I missed the final, extended public meeting of the Review of US Human Space Flight Plans (aka Augustine) committee on Wednesday, unfortunately (I’m at the annual smallsat conference at Utah State University this week). So instead here’s a brief summary of the reports that came out of the hearing:
If there was a central theme, is that the money is not there to carry out the exploration program. As panel member Sally Ride put it, “We haven’t found a scenario that includes exploration that’s viable.” And committee chairman Norm Augustine: “It will be difficult with the current budget to do anything that’s terribly inspiring in the human spaceflight area.”
The committee concluded that it would take an extra $50 billion to carry out the current plan, a chunk of money that most people assume isn’t likely to materialize. One alternative under consideration is the so-called “deep space” option that would feature human missions to orbit the Moon, visit NEOs, and eventually Mars; that would cost an additional $3 billion a year. Also under consideration: extending the shuttle though 2015 as well as stretching out the current Constellation plan to fit into the budget, which would delay a human return to the Moon to the late 2020s at the earliest.
Bad news for Mars advocates is that the panel dropped a direct-to-Mars scenario from consideration. “We think Mars direct (flight) is not a mission we are prepared to take on technically or financially,” Augustine said. (This doubtless will not go over well with those Mars advocates that either distributed or endorsed this Mars Direct placard found at the previous committee meeting last week.)
Good news for commercial spaceflight advocates, though, is that “virtually every” remaining scenario includes the development of commercial human space transportation, something the Next Steps in Space coalition trumpeted in a press release Thursday. “We are confident that U.S. based commercial space companies will enhance the scientific and research capabilities of the ISS and ensure that funding now slated to go to Russia can contribute to high tech jobs here at home,” said coalition spokesman Bob Hopkins.
The Augustine committee is expected to brief NASA and the White House on its interim findings on Friday, with the final report scheduled for publication at the end of the month. In a Space News interview earlier this week, Augustine said the committee would present as many as eight options, although by the end of yesterday’s meeting there appeared to be only about four major options remaining. He emphasized that the committee will provide options, not recommendations. “We were asked to provide options and I would undermine the president’s ability to make a sound recommendation if I were to voice my opinion,” he said. “But one of the major facts being weighed is what we can afford. I just don’t have the ability to judge that.” And affordability is going to be a key issue, as it appears clear after yesterday’s meeting that the current plan, with its current schedule, is not affordable.
If you look carefully at the Deep Space options, the biggest wedge that’s driving their costs above the available budget is the development of a heavy lift vehicle, regardless of whether it’s Ares V, Shuttle side-mount, or Atlas Phase 2. Yet all the options also assume $1.5B per year of “Technology Development”, a significant portion of which would go towards development of in-space fueling capabilities from listening to the committee members, as well as a separate “In-Space Fueling” budget wedge. See:
http://www.nasa.gov/ppt/378555main_02%20-%20Sally%20Charts%20v11.ppt
It would be interesting to have Aerospace Corp. run a Deep Space scenario that assumes no heavy lift development and relies solely on in-space fueling. No doubt the “In-Space Fueling” wedge would grow a lot. But would it grow as much as the heavy lift wedges?
I also wonder what’s in the “Other Cx Elements” and “Other Non-Cx Elements”. Could those be reduced or disposed of?
FWIW…
Major Tom,
It appeared to me that there was at least one “Deep Space” scenario — as you described — that would probably fit within the budget guidance and achieve the other objectives created by the White House for the Augustine Committee.
If you take the “ISS FOCUSED” option, and eliminate the HLV launch vehicle — perhaps deferring the HLV option to later by utilizing the “commercial Hydrocarbon HLV” system and deferring the investment needed for that system down the road … the budget numbers should close.
In parallel, we then stimulate a “commercial RLV industry” to supply those orbital fuel depots, which create the large market-based demand needed to justify the investments in the RLVs.
Let the commercial RLV industry compete with commercial Super-heavy lift (EELV derived) system for propellant delivery.
The results is MUCH lower operational costs for human exploration beyond LEO.
FWIW,
– Al
Major Tom,
You can’t do that – we don’t know Prop depots. Its dangerous technnology. It adds complexity that is so difficult as to be impossible. If we put Prop depots on the cirtical path, the world will end as we know it!!!!!!
/snark
What is finally decided is not likely to be based upon what anyone here thinks is sensible. The decision of how or if we go beyond LEO will be made on the basis of what Barack Obama thinks will benefit Barack Obama.
