Author Topic: Exploration Enterprise Workshop Day 1 and Day 2 Presentations released  (Read 18821 times)

Offline 2552

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http://www.nasa.gov/home/hqnews/2010/may/HQ_M10-081_Exploration_Charts.html

Quote
NASA Announces Posting Of Space Exploration Workshop Charts

WASHINGTON -- Presentation charts for the opening-day briefings of NASA's Exploration Enterprise Workshop in Galveston, Texas, will be posted online at noon EDT, Monday, May 24.

The two-day workshop brings together a broad community of space exploration stakeholders from government, industry and academia. The Exploration Systems Mission Directorate's plans for human and robotic space exploration and the administration's fiscal year 2011 budget request for the agency will be discussed.

Presentations:
http://www.nasa.gov/exploration/new_space_enterprise/home/workshop_home.html

Edit: day 2 presentations released
Edit: Videos of the Day 1 presentations and Panel Q&A are up.
« Last Edit: 07/14/2010 07:56 AM by 2552 »

Offline Namechange User

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My favorite parts are the disclaimers.
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Offline 2552

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Page 8 of the Heavy Lift presentation has 6 thumbnails of notional new HLVs. The 2nd, 3rd, and 4th (HLV 4's core stage looks slightly wider than the boosters) 5th are common core designs, similar to Atlas V Phase 2/3. Interesting.

Edit: Looking closer (zoomed in), it looks like HLVs 1, 2, and 3 use winged flyback boosters. HLV 4 does not, and looks the most similar to Atlas V Phase 2.

Edit: Page 11 mentions a partially reusable HLV as a possibility:
Quote
The study shall identify and analyze multiple alternative architectures (expendable, reusable, or some combination) on which a Heavy Lift System addressing the objectives can be based

This would seem to make an RS-84-derived engine design a bit more likely.

« Last Edit: 05/24/2010 10:44 PM by 2552 »

Offline neilh

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Awesome, thanks for posting this. There's a lot of really interesting info.
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Offline neilh

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My favorite parts are the disclaimers.

How so?
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Offline stealthyplains

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Page 8 of the Heavy Lift presentation has 6 thumbnails of notional new HLVs. The 2nd, 3rd, and 4th are common core designs, similar to Atlas V Phase 2. Interesting.

#6 is the draft BAA six-LOX/RP mega-Saturn.

Offline Jorge

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My favorite parts are the disclaimers.

How so?

"In fact, not all proposed missions and investments fit the in
budget at this time."

Grammar aside, this is actually reasonable, though I consider it quite likely that the disclaimer will be conveniently ignored by some FY11 budget proponents when it suits their aims. ("But look at all this neat stuff we can afford if Constellation is cancelled! In-orbit propellant transfer and storage! Lightweight/inflatable modules! Automated/autonomous rendezvous and docking! Aero-assist/entry, descent and landing! Closed loop life support! Advanced in-space propulsion (ion/plasma, etc)!")

When in reality, the actual budget will only support a few of those.
JRF

Offline renclod

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My favorite parts are the disclaimers.

Also: what Jorge said.

"Proposed missions and investments do not necessarily all fit in budget at this time
...
Specific launch dates and missions are likely to change
...
Proposal must (and will) fit within NASA’s space flight budget profile
..."




Offline neilh

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My favorite parts are the disclaimers.

How so?

"In fact, not all proposed missions and investments fit the in
budget at this time."

Grammar aside, this is actually reasonable, though I consider it quite likely that the disclaimer will be conveniently ignored by some FY11 budget proponents when it suits their aims. ("But look at all this neat stuff we can afford if Constellation is cancelled! In-orbit propellant transfer and storage! Lightweight/inflatable modules! Automated/autonomous rendezvous and docking! Aero-assist/entry, descent and landing! Closed loop life support! Advanced in-space propulsion (ion/plasma, etc)!")

When in reality, the actual budget will only support a few of those.

The items you listed (inflatable modules, propellant transfer, ARRD, aero-assist, ECLLS, advanced ion propulsion) all fall under the initial set of ETDD and FTD missions, which already have funding allocated for them in the budget: http://www.nasa.gov/news/budget/index.html

The disclaimer is likely for follow-up missions/demonstrations missions which aren't already in the budget (e.g. multi-megawatt NEP, 23m inflatable decelerator at Mars, nuclear thermal propulsion, EVA tech, Mars medical suite demo, in-space VASIMR demo, building mega-Saturn and other HLLV construction), which will likely be prioritized on the basis of results from earlier missions/demonstrations.

Of course, I suspect that won't stop anti-FY2011 folks from falsely claiming that it can't afford its initial missions and tech demonstrations.
« Last Edit: 05/24/2010 09:52 PM by neilh »
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Offline Namechange User

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My favorite parts are the disclaimers.

How so?

"In fact, not all proposed missions and investments fit the in
budget at this time."

Grammar aside, this is actually reasonable, though I consider it quite likely that the disclaimer will be conveniently ignored by some FY11 budget proponents when it suits their aims. ("But look at all this neat stuff we can afford if Constellation is cancelled! In-orbit propellant transfer and storage! Lightweight/inflatable modules! Automated/autonomous rendezvous and docking! Aero-assist/entry, descent and landing! Closed loop life support! Advanced in-space propulsion (ion/plasma, etc)!")

When in reality, the actual budget will only support a few of those.

The items you listed (inflatable modules, propellant transfer, ARRD, aero-assist, ECLLS, advanced ion propulsion) all fall under the initial set of ETDD and FTD missions, which already have funding allocated for them in the budget: http://www.nasa.gov/news/budget/index.html

The disclaimer is likely for follow-up missions/demonstrations missions which aren't already in the budget (e.g. multi-megawatt NEP, 23m inflatable decelerator at Mars, nuclear thermal propulsion, EVA tech, Mars medical suite demo, in-space VASIMR demo, building mega-Saturn and other HLLV construction), which will likely be prioritized on the basis of results from earlier missions/demonstrations.

