Heavy Lift an unnecessary impediment?

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RVHM

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vulture4":yax7efd0 said:
What exactly is the mission that we need heavy lift for?
BEO exploration.

vulture4":yax7efd0 said:
We certainly don't have the money for another Apollo, unless you want to campaign for higher taxes, which no one will accept. To borrow from China for a joyride to the Moon is absurd.
If done correctly, a SDHLV can be flown at a lower cost than the current Space Shuttle Program. Saying a HLV must necessarily cost as much as Apollo is a strawman argument.

vulture4":yax7efd0 said:
If we want human spaceflight, RLVs are more important since fuel costs almost nothing.
Yeah, right. I guess hardware refurbishment and a standing army of maintenance workers are for free as well, aren't they?

vulture4":yax7efd0 said:
However if we ever need an HLV, clustering the existing Delta IV and/or just upgrading it with crossfeed and aluminum-lithium tanks would accomplish it at lower cost.
How many Delta IV's would you want to cluster for that? You'd need 11 Common Core Boosters just to come close to the Saturn V in terms of liftoff thrust. On the other hand, it's useless to have a very powerful first stage if your second stage can't bring the payload to orbit. What would you do then, stack 11 Delta IV second stages on trop of the 11 CCBs?

The bottom line is that you can't build a 120 ton-class vehicle by clustering existing EELVs.
 
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MeteorWayne

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rockett":r1luy1gr said:
RVHM":r1luy1gr said:
Pray tell, then, why is SpaceX looking at an F-1 class engine for its Super-Heavy-Lift evolution plans? (you know what I'm talking about, right?)

They have chosen to design a new plan (Falcon X and Falcon XX) instead of just clustering loads of Falcon 9s. And that is NOW.
Wonderful! I would love to see the information on it. Do you have a link?

The point was, though, that back in the day, we did not have on-board computer monitoring systems and such for cut-over or shut-down in the case of an engine failure. .
I don't think that's true. As I recall, the Saturn V had such a system, and one of the launches had an engine shut down early (IIRC, it was the easier to handle center engine)

Pre Posting edit: Yes it was Apollo 13, but it was the 5 engine second stage:

The mission began with a little-known smaller incident: during the second-stage boost, the center (inboard) engine shut down two minutes early. The four outboard engines burned longer to compensate, and the vehicle continued to a successful orbit.
 
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vulture4

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vulture4 wrote:If we want human spaceflight, RLVs are more important since fuel costs almost nothing.

>>Yeah, right. I guess hardware refurbishment and a standing army of maintenance workers are for free as well, aren't they?

Shuttle was our first attempt at an RLV. Some of the design choices were wrong, most seriously the use of SRBs which have to be recovered at sea and rebuilt practically from scratch, the use of an expendable ET, which is the most expensive single component, and the use of heritage facilities and equipment like the VAB, MLPs and crawlers, all of which are expensive to maintain. Foam damage to the tiles has almost disappeared since the ET improvements made after Columbia was lost. But with all that, Shuttle carries almost twice the crew and ten times the cargo of Orion at a lower launch cost.

Obviously to build an RLV thatis practical and safe, we need actual flight testing of the critical systems. That's why theRLV program was started, with the X-33, X-34, DC-X and X-37, each intended to test different concepts for a new generation of RLV. Unfortunately Bush cancelled them all. At least Obama was able to save ISS; had Bush succeeded in terminating it as soon as it was completed we'd now have nothing.

The ISS serves a geopolitical purpose as a catalyst for trust and cooperation between nuclear adversaries. It also provides a destination for commercial launch vehicles. Constellation has no international partners. What practical value does it provide to the American taxpayers?
 