On one extreme, Obama could decide to junk the whole exploration program. “Hey, I can be a fiscal conservative about some things. Sorry we had to do this, but it’s really all George Bush’s fault for proposing a crappy program to start with.”
On the other extreme, Obama could double down, tap the stimulus money, and go all out. “Economic stimulus! Technology! Jobs! And I’ll do it better than any of those Browshirt Nazi Republicans.”
“What is finally decided is not likely to be based upon what anyone here thinks is sensible.”
If this forum is so unimportant, why did you bother to post here?
Don’t waste your time or ours.
“Browshirt Nazi Republicans”
Ugh…
If you can’t enter a discussion without painting a entire political party as Nazis (or claiming that the President would do so) on your very first post, then you really shouldn’t be here.
Take your ugly venom elsewhere.
Bleah…
The real news seems to be that no realistic plan beyond LEO can be afforded in the current budget. (I don’t fully agree with that, and still advocate “bootstrapping” incremental missions with smaller vehicles assembled at the Space Station or elsewhere, but that’s what the commission seems to be saying.) This will put Mr. Obama in a severe bind — give up exploration altogether, which would have large political costs both internally (think Florida) and especially externally (as various Asian countries are perceived to begin to take over the lead in human spaceflight). Or, he’ll have to give up a few of his social and / or financial ambitions and come up with the money. I wonder if he already regrets establishing the commission.
All this may not get us to the moon or anywhere else, but it should result in some excellent political theater. . . .
— Donald
One other thought. Is Congress really going to sign off on abandoning human exploration in the name of universal health care (which, for the record I support) or balancing the budget? I doubt it.
— Donald
“Let the commercial RLV industry compete with commercial Super-heavy lift (EELV derived) system for propellant delivery.”
Just to be clear, I was outlining a more conservative scenario that doesn’t assume RLVs, just existing ELVs, for refueling. I don’t know if it would come out costing substantially less than HLVs, but Augustine/Aerospace should run the scenario if they havn’t. It might produce an in-budget option.
My 2 cents is that the program baseline should start from an ideal end-state, like the low operating costs that in-space fueling may offer, and put some substantial dollars into seeing if the relevant technologies/systems can be demonstrated. I’d also carry a lower level-of-effort — an HLV design in this case — as backup, and have a decision point a few years down the road between the two technical paths.
FWIW…
“You can’t do that – we don’t know Prop depots. Its dangerous technnology. It adds complexity that is so difficult as to be impossible. If we put Prop depots on the cirtical path, the world will end as we know it!!!!!!”
Joking aside, while in-space fueling may add some technological risk (depending on the version), it probably reduces budget risk. You’re really trading one type of risk for another.
FWIW…
“If you can’t enter a discussion without painting a entire political party as Nazis (or claiming that the President would do so) on your very first post, then you really shouldn’t be here.”
“Major Tom” I had no idea that you were so humor impaired.
The point I was making is the current adminustration has a tendency to blame its problems on others. It is not unique to Barack Obama, but he seems to indulge in it with greater enthusiasm than most.
The single hope that space advocates have is that Obama decides, what with health care and cap and trade cratering faster than his own poll numbers, decides to burnish himself as an agent of the future, science, technology. A reinvigorated exploration program, which would have bi partisan support in the Congress, funded with some of that stimulus money, would just about do the trick. He can even claim that VSE 2.0 would actually have an economic stimulus in certain states with large amounts of registered voters.
Major Tom — ignore the tolls.
Jeff, you said:
FOUST: Bad news for Mars advocates is that the panel dropped a direct-to-Mars scenario from consideration. “We think Mars direct (flight) is not a mission we are prepared to take on technically or financially,†Augustine said. (This doubtless will not go over well with those Mars advocates that either distributed or endorsed this Mars Direct placard found at the previous committee meeting last week.)
I wish you could have listened to the prolonged discussion of the committee. They spent a significant amount of time discussing the issue of Mars. In summary, it appears they all support Mars as the preferred destination for “expanding human civilization”, but acknowledged that the current strategy and architecture is essentially guaranteed to fail to extend human civilization to Mars. They concluded that, at best, the current technologies (and approaches) would produce a “flags & footprints” mission reminiscent of Apollo. Considering the predicted result, that we should not do that.
They then agreed that their report will state that extending human civilization to Mars is the objective of ALL the options they take to the White House, and suggest what the steps beyond the current options might look like (as an existence proof) for extending human civilization to Mars.
