They got their political benefit from the announcements, and ignored it from then on, and put off doing anything real until the 2009 administration.

They ignored it? That's news to me. What about Bush's veto threat when the FY 2005 budget was in trouble (no other president has ever done anything like that for NASA) or Tom DeLay's threat not to let the House vote on a any budget resolution that didn't include the $16.2 billion (a solid 5% increase over 2004) Bush requested? In the end NASA got the full increase. That would never have happended without the strong support from the White House and Republicans in Congress.
What about the selection of Michael Griffin as NASA administrator (A selection Zubrin himself has praised)?
What about the proposed increase in the NASA budget for 2006?

BTW: What "political benefit" did Bush get from the announcement? The plan was widely criticized by democrats and in the media. If anything it probably cost him votes.

Bush has done more for the space program than any other president since JFK. To say otherwise is just ignorant.

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#148 2005-04-16 17:50:17

GCNRevenger
Member
From: Earth
Registered: 2003-10-14
Posts: 6,056

Re: Post central for information on CEV III - Continued from previous

*Claps* Thank you Oberth, not enough people around here (of any political stripe) to illustrate Bush-bash nonsense.

Going back to the Moon makes perfect sense if you actually want to DO anything in space besides learn stuff and explore. Its just not true that Lunar reasources are a long ways off, because the things that are valuble on the Moon, Platinum and Helium-3, are not needed in vast quantities. A few kilos of Platinum metal would be enough for hundreds or perhaps thousands of car-sized fuel cells, and we all know how a little nuclear fuel goes a long, long way. In the likly event that a Platinum shortage looks to be a road-block to Hydrogen power, then getting it would be worthwhile... especially if we do start running out of oil. Using He3 in nuclear fusion reactors could also be worthwhile in the long-er term.

And the "but thats such a long time from now!" thing? Well, then if we need alot of it, best to start now with a beach-head, fuel depot, and mining technology testing ground. Once there is Lunar fuel available, NASA will be able to operate a minimal Lunar base, then Lunar operations will be much cheaper, and go we can then afford to go on to explore Mars.

There are two really really BIG things that the Moon has but Phobos/Deimos/NEAs don't:

1: Its close, you don't need a big mothership to put people on the Moon, a small capsule will do just fine.
2: Gravity, that the lack of gravity I think will be fatal to any near-zero-gee mining operation. The lack of gravity is a BAD thing.

...to maintain the infrastructure just because it's politically expedient to use the congressional districts we've been using, and the personnel. But it works. How long to develop a new SHLV and all the new infrastructure it needs and get it into use?"

You are missing my point, that you just casually gloss over the "maintains the personnel" like its a annoying mosquito bite or something. No! This is fatal to the idea, there are ten thousand people at least, perhaps a few thousands more, that are involved with STS operations. Unless this cost can be radically reduced, by 60-70% I figure, then SDV will be too expensive.

Right now STS costs a bit under $5Bn for 4-6 flights anually. NASA has, I figure, about $9-11Bn to spend on spaceflight, the rest going to various other projects. NASA just cannot afford to DO anything for $4-5Bn a year if the rest is sucked up by SDV.

If SDV can't be flown for $2.0-2.5Bn/yr for six flights at 100-120MT each - very preferably with crew - then its going to kill NASA. So you see, I don't think it matters how long it would take to build a new HLLV for Mars, if SDV can't fly for less then this amount, then it doesn't fly at all. Ever.


[i]"The power of accurate observation is often called cynicism by those that do not have it." - George Bernard Shaw[/i]

[i]The glass is at 50% of capacity[/i]

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#149 2005-04-16 18:18:30

oberth
Banned
From: Germany
Registered: 2004-11-28
Posts: 10

Re: Post central for information on CEV III - Continued from previous

I think we need an HLV (shuttle-derived or EELV-derived, whatever is cheaper both in development and operation) and Griffin has indicated he views this capability as critical.

I also hope NASA develops the lunar hardware with Mars missions in mind (again Griffin has indicated that's what he wants to do), so there won't be a huge gap between a return to the Moon and the first landing on Mars.

NASA should use the Moon primarily as a test-bed and then let the private sector gradually take over. Private companies could exploit the Moon's ressources or develop lunar solar power. For NASA to move on to Mars they will need an HLV so they should develop one now. It will make lunar exploration easier and it will make it virtually impossible to cancel the VSE.

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#150 2005-04-16 20:09:55

Ad Astra
Member
Registered: 2003-02-02
Posts: 584

Re: Post central for information on CEV III - Continued from previous

The sad fact is that nobody cares enough about space to let it influence their votes.  Just look at Keith Cowing of NASA Watch (an excellent site, IMHO.)  He stated flatly that he agrees with VSE and was very critical of John Kerry's vague space plans.  Nevertheless, he voted for Kerry anyway for a number of other reasons. 

Greg Zsidisn, a Kerry supporter, went so far as to compare his situation to that of von Braun, having to work on space development but only at the whims of the Nazis.  The conclusion he drew at the end of his extremist screed is that it's better to sacrifice our space dreams along with our 'mad furher' and to cross our fingers, hoping that the private sector will give us a decent space program.


Who needs Michael Griffin when you can have Peter Griffin?  Catch "Family Guy" Sunday nights on FOX.

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