Of course, I suspect that won't stop anti-FY2011 folks from falsely claiming that it can't afford its initial missions and tech demonstrations.

No, that is not what the disclaimer is for.  It applies to every single piece.  It says missions, concepts, timelines, etc are subject to change.

As for what you specifically point one, none of them have any funding.  The reason is because there is no budget for anything yet and that is the plain and simple truth.
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Offline neilh

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As for what you specifically point one, none of them have any funding.  The reason is because there is no budget for anything yet and that is the plain and simple truth.

I'm sorry, but isn't this logic somewhat circuitous?

Anyways, we should probably bring this thread back to discussing the actual contents of the workshop presentation.
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Offline Namechange User

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I'd also like to point out that many of the items proposed in FY2011 have been worked in the past or are being worked.  I point this out because I believe too many think that these are brand new or impossible to work with a more focused program.  That is simply not the case. 

For example I will point out the following:

1.  Inflatable modules?  The Bigelow designs are based off NASA's TransHab, which saw actual testing.

2.  VASMIR?  Funded by JSC prior Dr. Diaz forming his own company.

3.  Lox/Methane engines?  Fired at WSTF and funded by NASA.  The most recent was a few weeks ago.  http://www.aerojet.com/news2.php?action=fullnews&id=221

4.  Prop transfer?  Hypergolic transfer from the orbiter to the ISS was near ready to be implemented (on the orbiter) nearly a decade ago until the ISS prop module was cancelled.  Testing had been completed at WSTF and the design was through CDR (I believe anyway, it was a while ago).

5.  Inflatable aeroshells?  Langley just completed a sub-orbital test launch a few months ago.

I could go on but I thought it was time to bring this up.  It simply does not have to be as black and white or binary as some, mainly pro-FY2011 supporters suggest unfortunately.  That doesn't mean there will always be money for everthing but as has been stated the FY2011 proposals cited on this thread clearly say the same thing. 

In fact, TransHab was near cancellation but it was transferred to Bigelow and a whole new company was formed.  As for VASMIR, it was difficult for JSC to fund and another company was formed.  This is what NASA is supposed to do and it did it without sacraficing everything else. 
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Offline kraisee

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Agreed, OV.

There are a lot of people who are trying to make the argument that we need to abandon the whole of NASA's >$5bn HSF efforts (ISS independent) in order to make room for less than $1.5bn worth of new R&D and Commercial spaceflight combined.

I'm just not buying what they're selling.

Ross.
« Last Edit: 05/24/2010 10:26 PM by kraisee »
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Offline Seattle Dave

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I've got a proposal that will cost nothing in dev costs and can lift 65,000lbs, astronauts and bring back downmass. It can also support EVAs for assembly of hardware on orbit, and is reusable.

It's a bit expensive to run, but the workforce is trained and seasoned, and we'll be ready for operational missions of your choosing in 2010.

Offline neilh

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I'd also like to point out that many of the items proposed in FY2011 have been worked in the past or are being worked.  I point this out because I believe too many think that these are brand new or impossible to work with a more focused program.  That is simply not the case. 

For example I will point out the following:

1.  Inflatable modules?  The Bigelow designs are based off NASA's TransHab, which saw actual testing.

2.  VASMIR?  Funded by JSC prior Dr. Diaz forming his own company.

3.  Lox/Methane engines?  Fired at WSTF and funded by NASA.  The most recent was a few weeks ago.  http://www.aerojet.com/news2.php?action=fullnews&id=221

4.  Prop transfer?  Hypergolic transfer from the orbiter to the ISS was near ready to be implemented (on the orbiter) nearly a decade ago until the ISS prop module was cancelled.  Testing had been completed at WSTF and the design was through CDR (I believe anyway, it was a while ago).

5.  Inflatable aeroshells?  Langley just completed a sub-orbital test launch a few months ago.

I could go on but I thought it was time to bring this up.  It simply does not have to be as black and white or binary as some, mainly pro-FY2011 supporters suggest unfortunately.  That doesn't mean there will always be money for everthing but as has been stated the FY2011 proposals cited on this thread clearly say the same thing. 

In fact, TransHab was near cancellation but it was transferred to Bigelow and a whole new company was formed.  As for VASMIR, it was difficult for JSC to fund and another company was formed.  This is what NASA is supposed to do and it did it without sacraficing everything else. 

Correct. The point of FY2011's tech development efforts isn't to somehow take completely new TRL1 technology and somehow stick it into TRL8 missions, but rather continually develop and test various types of technology and push it up the TRL stack. The attached image, taken from this presentation from today's meeting illustrates the approach well.

The technologies you listed all have mid-level or mid-high TRLs, but have yet to be matured to the point that they can be tested in space and used in operational missions. That is what FY2011 seeks to do. It's also worth noting that none of the items you listed were pursued under CxP.
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Offline Namechange User

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I've got a proposal that will cost nothing in dev costs and can lift 65,000lbs, astronauts and bring back downmass. It can also support EVAs for assembly of hardware on orbit, and is reusable.

It's a bit expensive to run, but the workforce is trained and seasoned, and we'll be ready for operational missions of your choosing in 2010.

Wow, that sounds great.  If only it could be true and we could have something like that.  If there were possibilities and proposals to make it less expensive too....well that would be something really special.  ;)
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Offline renclod

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from 457442main_EEWS_CommercialCrew.pdf

OK then, commercial crew to ISS conops:

"Commercial providers will generally be responsible for all management, engineering, production, logistics, testing and verification, launch preparations, mission planning, integration, training, and operational functions

Commercial providers will generally be responsible for all facilities and infrastructure;

Commercial providers will be responsible for providing Certification of Flight Readiness (CoFR) for the vehicle and all ground and flight support infrastructure to NASA for acceptance "


This here is definitely the LEO taxi model, not the crew vehicle leasing model (Boeing/Bolden) , IMO.