Therefore, based on the Augustine Committee’s stated intent to create a “realistic” (read “sustainable and affordable”) plan to set up a permanent human civilization on Mars, some Mars advocates will be happy.
FWIW,
– Al
“Is Congress really going to sign off on abandoning human exploration
Just to be clear, abandoning civil human _space flight_ is not on the table. It’s just a question of whether exploration activities beyond LEO get started sooner rather than later.
“in the name of universal health care (which, for the record I support) or balancing the budget?”
The Augustine Committee argued yesterday that NASA needs an additional $3B/yr. to get some human exploration activities underway in a reasonable timeframe.
Based on that, I’d argue that the key question is whether Congress would support a $3B/yr. increase in NASA’s budget, assuming the President did (not whether Congress would “abandon” civil human space exploration in the face of other (much larger) budget demands.)
And based on recent history, my 2 cents is that Congress won’t support such a large increase. When the VSE was rolled out, it enjoyed Presidential support and a Congress that was run by the same party as the President. In that environment, NASA received a one-time, $1B increase. And then Congress (and the President) failed to meet the original VSE budget projections every year after.
The situation is similar today, so we could maybe assume a modest, temporary increase in NASA’s budget. But I don’t think we can bet on an increase of $3B/yr.
The Augustine Committee probably needs to find an option that delivers some exploration achievements on a reasonable timeframe within the budget, or it’s just not going to happen, even with Presidential support.
FWIW…
“‘Major Tom’ I had no idea that you were so humor impaired.”
Calling other people “Nazis” is not funny.
I’m not the one whose social functions (humor or otherwise) are impaired.
“The point I was making is the current adminustration has a tendency to blame its problems on others.”
Here you go again, twice in two posts, painting thousands of people with the same broad brush strokes. And without a lick of evidence to support the statement.
Again, take your ugly venom elsewhere.
Yuck…
Thanks, Major Tom, thanks for the clarification and I don’t disagree with most of your response.
While I would prefer to see a lunar base, I also think an outcome concentrating on utilization of the ISS would not be a completely bad outcome for advocates of exploration, at least over the long term. Until orbital tourism takes off, it remains the only large market for commercial space transportation — and, in my opinion, a successful commercial space transportation industry is essential to an expansionist future. Establishing that should have a far higher priority than haring off to Mars, which, with any realistic budget, could hardly be more than a “flags and footprints” project with little or no position for the advancement of commercial space transportation in the near future.
We are also being reminded that picking a government plan and sticking to it for more than eight years is not a politically achievable goal. This is another reason to get a start on commercial space transportation via COTS-like endeavors, which, once established, could help to encourage orbital tourism as a second market. Such markets are likely to be more stable than any government project (witness the decades of consistant transportation technology supporting the comsat industry).
I’m pleased to see that COTS does seem to have a lot of supporters in the commission and is likely to be a part of several of the options. I think Mr. Obama may well like such a plan because the cost to the government would be relatively low and it could help provide political balance to his social agenda.
— Donald
Hmm Not that I want to stirr the pot a little but according to Augustine:
“He emphasized that the committee will provide options, not recommendations. “We were asked to provide options and I would undermine the president’s ability to make a sound recommendation if I were to voice my opinion,†he said. “But one of the major facts being weighed is what we can afford. I just don’t have the ability to judge that.†And affordability is going to be a key issue, as it appears clear after yesterday’s meeting that the current plan, with its current schedule, is not affordable.”
De facto or not de facto… However and a posteriori indeed some will make recommendations: OSTP + NASA Admin + OMB + Key Congress people. And the WH will decide and that will be that.
Prognostic: The result will be Deep Space followed by Mars with an opportunity in the middle for Lunar Global that will be left to the private sector (including ISS).
We shall see
“I’m pleased to see that COTS does seem to have a lot of supporters in the commission and is likely to be a part of several of the options.”
Yeah, the Augustine Committee’s emphasis on and budget allocations for commercial crew, in-space fueling, and technology generally across all of the options is probably more valuable in the long-run than any particular set of destinations. To first order, “How” is probably more important than “Where”.
FWIW…
Major Tom: To first order, “How†is probably more important than “Whereâ€.
Amen!
— Donald
Major Tom: To first order, “How†is probably more important than “Whereâ€.
On this, we fully agree!
