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#26 2005-03-03 16:42:00

John Creighton
Member
From: Nova Scotia, Canada
Registered: 2001-09-04
Posts: 2,401
Website

Re: A new HLLV essay

I’m all for heavy lift but I don’t see why it has to be shuttle derived. As was previously stated there are options to increase the capacity of the delta IV heavy to 50-80 MT. As for clean sheet, I don’t think people mean completely new clean sheet. They mean taking the vest from the existing rocket lines to build a new rocket. Why should that take such a high development cost. Also if NASA goes with an upgraded delta IV heavy it doesn’t mean the instant demise of the solid rocket boosters. There will still be option for the delta IV heavy to use the solid rocket boosters to launch a greater MAS to LEO. The first causality will probably be the shuttles main engine. Given its cost and complexity why would this be such a tragedy. Don’t we have better engines today.


Dig into the [url=http://child-civilization.blogspot.com/2006/12/political-grab-bag.html]political grab bag[/url] at [url=http://child-civilization.blogspot.com/]Child Civilization[/url]

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#27 2005-03-03 17:38:51

publiusr
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From: Alabama
Registered: 2005-02-24
Posts: 682

Re: A new HLLV essay

There are certain shapes that just work. It is easy to bash that design--but due to having greater attachment points along the length and not just the diameter of the vehicle--side-mounting which reduces pitch-loads, etc.

The shuttle looks the way it does for a reason. If if Nixon had given SSTO all the money it needed, you would have had twice the wing weight, twice the landing gear--and no HLLV.

Energiya is a good shape.

Take a look at this mini/hybrid version of Energiya-Buran--er, Dream Chaser:

http://www.popsci.com/popsci/aviation/a … 53,00.html

Polyus:

http://www.militaryphotos.net/forums/vi … hp?t=30510

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#28 2005-03-03 21:46:23

robcwillis
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Registered: 2001-09-23
Posts: 71

Re: A new HLLV essay

GCN,

Re. your remarks:

" The actual machines used to make the RD-0120 have been converted to make other things, the production line no longer physically exsists."

and

"I find it reprihensable that you "lemming" yourself to whatever the Russians say."


1. Where do you get this stuff?

2. Do you judge the reliability of your source based on the national origin of the author, or is it just the representatives of Kosberg, Energomash, Molniya, and RKK Energia as opposed to all Russians who are liars?

You appear to imply that by definition, the more reliable source would be whomever is furthest removed from the the actual production line, so long as they are not of Russin ethnicity.

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#29 2005-03-03 22:43:13

RobertDyck
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From: Winnipeg, Canada
Registered: 2002-08-20
Posts: 7,813
Website

Re: A new HLLV essay

I used to work at a bus manufacturing plant (had trouble there, but saw the production line) and now work for a company that makes autopilots for miniature UAVs. I know what manufacturing entails. A serial production line like the bus manufacturer is for high production volume, it isn't necessary for low volume. At my current job we have equipment that sits on a shelf until it's used. I run the calibration system almost every day, but there were a couple weeks in which it didn't run because we worked on an upgrade. Some days the technicians work on radio modem base units, some days on radio modems for UAVs, other days on custom battery modules, or complete planes, or video units, or repairing autopilots that were returned for RMA. The tools are there, and often the same tools are used for different products. Just because the tools weren't used for a particular product recently doesn't mean they don't exist.

The Atlas V Heavy is a prime example. It's never been built, but the US Air Force says it's available on 30 months notice. That extreme lead time tells me they don't have all the tools or trained personnel necessary. To an extent it's vapourware. Energia was built and launched twice; it's more real than Atlas V Heavy.

But you'll also notice I don't say we "have to" use Energia. We could use Shuttle-C, but that configuration has the danger of retaining the full standing army of Shuttle technicians. Any space faring country could create a new clean sheet HLLV, but it would be very expensive. Energia is one option, and an option I don't want to loose. The greatest advantage of Energia is that it's the only HLLV that could be returned to flight.

