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#26 2005-06-07 06:57:23

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

Re: Shuttle derived revival - Space.com

[color=#000000:post_uid0]Ummm, I don't think that Greg was making a statement, he was just distilling down -our- arguments about Griffin and SDV.

Anyway... I don't buy your statement that Griffin is supposed to report to Rumsfeld clark, that sounds mighty fishy to me, where did you get this idea?

That said however, if NASA and the USAF can both buy the same rocket, that would go a looong way to fixing one of the cheif problems of modern spaceflight, that flight rates are too low to take advantage of economies of scale.

SDV is not worthless, if it could be pulled off it would work well enough to send heavy payloads and manned Lunar vehicles (until Lunar fuel or an RLV is available anyway) and could lift enough payload for a NASA-DRM style Mars program (too small for MarsDirect however w/o nuke rockets). It wouldn't be good for much else (SDV would [u:post_uid0][b:post_uid0]not[/b:post_uid0][/u:post_uid0] be practical for ISS construction) however.

Robert, you are enumerating ways to treat symptoms, but not the disease... [i:post_uid0]Obviously[/i:post_uid0] NASA should do these things, no competant managerial staff trying to get things done would permit this behavior. Therefore, the explanation is simple, that they [i:post_uid0]are trying to get [u:post_uid0]nothing[/u:post_uid0] done[/i:post_uid0]. The buracracy surrounding Shuttle isn't this wildly, vastly inefficent incidentally, its [i:post_uid0][u:post_uid0]intentional[/u:post_uid0][/i:post_uid0]. If engineers only get to work 1/4th the day instead of 3/4ths, then you need (or "get to") employ many many more engineers. Same with vehicle upgrades, so long as the vehicle is never "good enough," then they will be employed perpetually... I think this is one of the objectives of the original founders of the Shuttle program, that they -knew- their vehicle would not be good enough, so that they could retain hundreds or thousands of engineers.

I trust you are seeing a pattern here... This is what Griffin must destroy if NASA is to survive, one way or another, he has no choice. His enthusiasm for SDV and apathy to the EELV option illustrates that he very likly does not have the strength of will to do what must be done.

Griffin has even spoken of getting Michoud (which makes big foam-coverd aluminum gas tanks that have blown up the vehicle they're attached to... [i:post_uid0]twice[/i:post_uid0]) to build the CEV (the small, highly complex space capsule that hasn't been done in a generation) during the "STS-SDV gap".[/color:post_uid0]


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

The glass is at 50% of capacity

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#27 2005-06-07 07:26:54

clark
Member
Registered: 2001-09-20
Posts: 6,253

Re: Shuttle derived revival - Space.com

[color=#000000:post_uid0]

Anyway... I don't buy your statement that Griffin is supposed to report to Rumsfeld clark, that sounds mighty fishy to me, where did you get this idea?
[/quote:post_uid0]

Like everything else, I make it up.  tongue  big_smile

http://www.ostp.gov/html/SpaceTransFactSheetJan2005.pdf

Relevant portions are on pages 3-6.[/color:post_uid0]

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#28 2005-06-07 08:15:50

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

Re: Shuttle derived revival - Space.com

[color=#000000:post_uid0]

CEV is a top priority and I see no reason why it will, or should, be curtailed to make way for SDV development. [/quote:post_uid0]

CEV has yet to be defined. Its mission remains ambiguous.

What exactly is the objective of the VSE, anyway?

WHY should CEV be a top priority?

= = =

Griffin leads NASA, but Griffin serves at the pleasure of the President and is primarily charged with executing the President’s directives. I’m sorry, that’s just how it works over here.[/quote:post_uid0]

NASA's objectives SHOULD be set by Congress.

And I reserve my right to whine and complain at anyone who says "Bush said, therefore it shall be so."

big_smile

"Dr. Bush" to quote Robert Zubrin.[/color:post_uid0]

Edited By BWhite on 1118153986


Give someone a sufficient why and they can endure just about any how

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#29 2005-06-07 08:27:11

clark
Member
Registered: 2001-09-20
Posts: 6,253

Re: Shuttle derived revival - Space.com

[color=#000000:post_uid0]

CEV has yet to be defined. Its mission remains ambiguous.

What exactly is the objective of the VSE, anyway?
[/quote:post_uid0]

LOL!

