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#1 2004-09-13 10:25:52

Mark S
Banned
Registered: 2002-04-11
Posts: 343

Re: SRB booster for CEV

The Space Review has a new piece about a scheme to use a shuttle SRB to boost the CEV.  Astronaut Scott Horowitz seems enthusiastic about the idea.  However, I have a few misgivings.  It is a solid rocket booster, and while such rockets are pretty reliable compared to their liquid equivalents, they can't be shut down during a launch failure.  Also, it would take plenty of time and money to build this new SRB-based booster.  The Delta IV and Atlas V have already been developed and tested.  I tend to think that man-rating these boosters will be less difficult than some people think, and the same process will have to be applied to the new booster anyway.

That being said, there are some interesting things to be found in the article.  Knowing that Rocketdyne still has a dozen J-2's and could produce more is very encouraging, as we will need these rockets somewhere down the line in the race to the moon.


"I'm not much of a 'hands-on' evil scientist."--Dr. Evil, "Goldmember"

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#2 2004-09-13 10:40:03

SpaceNut
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Re: SRB booster for CEV

Yup started talking about concept on the 10th under the Post central for information on CEV 2 (Pages 1 2 3 ..8 )
...continue here.
page 8
http://www.newmars.com/cgi-bin....ntry115

Basically a SDV in which the boosters are already man rated. As for solid motor shutdown large exstiguisher and damper doors at nozzle end would probably be enough to shut it down. Still would need to jetison them and fire up the upper stage for seperation followed by the launch escape tower process.

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#3 2004-09-13 10:52:46

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

Re: SRB booster for CEV

Another thread on Thiokol RSRM with an upper stage.

Looking at this, =IF= demand existed to fly 500 5 segment SRBS with an upper stage made from 2 RL-10s launch costs for cargo only would fall below $1000 per pound to LEO and in best case scenarios, fall below $250 pound to LEO.

Best case (fantasy?) scenario:

5 segment SRB costs $15 million (based on a 500 unit purchase)

2 RL-10s cost $ .5 million (based on a 1000 unit purchase)

1 upper stage fuel tank costs $3 million? (based on a 1000 unit purchase) 

Miscellaneous stuff including payload stabilization until collected costs another $3 or $4 million.

(Nore - Northrup inteds their new fuel tank to be re-useable as living space and the guidance systems could be collected and returned to Earth for re-use after cargo is collected)

Lets say $20 million is our fantasy launch price. Based on statements from ATK Thiokol's Mike Kahn, such a system with 87% or 88% mass fractions and lighter upper stage tanks could well throw 80,000 pounds to LEO at a net price of $250 per pound.

Develop a non-man rated cargo only version as well.


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#4 2004-09-13 11:44:15

GCNRevenger
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Re: SRB booster for CEV

"As for solid motor shutdown large exstiguisher and damper doors at nozzle end would probably be enough to shut it down."

No, no it wouldn't How exactly do you intend to stop the chemical reaction, which has its own oxidizer, that is producing 3.3 million pounds of thrust? Just dumping in an inert gas isn't going to make it shut down. Nor can you simply plug the thing, no practical door could hold back that kind of pressure and heat... And it gets better, as a solid rocket booster does tend to fail almost instantly if the fuel grain is damaged, and very rapidly if there is a casing leak. I ought to point out, that the upper stage can't simply light up its Centaur and boost clear, no, it needs eight G thrust to escape safely from an exploding booster.

I am not a big fan of using it for cargo duty either, since too many small pieces leads to an expensive project no matter how cheaply they can be launched for. And they still can rendevous on their own without a tug or maneuvering systems either... a larger rocket albeit more expensive can make for a cheaper overall program: don't ever lose sight of why you are building your rocket, which is one reason we got stuck with Shuttle in the first place.