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#30 2005-03-04 10:55:02

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

Re: A new HLLV essay

The other political reality is that if NASA is forced to use hardware because of political favoratism and not because it is the ideal situaiton, NASA is doomed to be stuck with another Shuttle-ish situation.

And how exactly do you intend to ensure that the Shuttle Army is largely culled, Publiusr? It seems to me that the temptation for NASA management or Congressmen to not cut down their number sufficently will be the end of everything. Shuttle costs $4.3Bn per year to operate, and under a quarter of that is actual flight hardware aproximatly. SDV would absolutely have to be operated for no more then half a billion per flight, which right now that seems pretty optimistic since the pieces alone would run ~$180M... only a bit more then Shuttle's consumeables, but it costs about $1,000M per flight. You mention it being a positive thing that we "keep jobs" or "keep the 747" but I say this is absolutely the wrost thing that could happen.

If Shuttle Derived is the only game in town, then there is a good risk that there aren't any games in town.

"Expect the worst. I find Zubrin more truthful than the EELV hacks myself."

Even when Zubrin states things that are factually not true? Not even an unlikly or an opinion, but wholey on/off, 1/0, yes/no untrue?

"A side-mounted orbiter scale hypersonic boilerplate in place of a possible future Buran type orbiter will keep the 747 in air as a hypersonic test-bed release ferry..."

"This won't be done all at once, but it allows HLLVs to have more payloads and most importantly--gives the hypersonics people a reason to support HLLV over an EELV that--outside X-37--won't help them a jot."

What? You do know that the "hypesonics people" by and large don't exsist right? They have no budget, no mission, and no future at the moment. They are definatly not a reason to build an inferior vehicle. And it would be inferior, you trade quite a bit of performance for side-mounting since you have to burn fuel to keep your rocket from tipping over on the way up... Ares, Magnum, Energia Vulcain, Delta, and Atlas all use top-mounting as it is the most efficent placement. Less drag too.

"Side mount allows outsized objects to be taken to space--and X-33 was to evolved into external payload pods due to all its internal volume going to fuel."

Actually no. This is because the X-33 was not going to be the ultimate end of the design, but rather a light spaceplane as a design test bed and for specialty payload (or weapon) delivery for the USAF. The Venturestar would have had a fully internal payload bay, made possible with its lower mass per volume.

The X-33 project cost a little over one billion, not "billions."

"Large scale hypersonic boilerplates will be released from the side of an HLLV/ET to undergo re-entry tests  AT LARGE SCALE--so as to have room for active cooling technology that cannot be done with surfboard sized X-43s"

Are you completly out of your MIND? ACTIVE cooling for reentry? Oh lord, I am going to rub my temples and pretend you didn't just say that. I think thats the dumbest idea i've heard since Errorist was building piplines.

"I still favor hypergolics for moonships"

Um, what? Why on Earth would we use low-performance, difficult to store, and somewhat unstable hypergolics? The huge performance difference between hypergolics and cryogenics for upper stage or TLI burns is absolutely critical, even with HLLV. Saturn with a hypergolic engine instead of the J-2 would never have made it to the Moon.

"Push for HLLV--and you MAKE the need."

Um, no you don't, and I find your "doomsday senario" and discounting of the capability of capsules as rediculous... And frankly, I don't exactly put much stock in the Starlifter people, nor this fellow at TheSpaceReview who can't add... The cost of the parts alone for Ares would aproximatly equal his estimate, and not include money for all the engineers to ready and fly it. Same deal with Shuttle-C with SSMEs.


[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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#31 2005-03-04 15:23:33

publiusr
Banned
From: Alabama
Registered: 2005-02-24
Posts: 682

Re: A new HLLV essay

"And how exactly do you intend to ensure that the Shuttle Army is largely culled, Publiusr? It seems to me that the temptation for NASA management or Congressmen to not cut down their number sufficently will be the end of everything. Shuttle costs $4.3Bn per year to operate, and under a quarter of that is actual flight hardware aproximatly. SDV would absolutely have to be operated for no more then half a billion per flight, which right now that seems pretty optimistic since the pieces alone would run ~$180M... only a bit more then Shuttle's consumeables, but it costs about $1,000M per flight."