Colonization Bill. At least for you. Pushing the edges of our scientific understanding for others. A platform for the development of practical applications for yet some others. A social policy to attract and increase the number of engineers and scientists in society for others. A big waste of time and money for some other folks.

It is everything and nothing, it is whatever we want it to be. For me, it is simply the first step in increasing our choices and opportunities for the future of space exploration.

WHY should CEV be a top priority?[/quote:post_uid0]

Because the Shuttle is doomed, ISS a dead end (from it’s stated genesis), and we desperately need to do something different if we want to go further with manned exploration.

NASA's objectives SHOULD be set by Congress.[/quote:post_uid0]

Yeah, well, the if the world were run by “should”, it would be a lot different. Besides, Congress did set the objectives- by signing onto Bush’s vision. Moot point.

And another thing, Congress is a big committee, and we all know about designs made by committee. :laugh:

And I reserve my right to whine and complain at anyoine who says "Bush said, therefore it shall be so."
[/quote:post_uid0]

That and 2.50 will buy you a cup of coffee. big_smile[/color:post_uid0]

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#30 2005-06-07 09:14:07

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

Re: Shuttle derived revival - Space.com

[color=#000000:post_uid0]

CEV has yet to be defined. Its mission remains ambiguous.

What exactly is the objective of the VSE, anyway?
[/quote:post_uid0]

LOL!

Colonization Bill. At least for you. Pushing the edges of our scientific understanding for others. A platform for the development of practical applications for yet some others. A social policy to attract and increase the number of engineers and scientists in society for others. A big waste of time and money for some other folks.

It is everything and nothing, it is whatever we want it to be. For me, it is simply the first step in increasing our choices and opportunities for the future of space exploration.[/color:post_uid0][/quote:post_uid0]
[color=#000000:post_uid0]And what we will get is the "Emperor's new space program" with NASA buying EELV for the same reason the Air Force leases refueling tankers.   tongue

Finding a profitable business model is the only objective that matters. Otherwise nothing is sustainable.[/color:post_uid0]


Give someone a sufficient why and they can endure just about any how

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#31 2005-06-07 09:17:03

clark
Member
Registered: 2001-09-20
Posts: 6,253

Re: Shuttle derived revival - Space.com

[color=#000000:post_uid0]

And what we will get is the "Emperor's new space program" with NASA buying EELV for the same reason the Air Force leases refueling tankers.   
[/quote:post_uid0]

Sorry, not cynical today, took my orange pill.  tongue

Finding a profitable business model is the only objective that matters. [/quote:post_uid0]

Spoken like the consumate yankee you are.  big_smile

Otherwise nothing is sustainable.[/quote:post_uid0]

This conversation proves otherwise.  :laugh:[/color:post_uid0]

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#32 2005-06-07 09:29:36

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

Re: Shuttle derived revival - Space.com

[color=#000000:post_uid0]Drink more Gatorade

“I wanna be/ I wanna be/ I wanna be … like Mike…”[/quote:post_uid0]

= = =

Actually, that would make a pretty funny spoof.

Morph together some film clips of Mike Griffin with Michael Jordan's Gatorade jingle, "I wanna be like Mike"[/color:post_uid0]


Give someone a sufficient why and they can endure just about any how

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#33 2005-06-07 09:47:44

SpaceNut
Administrator
From: New Hampshire
Registered: 2004-07-22
Posts: 17,825

Re: Shuttle derived revival - Space.com

[color=#000000:post_uid0]Back to why costs are not lower if Nasa and USAF can both buy the same rocket. Well actually they can but how many do the USAF buy is what set the price so high for the Nasa purchasing of the same rocket. Not many..[/color:post_uid0]

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#34 2005-06-07 11:03:01

clark
Member
Registered: 2001-09-20
Posts: 6,253

Re: Shuttle derived revival - Space.com

[color=#000000:post_uid0]More nails in the coffin?  big_smile

Very well...

The whole issue of price breaks for both NASA and USAF is largely irrelevant. Like it or not, some military and policy wonks have shaped national security policy to require that the US of A have two families of launch vehicles, better known as EELV, at all times, in order to provide responsive and flexible launch on demand for military needs.

The way the scheme was supposed to work was that EELV would eventually bring better performance while also reducing price. The price break has yet to be achieved. In fact, the cost of EELV is getting so high that some in Congress and the military want to down select to just one launch family.