Offline Namechange User

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I'd also like to point out that many of the items proposed in FY2011 have been worked in the past or are being worked.  I point this out because I believe too many think that these are brand new or impossible to work with a more focused program.  That is simply not the case. 

For example I will point out the following:

1.  Inflatable modules?  The Bigelow designs are based off NASA's TransHab, which saw actual testing.

2.  VASMIR?  Funded by JSC prior Dr. Diaz forming his own company.

3.  Lox/Methane engines?  Fired at WSTF and funded by NASA.  The most recent was a few weeks ago.  http://www.aerojet.com/news2.php?action=fullnews&id=221

4.  Prop transfer?  Hypergolic transfer from the orbiter to the ISS was near ready to be implemented (on the orbiter) nearly a decade ago until the ISS prop module was cancelled.  Testing had been completed at WSTF and the design was through CDR (I believe anyway, it was a while ago).

5.  Inflatable aeroshells?  Langley just completed a sub-orbital test launch a few months ago.

I could go on but I thought it was time to bring this up.  It simply does not have to be as black and white or binary as some, mainly pro-FY2011 supporters suggest unfortunately.  That doesn't mean there will always be money for everthing but as has been stated the FY2011 proposals cited on this thread clearly say the same thing. 

In fact, TransHab was near cancellation but it was transferred to Bigelow and a whole new company was formed.  As for VASMIR, it was difficult for JSC to fund and another company was formed.  This is what NASA is supposed to do and it did it without sacraficing everything else. 

Correct. The point of FY2011's tech development efforts isn't to somehow take completely new TRL1 technology and somehow stick it into TRL8 missions, but rather continually develop and test various types of technology and push it up the TRL stack. The attached image, taken from this presentation from today's meeting illustrates the approach well.

The technologies you listed all have mid-level or mid-high TRLs, but have yet to be matured to the point that they can be tested in space and used in operational missions. That is what FY2011 seeks to do. It's also worth noting that none of the items you listed were pursued under CxP.

Well, you do know best and all I'm sure.  Yet I will point out the following:

1.  One of these were funded under the Exploration Technology Development Program.  What's that you ask?  I'll leave it to the "experts".

2.  All of them occurred while at least two active programs were in play. 

3.  Given that, there is nothing to say they cannot continued to be matured to get the TRL up or turn them over to, dare I say it, wait for it...wait for it...a commercial company.  What?  Are you kidding me?

But what do I know, I just work in this business.....
« Last Edit: 05/24/2010 10:46 PM by OV-106 »
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Offline neilh

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1.  One of these were funded under the Exploration Technology Development Program.  What's that you ask?  I'll leave it to the "experts".

My mistake, I had forgotten about the LOX/methane work ETDP did with XCOR and Armadillo.
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Offline Namechange User

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1.  One of these were funded under the Exploration Technology Development Program.  What's that you ask?  I'll leave it to the "experts".

My mistake, I had forgotten about the LOX/methane work ETDP did with XCOR and Armadillo.

Yeah, it was very limited clearly.

http://www.nasa.gov/directorates/esmd/aboutesmd/acd/technology_dev.html

Look, why I never agreed with the implementation of the CxP launch vehicles, the INTENT was to make it as simple as possible so that we could actually DO something somewhere else and not spend all the money getting off Earth.  Clearly things went wrong there but nothing that could not be refocused. 

It's time people realized the truth. 
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Offline RyanC

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I love the HLV Vehicle paper --

Quote
R&D on First Stage Launch Propulsion

Large hydrocarbon (liquid oxygen/kerosene) engine capable of generating high levels of thrust exceeding roughly one million pounds of thrust at sea level. Improved robustness, efficiencies, affordability, operability

– Explore partnership with DoD – common engine for national security and civil space missions

– Goal: Fully operational engine by 2020

Didn't we get RS-84 near flight testing before it was cancelled in what 2003?

So what's with the decade long delay before we can get RS-84 (plus)?

Offline neilh

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The 2015 lunar precursor is quite interesting, although I'm a little dismayed that Project M (humanoid robot on the Moon by December 2012) isn't in the current presentations; I'm guessing most of the Project M elements are being used for the 2015 mission instead. I came across a white paper from May 3, 2010 on Project M, which seemed somewhat promising:

http://robonaut.jsc.nasa.gov/m-whitepaper.asp
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Offline Ronsmytheiii

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I don't see the point in using flyback kerolox boosters, seem like a huge upfront development cost for at most marginal cost savings, unless the boosters are the core for the USAF partially reusable study LV.

is it me or does this entire plan sound like SLI part II?
« Last Edit: 05/25/2010 12:27 AM by Ronsmytheiii »
And this is a good reminder that just because one of your fellow space enthusiasts occasionally voices doubts about the SpaceX schedule announcements or is cautious about believing SpaceX has licked a problem before actually seeing proof that's true, it doesn't mean they hate SpaceX.

Offline alexw

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I'd also like to point out that many of the items proposed in FY2011 have been worked in the past or are being worked.  I point this out because I believe too many think that these are brand new or impossible to work with a more focused program.  That is simply not the case. 
     Isn't the key difference that this plan budgets and schedules to actually launch missions, with actual in-space hardware, on actual launch vehicles?
    The whole point is that this technology has been "worked in the past" (as you say), in the lab and ground-tests, but there was little or no allocated money or plan to actually fly. Before now.
-Alex

Offline Namechange User

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I'd also like to point out that many of the items proposed in FY2011 have been worked in the past or are being worked.  I point this out because I believe too many think that these are brand new or impossible to work with a more focused program.  That is simply not the case. 
     Isn't the key difference that this plan budgets and schedules to actually launch missions, with actual in-space hardware, on actual launch vehicles?
    The whole point is that this technology has been "worked in the past" (as you say), in the lab and ground-tests, but there was little or no allocated money or plan to actually fly. Before now.
-Alex

Prove to me any of this will actually fly. 