Even if that is true, that still comes to $200 million per 20 tons--the same or less than EELV, and with far less RS-68s and upper stages expended. And less construction time.

The actual cost is still less.

"Even when Zubrin states things that are factually not true? "

And how is what he says on this not true?

"Side mount allows outsized objects to be taken to space--and X-33 was to evolved into external payload pods due to all its internal volume going to fuel."

"Actually no. This is because the X-33 was not going to be the ultimate end of the design, but rather a light spaceplane as a design test bed and for specialty payload (or weapon) delivery for the USAF. The Venturestar would have had a fully internal payload bay, made possible with its lower mass per volume."

Not according to the book Lockheed's Secret Projects. The payload was in fact to be exterior/side-mount for Venture Star.   Look it up.

"Are you completly out of your MIND? ACTIVE cooling for reentry? Oh lord, I am going to rub my temples and pretend you didn't just say that. I think thats the dumbest idea i've heard since Errorist was building piplines."

You are not listening. Side mount allows for scramjet boilerplates and allows for active cooling to at least be tested in large scale. If that doesn't work--you can go to a Faget Straight wing. That is why engines need to go under the ET, so you are not limited to any one wing design--any one orbiter. I have seen drawings of side mount aerobrake disks wider than an orbiter's wingspan for some of Boeing's old Shuttle-C proposals. Top mount will not allow for this.


"Um, what? Why on Earth would we use low-performance, difficult to store,"

They are called storable propellants because they are in fact more easily stored. That's the dumbest statement I've heard you make in some time.

"And frankly, I don't exactly put much stock in the Starlifter people, nor this fellow at TheSpaceReview who can't add... The cost of the parts alone for Ares would aproximatly equal his estimate, and not include money for all the engineers to ready and fly it. Same deal with Shuttle-C with SSMEs."

So you say sir; But I don't put much stock in your opinions, because you can't subtract.

I want only three SSME's/RS-68s per 100 tons.

You want 15 thrown away in five launches of that pad-sitting Delta IV with piecemeal ISS assembly.

That means you want to throw away 12 more engines than are needed, not counting five upper stages, pad time, etc.

Now who can't do math?

It's shuttle-derived or nothing pal.

Deal with it.

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#32 2005-03-04 17:16:24

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

Re: A new HLLV essay

EELV can put up 40MT-50MT for ~$200M, while I estimate the cost for Shuttle-C to be $185M just for the nonelectronic parts alone (mod. ET, 2X SRB, 3X RS-68 lower/1X upper). Best case senario, Shuttle-C will be only marginally cheaper, and will be less flexible due to not having a "light" configuration.

"And how is what he says on this not true?"

Bob Zubrin claims in that PDF you linked that all componets, CEV/Lander/2X TLI would all have to be launched in a short window and that this was not practical. This is simply not true, since the lander can be sent ahead of time to LMO before the CEV needs to be sent, and a cryogenic TLI stage should be able to hold its fuel for at least a month before it would experience excessive boiloff. What Doc Zubrin claims is simply, obviously not the case, and he is not stupid... so he must be lying.

"Not according to the book Lockheed's Secret Projects. The payload was in fact to be exterior/side-mount for Venture Star.   Look it up."

Ah huh, "secret projects." It is a simple matter of math that when volume increases, surface area doesn't increase as much, hence mass does not increase as much. Hence, the larger Venturestar would have been light enough not to need so much fuel that it would eliminate an internal cargo bay. The USAF wanted the X-33 to be their "SMV" vehicle and would therefore need to carry at least a little payload... so it would be logical to bolt it onto the side, since the X-33 was not designed with a cargo bay since it was only a technology demonstrator.