That presents a problem because if there is ever some massive failure with the single launch family, nothing gets flown. Not exactly the ideal situation when you are contemplating a policy of assured access and denial of space. Also, those who champion the 2 family launch vehicle strategy see the problems with trying to keep both birds flying- the cost. Again, due to budgetary constraints, USAF needs relief in supporting the EELV program.

USAF is about to embark on a huge capital outlay for new fighters. Couple this cost with having to replace many of the aging sats in space, and build the new ones (like the gloriously over-budget SBIR) and it becomes difficult to manage everything at once.

By having NASA purchase EELV, USAF can free up some funds for hardware acquisition, while also assuring that neither EELV rocket family falls to the wayside. With SDV, you will not hit the demand level necessary to keep both EELV rockets afloat.

That’s why if you read the space policy PDF I linked to, you will see that over-arching authority for this decision is made in light of military and national needs, with civilian/exploration requirements coming a distant second. Rumsfeld will view all of the information within the context of military needs, and given that SDV does little to improve national security or help with national policy goals (such as keeping US aerospace afloat), Bush will choose EELV.[/color:post_uid0]

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#35 2005-06-07 11:07:40

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

Re: Shuttle derived revival - Space.com

[color=#000000:post_uid0]

Back to why costs are not lower if Nasa and USAF can both buy the same rocket. Well actually they can but how many do the USAF buy is what set the price so high for the Nasa purchasing of the same rocket. Not many..[/quote:post_uid0]
First let's ask whether the same vehicle is appropriate for both the USAF and NASA. Back in 1970, the idea was that the Air Force would use the shuttle orbiter extensively, to keep the costs down. Look where that got us.

Let's not tailor the VSE into something that "needs" EELV just because we believe USAF & NASA dual use will save some money. An EELV only VSE allowing some military types to collect rocks, pose for pictures and wave the flag ain't worth the money.

And, EELV will no more transform into genuine-RLVs than shuttle derived. Indeed, if NASA EELV purchases are holding down the cost for the USAF there will be strong pressure to resist new systems like t/Space.

NASA (in my opinion) should be building destinations for private sector humans-to-LEO and eventually private sector humans to the Moon.

Open the Moon to private development then send NASA on to Mars. EELV cannot do Mars.[/color:post_uid0]


Give someone a sufficient why and they can endure just about any how

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#36 2005-06-07 11:10:18

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

Re: Shuttle derived revival - Space.com

[color=#000000:post_uid0][i:post_uid0]Bush will choose EELV[/i:post_uid0]

Probably true;

and thus our civilian space will remain "The Emperor's New Space Program" - - lots of pretty pictures but nothing that really matters.[/color:post_uid0]


Give someone a sufficient why and they can endure just about any how

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#37 2005-06-07 11:19:32

clark
Member
Registered: 2001-09-20
Posts: 6,253

Re: Shuttle derived revival - Space.com

[color=#000000:post_uid0]

and thus our civilian space will remain "The Emperor's New Space Program" - - lots of pretty pictures but nothing that really matters.[/quote:post_uid0]

How can you be so close Bill, but miss it?  big_smile

If EELV cannot get us to Mars...

You know, some side research I engage in, "for fun", is learning more about gravitional constants and the property of large orbiting mass's (also known as in-laws, but I digress).

So what does this have to do with anything? Nothing, really. Just meandering... damn orange pills.

Anyway, it seems that if EELV can only get as far as the Moon, then it might behoove the space community to hit upon this idea and point out that while VSE is a journey, it is a journey beyond the Moon. Instead of licking our chops at what may come with Moon venture, ignore it and demand to see how any such plan fits within the overall framework of going on to Mars.

But ze lezders, ze arze zilent!

At least that's the beauty of t/Space from my perspective- to LEO, after that, choose the destination. That's what VSE should be all about.[/color:post_uid0]

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#38 2005-06-07 11:31:17

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

Re: Shuttle derived revival - Space.com

[color=#000000:post_uid0]

But ze lezders, ze arze zilent![/quote:post_uid0]

Michael Griffin knows he needs HLLV and he knows what you say about Rumsfeld and the Air Force. We will see, soon enough.

t/Space is proving damn inconvenient for Big Aerospace.

The ISDC program was printed saying the Lockheed guy, Karas would give a detailed presentation at dinner about their CEV design. Instead, he told some jokes and gave some history.