— Donald
OMB and OSTP cut NASA’s exploration budget by billions right before they started the Augustine committee:
http://en.wikipedia.org/wiki/Review_of_United_States_Human_Space_Flight_Plans_Committee
http://www.spaceflightnow.com/news/n0905/08augustine/
The affordability of a Deep Space option without an HLV is something that really needs to be thought about. The prospect of a Deep Space effort is exciting. Propellant depoting could, in principle, get one out of that bind. With regard to such depots in the context of an associated ISS-focussed goal, it might seem (as Greason suggested in what I think he called an off-the-wall idea) that ISS is the place to put them. That strikes me as a hard choice. A large tank of high pressure fuel in the vicinity of, or even attached to station seems a big risk to a high value asset. Even putting such a tank in the same orbit as ISS would be risky. If a bad thing happened to that tank, ISS would be in the bulls eye.
So are we talking about a depot at the same inclination as ISS, but at a different altitude? How would that work?
Major Tom – I absolutely agree with you on that – in fact, thats why I helped Jon Goff with the white paper he submitted. I think the tech risk increase is very small as compared to the budget risk reduction, and would much prefer a system that has no new launcher development, and only does in space items, like prop depots, and other systems (tugs, aerobraking, and so forth)
I was merely trying to invoke the spirit of the Heavy Lift crowd (and in particular a certain A-com member)
But in reality I absolutely agree with you.
“So are we talking about a depot…”
Depending on the destination and amount of propellant required, we may not even be talking about a standing “depot” per se. It could just be a temporary, one-use, upper stage with a sunshield that tops off a mission’s transit stage. See page 5 in this presentation:
http://www.ulalaunch.com/docs/publications/PropellantDepotJPC2009.pdf
FWIW…
Doug, you bring up a very interesting point. The fact is, the ISS is not in an ideal orbit anyway — out of plane to just about anywhere interesting, I think — so put the fuel depot in another orbit. Better, have more than one.
Each fuel depot, wherever it is, is another market for COTS. . . .
— Donald
A large tank of high pressure fuel in the vicinity of, or even attached to station seems a big risk to a high value asset.
Why would it be high pressure?
Even putting such a tank in the same orbit as ISS would be risky. If a bad thing happened to that tank, ISS would be in the bulls eye.
There’s no reason to expect a propellant tank to explode. The propellants would be separated.
So are we talking about a depot at the same inclination as ISS, but at a different altitude? How would that work?
It would be at the same inclination, but it wouldn’t remain in the same orbital plane, because its node would regress at a different rate. It would have to co-orbit.
A large cryogenic tank can be quite dangerous. Fluid cryogenic propellant needn’t be high pressure at all, but you get a significant perforation in it, for example, and it can be a wild horse. It’ll quickly lose it’s radiation shield, and then pressure can build rapidly if not effectively and very carefully vented. Thereupon things can get more nasty. I’m not talking about things burning, as you seem to be assuming, but things exploding. Most space cryogenic tanks do maintain some pressure, just because you don’t want your supply being pumped on by the vacuum.
Good point about the differential node regression at different altitudes.
That ISS isn’t in an ideal orbit is a separate issue. Depends on where you want to go, and what you want to use ISS to help you with.
Most space cryogenic tanks do maintain some pressure, just because you don’t want your supply being pumped on by the vacuum.
Some pressure, but not enough to cause a catastrophic structural failure. Also, because it’s a fixed facility, and only has to be lifted once, it would be possible to build in much higher structural margins in a depot tank than (say) a launch system or transfer vehicle. Not to mention that it would have balanced overpressure vents. This is a very manageable problem, from a safety standpoint.
One could refer to the Apollo 13 oxygen tank episode. That explosion wasn’t quite catastrophic, but the big SM panel that enclosed the tanks shot off pretty fast, as probably did a goodly amount of smaller debris from the tank. Lucky there wasn’t an ISS nearby to “catch” it. The CM/SM experienced some pretty big accelerations because of the venting gas. Shook ‘em up some, and briefly lost telemetry.
Balanced overpressure vents? As in, you quickly open one up on the side opposite where you got hit? Hmmm.
Sure, you can manage the problem, but that’s not the issue. The issue is that there is increased risk that requires management. You’ve got a LOT of mechanical power stored in that tank, and wherever you have a lot of power, you have to be really careful about putting valuable things next to it. You’re also in a venue that is not very friendly to systems that you’d rather not get punctured.
BTW, a hydrogen tank would be significantly more dangerous than an oxygen tank just because of the energy of vaporization, at least per unit mass.