"active cooling for reentry"

You specifically stated it was for reentry, which means active cooling to deal with heating caused by reentry... which is a competly stupid concept given how dangerous it would be and inefficent since you would have to carry coolant. It is an inherintly bad idea...If you mean to test regenerative scramjets, that is a whole different matter entirely. In such a case, you wouldn't build a giant side-mount rocket now just for testing an engine we won't need for 30-40 years.

If you mean for a TSTO "conventional" spaceplane, we will be building a hypersonic carrier plane anyway, and also won't need any huge rocket.

"so you are not limited to any one wing design--any one orbiter. I have seen drawings of side mount aerobrake disks wider than an orbiter's wingspan... Top mount will not allow for this."

We don't need any orbiter spaceplane at all again ever for HLLV, the whole idea of wasting a huge rocket to lift an 70-80MT spaceplane just so you can get 30MT to orbit or a single crew rotation is an inherintly bad deal. No Shuttle V2.0!

As far as aerobrake shield size, NASA already has that taken care of in their DRM mission plan. The biconic aeroshell ("bullet") shape is less wide then a big disk/sphere type shell, but it will work too. It can even double as the payload faring.

And I suppose the aerodynamic issues won't be a problem for Shuttle-C with a huge disk/wing on the side either?

"They are called storable propellants because they are in fact more easily stored"

Relativly easier to store, compared to LH2 or LOX or LMe, they're a cinch... for a while. Large tanks, like those on Soyuz, can only be trusted with them for ~6mo before the extreme corrosive effects of Dinitrogen Tetraoxide or the inherint instability of Dimethyl Hydrazine becomes a concern.

They are NOT suitable for long-term storage on any scale, and their low performance is a serious liability. At least with cryogenics, you can recondense the boiloff.

Why do you continue to pig-headed and stupidly ignore when I say that EELV can be upgraded? It can, the Delta-IV could be made from Lithium alloy like STS-ET, the RS-68 can have a higher Isp with a regenerative loop, and so on... SIX RS-68R engines for 80-100MT, not "fifteen."

Maybe you inhaled some of the nasty Hydrazine and it has ruined your reading comprihension and math skills... SDV is simply not the only option.


[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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#33 2005-03-04 20:53:40

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

Re: A new HLLV essay

I have reservations about a regenerative "RS-68R."  The RS-68, while heavier than the SSME, can get away with a lower parts count because it uses an ablative nozzle instead of a regeneratively-cooled one.  This is consistent with the "big dumb booster" philosophy of sacrificing performance and taking on more weight in exchange for simplicity and lower cost.

A regeneratively-cooled RS-68 would be a very different animal than the original RS-68.  It would have about 2x the parts and would probably be more expensive by a similar factor.  If you plan on building a lot of these engines and throwing them away on expendable rokets, I would rather go with the lower performance and find a way to lighten my payload instead.


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

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#34 2005-03-04 21:01:56

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

Re: A new HLLV essay

That is mainly because of the complex cooling liquid hydrogen tubes, their fixtures, the welding, and so on. If the "R" model were built like the RD-0120, which used a novel one-piece "jacket" for the nozzle, this should not be an issue.

Even if it were double the complexity, it would still only be half as bad as SSME and add only ~$20-30M to each SLHV... it would also add to the cost of Shuttle-C by a similar amount, since they assume the higher Isp offerd by the "R" model.


[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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#35 2005-03-10 17:43:23

publiusr
Banned
From: Alabama
Registered: 2005-02-24
Posts: 682

Re: A new HLLV essay

"Ah huh, "secret projects." It is a simple matter of math that when volume increases, surface area doesn't increase as much, hence mass does not increase as much. Hence, the larger Venturestar would have been light enough not to need so much fuel that it would eliminate an internal cargo bay. The USAF wanted the X-33 to be their "SMV" vehicle and would therefore need to carry at least a little payload... so it would be logical to bolt it onto the side, since the X-33 was not designed with a cargo bay since it was only a technology demonstrator."