After all, if it so "game-changing", etc then that also means that still some more work needs to be done in order to get it to fly.  Now, as I stated, I have no problem working some of this stuff and have no delusions that we can do significant exploration without it.  However, note I said "significant" because we can do some exploration with what we have now and continue to mature other technologies.

The problem with die-hard supporters of FY2011 is that the wool is being pulled over your collective eyes.  Some fancy buzz words are thrown around to make it sound great but many of the details are missing, and like I said, it is completely possible to work some of these under a more focused program.  In addition, NASA's history is rittled with programs that were intended to fly and never did.  I could name them but it would be a long list.  The FY2011 proposals will be the latest, and possibly last, addition. 

Only if one wanted to not do something would one pursue this path where everything is stopped, excuses are made that we simply cannot do it with our current state of technology and decisions are deferred and notional missions do not start for another 15 years. 
« Last Edit: 05/25/2010 02:25 PM by OV-106 »
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Offline FinalFrontier

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I'd also like to point out that many of the items proposed in FY2011 have been worked in the past or are being worked.  I point this out because I believe too many think that these are brand new or impossible to work with a more focused program.  That is simply not the case. 
     Isn't the key difference that this plan budgets and schedules to actually launch missions, with actual in-space hardware, on actual launch vehicles?
    The whole point is that this technology has been "worked in the past" (as you say), in the lab and ground-tests, but there was little or no allocated money or plan to actually fly. Before now.
-Alex

Hate to break it to you but, STS has been "launching missions" for years if I recall. Oh and BTW you could do this stuff and still have SDHLV easily, with proper budgeting and managment (something NASA lacks at the moment). And you could fly heavier tech demonstraters on HLV (if need be).
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Offline alexw

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Hate to break it to you but, STS has been "launching missions" for years if I recall.
    We are discussing BEO technology hardware and demonstration missions in this thread, not doing laps in LEO. STS is not (did not become) a relevant BEO launcher.
Quote
Oh and BTW you could do this stuff and still have SDHLV easily, with proper budgeting and managment (something NASA lacks at the moment).
      That's nice to say, but show your numbers. DIRECT's alternative budget is a reasonable starting point, but even it does not do "all of this stuff". SDHLV means means mission hardware cuts.
Quote
And you could fly heavier tech demonstraters on HLV (if need be).
    Sure. And ponies, too.
-Alex

Offline alexw

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Prove to me any of this will actually fly. 

After all, if it so "game-changing", etc then that also means that still some more work needs to be done in order to get it to fly.  Now, as I stated, I have no problem working some of this stuff and have no delusions that we can do significant exploration without it.  However, note I said "significant" because we can do some exploration with what we have now and continue to mature other technologies.
     "Prove it"?  Obviously you know that's nonsensical.

     It's true, we could do (some) exploration without any of this. If the old plans were credible, we could have put men on Mars /w Apollo-tech (and 10% of the US GDP?...)  But we need to raise the mission benefit/cost ratio, in order to get Congress to fund them. And I share your interest in doing near-term exploration pending better tech, but it would seem that most of that would require nontrivial SDHLV spending, necessarily starving at least some of the tech flight missions.

Quote
The problem with die-hard supporters of FY2011 is that the wool is being pulled over your collective eyes.  Some fancy buzz words are thrown around to make it sound great but many of the details are missing, and like I said, it is completely possible to work some of these under a more focused program.  In addition, NASA's history is rittled with programs that were intended to fly and never did.  I could name them but it would be a long list.  The FY2011 proposals will be the latest, and possibly last, addition. 
      I'm listening hard -- I respect that you've been in the business a long time. Can you be more specific about your warnings in the first two sentences? And I hope that everyone here is well versed in cancelled NASA missions; do you have some specific past tragedies in mind that closely parallel these "Exploration Enterprise" Proposals? Lastly, what do you mean by a more "focused" program -- which of these proposed missions would you choose to cut?

Quote
Only if one wanted to not do something would one pursue this path where everything is stopped, excuses are made that we simply cannot do it with our current state of technology and decisions are deferred and notional missions do not start for another 15 years. 
     As I understand it, even if we develop J-130, the only non-notional BEO mission we can definitely fly this decade is Orion-around-the-moon (using DIVHUS), which doesn't seem spectacularly worthwhile in itself. Perhaps we can also fly a NEO rendezvous, but JUS and a hab module will take even more from these FY2011 proposals. What do you want to fly sooner than 15 years, and what (keeping this thread on track) do you want to cut?

-Alex

Offline neilh

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Any chance we could get some discussion of the actual workshop presentations in this thread?
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Offline kkattula

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     Isn't the key difference that this plan budgets and schedules to actually launch missions, with actual in-space hardware, on actual launch vehicles?
    The whole point is that this technology has been "worked in the past" (as you say), in the lab and ground-tests, but there was little or no allocated money or plan to actually fly. Before now.
-Alex

You're kidding right?  One (less than 60 kg) robot to the moon in 2015 and a robot on the ISS are the only actual flights listed. Everything else is ground test.

Is it so hard to think you could cut CxP down to a simple SD HLV plus Orion, fund a moderate CCDev program, and still afford to increase the spend on R&D? And maybe throw in a little extra in 2011-2013 to stretch the Shuttle and close the gap.


Offline neilh

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You're kidding right?  One (less than 60 kg) robot to the moon in 2015 and a robot on the ISS are the only actual flights listed. Everything else is ground test.