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rockett

Guest
MeteorWayne":3rf1q1zo said:
I don't think that's true. As I recall, the Saturn V had such a system, and one of the launches had an engine shut down early (IIRC, it was the easier to handle center engine)

Pre Posting edit: Yes it was Apollo 13, but it was the 5 engine second stage:

The mission began with a little-known smaller incident: during the second-stage boost, the center (inboard) engine shut down two minutes early. The four outboard engines burned longer to compensate, and the vehicle conti
nued to a successful orbit.
You are correct, to some degree, the center engine shut down prematurely due to pogo oscillation
On previous Saturn flights, these pogo oscillations had occurred during launch. The phenomenon occurred as the fuel lines and structure of the rocket resonated at a common frequency. The resonance tended to amplify in force and potential destruction with each bounce of the “pogo” mechanism. So damaging was the phenomena on the unmanned Apollo 6 mission that an entire outer panel of the Saturn 5 ejected into space
The Apollo 6 mission carried a mock lunar lander of more modest mass than the "full-up" lander which Apollo 13 carried to orbit. With the added mass for Apollo 13, the pogo forces were suddenly a magnitude greater in intensity. A mission report said that the engine experienced 68g vibrations at 16 hertz, flexing the thrust frame by 3 inches (76 mm).
Woodfill said that if the center engine had continued running a few more seconds, the oscillations may have destroyed the vehicle. "That engine was pounding horizontally up and down, a quarter foot, at the rate of 16 times a second," he said. "The engine had become a two ton sledge hammer, a deadly pogo stick of destruction, putting enormous forces on the supporting structures."
What shut the engine down?

"It is, to this day, not fully understood, but it had something to do with fooling the engine’s thrust chamber pressure sensor that pressure was too low," said Woodfill. He has studied the mission report, but says the complete analysis of why the engine shut down isn't included.
"Though the shutdown command came from a low thrust chamber pressure sensor assessment, actually, the engine was operating correctly," he said. " The sensor had nothing to do with the pogo phenomenon. For some inexplicable reason, it was like something sucked the pressure out of the chamber and a sensor turned the engine off. But no one knows exactly why."
Woodfill said those who later examined the situation said it was altogether lucky that the sensor shut down the engine. "Something intervened, stopping the engine from pounding its way from the mount into the fragile fuel tanks. This would have destroyed the Apollo 13 launch vehicle."
http://www.universetoday.com/62672/13-things-that-saved-apollo-13-part-5-unexplained-shutdown-of-the-saturn-v-center-engine/
But they were far from the sophistication of what we have today.

During two launches, Apollo 6 and Apollo 13, the Saturn V was able to recover from engine loss incidents. The N-1 likewise was designed to compensate for engine failures, but the system never successfully saved a launch from failure...

The five F-1 engines were arranged in a cross pattern. The center engine was fixed, while the four outer engines could be hydraulically turned ("gimballed") to control the rocket. In flight, the center engine was turned off about 26 seconds earlier than the outboard engines to limit acceleration.
http://en.wikipedia.org/wiki/Saturn_V
 
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RVHM

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vulture4":308s5ggj said:
Shuttle was our first attempt at an RLV. Some of the design choices were wrong, most seriously the use of SRBs which have to be recovered at sea and rebuilt practically from scratch, the use of an expendable ET, which is the most expensive single component, and the use of heritage facilities and equipment like the VAB, MLPs and crawlers, all of which are expensive to maintain. Foam damage to the tiles has almost disappeared since the ET improvements made after Columbia was lost. But with all that, Shuttle carries almost twice the crew and ten times the cargo of Orion at a lower launch cost.

Obviously to build an RLV thatis practical and safe, we need actual flight testing of the critical systems. That's why theRLV program was started, with the X-33, X-34, DC-X and X-37, each intended to test different concepts for a new generation of RLV. Unfortunately Bush cancelled them all. At least Obama was able to save ISS; had Bush succeeded in terminating it as soon as it was completed we'd now have nothing.

The ISS serves a geopolitical purpose as a catalyst for trust and cooperation between nuclear adversaries. It also provides a destination for commercial launch vehicles. Constellation has no international partners. What practical value does it provide to the American taxpayers?
Yours is a strawman argument. You are comparing RLVs and Constellation as if it's a choice between the two of them and nothing else. There are many viable alternatives to RLVs which are not Constellation.
 
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neutrino78x

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You don't need heavy lift if you assemble things in orbit.

--Brian
 
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neutrino78x

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RVHM":414ca7k3 said:
neutrino78x":414ca7k3 said:
You don't need heavy lift if you assemble things in orbit.

--Brian
It drives LOM numbers right up.
I would rather design capsules that can lift people into LEO using commercial rockets, and lift the BEO craft in modules using other commercial rocket launches, and link them in space. That's assuming my budget doesn't allow me to make reusable launch vehicles. But if I have a small budget, I should spend it on the BEO vehicle itself, and buy launch services from American companies that routinely launch satellites.