I also don't think that a massive order for parallel launches would be practical to reduce launch costs, as many things about rockets are expensive soley because they are expensive, not because of a lack of economies of scale. Such a huge flight rate would also require multi-billion-dollar facilities and logistics investment.

Awfully skeptical about that 80,000lbs figure... too good to be true.


"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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#5 2004-09-13 12:01:06

SpaceNut
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Re: SRB booster for CEV

To burn the fuel you need to generate a heat source to not only start the reaction but to keep it going as well. To stop this super cooling it should be enough. If all else fails seperate the segments above the failing unit.

Maybe it is time to rethink about how SpaceShipOne is doing just that with its engines.

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#6 2004-09-13 12:10:55

Mark S
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Re: SRB booster for CEV

SpaceShipOne uses a hybrid engine, which has superior safety systems to a pure solid (at the expense of performance.)  If the engine fails, you cut off the oxidizer or dump it completely.

Thrust termination was considered after the original flights of STS.  It would involve blowing off the nose of the SRB so equal amounts of exhaust would exit the forward and aft ends of the booster.  It doesn't take a lot of imagination to see the problems with this scheme.


"I'm not much of a 'hands-on' evil scientist."--Dr. Evil, "Goldmember"

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#7 2004-09-13 12:17:41

GCNRevenger
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Re: SRB booster for CEV

How exactly do you intend to supercool the entire burning fuel core, and do it within one second, without it being too heavy? You also cannot separate the booster segments during flight, that would definatly never work and would add too many.

The SS1 engine is a hybrid rocket, not a true SRB.


"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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#8 2004-09-13 13:24:14

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

Re: SRB booster for CEV

Awfully skeptical about that 80,000lbs figure... too good to be true.

That would need to be based on adjusting the mass fraction and going 100% expendable rather than re-cycled.

A 4 segment SRB has 192,000 pounds of aluminum and the like and is intended to be re-used 20 times or so. Its also based on 1970s metallurgy.

Swap in composites or even fiberglass at certain points and every pound shaved from the SRB adds to the 2nd stage payload.

Move that 85/15 figure to 87/13 and you add 25,600 pounds to your 2nd stage with no loss of performance.

Move that 85/15 figure to 90/10 and you can add 64,000 pounds to the estimated 40K - 50K Mike Kahn and Scott Horowitz are talking about.

Go to a 5 segment SRB and J-2 and the improvement is even greater.

My understanding is that SRB improvement for the orbiter was not helpful since increased thrust would exceed other engineering tolerances and require re-working the orbiter framework. The 5 segment SRBs would have meant mostly the ability to throttle back the SSMEs.

A new in line rocket: SRB + LH2/LOX upper and the SRB can be as powerful as it can be.


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#9 2004-09-13 13:28:44

BWhite
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From: Chicago, Illinois
Registered: 2004-06-16
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Re: SRB booster for CEV

How exactly do you intend to supercool the entire burning fuel core, and do it within one second, without it being too heavy? You also cannot separate the booster segments during flight, that would definatly never work and would add too many.

The SS1 engine is a hybrid rocket, not a true SRB.

I am not a big fan of man-rating this thing. GCNRevenger once addressed this by raising the need for a 8 or 10 gee escape tower and - - well - - I threw in the towel on this idea for crewed flight.

But with a 90/10 mass fraction, 5 (or 6?) segment SRB and a new lighter LH2/LOX tank for the upper stage and we should be well below $1000 per pound for cargo.


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

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#10 2004-09-13 13:29:12

Mark S
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Re: SRB booster for CEV

In response to BWhite:

The fuel fraction of SRBs had been enhanced in the past with the all-black, filament-wound casings developed for Vandenberg launches.  After Challenger, the casings were re-examined and discovered to not meet specifictions.  However if the SRB is going to be expendable, these casings might meet that lower standard.