Nice try. But it doesn't work that way--because, unlike a parasite orbiter all the tankage needs heavy heat-sheild--so the small increase in surefacer area still hurts you--thus:

http://www.space.com/missionlaunches/la … ...22.html

At least others are talking heavy lift:

http://www.spacedaily.com/news/rocketsc … e-05i.html
http://www.thespacereview.com/article/3 … icle/335/1


"Why do you continue to pig-headed and stupidly ignore when I say that EELV can be upgraded? It can, the Delta-IV could be made from Lithium alloy like STS-ET, the RS-68 can have a higher Isp with a regenerative loop, and so on...Maybe you inhaled some of the nasty Hydrazine and it has ruined your reading comprihension and math skills... SDV is simply not the only option." Mr. G doesn't feel that way

http://www.space.com/spacenews/business … 40412.html

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#36 2005-03-10 18:30:14

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

Re: A new HLLV essay

Mister Griffin is correct, that the EELV aproach most likly would most likly not be as efficent as SDV or Clean Sheet heavy lifters, and I am not arguing that. The EELV aproach isn't really competitive in this way...

...what I am saying, however, is that:
1) There is a good chance SDV launch costs could bankrupt NASA due to massive manpower requirements
2) EELV+ costs are basically a known quantity, as vehicles similar to the ones needed are flight tested
3) As nice as clean sheet would be, its not happening right now if NASA intends to get to the Moon on time

Given the above, I can't support SDV until there are credible estimates for its cost. This being the case, EELV will be the best option. We will need to use an upgraded EELV anyway to launch the crew on, unless you intend to put people on top of the SDV.


[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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#37 2005-03-10 20:45:28

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

Re: A new HLLV essay

GCNRevenger is right in that we should wait to see the cost estimates before we start taking sides.  Can SDV be flown for a significantly lower amount than STS?  Will we get economies of scale by making multiple EELV flights?  It's hard to say, because we have neither flown an SDV nor pushed the EELV's to their limit (although Boeing and LockMart think they can launch 18 missions per year or so.)

I don't think there's any way of getting around an EELV launch for the CEV.  NASA wants a capsule that can blow free of its booster during a launch abort.  You could either stick the capsule atop an EELV (or SRB-derived rocket,) or modify the shuttle ET extensively into an in-line launcher (which would be an entirely different animal from the Shuttle-C.)

NASA's modus operandi is safety.  The capsule + escape tower setup has a proven record of success (it saved two Soyuz crews.)  Yes, it subjects astronauts to high g's, but it's for a tolerably short amount of time.  An ejection seat does the same thing. 

A side-mount ship, on the other hand, would need to eject perpendicular to the flight path.  Clearing the fireball from the booster would be very difficult, perhaps impossible, with current technology.  NASA estimates showed that the ejection seats used during STS-1 thru STS-4 would have been incinerated in the plumes from the SRB's.  The chances of successful escape would be even lower if the booster exploded like Challenger.  The ejection system (whether seats or escape pod) would only be useful in horizontal flight.


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

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#38 2005-03-10 21:16:30

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

Re: A new HLLV essay

The EELV's don't have to have larger economies of scale, they are minimally affordable right now. We would not need an insane number of flights either, about twelve to fifteen per year for three Lunar missions annually, which should not be difficult or fatally expensive to do if CEV weighs only 20MT with TEI stage.

It is a known and capable option, and is the only option that we know with confidance is affordable and capable.

I am not real fond of the idea of putting crews on any model of the SDV or any rocket with large solid rocket boosters, due to the nasty things that would happen if one failed. Can't shut them off, too big to eject, and little warning of failure.

Since SDV will likly use SRBs, and would have a large number of engines anyway, I think that will lead to putting too much faith in the robustness of the escape system and the crash surviveability of the capsule.

Good point about emergency seperation from side-mounting being impractical... that pretty much seals the fate of Shuttle-C being used for direct flight to anywhere. Most of NASA's SDV concepts are top mount anyway it would seem.