When asked to discuss Lockheed's CEV, his expression was priceless and his answer simple: "No!"[/color:post_uid0]


Give someone a sufficient why and they can endure just about any how

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#39 2005-06-07 11:35:47

clark
Member
Registered: 2001-09-20
Posts: 6,253

Re: Shuttle derived revival - Space.com

[color=#000000:post_uid0]But SDV is not the HLLV we need for Mars!

It will only get in the way the day after. Clean sheet HLLV designed for Mars can still be used for the Moon.

Plus, that gives some time for the Musk's out there to try and figure out a cheaper way to do HLLV...[/color:post_uid0]

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#40 2005-06-07 12:18:13

SpaceNut
Administrator
From: New Hampshire
Registered: 2004-07-22
Posts: 17,825

Re: Shuttle derived revival - Space.com

[color=#000000:post_uid0]Hence the joining of Lockheed / Boeing union on the shuttle / eelv fronts to keep each other employeed, to share in all launches from both for the USAF and Nasa.

Going to the moon only time frames (3-4days one way or total 16days launch to spash down) as noted before requires only a minimum lift capacity to accomplish (flags and foot prints) but to do something meaningful would require a launch of proportion to Heavy lift in shuttle sized tanks and mass lift capacity.[/color:post_uid0]

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#41 2005-06-07 12:20:12

Dayton3
Member
Registered: 2002-06-03
Posts: 126

Re: Shuttle derived revival - Space.com

[color=#000000:post_uid0]In all fairness.   George Bush #43 didn't move to Texas. 

His father moved ther to strike out into the oil business when the current president was still a small boy.[/color:post_uid0]

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#42 2005-06-07 12:30:40

SpaceNut
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From: New Hampshire
Registered: 2004-07-22
Posts: 17,825

Re: Shuttle derived revival - Space.com

[color=#000000:post_uid0]We soon will know the status of SDV [http://www.comspacewatch.com/news/viewnews.html?id=1026] NASA Seeks to Develop Shuttle Derived Heavy Launch Vehicle[/url]

According to NASA sources, the Exploration Systems Mission Directorate has recommended (internally) that NASA pursue development of a heavy lift launch system based, in part, on the current Space Shuttle.

Such a Shuttle-derived Launch Vehicle (SDLV) would be capable of placing 80-100 metric tons of payload into Low Earth Orbit (LEO).

NASA is expected to formally reveal its SDLV plans in the first week of July.

[/quote:post_uid0][/color:post_uid0]

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#43 2005-06-07 13:13:08

RobertDyck
Moderator
From: Winnipeg, Canada
Registered: 2002-08-20
Posts: 5,881
Website

Re: Shuttle derived revival - Space.com

[color=#000000:post_uid0]I think a good SDV is Shuttle-C with 3 SSMEs in a recoverable engine pod, with 2 OMS pods each with an RCS pod. It's perfect for launching heavy cargo into LEO. However, you only need one such engine pod. The military always buys at least 2 of everything, that's so an enemy doesn't have a single vulnerable point they can hit. But this isn't combat, this is science and commercial. Commercial industry demands that any fixed capital investment must be used continuously; don't buy something just to let it sit of a shelf. If it's expensive but critical, make sure there is vendor support so it can be repaired or replaced when needed, but don't buy a second until [i:post_uid0]after[/i:post_uid0] the first one is scrapped. Any HLLV will not have a launch schedule sufficient to keep even one vehicle busy. If something catastrophic happens to Shuttle-C then an orbiter can be pulled apart to build a new engine pod.

After Shuttle-C is available for LEO, then build Shuttle-Z for direct throw to interplanetary trajectory. Same ET, SRBs, VAB, launch pad and ML, but replace the engine pod. That's one reason I only want to see one Shuttle-C engine pod. I feel the second engine pod should be Shuttle-Z: expendable, 3 RS-68R engines, no OMS at all, no RCS, no thermal blankets nor ablative heat shield nor parafoil nor landing air bags. Add a side-mount upper stage (one RS-68R) and you should be able to throw a Mars Direct or DRM habitat directly to the Moon.

I know, there will be people who say skip Shuttle-C and only build Shuttle-Z. But remember I said the Lunar Transit Vehicle would be lifted to LEO, then crew transferred via space taxi. Since the LTV would be reusable, subsequent missions would only require fuel for the LTV (launched on a single Delta IV Heavy) and another space taxi. Yes, the space taxi would be parked attached to ISS until the crew returns. That means orbital storage time in weeks. Soyuz has 180 days (6 months) orbital storage time, but the normal configuration only has 14 days life support. Don't you think American engineers can do as well? HL-20 was designed with 3 days life support, but X-38 was designed for 4 days life support and 4,000 days orbital storage time.