It is disheartening — but not surprising — to read that the Augustine Commission doesn’t see any way the current NASA budget can get us back to the Moon or to any of the spectacular alternatives that have been contemplated in anything like a reasonable time frame. That said, I agree with those that have stated that spending our time and money building the essential infrastructure — including but not limited to assembling space-based refueling depots, orbital transfer vehicles, more powerful and faster drives for manned long range missions such VASIMIR, and hopefully building a heavy lift booster — is not a bad way to spend this interregnum. Once this infrastructure is established, the cost curve of mounting manned expeditions should decline significantly (remember the biggest cost we are facing is the need to reinvent technological capabilities we had more than 40 years ago) and the probability of success should increase substantially. At least I hope it will work that way. I agree that President Obama has it in his power to throw his prestige behind a reinvigorated manned space program but, while I wish he would do that, I don’t really see that happening in the midst of the huge budget fights over economic recovery and health care reform.
According to Nature, as recently as 27th April, Mr. Obama was promising to increase national spending on R&D to three percent of GDP, which, according to the journal, would be an increase of some $46 billion per year over today’s spending of 2.7% GDP (including both public and private). If he really plans to do that, an increase to space exploration of $3 or 5 billion per year or so might not seem out of line to him. This is pure speculation, of course.
— Donald
One could refer to the Apollo 13 oxygen tank episode.
That was a result of a shorted wire. That can be designed against.
As in, you quickly open one up on the side opposite where you got hit?
No, it has nothing to do with getting hit. It’s just venting on opposite sides to result in no net thrust, in the event the pressure exceeds spec.
It’s really not as difficult as you make it to be. I could be wrong, but I’m not aware of any Centaur failure due to tank overpressurization or combustion, in hundreds of flights, and Centaur has a common bulkhead.
It is disheartening — but not surprising — to read that the Augustine Commission doesn’t see any way the current NASA budget can get us back to the Moon or to any of the spectacular alternatives that have been contemplated in anything like a reasonable time frame.
Actually, it’s not that the NASA budget can’t do it — it’s that NASA can’t do it with that budget, given its political constraints. Certainly it could be done for that amount of money, or even a lot less.
Actually, it’s not that the NASA budget can’t do it — it’s that NASA can’t do it with that budget, given its political constraints. Certainly it could be done for that amount of money, or even a lot less.
I agree, that’s the correct statement of the issue.
Mark is right in this case
We all have an interest in seeing that NASA spends it’s money as wisely as possible, and yes the Ares rockets were an amazing goof by NASA. However even absent the mistakes made by Griffin, the Augustine committee makes clear that the scheduled NASA budget is inadequate no matter which exploration option is finally taken. So the real issue is how much will Obama be willing to spend?
Considering the history of Obama’s erratic course on NASA policy combined with the currently troubled economic/political situation, I think it’s impossible to predict the outcome for NASA. In this sense Mark is right, whatever choice Obama makes will be governed more by political self-interest than the interests of space exploration. The real question is how divergent will Obama see his own interests from the interests of exploration?
However, Obama does seem to delegate policy detail to a degree I never expected, and that gives me hope. The new NASA administrator seems to want a bold program with Mars as the objective, and perhaps that is enough to persuade Obama to ask Congress for the piddling extra 3 billion/year for NASA; which is a drop in the bucket compared to the open floodgate of spending for other Obama priorities.
No, it has nothing to do with getting hit. It’s just venting on opposite sides to result in no net thrust, in the event the pressure exceeds spec.
Well, my point is that it has everything to do with getting hit. If you get a meteoroid puncture in the tank, it’s going to vent fast. On one side. You got the other side to yield no net thrust? BTW, no Centaur has been sitting around in LEO with a full tank of cryogenic propellant long enough to get hit. Bad example.
I’m not making it difficult. I’m just saying it’s a risk. If you design it so something bad will almost never happen, it’s that one time when something bad happens that there is a lot you could lose. If an isolated tanker depot gets popped, you just shrug and move on. The question is whether ISS is the right place to put such a depot that might well not need ISS for functionality.
Yes, Apollo 13 was a shorted wire. That can be designed against. In fact, as I understand it, Apollo 13 was designed against that. But it wasn’t built like it was designed.
If you get a meteoroid puncture in the tank, it’s going to vent fast. On one side. You got the other side to yield no net thrust?