[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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#39 2005-03-10 22:06:06

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

Re: A new HLLV essay

I don't like solids of any size for manned space flights.  Even the small solids, like those on the Delta II, are a significant Achillies' Heel.  Bear in mind that the last Delta II failure was due to an SRM problem.

For the manned CEV launcher, liquid-only versions of the Atlas V and Delta IV are the only choices.  A "heavy" version of the EELV will be expensive, but the safety advantage over solids is appreciable.  If Boeing and LockMart can switch to Al-Li tanks and fly a lighter single-core EELV that's capable of launching the CEV, that would be even better.  It would probably be cheaper than the Heavy EELV's, and would have 1/3 the chance of a first-stage engine failure.

If the rumors are true about a "down-select" for the EELV, I would say that the victim of the down-select should switch their production line to the uprated model that can launch the manned CEV.  That way you're not tasking one company to have two different production lines.


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

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#40 2005-03-10 22:56:47

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

Re: A new HLLV essay

I am inclined to agree that solid fuel engines should be avoided for manned flights, but I'm skeptical that any single-core varient of the EELVs could hit the 20MT mark that CEV requires without SRMs. Atlas-V might be able to pull it off with signifigant modifications, but thats iffy. Delta-IV almost certainly can't, not 20MT.

If the whole CEV, capsule and TEI fuel, is to be packed into that 20MT figure then it only makes sense to fly it as a unit and not seperatly, so that you would have the ability to abort to Earth at any time. Flying CEV on the tripple-barrel version will cause problems with how many EELV cores can be produced yearly. If you can launch the CEV and its TLI stage on two single-barrel shots and the lander with two tripple-barrel shots, that saves you four whole cores per expedition, which adds up fast.

Otherwise, you will have to split up the capsule and TEI engine, adding an additional staging event to the CEV and requiring redundant OMS systems. Small solid rockets might not be avoidable.


[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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#41 2005-03-11 06:13:12

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

Re: A new HLLV essay

Boeing designed its Decatur, AL factory to produce 40 CBC's a year.  That should be plenty if they plan on fifteen launches per year, even if most of those launches are the heavy variant.


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

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#42 2005-03-11 07:04:19

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

Re: A new HLLV essay

Fifteen HLV flights per year would require 45 booster cores, and using the single-barrel boosters versus the heavies would save ~$400-500M a year. (6X $120M vs $190M)

I thought that they could produce only 20 per year? If it is the lower number, then flying CEV on a single-core vehicle is probobly very important if a perminant base is built with regular rotations.

How much safety is really being gained by flying a pair of big booster cores versus a pair of small solid rockets?


[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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#43 2005-03-11 10:47:38

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

Re: A new HLLV essay

Mister Griffin is correct, that the EELV aproach most likly would most likly not be as efficent as SDV or Clean Sheet heavy lifters, and I am not arguing that. The EELV aproach isn't really competitive in this way...

...what I am saying, however, is that:
1) There is a good chance SDV launch costs could bankrupt NASA due to massive manpower requirements
2) EELV+ costs are basically a known quantity, as vehicles similar to the ones needed are flight tested
3) As nice as clean sheet would be, its not happening right now if NASA intends to get to the Moon on time

Given the above, I can't support SDV until there are credible estimates for its cost. This being the case, EELV will be the best option. We will need to use an upgraded EELV anyway to launch the crew on, unless you intend to put people on top of the SDV.

It strikes me that the VSE is falling "in between" EELV and SDV in terms of whether we "need" 100MT boosters. EELV is just too small to support permanent presence on the Moon and SDV may be just too big (& expensive) to fit NASA's budget and there does not appear to be a "just right" solution.

EELV may be better if the medium term goal (15-25 years) is to go slowly and postpone permanent presence for several decades while SDV may be necessary if the 15-25 year goal is to achieve and maintain a substantial presence on the Moon.

And, if Mars is to be anything more than "after the Moon, whenever. . ." EELV will plainly be insufficient.

= = =

Heh!

It always comes back to "why" we are going. At least IMHO.