One design requirement that the industry has realized, is flexible configuration for different missions. EELV has several options, SDV will as well. Shuttle-C and Shuttle-Z are two configurations for what is really a single SDV. Shuttle-Z can be further modified by enlarging the upper stage, and/or replacing SRBs with 5-segment ones. The ultimate evolution of Shuttle-Z would require modification to the external tank, replace the siamesed LOX tank with a cylindrical one that permits stacking upper stage and payload on top. That changes stresses so it's quite radical, but it has a name: Ares.[/color:post_uid0]

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#44 2005-06-07 14:14:45

Dayton3
Member
Registered: 2002-06-03
Posts: 126

Re: Shuttle derived revival - Space.com

[color=#000000:post_uid0]All of us here should be rejoicing. Not whining.

If NASA is seriously committing to a renewed Heavy Lift launch capability, then it means we're ultimately going to see manned missions beyond Earth orbit. 

No currently planned Earth orbital missions require heavy lift.

And I don't really care if the plan is to keep Lockheed or Boeing employees or NASA workers on the job.[/color:post_uid0]

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#45 2005-06-07 14:26:35

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

Re: Shuttle derived revival - Space.com

[color=#000000:post_uid0]All of us here should be rejoicing. Not whining.

If NASA is seriously committing to a renewed Heavy Lift launch capability, then it means we're ultimately going to see manned missions beyond Earth orbit. 

No currently planned Earth orbital missions require heavy lift.

And I don't really care if the plan is to keep Lockheed or Boeing employees or NASA workers on the job.[/color:post_uid0][/quote:post_uid0]
[color=#000000:post_uid0]:up:  :up:[/color:post_uid0]


Give someone a sufficient why and they can endure just about any how

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#46 2005-06-07 14:43:56

clark
Member
Registered: 2001-09-20
Posts: 6,253

Re: Shuttle derived revival - Space.com

[color=#000000:post_uid0]

If NASA is seriously committing to a renewed Heavy Lift launch capability, then it means we're ultimately going to see manned missions beyond Earth orbit. 

No currently planned Earth orbital missions require heavy lift.
[/quote:post_uid0]

Going to the moon does not require HLLV or SDV. It can be done without HLLV or SDV.[/color:post_uid0]

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#47 2005-06-07 15:39:02

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

Re: Shuttle derived revival - Space.com

[color=#000000:post_uid0]

If NASA is seriously committing to a renewed Heavy Lift launch capability, then it means we're ultimately going to see manned missions beyond Earth orbit. 

No currently planned Earth orbital missions require heavy lift.
[/quote:post_uid0]

Going to the moon does not require HLLV or SDV. It can be done without HLLV or SDV.[/color:post_uid0][/quote:post_uid0]
[color=#000000:post_uid0]"Yes, but it would be silly"

Guess who said that! Thanks for the set up line.  big_smile[/color:post_uid0]


Give someone a sufficient why and they can endure just about any how

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#48 2005-06-07 17:07:28

Commodore
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From: Upstate NY, USA
Registered: 2004-07-25
Posts: 1,021

Re: Shuttle derived revival - Space.com

[color=#000000:post_uid0]

If NASA is seriously committing to a renewed Heavy Lift launch capability, then it means we're ultimately going to see manned missions beyond Earth orbit. 

No currently planned Earth orbital missions require heavy lift.
[/quote:post_uid0]

Going to the moon does not require HLLV or SDV. It can be done without HLLV or SDV.[/color:post_uid0][/quote:post_uid0]
[color=#000000:post_uid0]Putting any decent sized structures on it, or at least the machinery to build them will be very difficult without a HLLV.

It should be noted that HLLV is not for manned flight alone. One reason the Prometheus program, specifically JIMO, was put on the back burner was the lack of launch capability.[/color:post_uid0]


"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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#49 2005-06-07 18:04:45

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

Re: Shuttle derived revival - Space.com

[color=#000000:post_uid0]

I think a good SDV is Shuttle-C with 3 SSMEs in a recoverable engine pod, with 2 OMS pods each with an RCS pod. It's perfect for launching heavy cargo into LEO. However, you only need one such engine pod.