That would be a function of how much control authority your RCS system has. I would assume that if it was a cryo depot, it would have gaseous LH2/LOX thrusters that could probably overcome a simple venting (again, the pressure in the tank wouldn’t be that large, and certainly a holed tank wouldn’t provide much thrust, since the jet wouldn’t even be able to hit sonic velocity). That scenario might in fact size the RCS, though reboost would be another driver, at least for LEO.
I’m just saying it’s a risk. If you design it so something bad will almost never happen, it’s that one time when something bad happens that there is a lot you could lose. If an isolated tanker depot gets popped, you just shrug and move on. The question is whether ISS is the right place to put such a depot that might well not need ISS for functionality.
I’m not proposing that it is, but not for that reason. Actually, I’d like to move ISS to a more useful location, from an exploration standpoint. Say, 28.5 degrees. But it would probably be cheaper to just use Bigelow facilities as worker habs.
In fact, as I understand it, Apollo 13 was designed against that. But it wasn’t built like it was designed.
Well, there are solutions to that as well…
I would add that if it was coorbiting a couple kilometers away, it would be close enough for maintenance purposes, but sufficiently far enough for safety.
Don’t forget that the Apollo 13 tank was dropped at the factory, too.
And does the 30-year Progress/Salyut/Mir/ISS history of propellant transfer count for anything like plowed ground for prop depot operations?
I wonder how a debris cloud would disperse if an ISS-co-orbiting platform a few kilometers away collided with something else passing by at high speed?
And does the 30-year Progress/Salyut/Mir/ISS history of propellant transfer count for anything like plowed ground for prop depot operations?
It counts for a lot, but only for hypergolics, not cryogenics.
I wonder how a debris cloud would disperse if an ISS-co-orbiting platform a few kilometers away collided with something else passing by at high speed?
It certainly wouldn’t constitute an immediate problem. Some of the pieces would deorbit fairly quickly, some would be longer lived, but move to different orbits due to nodal regression, and most would eventually be spread out into the rest of the orbital debris. The biggest pieces would be trackable, and not have that much of a differential velocity, so they could be avoided by maneuvering. But if it were seriously proposed to do this, there would be serious sims run.
and certainly a holed tank wouldn’t provide much thrust
Perhaps, if the hole is small. But thrust isn’t necessarily the relevant quantity. You’ve got an absolutely huge reservoir of propellant there, so your total momentum change can be quite awesome as it all warms up, boils away, and is ejected even with relatively low velocity. I doubt the thing is going to have thrusters that can deal with that. That’s assuming there isn’t a catastrophic event.
When the cover on WIRE was ejected prematurely the solid hydrogen vaporized quickly. Pressure in the dewar increased dramatically, and the resulting relief jet quickly put the spacecraft into a death-spin.
Perhaps a couple of kilometers is indeed a safe distance for a depot. I’m not sure. There has to be some assessment of the possible failure modes. That really has to be done before you put such a depot at a big hab site. Again, if you end up with lots of fragments in an ISS orbit it’s an unhappy situation, even if you spilled them kilometers away.
You’ve got an absolutely huge reservoir of propellant there, so your total momentum change can be quite awesome as it all warms up, boils away, and is ejected even with relatively low velocity.
You also have a huge reservoir of propellant to control the system with a much higher performance RCS.
When the cover on WIRE was ejected prematurely the solid hydrogen vaporized quickly. Pressure in the dewar increased dramatically, and the resulting relief jet quickly put the spacecraft into a death-spin.
No one is proposing solid hydrogen for propellant depots.
@Bob Mahoney:
Here I go again. I’ve said this before and I’ll say it again: hypergolics are good enough for the initial phase of an exploration effort. You would need L1 or SEL-2 staging to keep this sufficiently efficient, but that’s not a problem when you’re planning to go beyond LEO anyway. Lagrange points are such excellent staging points that the delta-v’s involved are small enough that the lower Isp is not too much of a problem. For Mars/Phobos/Deimos you could preposition propellant with SEP, thus increasing effective Isp a lot. Huntress et al proposed this as a way to avoid the use of nukes, but it even allows hypergolics.
Hypergolics have some less crucial advantages too: reliable ignition and no boil-off which is good for long duration missions far from Earth. Not crucial, but nice. The high density also helps with the capacity of the depot and makes it a smaller target for MMOD and allows for heavier shielding.
The Augustine commission has concluded the current budget does not allow exploration. In part this is because they insist on super heavy lift. Depots could avoid the need for that, and scrapping the need for HLV would make a lot of money available.