Huh? I think we're looking at different presentations. All of the FTD missions and robotic precursor missions are orbital or BEO flights, plus the ETDD autonomous atmospheric lander flights.
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Offline 2552

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Bump. Day 2 presentations released. Same url, below the Day 1 presentations.

http://www.nasa.gov/exploration/new_space_enterprise/home/workshop_home.html

Offline 2552

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From the CRYOSTAT presentation, page 14:
Quote
In-orbit transfer of propellants allows space vehicles to be refueled on-orbit.
–  May reduce launch vehicle weight due to P/L being flown dry or reduced prop
–  Enables commercial providers to deliver on-orbit propellants.
–  Enables on-orbit assembly, satellite servicing missions, and resupply or empty or partially filled
stages and spacecraft.

I wondered whether commercial launchers would be filling the depot, or the HLV itself would. Guess that answers that.

They also seem to be leaning towards a LOX/methane upper stage/depot (page 16).

Offline neilh

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They also seem to be leaning towards a LOX/methane upper stage/depot (page 16).

I'm not sure how much I agree with it, but here's the current rationale (presumably subject to change as the RFI proceeds) on preferring LOX/LCH4 over LOX/LH2:

http://www.nasa.gov/pdf/458814main_FTD_CRYOGENICPropellantSTorageAndTransferMission.pdf
Quote
Cryogen Options Review: Why Methane (vs. Hydrogen)
• A early LOX/Methane demo offers advantages:
– Enables methane-based systems and mitigates risks for LH2 systems.
– Allows direct comparison of active vs. passive cooling.
– Leverages recent investments in LO2/LCH4 cryo fluid management
– Leverages recent investments in pressure-fed engines
– Breaks the barrier for long-duration cryo systems.
• A LOX/Hydrogen demo in foreseeable future is possible.
– Low cryo cooler TRL implies shorter mission duration.
– No accurate gauging method for unsettled propellants.
• Due to similarity of LOX and LCH4 properties (e.g. temp, density, etc.), the same components may be qualified and used for ground test and flight hardware.
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Offline rcoppola

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Why is there no scaled up BEO "dream chaser" type spacecraft concept included to fly atop a new liquid HLV? So much legacy knowledge afer 30 years of shuttle. Certainly we can "re-imagine" a more cost effective and technically  superior RLV at this point. I feel as if it should be part of their discussion.   
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Offline 2552

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The 2nd thumbnail on page 8 of the Heavy Lift & Propulsion Technology (HL&PT) presentation shows something like that actually.

See the picture attached to this post.

Offline robertross

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Wow, I think we have our answer for the Node 1 Test article that is in the Space Station Processing facility!

On page 13 of the Inflatable Module Mission document.

Node 4 (Option).

How cool is that!

Edit to add: Unfortunately it wouldn't be via shuttle. On page 27 of the Automated Autonomous Rendezvous & Docking document, they use a 5.0m Atlas fairing to launch Node 4. Oh well, still cool.
« Last Edit: 06/03/2010 12:58 AM by robertross »
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Offline Nancyloo

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They also seem to be leaning towards a LOX/methane upper stage/depot (page 16).

I'm not sure how much I agree with it, but here's the current rationale (presumably subject to change as the RFI proceeds) on preferring LOX/LCH4 over LOX/LH2:

http://www.nasa.gov/pdf/458814main_FTD_CRYOGENICPropellantSTorageAndTransferMission.pdf
Quote
Cryogen Options Review: Why Methane (vs. Hydrogen)
• A early LOX/Methane demo offers advantages:
– Enables methane-based systems and mitigates risks for LH2 systems.
– Allows direct comparison of active vs. passive cooling.
– Leverages recent investments in LO2/LCH4 cryo fluid management
– Leverages recent investments in pressure-fed engines
– Breaks the barrier for long-duration cryo systems.
• A LOX/Hydrogen demo in foreseeable future is possible.
– Low cryo cooler TRL implies shorter mission duration.
– No accurate gauging method for unsettled propellants.
• Due to similarity of LOX and LCH4 properties (e.g. temp, density, etc.), the same components may be qualified and used for ground test and flight hardware.

I still don't follow the desires for methane.  Every EDS supporting EM-L1, LLO, NEO, LMO, Lunar surface, Mars Surface (you get the picture) is base lined to use LH2 thanks to the much higher ISP.  We also have 50 years experience with handling LH2 on orbit, with existing flight hardware but relatively little experience with methane.  So what about cryo-cooler TRL, just use passive thermal protection and deal with the modest boil-off, performance wise you are still way ahead.

Offline Nancyloo

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Prove to me any of this will actually fly. 

After all, if it so "game-changing", etc then that also means that still some more work needs to be done in order to get it to fly.  Now, as I stated, I have no problem working some of this stuff and have no delusions that we can do significant exploration without it.  However, note I said "significant" because we can do some exploration with what we have now and continue to mature other technologies.
The problem with die-hard supporters of FY2011 is that the wool is being pulled over your collective eyes.  Some fancy buzz words are thrown around to make it sound great but many of the details are missing, and like I said, it is completely possible to work some of these under a more focused program.  In addition, NASA's history is rittled with programs that were intended to fly and never did.  I could name them but it would be a long list.  The FY2011 proposals will be the latest, and possibly last, addition. 
Only if one wanted to not do something would one pursue this path where everything is stopped, excuses are made that we simply cannot do it with our current state of technology and decisions are deferred and notional missions do not start for another 15 years. 

I'm curious what you mean by your above statements?
"We can do some exploration with what we have now" 
1) Are you referring to  Shuttle?  Good luck getting beyond LEO with shuttle.
2) Ares I? We've spent $4B down this path with billions to go, no guarantees it will work and when it is finally complete it will almost achieve Delta LEO capability, but provide a fraction of Deltas TLI performance.
3) EELV? Can support crewed LEO missions, but how does EELV as is support beyond LEO?
4) Ares V?  Hasn't even really started as a design.