After Shuttle-C is available for LEO, then build Shuttle-Z for direct throw to interplanetary trajectory. Same ET, SRBs, VAB, launch pad and ML, but replace the engine pod... Add a side-mount upper stage (one RS-68R) and you should be able to throw a Mars Direct or DRM habitat directly to the Moon.

I know, there will be people who say skip Shuttle-C and only build Shuttle-Z. But remember I said the Lunar Transit Vehicle would be lifted to LEO, then crew transferred via space taxi. Since the LTV would be reusable, subsequent missions would only require fuel for the LTV (launched on a single Delta IV Heavy) and another space taxi. Yes, the space taxi would be parked attached to ISS until the crew returns. That means orbital storage time in weeks. Soyuz has 180 days (6 months) orbital storage time, but the normal configuration only has 14 days life support. Don't you think American engineers can do as well? HL-20 was designed with 3 days life support, but X-38 was designed for 4 days life support

The ultimate evolution of Shuttle-Z would require modification to the external tank, replace the siamesed LOX tank with a cylindrical one that permits stacking upper stage and payload on top. That changes stresses so it's quite radical, but it has a name: Ares.[/quote:post_uid0]
Oh here we go again... I think such an SDV is [b:post_uid0]not[/b:post_uid0] good.

For crying out loud, forget this reuseability nonsense... its going to cost hundreds of millions or billion or two to develop this engine pod, which is for intents and purposes a brand new and entirely independant space vehicle with multiple operational modes. Also, it will be carrying SSMEs, which are very expensive to maintain, and there is a decent risk that the pod would simply fail to return. Its just not worth it, just use a pair of cheap $15M RS-68R engines and be done with it for goodness sakes.

The whole point of going the SDV route in the first place is to eliminate as much development cost as possible, [b:post_uid0]not to introduce new technology[/b:post_uid0] (see Shuttle upgrade costs wildly out of control) and to achieve efficent HLLV capability with the [u:post_uid0]minimum investment[/u:post_uid0]. The engine pod idea just doesn't make any sense. A clear cut-and-dried case of [i:post_uid0]simple expendable = good[/i:post_uid0] versus [i:post_uid0]new, complex reuseable = bad.[/i:post_uid0]

It doesn't make any sense to go a build two [u:post_uid0]different[/u:post_uid0] HLLV designs if one will do, as that will save big on development costs. I don't think that side-mounting like Shuttle-Z is a good idea, because of the much increased amount of pitch strain on the stack will greatly reduce efficency, since you have to burn more fuel to stay upright.

So we build an in-line vehicle like Magnum, except using SRBs instead of flyback Kerosene boosters, with an option upper stage for heavy-duty payloads and with two or three main engines. No need to operate two lines of incompatible external tanks and engine arrangements, no pitch loading or aerodynamic inefficencies from side mounting, and just perhaps capability for man-rating.

As you are so fond of pointing out Robert, that the delta-v to get to the Moon's surface isn't much different then getting to Mars via aerobraking, then even the full 120MT class SDV wouldn't be powerful enough to deliver a DRM HAB to the Moon in one shot. Its also well known that I think MarsDirect is impossible with SDV unless it is equipped with a nuclear upper stage (which adds a whole host of problems).

Absolutely we should skip Shuttle-C, why would we need to develop it at all if we are building a second, different, better launcher? This LTV you describe will also require too much fuel mass to be launched by a single Delta-IV HLV, since more then half of your payload is propellant for a Lunar mission, and Delta is about half the size of SDV.

You can't park the crew taxi at the ISS either (if it even exsists a decade from now), because the SDV should be launched in [b:post_uid0]equitorial orbit[/b:post_uid0] to avoid the ~20-25% payload penalty, and you don't have enough fuel in the taxi for a huge inclination change.

Oh, and the X-38 only has LSS for nine hours, not four days, if memory serves.