Edited By BWhite on 1110563332


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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#44 2005-03-11 11:48:45

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

Re: A new HLLV essay

Its all a matter of the actual crew vehicle's specifications really... You can build the capsule one of two ways:

1) Build it with only minimum propulsion/supplies for LEO use, and dock it to an Earth-Return stage later. In this case, the CEV would definatly be light enough for no-SRM launch, but it would decrease overall efficency by needing two OMS engines, two sets of OMS/LSS tankage, etc as all this hardware would be duplicated on the Earth-Return stage.

2) Build CEV with enough propulsion/supplies for TEI on the standard model CEV. This skips needing the extra half-dozen tonnes of total launch mass for LEO-only operation, but makes CEV heavy enough that it can't ride on Delta-IV Medium and maybe not ride on Atlas-V "Medium" withoud SRMs.

Putting the crew capsule on top of an axial-mount SDV is probobly possible, but I think that it is undesireable. Man-rating smaller rockets is easier then man-rating bigger ones, and this way you can pack extra mass that CEV would have taken on it or get away with lower-performance engines/materials to save hardware costs. Not to mention slim down the Shuttle Army some more since it no longer has to "never ever fail."

About Mars, I think that it is safe to say that it is so long into the future that clean-sheet would be a practical option, and the cost of developing a small (80MT) one would not be outrageous. The decision for the Moon should be based soley on what is the  best option for the Moon.


[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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#45 2005-03-11 11:51:00

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

Re: A new HLLV essay

As for Moon only architecture, I believe starting with a re-useable lander that can be based at an L1 station will best support permanent presence.

An FGB-2 equivalent plus Bigelow inflatable plus docking ports and solar panels is all we need for an L1 outpost and then CEV need only be capable of reaching L1.

= = =

Edit: Lunar LOX is easy to extract and "should be" part of the architecture from the very beginning. Lunar water is unproven, difficult to extract and requires massive power to crack into H2. Postpone that until later.

If we carry LH2 or methane and use lunar oxygen from the very beginning, launch mass can be limited to a degree.



Edited By BWhite on 1110563623


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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#46 2005-03-11 12:01:42

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

Re: A new HLLV essay

No, no no no, absolutely not!

Use only expendable landers, period, until fuel is either launched by RLV from Earth or extracted from Lunar soil. No exception. A reuseable lander is a terribly inefficent system unless you have basically "free" fuel from Earth or "free" fuel from the Moon in quantity, which is a ways off. Expendable landers are obviously preferable before such a time, especially with our tight mass constraints. Throwing away an expensive RLV for every single sortie until we have fuel available will be a terrible waste.

And no manned space station! Absolutely not, not now and not ever. It will not "best support" anything, if you need a base to operate from that is nearby, we have this little blue planet a handy three days away called "Earth."

FGB-II is not ever going to happen, there is no way that America is going to send them a dime that they don't have to, and there is no way VSE can sustain the cost of building an American space station. And until Bigelow can demonstrate that his HAB module works, he should not be trusted at all.

FGB-II is a terrible place to start from anyway, no provision for a fuel storage platform, not enough solar power for a fuel condenser, and no where near enough radiation shielding being above the Van Allen belts. If you need to do crew or fuel transfers, don't bother rendevousing it at L1, just do it directly in LEO/LLO.

Edit: If we are going to be setting up a base, then sending all the equipment (high-temp nuclear reactor for metal oxide cracking, chemical plant to actually extract and liquify LOX and store bulk LH2/LMe, digging equipment to handle the regolith and metal slag, HAB complex, CLSS plant, and perhaps green houses) then we are going to need alot of flights before we can make rocket fuel, too many to spend a reuseable lander on each flight.

Reason being, that launching the entire RLV into LLO instead of just a little acent stage will require loads more fuel brought from Earth, and VSE's arcitecture has to be kept light.


[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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#47 2005-03-11 13:15:59

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

Re: A new HLLV essay

*Mulls* ...Maybe I was too hastey...