Cryogenic depots would allow exploration with existing EELVs, though you would still need some modifications to your upper stage in order to have it serve as an EDS. EELV Phase 1 (which means a new upper stage) and hypergolic depots would also allow exploration. You can even simplify it a bit further: with in-flight refueling your long distance crew shuttle can be a makeshift depot as well as a mini-space station, rescue vehicle and transfer stage. This avoids the need for development of a separate vehicle. Later on such a vehicle could also be the basis of moon and Mars landers.
Right now the commission will not consider scrapping HLV because of the alleged difficulty of cryogenic propellant transfer. Hypergolic propellant transfer and automated delivery on the other hand are very mature technologies which have seen continuous operational use for over 30 years, from Salyut-6 in 1978 to ISS today and all the Soviet/Russian stations between. Hypergolics could break the deadlock. And the commission is totally on board with research into cryogenic depots and once NASA loses heavy lift, they would want them too.
Hypergolics give us nearly all of the advantages of cryogenic depots, with the main exception of not being suitable for fueling EDSs in LEO. They are also difficult to handle, but there is plenty of experience with that. Those are good reasons to replace hypergolics in the medium term, not good reasons to spurn them in the short term.
From the point of view of stimulating the launch sector and commercial development of space in general it makes little difference what is being launched: LOX/LH2, kerosene, methane, hypergolics, water, radiation shielding panels or horse dung. As long as the cargo itself is cheap and there is a lot of it to be launched it will stimulate commercial development of space.
Wow! For once I agree with Mark Whittington! Though at least of the two scenarios he mentioned, I think the first the least likely of the two.
“You can’t do that – we don’t know Prop depots. Its dangerous technnology. It adds complexity that is so difficult as to be impossible. If we put Prop depots on the cirtical path, the world will end as we know it!!!!!!”
Knowing Ferris somewhat vicariously, I assume he is being humorous and sarcastically ironic with the above statement. But the following is for those who really don’t get it. The Apollo program took a risk on a previously untried technology called rendezvous and docking when they decided on the Command Module/LEM system even before Project Mercury was finished. The bet paid off. That technology at the time was even more risky than fuel depots are now.
No one is proposing solid hydrogen for propellant depots.
Nor did I. But you’re bringing that idea up. No one is proposing using Apollo 13 oxygen tanks for depots either, but I thought both WIRE and A13 were useful illustrations of how cryogenic reservoirs can produce some serious consequences if not managed properly.
This is getting a little silly, and oddly argumentative. I’m not suggesting that depots are a bad idea. In fact, I think they’re a fantastic idea. I’m just saying that there is some thinking beyond “Oh we can engineer that!” that can impact policy. They’re just considerations that haven’t been talked about much and, as concepts for depots are established, need to be addressed in a more than a handwaving way.
Mr. Meijering,
A simple ‘yes’ would have sufficed. But thank you for your elaboration.
One aspect of fuel depots (and any in-orbit assets) for which I see little discussion in the blogs is the restriction their locations place on launch windows, which in part reinforces the value of the L-points for such assets.
As so many of us recognize, once an intermediary destination (fuel depot, tether anchor, space assembly facility) is situated in an inclined low-earth orbit, access to that destination becomes restricted in terms of periodic timing, both from the ground and to/from lunar escape/return trajectories. Aside from pure in-plane rendezvous timing, the reality of differential nodal regression rates makes things…complicated…to be polite.
I always had a sneaking suspicion that this was one of the factors that made ESAS what it was (disposable and ground-up for each mission), sort of like a city council running away from introducing timed traffic lights because they view the very idea a bit of insurmountable complexity.
Have any folks done any substantial looks into this challenge?
ALMOST TWO YEARS AGO I WARNED YOU PEOPLE THAT THIS WAS COMING:
You people have no idea how bad things are about to become.
Word of advice: Learn demographics, and learn it now [if not, then you can just sit back and be schooled by it].
This country no longer has the demographics necessary to support a space program.
Wake up and smell the coffee.
“Obama: cut Constellation to pay for education
November 20, 2007 at 2:06 pm
spacepolitics.com”
It was revealed not long after the release of the Education Plan referred to in that article, that the part concerning the space program was inserted by an overzealous aid. In fact Obama over-ruled it long before the election with the following official space exploration policy position in early 2008.
http://www.barackobama.com/pdf/policy/Space_Fact_Sheet_FINAL.pdf
People should make sure they have their facts straight before they start accusing. Most of all we should all remember the subtitle to The Hitchhiker’s Guide to the Galaxy, “Don’t Panic!”