The purpose of the 5-segment  SRB for the standard shuttle is to increase payload delivered to higher orbits and ISS.  The limiting factor is how much payload the shuttle could return in an abort scenario.  The new boosters will not allow an increase in max payload, just an increase in how far it can go.  Their primary benefit is what they can do to enhance a future shuttle-derived rocket.


"I'm not much of a 'hands-on' evil scientist."--Dr. Evil, "Goldmember"

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#11 2004-09-13 14:56:45

GCNRevenger
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Re: SRB booster for CEV

There is another expense to take into account Bill that I worry about, that just building the thing is only a part of the price-tag, a good chunk of the money is going to go into launch operations. Using the old VAB/Crawler/Pad-39 and the army of Shuttle engineers who just won't go away may be the millstone round' the neck of any Shuttle-derived vehicle of any kind, and is partially responsable for making Shuttle the expensive nightmare it is today. Even if it costs $20-30M each to build, how much will it cost to fly?

Personally, I don't see how the EELVs would be so expensive if not for the flight operations. Surely the Delta-IV and Atlas-V can't cost $80-90M each just to construct... in fact, I can't imagine that a core costs much more expensive to build then this theoretical Thiokol medium/heavy launcher.

And again again, REMEMBER, remember the question... WHY do you want to build this rocket? To "lower cost per pound" is not a valid reason, cost per pound of what? A launcher for space station componets? Smallish payloads to Moon/Mars? Satelites? Do not lose sight of the destination when selecting the method to get there.


"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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#12 2004-09-13 17:11:51

BWhite
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From: Chicago, Illinois
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Posts: 2,635

Re: SRB booster for CEV

In response to BWhite:

The purpose of the 5-segment  SRB for the standard shuttle is to increase payload delivered to higher orbits and ISS.  The limiting factor is how much payload the shuttle could return in an abort scenario.  The new boosters will not allow an increase in max payload, just an increase in how far it can go.  Their primary benefit is what they can do to enhance a future shuttle-derived rocket.

I think I said that. 5 segment SRBs don't really help the shuttle orbiter all that much because (IIRC) the orbiter stack cannot really handle the extra thrust and the SSMEs would need to be throttled back.

That said, if you put a J-2 or other LH2/LOX upper stage on a 5 segment SRB, why wouldn't that increase payload to LEO or allow a smaller payload to end up in a higher orbiter and if the destination is beyond LEO isn't that the same thing?

= = =

GCNRevenger - - I agree form follows function. Why are we leaving LEO?

If the Bush vision is to let a few NASA types collect rocks and thats all for the next 50 years then we don't hardly need anything.

Next, if you read the Congessional committee comments, the shuttle infrastructure types do not seem willing to let the oribter die an early death.

If the SRB + J2 were deployed in 2006 or 2007 they could be launched at times when the orbiter launch window was closed for CAIB reasons. Folks get paychecks and janitors clean KSC either way. Why not launch some cheap extra rockets?


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#13 2004-09-13 17:55:44

GCNRevenger
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Re: SRB booster for CEV

The J-2 doesn't have the best of specific impulse though, I wonder if a pair of smaller RL-60s would do... theoreticly, they will put out 65,000lbs of thrust in the production model at ~460sec specific impulse... Smaller engine, no need to re-learn how to make J-2 engines, higher performance.

Well, what function(s) do you want the Thiokol medium launcher to accomplish? Then think about if the launcher is the right choice or no is what i'm trying to get across.

"Next, if you read the Congessional committee comments, the shuttle infrastructure types do not seem willing to let the oribter die an early death.

If the SRB + J2 were deployed in 2006 or 2007 they could be launched at times when the orbiter launch window was closed for CAIB reasons. Folks get paychecks and janitors clean KSC either way. Why not launch some cheap extra rockets?"

Launch them where? Launch what? In the time between 2006 and 2010, NASA isn't going to have much money for anything but to start building capsules or build the Thiokol booster or do major updates to the EELV(s) it looks like. Pick one. Unless you can build CEV, then it doesn't matter, you won't be launching rockets anywhere even if you could because you'd have no payload. In the future, when there is a need for 25MT-class payloads cheaply on a regular basis, the question should be asked if we should stick with expendable rockets at all.