Edit: If each flight of the engine pod costs half what twin $15M expendable RS-68 engines do for recovery, refurbishing, and reintegration then you still need to fly about twenty times to make up for a $500M development cost. Nearly fourty with a $1Bn development. For comparison, the ESA's ATV costs about $500M to develop in 1998 dollars according to Astronautix.[/color:post_uid0]


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

The glass is at 50% of capacity

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#50 2005-06-07 21:56:10

GregM
Member
Registered: 2005-01-16
Posts: 30

Re: Shuttle derived revival - Space.com

[color=#000000:post_uid0]

So, how do you see it? NASA and Griffin that is.[/quote:post_uid0]

So how do I feel? Well, I take a somewhat different approach than folks here I guess. I see the American civil space program as just that – a government program. As a government organization, it operates on different paradigms than other types of projects or organizational structures. We all sometimes tend to forget that NASA is just another arm of the US federal government. It is both hostage and benefactor to that reality. Issues such as spending funds in different parts of the country (spreading the money around), political attitudes of the day, public support, etc. are all necessary operating considerations. It is also has a complex relationship with the military-industrial complex, and all of the issues related to that. That will never change as long as NASA remains an arm of the federal government. So, I tend not to look at what I would personally want to see happen – but rather tend to try to envision what is likely to happen when taking into consideration all of the constraints and opportunities that NASA operates within. What I want really doesn’t matter. What is likely to happen does matter. So that said, I would expect the following to play out, based on the situation right now (tomorrow the situation may change and none of this may be valid).

1) The VSE is going to take hold and become NASA’s primary reason for existence. I would have not been so sure up until recently, but the huge organizational shake-up and reformation required to make NASA a VSE-centric organization has begun. This is the most significant thing to happen to NASA in over 30 years. Massive layoffs, transfers, and hiring, shutdowns, and startups have begun at NASA centers – and are likely to continue through to completion. Today for example, pink slips and transfers for many of NASA’s top brass were issued.  Toes are not only  being stepped on, but are being amputated if they do not support the VSE. None of this could have happened unless there was the blessing of the executive and legislature to do so. It is indicative of real commitment to proceed with the VSE at high levels. This is very significant and cannot be underestimated. Power is shifting.

2) Indications are that the Apollo-type project model will be used for VSE (obviously with many modifications because of the time gap). Industry will construct much of the machines and materials, but NASA will be firmly in program design and control.

3) Existing NASA centers that can contribute to the VSE will get lots of work. Ones that can’t will suffer.

4) Budgets will not be unlimited. Some NASA projects and programs that do not support the VSE will be delayed or cancelled.

5) The overriding prerogative in the near term will be to get the shuttle flying and finish the station. This is mostly just to get the damn stuff out of the way and off the plate. It is nothing more than an obstacle to getting on with the VSE. If they could, they would walk away from it right now – but  those ISS treaty obligations get in the way. Look for NASA to do anything it can to reduce those treaty obligations in order to get on with VSE.

6) If another shuttle is lost, the program will be shut down. ISS will be reconfigured in whatever form possible to continue on. The Russians don’t want to walk away from it, and will keep it going in that unlikely contingency.

6) The primary focus outside of fulfilling ISS commitments (in the next 5 years) will be to build a new manned spacecraft to replace the shuttle ASAP. Getting the Constellation project’s CEV flying by no later than 2011 will become paramount as 2010 approaches.

7) NASA will go with a heavy lift SDV launcher for big unmanned cargo, for reasons I described earlier in this post (and won’t get into again). Also there is a better than 50/50 chance that CEV will fly out of LC-39 on a STS SRB-derived LV, although that is less certain than the SDV heavy launcher happening.

8) Assuming that the VSE survives into the next presidential term or two, I imagine an actual return to the Moon in a period between 2014-2017. What happens in terms of permanency regarding lunar habitation is very fuzzy right now. A lot up in the air about that. Could be as little as a dozen expeditions lasting 2-4 weeks each, or a much as permanent bases.

9) I would be surprised to see a Mars expedition mounted before 2025. More likely 2030-2035. This date could be accelerated if the political desire is there to make it happen (read spending megabucks), or it could be put off indefinitely if the political winds blow ill. An expedition to a near-earth asteroid or Lagrangian stations may happen before the Mars attempt as a rehearsal.

10) IF a human Mars program is reasonably successful, then the floodgates will open. A barrier will have been crossed and human exploration of the solar system will commence. I would expect expeditions to the larger main belt asteroids, and eventually Callisto in a post 2050 time frame.


So, that is my best guess at what will play out at this time. Some folks may not agree with all I have laid out – and I don’t blame you. Hell, I don’t even personally agree with all of what I think is likely to transpire – but that is the way I think it will play out IF things continue on their current track unabated. And that is a BIG “IF”.  A lot of unpredictable will occur in the next 30 years, and will likely affect this prediction. But hey, that’s how I see it playing out at this time.[/color:post_uid0]

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