--Brian
 
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oldAtlas_Eguy

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If you don't have a goal that requires 100+MT lift capability, getting NASA funded to build one to have it sitting on shelf is just not going to happen. Shuttle almost didn't happen. Its original goal was to construct and service a massive space station. But Congress wouldn'pay for development of both at the same time so NASA had to sell Shuttle on its secondary uses to get it built. It still wasn't enough which is why we ended up with the design we have, low developemnt cost high operational cost.

With the "back to the moon" we had a goal and imediate requirement for a 100+MT booster. When the goal was deleted so went the booster.

Commercial will not develop a 100+MT booster unless someone is going to use it and they have firm contracts for it. SpaceX and Lockheed-Martin have designs for 30MT boosters but until there is a customer they won't even start actual development on them. In both cases design is 95% complete because it was designed in the basic core design. But until there is a customer that last 5% is as good as requiring a 100%.
 
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neutrino78x

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oldAtlas_Eguy":2er602cw said:
If you don't have a goal that requires 100+MT lift capability, getting NASA funded to build one to have it sitting on shelf is just not going to happen.
I would argue there is no such goal. You have to design your projects in such a way that the modules can be lifted with commercial launch services, including the human capsules. Send everything to LEO, assemble it there. Don't send the humans up until the vehicle is assembled in orbit, that way you're not worried about it taking longer to assemble.

I think if anything, you would want heavy lift for cargo, but you wouldn't do human rated heavy lift, because the humans can go up separately and enter the vehicle in space.

--Brian
 
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oldAtlas_Eguy

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neutrino78x":2624oali said:
Send everything to LEO, assemble it there. Don't send the humans up until the vehicle is assembled in orbit, that way you're not worried about it taking longer to assemble.

I think if anything, you would want heavy lift for cargo, but you wouldn't do human rated heavy lift, because the humans can go up separately and enter the vehicle in space.
Yes! If all you need is relative cheap 30MT loads to LEO to construct whatever needed. Atlas V Heavy and Falcon 9 Heavy will do the job at $95 to $130 mil per launch. Atlas V Heavy may cost more but is listed as available now. Less than two year lead time to launch. If it was needed it could launched in 2012. Falcon 9 Heavy earliest is listed as 2013.
 
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RVHM

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Can't find a link now, but Arianespace undertook a study on going with Ariane-5 to the Moon a couple of years ago, using LEO assembly. Their conclusion was that the great number of launches required drove the LOM numbers so high that it was an impractical idea.

And that was Ariane-5, whose track record is better than that of the EELVs.
 
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oldAtlas_Eguy

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RVHM":3klf8bif said:
And that was Ariane-5, whose track record is better than that of the EELVs.
The Atlas V has had one failure and that was due to an RL10 not performing a restart to circularize to GEO after the payload had been delivered to a GTO. The Centaur is used on the Atlas V to take the payloads all the way to a final GEO orbit. To get to just LEO orbit the Centaur would fire once for an extended burn. The Atlas V 552 vehicle takes the same payload size (20MT) as the upgraded Ariane-5 for less cost: $130 million to Ariane-5's $150 million.

If the lunar mission needed 200MT at LEO. With greater than 90% launch success rate that would be 10 launches with one loss you would need only one replacement launch, an additional $150 million. Total Launch costs $1.65 billion. If you used an HLV (100+MT) to lift all the weight in 2 launches at $500 million each but had to schedule at least one more to cover one of them having a launch failure the Total cost is still $1.5 billion.

Projects that have multiple launches with no unique hardware to any one launch are easier to plan for launch failures. The problem comes in when each of the 10 launches would be carrying unique hardware. You would need two of everything in order to meet schedules. Basicly the next mission hardware set would have to be in storage b y the time you launch the current.
 