I also must confess that I am losing faith in Shuttle Derived Anything, 50/50 undecided, because it requires that KSC be kept operating. I fear that the costs associated with keeping KSC going will be so large that they threaten to derail the whole thing from sheer buracracy that NASA won't axe workers that need to go... Shuttle doesn't cost $4.3 Billion Dollars a year to replace glass tiles after all. Plus, it is questionable if any SDV design could be done that would be able to lift more than 120MT, which makes a MarsDirect or any large operation iffy... A little weight creep, and its all over.


"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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#14 2004-09-13 18:12:11

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

Re: SRB booster for CEV

The J-2 doesn't have the best of specific impulse though, I wonder if a pair of smaller RL-60s would do... theoreticly, they will put out 65,000lbs of thrust in the production model at ~460sec specific impulse... Smaller engine, no need to re-learn how to make J-2 engines, higher performance.

Valid comments. . .

Well, what function(s) do you want the Thiokol medium launcher to accomplish? Then think about if the launcher is the right choice or no is what i'm trying to get across.

Great question! What exactly does "exploration" mean in the context of the current proposed VSE?

But if we skip the "Direct" in Mars Direct, 4 or 5 of these SRB thingees could be used to build a Mars craft with on orbit assembly.

Suppose 66K to LEO with a 5 segment plus 2 RL-60s or whatever. Lift a 30 tonne Mars habitat without crew. Then lift 30 tonnes of fuel in multiple stages. The RL-60s and J-2s are re-startable so assemble these various boosters as the Mars insertion stage. Side by side or in a "train" - - heck I don't know about that but 4 upper stages with 120 tonnes of fuel docked with 1 upper stage with a 28 - 30 tonne habitat.

Fly up the crew in Kliper, 2 Soyuz; a man-rated Delta IV CEV or a handful of Falcon.

Light the 4 upper stages and off to Mars.

=IF= Scott Horowitz is correct that a 5 segment SRB plus liquid upper would cost less than $100 million, then 5 would cost $500 million.

Not bad for the lift portion of doing Mars.


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

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#15 2004-09-13 18:19:19

GCNRevenger
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Re: SRB booster for CEV

Mmmmmm but orbital assembly on that kind of scale is a proven disaster both engineering and cost wise, plus you have the lack of efficency because of the extra tank & engine weight and the higher risk of failure... There is a good reason Bob-Z wants to go direct. Oh, and don't forget fuel boiloff and Centaur batteries dying, and the lack of any way to connect these pieces together.

So, is it really cheaper to go with the Thiokol booster then a HLLV? ...Oh, and Klipper isn't happening, neither is a manned Falcon-V.

Mr. Horowitz may be correct that you can build such a booster for $100M or less, but that is not the question, the question is how much will it cost to FLY the thing. The cost of keeping the VAB, Pad 39, etc all open and operating?

CEV should fly on EELV for safety, plus EELV can be modified to achieve 80,000lbs class payloads without too much trouble, and so how much will it cost to buy more of them Versus keeping the Thiokol launcher line and all the KSC facilities open at the same time? ...For that matter, how much is $500M compared to the cost of the actual Mars vehicle?

Edit: Keep in mind, that a hypothetical HLLV with resueable boosters probobly wouldn't cost much more than $500M a flight either.


"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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#16 2004-09-13 18:49:17

BWhite
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From: Chicago, Illinois
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Posts: 2,635

Re: SRB booster for CEV

More good points. So lets do a thought experiment.

Suppose hurricane Ivan had obliterated the Kennedy Space Center. How much do you need to launch a 5 segment SRB + liquid upper?

A gantry and a crane, correct?  Build on Pad 39 after the wreckage is cleared awy.