Offline robertross

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I still don't follow the desires for methane.  Every EDS supporting EM-L1, LLO, NEO, LMO, Lunar surface, Mars Surface (you get the picture) is base lined to use LH2 thanks to the much higher ISP.  We also have 50 years experience with handling LH2 on orbit, with existing flight hardware but relatively little experience with methane.  So what about cryo-cooler TRL, just use passive thermal protection and deal with the modest boil-off, performance wise you are still way ahead.


It's all about Mars. Using the Sabatier process, you can combine H2 & CO2 to produce methane and water: rocket fuel for the return trip & obviously drinking water (including supplies for surface stay & the return trip). So the less we rely on H2 for but the essentials, the better off we are.
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Offline pathfinder_01

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They also seem to be leaning towards a LOX/methane upper stage/depot (page 16).

I'm not sure how much I agree with it, but here's the current rationale (presumably subject to change as the RFI proceeds) on preferring LOX/LCH4 over LOX/LH2:

http://www.nasa.gov/pdf/458814main_FTD_CRYOGENICPropellantSTorageAndTransferMission.pdf
Quote
Cryogen Options Review: Why Methane (vs. Hydrogen)
• A early LOX/Methane demo offers advantages:
– Enables methane-based systems and mitigates risks for LH2 systems.
– Allows direct comparison of active vs. passive cooling.
– Leverages recent investments in LO2/LCH4 cryo fluid management
– Leverages recent investments in pressure-fed engines
– Breaks the barrier for long-duration cryo systems.
• A LOX/Hydrogen demo in foreseeable future is possible.
– Low cryo cooler TRL implies shorter mission duration.
– No accurate gauging method for unsettled propellants.
• Due to similarity of LOX and LCH4 properties (e.g. temp, density, etc.), the same components may be qualified and used for ground test and flight hardware.

I still don't follow the desires for methane.  Every EDS supporting EM-L1, LLO, NEO, LMO, Lunar surface, Mars Surface (you get the picture) is base lined to use LH2 thanks to the much higher ISP.  We also have 50 years experience with handling LH2 on orbit, with existing flight hardware but relatively little experience with methane.  So what about cryo-cooler TRL, just use passive thermal protection and deal with the modest boil-off, performance wise you are still way ahead.



It isn’t so much for EDS stages, it is more for in space propulsion in general. We know how to build LH2 rockets. However we don’t know how to build Methane ones and a methane engine could be useful for mar s landers or just a better in space propulsion system in general.

Right now we can use hypergolic for long term propulsion (i.e. propellant for missions that last months or years). However hypergolic do not deliver the same performance as cryogenics (LH2 or Methane). LH2 is the hardest propellant to store in space. They haven’t totally ruled it out, but they think that it is going to be much too hard for a quick cheap mission to advance our confidence in propellant transfer technology.

In theory a lox\methane rocket would offer better ISP than a hypergolic one. It would also give confidence to plans like Zurbin’s that require generating methane on mars. However the reality is a little murky due to the additional mass a lox methane rocket might need (insulation…although at mars distance the problem will be keeping the lox and methane from freezing in space).

« Last Edit: 06/03/2010 01:31 AM by pathfinder_01 »

Offline neilh

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It isn’t so much for EDS stages, it is more for in space propulsion in general. We know how to build LH2 rockets. However we don’t know how to build Methane ones and a methane engine could be useful for mar s landers or just a better in space propulsion system in general.

Right now we can use hypergolic for long term propulsion (i.e. propellant for missions that last months or years). However hypergolic do not deliver the same performance as cryogenics (LH2 or Methane). LH2 is the hardest propellant to store in space. They haven’t totally ruled it out, but they think that it is going to be much too hard for a quick cheap mission to advance our confidence in propellant transfer technology.

In theory a lox\methane rocket would offer better ISP than a hypergolic one. It would also give confidence to plans like Zurbin’s that require generating methane on mars. However the reality is a little murky due to the additional mass a lox methane rocket might need (insulation…although at mars distance the problem will be keeping the lox and methane from freezing in space).

If methane depots are indeed pushed, I wonder how much commonality there would be between a methane-based upper stage or EDS and their SpaceX's current kerosene-based stages. It'd be different of course, but from my outsider's perspective it seems like it'd have more in common than their Raptor LH2-based stage.
« Last Edit: 06/03/2010 03:30 AM by neilh »
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Offline Nancyloo

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We have 50 years of working with LH2 in space near zip with methane.  I believe that a LH2 depot by 2015 is far easier to develop than a methane depot as long as we don't demand zero boil-off.  The vent gas is useful for station keeping anyways.

We aren't going to Mars for a couple decades minimum.  To go to EM-L1 we need LH2 plus Orion's storable propellant  service module.  For LLO we need LH2 plus Orion's storable propellant service module.  For NEO's we need LH2 plus likely an updated Orion SM.  So that takes care of the next 15 years.  Once we start talking lunar surface, and Mars orbit the debate over the correct return propellant get's interesting, but that is further in the future and should drive the debate over the post 2015 depot demo.

As for ISRU the H2 for cracking the CO2 needs to come from somewhere. Is it from Mars water ice?  Then you have H2 and O2.  Hard to store in large quantities on the Martian surface.  It isn't clear what the Mars ascent propellants should be H2, methane, pentane, or other higher order more storable hydrocarbon.  Jumping to methane today seems a stretch.

Offline MP99

As for ISRU the H2 for cracking the CO2 needs to come from somewhere. Is it from Mars water ice?  Then you have H2 and O2.  Hard to store in large quantities on the Martian surface.  It isn't clear what the Mars ascent propellants should be H2, methane, pentane, or other higher order more storable hydrocarbon.  Jumping to methane today seems a stretch.

Carry the H2 from Earth (it's very light), then convert the H2 + atmospheric CO2 to hydrocarbon + O2.

Of course, this relies on carrying the H2 through Mars transit, but that shouldn't be a big issue in 30 years time.