When I hear "reuseable" I am automatically biased to thinking that it must by nessesity weigh lots more then non-reuseable. This is more true for Earth vehicles then Lunar ones, and more true for ones made with old materials then newer ones. If you were to eject the spent decent fuel tanks and non-acent payload on the Lunar surface before acent, that would make a big difference.

You would have to then install fresh loaded fuel tanks from Earth though, and have to lug them along, partially defeating the mass advantage of a reuseable vehicle to begin with.

Building the lander in such a fasion that it could dump, say, an inflatable HAB module might be difficult however, and I question that a reuseable lander would really be so much cheaper then an expendable one since you'll be flying a new HAB, new surface payload, new fuel tanks, and so on anyway.

And if you want to send heavier payloads, then an expendable is probobly going to come in handy.

My position on no manned Lunar space station stands though.


[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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#48 2005-03-11 13:30:13

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

Re: A new HLLV essay

Lunar LOX? Absolutely essential!

However, shovel regolith into a closed chamber and heat with a passive solar furnace and O2 is extracted. Pyrolysis is simple and requires little expensive or massive equipment. Who cares if it is inefficient from a chemists point of view. Its darn cheap from an accountant's point of view.

Use parabolic inflatable/gossamer mylar mirrors plus pumps and compressors. A few hundred thousand dollars worth of equipment. Maybe a million or two, at most.

Lunar H2 or methane?

There just won't be any without massive infrastructure. Massive infrastructure cannot be built without large amounts of mass sent from Earth. As like Taylor Dinerman wrote, sending giant Catepillar trenchers and bulldozers may well need an HLLV.

So, we need to find a way to ship methane or LH2 to L1 (or LEO?) cheaply and efficiently. An HLLV could throw a decent supply of methane to L1 in a single throw. Add a rigid superstructure of trusses around your hab and use the methane tanks as a rad shield.

Suppose we assigned a Proton or a 5 segment SRB + RL-60 upper stage to deliver methane to L1. What would be the net price per pound?

Whatever that price is, how will you ever extract lunar LH2 or LMe for less than that price, without a truly massive upfront infrastructure investment?

Factoring in upfront costs of capital, extracting lunar LOX and bringing methane from Earth will be the most efficient route for a long time to come.

= OR =

We can declare that space exploration is essentially ON HOLD until we deploy honest-to-God RLVs. Except for a handful of flags and footprints stunts allowing us to pretend we are exploring space.

Because going to the Moon with EELVs using architecture we know is too flimsy to accomplish anything permanent is merely an Emperor's New Clothes type of undertaking.

AND - - as of today, no one is funding the R&D needed to build honest-to-God RLVs.


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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#49 2005-03-11 13:35:17

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

Re: A new HLLV essay

My position on no manned Lunar space station stands though.

Okay, design the L1 Gateway to be capable of periods of vacancy. Is that possible?

Its more of a transfer station designed to be as remotely self-sufficient as possible. The goal is to find a place to park lunar landers when not in use.

= = =

But again, it all depends on how full we intend the schedule to be.

One lunar mission in 2019, another in 2022 and #3 in 2027?

Yup. I then agree with you, L1 and re-useable landers would be a waste of money. And also, our being space advocates would be a waste of time. tongue


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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#50 2005-03-11 13:45:59

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

Re: A new HLLV essay

"WHY?"  matters to a very great degree here.


If 6 lunar missions between 2020 and 2035 fulfill the "vision" of the VSE then an L1 station is not necessary and is an un-needed expense.

But if we only use expendable landers then we are no closer to a substantial and sustained presence.

Even if we have fancy viewgraphs for what we will do in 2040 or 2050.

(Add: This should drive the EELV & HLLV decision. If we want a less expensive skimpy program, okay go EELV, but understand what we are buying may not be what enthuses the public, who elect the politicians, who write the checks.)

= = =

With a depot at L1 with stockpiles of lunar LOX and Terran methane, re-useable landers can land anywhere on the Moon at any time. As often as crew can fly from Earth to L1.



Edited By BWhite on 1110570642


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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