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RVHM

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oldAtlas_Eguy":3utsdc1r said:
The Atlas V has had one failure and that was due to an RL10 not performing a restart to circularize to GEO after the payload had been delivered to a GTO. The Centaur is used on the Atlas V to take the payloads all the way to a final GEO orbit. To get to just LEO orbit the Centaur would fire once for an extended burn. The Atlas V 552 vehicle takes the same payload size (20MT) as the upgraded Ariane-5 for less cost: $130 million to Ariane-5's $150 million.
What has price got to do with all this? The problem is that multiple launches increase the LOM numbers, whether launches cost 100 million or 150 million.

oldAtlas_Eguy":3utsdc1r said:
If the lunar mission needed 200MT at LEO. With greater than 90% launch success rate that would be 10 launches with one loss you would need only one replacement launch, an additional $150 million. Total Launch costs $1.65 billion. If you used an HLV (100+MT) to lift all the weight in 2 launches at $500 million each but had to schedule at least one more to cover one of them having a launch failure the Total cost is still $1.5 billion.
One replacement launch and the loss of the payload. Lunar landers, etc. don't come for free. With a bigger vehicle, you have to schedule ONE more rocket to cover failures. With smaller vehicles, you have to schedule six or seven.

oldAtlas_Eguy":3utsdc1r said:
Projects that have multiple launches with no unique hardware to any one launch are easier to plan for launch failures. The problem comes in when each of the 10 launches would be carrying unique hardware. You would need two of everything in order to meet schedules. Basicly the next mission hardware set would have to be in storage b y the time you launch the current.
Impractical.
 
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oldAtlas_Eguy

Guest
RVHM":xynivfnp said:
oldAtlas_Eguy":xynivfnp said:
The Atlas V has had one failure and that was due to an RL10 not performing a restart to circularize to GEO after the payload had been delivered to a GTO. The Centaur is used on the Atlas V to take the payloads all the way to a final GEO orbit. To get to just LEO orbit the Centaur would fire once for an extended burn. The Atlas V 552 vehicle takes the same payload size (20MT) as the upgraded Ariane-5 for less cost: $130 million to Ariane-5's $150 million.
What has price got to do with all this? The problem is that multiple launches increase the LOM numbers, whether launches cost 100 million or 150 million.

oldAtlas_Eguy":xynivfnp said:
If the lunar mission needed 200MT at LEO. With greater than 90% launch success rate that would be 10 launches with one loss you would need only one replacement launch, an additional $150 million. Total Launch costs $1.65 billion. If you used an HLV (100+MT) to lift all the weight in 2 launches at $500 million each but had to schedule at least one more to cover one of them having a launch failure the Total cost is still $1.5 billion.
One replacement launch and the loss of the payload. Lunar landers, etc. don't come for free. With a bigger vehicle, you have to schedule ONE more rocket to cover failures. With smaller vehicles, you have to schedule six or seven.

oldAtlas_Eguy":xynivfnp said:
Projects that have multiple launches with no unique hardware to any one launch are easier to plan for launch failures. The problem comes in when each of the 10 launches would be carrying unique hardware. You would need two of everything in order to meet schedules. Basicly the next mission hardware set would have to be in storage b y the time you launch the current.
Impractical.
http://www.flightglobal.com/blogs/hyperbola/2008/09/european-lunar-architecture-de.html

This article shows that the LOM numbers would be better when the number launches increase not decrease.
 
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vulture4

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Have any stages other than the Atlas and Centaur used a steel balloon tank primary structure? It seems to me that everything since has used aluminum isogrid, even the Atlas V first stage. I wonder which is more cost effective, even if there wasn't a weight advantage?
 
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RVHM

Guest
oldAtlas_Eguy":201ls2jx said:
http://www.flightglobal.com/blogs/hyperbola/2008/09/european-lunar-architecture-de.html

This article shows that the LOM numbers would be better when the number launches increase not decrease.
False.

1.- Neither the article nor the EADS Astrium presentation support your claim, for which you lack any authoritative reference. You are just referring to a comment posted by someone.

2.- That someone is Gaetano Morano, often nicknamed "Morano" in spaceflight forums. As defined in another comment posted on that article, "You should not let Gaetano Marano post on your Blog, he is a world class troll who has been banned from a lot of boards... He likes to pretend he has invented many things and was robbed (google lunar x-prize, DIRECT and now Astrium's concept). Do a little search on Google, you will see..."

Marano just speaks crap.
 
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MeteorWayne

Guest
MOD HAT ON****

Let's not discuss bloggers or posters at other boards, nor refer to their blogs/posts. That IS against the rules here at SDC.