Stack the stuff up a segment at a time on the launch pad. Its not manned rated, that 8 or 10 gee escape tower scaring the heck out of me.

I agree with you that a clean sheet EELV HLLV might prove a better option, but this SRB + liquid upper does provide an interesting benchmark to shoot against.

And if we do build a permanent base on the Moon, such a thingee can throw bulldozers, etc. . . fairly easily.

A big RLV? Yup. But since Congress won't fully fund the VSE, finding a solution within what we can spend seems to be the challenge.


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

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#17 2004-09-14 05:46:39

SpaceNut
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Re: SRB booster for CEV

Well the E in EELV is expendable in that we do not care what happens with it and even though An SRB is reusuable should we care about that feature, probably not.

As for the launch pad cost what quantity difference is there for a launch of the EELV versus the SRB booster design?

Is it not cheaper per launch if those people are actually working not idle, more launches per time period lower cost.

It might be possible from the SRB booster unit to have more launches since build time would be by far less than EELV continuing to lower cost.

In a strapped economic budget period, what ever that works for a given cost that is important not just if it is cheap.

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#18 2004-09-14 06:06:33

comstar03
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Re: SRB booster for CEV

Throw this way, or that way, what about the environment and reusability. If we go down the track of expendable, then we are throwing money away, that is stupid.

I thought humanity was getting better and advancing space development and expanding the frontiers, I was wrong if they go down the track of expendable modules for the launch vehicle.

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#19 2004-09-14 08:13:45

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

Re: SRB booster for CEV

Throw this way, or that way, what about the environment and reusability. If we go down the track of expendable, then we are throwing money away, that is stupid.

I thought humanity was getting better and advancing space development and expanding the frontiers, I was wrong if they go down the track of expendable modules for the launch vehicle.

What if we eliminate the parts that need to be re-used? That is what mass fractions are all about.

The current Thiokol RSRM (used for the shuttle) has an 85/15 mass fraction. 85% of lift off weight is fuel that is burned and 15% is other stuff that is either discarded or re-cycled. ATK Thiokol says re-used but some say re-cycled is a better word.

Suppose by using light weight plastics and composites we can move the mass fraction to 95/5? Probably way too optimistic, today, but as material technology improves, who knows?

But if we can exceed a 90% fuel to dry weight ratio then there is very little left to discard or dispose of. No need to re-use or re-cycle.

What will the mass fraction be for any conceivable RLV?

= = =

If the mass fraction can be improved enough, but used only for lifting things like bulk goods or upper stages (a lightweight tank filled with LH2/LOX and some RL-60s) the lower lift cost will offset the occassional failure due to flimsy construction.

I cannot advocate putting people on such a thingee, but so what? Cargo flys cheap and crew flies luxury class RLV.


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

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#20 2004-09-14 09:47:52

GCNRevenger
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Re: SRB booster for CEV

First off, the SRB isn't really "reuseable" persay, more like "refurbishable;" the whole thing has to be broken down into its segments, carefully inspected, refueled, then shipped back to the Cape' for assembly. This process is simply not that easy, costing nearly as much as simply building a brand new booster, and obviously takes nontrivial amounts of time to accomplish.

As for environmental concerns, throwing away the rocket  boosters themselves isn't so bad, all you really get is some harmless Alumina powder and metal bits, which aren't really dangerous... There is a concern about solid rockets though, that they do produce some fairly nasty exhaust products, launching dozens of these could add up to nontrivial environmental damage... Hydrocarbon and Hydrogen rockets are clean though.

Oh, and I think that a 90% mass fraction would be pushing the limits of reasonable, most RLV concepts weigh in around 97-98%.

"If we go down the track of expendable, then we are throwing money away, that is stupid."

Again, why do you want to build the rocket is the first question... if you are going to send a dozen flights up a year for a small Lunar program and a few space station flights, then spending the $10Bn (small) to $20-25Bn (large) for an RLV just doesn't make good sense, especially since rockets that can do this job are available for almost zero (sans CEV) development costs, relativly speaking.