As for the quote:
“…The IQ Wars are upon us, folks: There are more of “them†than there are of “usâ€, and things are only going to get worse, until it all ends in disaster…”
That wasn’t from the writer of the SpaceFlight.com article. That was a blog post that you yourself made in response to that article, Vorenus. Do you realize how much of a fanatic the above makes you sound?
@Bob Mahoney:
Sorry for the long post, you mentioned a subject I care about passionately. I see from your post that you’re well aware of the pros and cons of various staging points. I agree LEO has many disadvantages but despite these I still like LEO rendez-vous, but combined with L1/L2 rendez-vous. This accommodates smaller launchers and staging at the ISS or some future LEO staging point can reduce the hassle. If you have a larger rocket, you can go straight to L1 or some other suitable high-energy orbit and reduce phasing and nodal regression issues. I was once enthusiastic about DIRECT’s J-130 with the Delta upper stage for this purpose.
“The aid did it” excuse came after the fit hit the shan after the story of cutting Constellation in the name of education came out; I suppose we shall see just how much Obama does care about human spaceflight in the near future. Like past presidents, he may talk pretty and not actually invest a dime in stimulus money or political capital in doing anything…
CKilling Constellation for education would be a GOOD THING, because finally you idiots could get the education you so desperately need.
You can anticipate thousands of failure scenarios and add controls or fixes for all of them. You can do this one of two ways. You can do it with systems engineering – let’s call this the “NASA” method – spend billions over a decade or two on FMEA and err on the side of the safest (and likely most expensive) version of everything. Or you can do it with trial and error – let’s call the the “airplane” method – spend billions over a decade or two launching much cheaper depots in places where they are unlikely to cause serious debris problems for others, and use a constant redesign cycle to fix problems after they occur. In the second case, you get a market and utility during the FMEA, and the simulation is considerably higher fidelity.
Implying that we can design enough risk out of a prop depot in order to site it near the ISS is completely realistic. But doing so would make the prop depots just like the ISS – expensive, over-specialized, subject to the whims of too many interested parties, of limited use, and frozen to decades-old designs due to the cost of change orders. Prop depots near ISS aren’t unworkable per se, but they are unworkable in any meaningful timeline if you want to use a life cycle paradigm similar to what just about every non-civil-space engineering field uses.
@Roga:
Why would a depot 100km away from the ISS be risky? Especially a small hypergolic one, my favourite kind for the near future?
“It was revealed not long after the release of the Education Plan referred to in that article, that the part concerning the space program was inserted by an overzealous aid.”
And you probably believe in the tooth fairy as well.
In any case I voted and campaigned for McCain, so my hands are clean. Its the supporters of Obama who will have to explain to their grandkids why China, Russia and India are benefiting from their bases on the Moon and building ships to go to Mars while the U.S. is no longer a major player in space.
Its the supporters of Obama who will have to explain to their grandkids why China, Russia and India are benefiting from their bases on the Moon and building ships to go to Mars while the U.S. is no longer a major player in space.
Not that the current trajectory of the US space program is all that great, but the notion that those countries are going to have bases on the moon is ridiculous, given their own copycat and flawed approaches to the problem.
[…] Let’s face the fact that Democrats don’t give a damn about our future. “…The committee concluded that it would take an extra $50 billion to carry out the current plan, a chunk of money that most […]
why China, Russia and India are benefiting from their bases on the Moon and building ships to go to Mars while the U.S. is no longer a major player in space.
ROFLMAO
Are you serious ? Dude put down the crackpipe and rejoin reality.
Geez, kids today…
[…] senaste nu tycks vara att framtiden för amerikanska bemannade rymdfärder (som finansieras över skattsedeln – en del […]
the perfect vacumm wrote:
google translation Swedish>English:
past now seems to be the future of American manned space flight (which is financed by tax – part
Amerika är fortfarande i ridning cyklar i rymden. Eftersom de har ett förbud mot användning av nukleära framdrivningssystem för rymdfarkoster tillgång.
google translation Swedish>English:
America is still in riding bicycles in space. Because they have a ban on using nuclear propulsion for space access.
[…] cry has died down in recent months, particularly as the Augustine committee found evidence that keeping the current program on its current schedule may prove to be prohibitively expensive. That makes it difficult to push for trying to accelerate the current […]