PLEASE read the Community Guidelines.

Meteor Wayne
 
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EarthlingX

Guest
A couple of more direct links :

http://www.esa.int : ESA - European Interests in Space Exploration

This is also an interesting reading :
http://www.esa.int : Reference Architecture

and :
The Exploration Architecture Trade report (pdf)
outlines the different trades and options studied during the definition of the integrated Reference Architecture for Exploration. It clarifies the design choices made and summarizes impacts on elements and architecture for the respective solutions.
No HLV, or at least not above 50t to LEO, in short.
 
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RVHM

Guest
Since they don't have a HLV, it's not like they have a choice either. In the presentation linked to in another post above, Arianespace suggested upgrading Ariane to loft 50 tonnes to LEO, by putting 6 SRBs and 2 Vulcain uppert stage engines. They would certainly upgraded it even more if it were possible.
 
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EarthlingX

Guest
RVHM":1bzb2eq3 said:
Since they don't have a HLV, it's not like they have a choice either. In the presentation linked to in another post above, Arianespace suggested upgrading Ariane to loft 50 tonnes to LEO, by putting 6 SRBs and 2 Vulcain uppert stage engines. They would certainly upgraded it even more if it were possible.
They would, if they would need to. They don't need to, they don't.

50t launcher would be needed if all launches would be from the same pad, and if there would be no fuel transfer capability, and if international cooperation would not be possible.

No need for 50t launcher, more in a nice to have category.
 
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RVHM

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EarthlingX":17zwaa29 said:
They would, if they would need to. They don't need to, they don't.
In their presentation, they state clearly that they would need to if they were to undertake a lunar mission. The fact that they max out Ariane 5 possibilities with six SRB's and two upper stage engines makes me think that they would go for an even higher tonnage if it was possible to do so.

EarthlingX":17zwaa29 said:
50t launcher would be needed if all launches would be from the same pad, and if there would be no fuel transfer capability, and if international cooperation would not be possible
You can do it that way, of course. It's just less efficient and riskier.
 
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EarthlingX

Guest
RVHM":ga0mj6yy said:
EarthlingX":ga0mj6yy said:
They would, if they would need to. They don't need to, they don't.
In their presentation, they state clearly that they would need to if they were to undertake a lunar mission. The fact that they max out Ariane 5 possibilities with six SRB's and two upper stage engines makes me think that they would go for an even higher tonnage if it was possible to do so.
It's what makes sense, given what they have. Yea, it would be nice to have Enterprise NGC-1701C too, but ..

RVHM":ga0mj6yy said:
EarthlingX":ga0mj6yy said:
50t launcher would be needed if all launches would be from the same pad, and if there would be no fuel transfer capability, and if international cooperation would not be possible
You can do it that way, of course. It's just less efficient and riskier.
More efficient and less riskier with new untested rocket for which there is no money and no market demand ? How did you get to that ?

How many 20t launches were this year in USA, not counting STS ?
 
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RVHM

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EarthlingX":2vq41obd said:
It's what makes sense, given what they have. Yea, it would be nice to have Enterprise NGC-1701C too, but ..
But why would they want to use (for example) three 50-tonne launches instead of eight 20-tonne launches? If orbital assembly is such a piece of cake and LOM don't rise, they surely would prefer not to stick more SRB's to the existing Ariane. Tell me then, why do they propose upgrading Ariane instead of making do with what they have?

EarthlingX":2vq41obd said:
More efficient and less riskier with new untested rocket for which there is no money and no market demand ? How did you get to that ?

How many 20t launches were this year in USA, not counting STS ?
Yes, once the "untested" rocket has been tested, it will be less risky in the long run. The EELV's were also "untested" at the beginning, yet they were designed, built and flown and now they are very useful.
 
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rockett

Guest
What's amazing to me, is that we are ONLY talking about "re-inventing" the Saturn V here (in a manner of speaking), yet it has sparked a tremendous amount of debate about whether or not we should. We, the space enthusiast community, of all people, should be thinking BIG, with an optimistic view of where we can go!

If you REALLY want something to think about, how about the NOVA series from the sixties? Up to 330 mt lift capacity?
http://en.wikipedia.org/wiki/Nova_(rocket)
 
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