For a Mars mission, a vehicle of larger size than any concieveable medium rocket expendable or not is called for in order to minimize (or even eliminate) on-orbit construction of any kind, to minimize duplicity of hardware, and maximize vehicle volume per weight (1 big vs many small). Building a partially reuseable HLLV does seem to be possible, but making a completly reuseable one is just not going to happen.

Later on, down the road, when we need routine access to space on a larger scale (building/tending artifical gravity space stations, Lunar mining, Mars base missions) then it makes sense to think about an RLV, but unless you are looking at high flight rates, then the ELV is the better choice.

My main issue with building the Thiokol Launcher is that it would infact be cheaper or not much more expensive to buy more EELVs since the KSC complex would have to remain open in parallel to the EELV facilities, and that costs could not be controlled at KSC since it is a NASA operation. The Delta-IV pad near the Cape' is theoreticly able to launch 15 flights per year, or the Atlas probobly a similar number.


"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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#21 2004-09-14 09:59:26

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

Re: SRB booster for CEV

Everything being equal, solid rockets have many negative qualities. I have no problem with that.

The big advantage ATK Thiokol has "today" is that they have a proven 99.5% record and the $30-35 million price tag is very well established.

But GCNRevenger is correct, WHY we have a space program should ultimately determine what we build.

= = =

So what is the real "WHY" behind the current VSE?

Some say the real "why" is to help DoD buy EELV more cheaply and the "exploration agenda" is a mere figleaf to make that choice more palatable to the public.

Personally, I don't know how Bush or "OKeefe would define "exploration."

= = =

My main issue with building the Thiokol Launcher is that it would infact be cheaper or not much more expensive to buy more EELVs since the KSC complex would have to remain open in parallel to the EELV facilities, and that costs could not be controlled at KSC since it is a NASA operation. The Delta-IV pad near the Cape' is theoreticly able to launch 15 flights per year, or the Atlas probobly a similar number.

A legitimate point.

On the other hand, KSC means patronage. Congressional support for a program that sustains lots of jobs in a key battleground state (Florida) may mean that a KSC centered exploration agenda will have an easier time in Congress even if it is less than optimal for other reasons.

Edit: A govenrment funded program is going to have pork no matter what vehicle is flown.

That said, suppose a private sector company decided to build a launchpad on the island of Grenada and transport Thiokol segments by barge. What would they need besides a gantry and a crane and a concrete flame trench?


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

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#22 2004-09-14 09:59:56

SpaceNut
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Re: SRB booster for CEV

So how much is Nasa billed for every launch that uses those vehicles for there respective launch pad?

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#23 2004-09-14 11:24:16

Grypd
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From: Scotland, Europe
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Posts: 1,868

Re: SRB booster for CEV

I am with GCNRevenger on this one. It really depends on what we are going to do in space that will decide what sort of vehicle is needed. Reusable launch vehicles will cost a fortune to develop but there use is cheaper and if we need a lot of launches then they will prove to be of worth to develop. But at the moment without a proper sense of where and how we wish to go to then expendable is what we do.

I am an advocate of reusable shuttles with a form of expendable heavier lift to supplement it. But this is through my view of how I view our exploration of space to go, but I expect that we will start with expendable only launches but with the increased emphasis of space then we complete a program to have totally reusable craft.


Chan eil mi aig a bheil ùidh ann an gleidheadh an status quo; Tha mi airson cur às e.

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#24 2004-09-14 11:59:22

SpaceNut
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From: New Hampshire
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Re: SRB booster for CEV

Reusable launch vehicles will cost a fortune to develop but there use is cheaper and if we need a lot of launches then they will prove to be of worth to develop.