The alternative is just to convert CO2 to CO + O2.

cheers, Martin
« Last Edit: 06/03/2010 01:24 PM by MP99 »

Offline isa_guy

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NASA want to develop multi-mw electric thrusters but not the power source ( nuclear or solar ) to power them quite odd dont you think so ?
« Last Edit: 06/03/2010 04:14 PM by isa_guy »

Offline Robotbeat

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NASA want to develop multi-mw electric thrusters but not the power source ( nuclear or solar ) to power them quite odd dont you think so ?
Not odd. We already have solar panels which could do the job (150-200+W/kg) and larger solar arrays using thin-film cells could be much lighter (potentially 1000W/kg or even more) but would require more money.
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Offline robertross

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NASA want to develop multi-mw electric thrusters but not the power source ( nuclear or solar ) to power them quite odd dont you think so ?
Not odd. We already have solar panels which could do the job (150-200+W/kg) and larger solar arrays using thin-film cells could be much lighter (potentially 1000W/kg or even more) but would require more money.

IIRC it was in the presentations online...Nuclear AND Advanced Solar. They even used the ISS arrays as a comparison.
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Offline robertross

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We have 50 years of working with LH2 in space near zip with methane.  I believe that a LH2 depot by 2015 is far easier to develop than a methane depot as long as we don't demand zero boil-off.  The vent gas is useful for station keeping anyways.

Nothing wrong with having something else in your back pocket anyway. We have seen, too many times, systems that could benefit from R&D started years ago.

Not dissing LH2, it's just not something I would have all the 'eggs in one basket' approach. If we solve LH2 storage as a multi-purpose propellant, that's great, but that may not help you everywhere you go.

Anyway, all this is notional at this point.
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Offline Robotbeat

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It will pretty much always be about 10 times harder to cool liquid hydrogen than liquid oxygen or methane. This is just because it simply gets less and less efficient to remove heat the colder you get.
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Offline A_M_Swallow

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NASA want to develop multi-mw electric thrusters but not the power source ( nuclear or solar ) to power them quite odd dont you think so ?

Not odd, NASA is simply letting the military pay for development of the solar arrays.

Offline Nancyloo

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It will pretty much always be about 10 times harder to cool liquid hydrogen than liquid oxygen or methane. This is just because it simply gets less and less efficient to remove heat the colder you get.

You make the assumption that one needs to actively cool the LH2.  I don't know anyone working with hydrogen that proposes that.  Hydrogen has 10 times the sensible heat capacity of oxygen and 4 times that of methane.  With an efficient thermal design the heat of vaporization and vapor cooling is sufficient for propellant depots where one uses the vented hydrogen to provide cold gas station keeping.  An actively cooled broad area system can be added to the MLI to intercept acreage heating at a moderate temperature as an added augmentation.

Offline Nancyloo

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We have 50 years of working with LH2 in space near zip with methane.  I believe that a LH2 depot by 2015 is far easier to develop than a methane depot as long as we don't demand zero boil-off.  The vent gas is useful for station keeping anyways.

Nothing wrong with having something else in your back pocket anyway. We have seen, too many times, systems that could benefit from R&D started years ago.

Not dissing LH2, it's just not something I would have all the 'eggs in one basket' approach. If we solve LH2 storage as a multi-purpose propellant, that's great, but that may not help you everywhere you go.

Anyway, all this is notional at this point.

No disagreement.  It is just an order of priorities.  We need hydrogen to go anywhere, we have the expertise, lets demonstrate it and enable a crewed lagrange mission this decade.  Methane can follow.

Offline Ronsmytheiii

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NASA want to develop multi-mw electric thrusters but not the power source ( nuclear or solar ) to power them quite odd dont you think so ?
Not odd. We already have solar panels which could do the job (150-200+W/kg) and larger solar arrays using thin-film cells could be much lighter (potentially 1000W/kg or even more) but would require more money.

Solar energy decreases massively as one moves away from the inner solar system, Nuclear does not suffer such an issue.
And this is a good reminder that just because one of your fellow space enthusiasts occasionally voices doubts about the SpaceX schedule announcements or is cautious about believing SpaceX has licked a problem before actually seeing proof that's true, it doesn't mean they hate SpaceX.

Offline A_M_Swallow

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It will pretty much always be about 10 times harder to cool liquid hydrogen than liquid oxygen or methane. This is just because it simply gets less and less efficient to remove heat the colder you get.

You make the assumption that one needs to actively cool the LH2.  I don't know anyone working with hydrogen that proposes that.  Hydrogen has 10 times the sensible heat capacity of oxygen and 4 times that of methane.  With an efficient thermal design the heat of vaporization and vapor cooling is sufficient for propellant depots where one uses the vented hydrogen to provide cold gas station keeping.  An actively cooled broad area system can be added to the MLI to intercept acreage heating at a moderate temperature as an added augmentation.


Robotbeat is making a safe assumption.  The process is starting with hydrogen gas produced by the electrolysis of liquid water.  That will require the hydrogen to be cooled by at least 250 degrees kelvin.

Heat the super cooled ice up, melt it, perform electrolysis and liquefy the oxygen and hydrogen by refrigeration - that is going to be a high energy process.  Even using heat exchangers.

Offline Nancyloo

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It will pretty much always be about 10 times harder to cool liquid hydrogen than liquid oxygen or methane. This is just because it simply gets less and less efficient to remove heat the colder you get.

You make the assumption that one needs to actively cool the LH2.  I don't know anyone working with hydrogen that proposes that.  Hydrogen has 10 times the sensible heat capacity of oxygen and 4 times that of methane.  With an efficient thermal design the heat of vaporization and vapor cooling is sufficient for propellant depots where one uses the vented hydrogen to provide cold gas station keeping.  An actively cooled broad area system can be added to the MLI to intercept acreage heating at a moderate temperature as an added augmentation.


Robotbeat is making a safe assumption.  The process is starting with hydrogen gas produced by the electrolysis of liquid water.  That will require the hydrogen to be cooled by at least 250 degrees kelvin.