Well if we are using the Shuttle as a model of reusability we have failed and that is just on the orbiter. All the rehab that is done to each is way to much cost after each flight. Eliminating the larger portion of the cost of refurbishment is a must under reuseable ships.

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#25 2004-09-14 15:43:11

GCNRevenger
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Re: SRB booster for CEV

The big advantage ATK Thiokol has "today" is that they have a proven 99.5% record and the $30-35 million price tag is very well established...

So what is the real "WHY" behind the current VSE?

Some say the real "why" is to help DoD buy EELV more cheaply and the "exploration agenda" is a mere figleaf to make that choice more palatable to the public.

Personally, I don't know how Bush or "OKeefe would define "exploration."

...KSC means patronage. Congressional support for a program that sustains lots of jobs in a key battleground state (Florida) may mean that a KSC centered exploration agenda will have an easier time in Congress even if it is less than optimal for other reasons.

Edit: A govenrment funded program is going to have pork no matter what vehicle is flown.

The Space Shuttle, as a reuseable launch vehicle, has failed miserably yes, this is not in debate... However, this does not mean that a true RLV cannot be built. We do have the technology right now today this very instant to start work on a two-stage all-flyback vehicle where no componet would be expendable and no major system would require major overhaul between flights.

Large reuseable cryogenic engines, metal heat shield, LOX-augmented jet engines, composit structures and tankage, advanced CAD/CFD design... All of these are readily available with only modest investments in research. I concede that will be very expensive to build with near-term technology, but if you are able to save 90% of your launch costs then this can add up rapidly when you need to launch often.

Anyway, back to the Thiokol launcher and VSE,

Again, the Thikol launcher might cost under $50M a pop to build, but even if the thing were built for free and it cost a billion dollars to assemble, integrate, prep and fly then it doesn't matter... We have to know how much it costs to launch the thing. With Shuttle going for about $1Bn a flight now, how much of that goes to the SRB handling? ...I think its an open question how much it would really cost, but an EELV flight is a pretty known quantity.

I think the reasoning behind VSE goes somthing like this...:

After Columbia, or even a little bit before, it is obvious that the Shuttle era is almost over. The ISS will not ever be very useful, nor will it last a long time, and the duo together essentially bankrupt NASA human spaceflight... Basicly, there wasn't going to be a "next thing," and NASA would be ungloriously gutted when Shuttle is gone, and not without good reason given its astronomical cost. With no clear direction other than "build Shuttle-II... maybe?," that $15Bn budget would be too tempting to protect.

So, now we have the Bush administration trying to put together a "what now?" to keep NASA going, and the decsion was reached for a number of contributing factors... that the project(s) not be destined for LEO, too boring, and nobody will fall for the "$9Bn for ISS for science! honest!" line again. Then the China moon mission angle. Then sustainability too, the program must be cheaper than Apollo and be open-ended. And help make launchers for the military bigger and more available... But mostly to protect NASA from the "robots can do it cheaper!!!" croud and give 2/3rds of NASA's money to Social Security. What it does is give us reliable and sufficently inexpensive access to LEO and cis-Lunar space to sustain small to moderate science & development operations indefinatly without making NASA go broke for really a minimum of development dollars to not do a half-baked job.

Yes, it is possible that keeping KSC open would actually help advance manned spaceflight even if it were more expensive, but I think that NASA simply cannot afford another Shuttle-like situation where launch costs and ISS/STS maintenance utterly bankrupt the agency. If NASA does not do this, then there won't be any NASA anymore... Everything that has to do with Shuttle since the Nixon days has been about one thing: Maximize engineer employment, and like many results when NASA really tries, has suceeded beyond any expectation. I question if NASA has the willpower to fix this hardest of problem: "redesigning" KSC to change course and fulfill a new goal.

So, if NASA does not have the willpower to "fix" KSC to stop maximize manpower and spending, then KSC has to go, and it would be better to start over again... Maybe at the Boeing Delta-IV plant up the coast..


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

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