Heat the super cooled ice up, melt it, perform electrolysis and liquefy the oxygen and hydrogen by refrigeration - that is going to be a high energy process.  Even using heat exchangers.

That is accomplished here on Earth.  To get people to the first Flexible path destination EM lagrange poitn you need LH2/LO2 in LEO.  The LH2 can be launched already liquified, potentially even subcooled.  No need for high power space rated cryocoolers, which don't currently exist.  What you describe is an issue years (decades) down the road with ISRU.

Offline pathfinder_01

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That is accomplished here on Earth.  To get people to the first Flexible path destination EM lagrange poitn you need LH2/LO2 in LEO.  The LH2 can be launched already liquified, potentially even subcooled.  No need for high power space rated cryocoolers, which don't currently exist.  What you describe is an issue years (decades) down the road with ISRU.

As  it stands now LH2 is difficult to store for long periods. Meaning current upperstages can only contain enough LH2 to last for a few days not months or years. We need a cryogenic fuel that can be stored for months. Right now we lack the technology to do so. In theory LH2 storage is achievable, in reality it is harder to store than methane. NASA might change it’s mind and go for LH2 storage, but doubtful.  Methane storage helps because you can use methane for propellant instead of LH2. Lox methane should give better ISP than hypergolics. The reality is more complicated.  Hypergolic storage is known.


Offline Nancyloo

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That is accomplished here on Earth.  To get people to the first Flexible path destination EM lagrange poitn you need LH2/LO2 in LEO.  The LH2 can be launched already liquified, potentially even subcooled.  No need for high power space rated cryocoolers, which don't currently exist.  What you describe is an issue years (decades) down the road with ISRU.

As  it stands now LH2 is difficult to store for long periods. Meaning current upperstages can only contain enough LH2 to last for a few days not months or years. We need a cryogenic fuel that can be stored for months. Right now we lack the technology to do so. In theory LH2 storage is achievable, in reality it is harder to store than methane. NASA might change it’s mind and go for LH2 storage, but doubtful.  Methane storage helps because you can use methane for propellant instead of LH2. Lox methane should give better ISP than hypergolics. The reality is more complicated.  Hypergolic storage is known.



You are correct that cryo coolers are much easier at LCH4 temperatures than at LH2 temperatures.  You are also correct that it is easier to store methane with zero boil-off than LH2.

However there is no need for either of the above.  Storing LH2 with modest boil-off is not particularly hard.  This boil-off/vent GH2  is useful for station keeping anyways, so is not lost from a systems perspective.  A depot could actually vent half of the hydrogen over the course of a year and still demonstrate substantial performance benefit  over a zero boil-off methane system for even the smallest dV beyond LEO mission.

Offline Robotbeat

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Another benefit in a gravity well: methane's greater density means greater thrust for a given flowrate.

Personally, though, I think a carbon monoxide/LOX rocket for Mars makes the most sense. Use hydrolox everywhere else.
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Offline A_M_Swallow

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You are correct that cryo coolers are much easier at LCH4 temperatures than at LH2 temperatures.  You are also correct that it is easier to store methane with zero boil-off than LH2.

However there is no need for either of the above.  Storing LH2 with modest boil-off is not particularly hard.  This boil-off/vent GH2  is useful for station keeping anyways, so is not lost from a systems perspective.  A depot could actually vent half of the hydrogen over the course of a year and still demonstrate substantial performance benefit  over a zero boil-off methane system for even the smallest dV beyond LEO mission.


It is not just the depots that need zero boil off technology, the spacecraft need it as well.  In a 2 year return trip to Mars you can boil off a lot of hydrogen.  The easiest way to account for the boil off could be to treat it as an extra stage with a tiny Isp.

Offline Nancyloo

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You are correct that cryo coolers are much easier at LCH4 temperatures than at LH2 temperatures.  You are also correct that it is easier to store methane with zero boil-off than LH2.

However there is no need for either of the above.  Storing LH2 with modest boil-off is not particularly hard.  This boil-off/vent GH2  is useful for station keeping anyways, so is not lost from a systems perspective.  A depot could actually vent half of the hydrogen over the course of a year and still demonstrate substantial performance benefit  over a zero boil-off methane system for even the smallest dV beyond LEO mission.


It is not just the depots that need zero boil off technology, the spacecraft need it as well.  In a 2 year return trip to Mars you can boil off a lot of hydrogen.  The easiest way to account for the boil off could be to treat it as an extra stage with a tiny Isp.

I'm a huge fan of the evolutionary development concept.  Don't let notions of "it could be better if only" get in the way of what is possible today.  The crewed missions that are potentially going to be undertaken this decade include EM LaGrange points, low lunar orbit and maybe NEO's.  Mars and the lunar surface are out of the question in the next decade.  A cryogenic EDS coupled with a storable service module can readily support these near term mission opportunities.  Zero-boil-off may eventually have its applications but it is not necessary to get started.  Let's get operational experience with a depot and then continue to improve it.  All of the enhanced thermal protection work on a vented depots as well as the market it offers to enhance our launch capability and the prox-ops is required for zero-boil-off depots. 

Demanding zero-boil off and brand new large methane engines and in-space stages will result in Constellation like investment requirements while deferring any mission capability another decade down the road.

Offline hutchel

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On page 13 of the Inflatable Module Mission document.

Node 4 (Option).


So what are we looking at to actually develop this (time/ cost) - since there are numerous documents and comments talking about inflatable and other new ISS modules on the US side.  It's obvious that this is needed (tug and Node 4) and the HTV and ATV demonstrate it's possible but obviously they have the payloads built into the vehicles.  For the future it's obvious that this is just as important as a US human rated vehicle (capsule, etc)

Offline 2552

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Bump. Videos of the Day 1 presentations and Panel Q&A are up.
« Last Edit: 07/14/2010 07:38 AM by 2552 »

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