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#60
by
Avron
on 02 Feb, 2006 05:11
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Just thinking of what launch systems NASA has that can lift anything into LEO, nevermine beyond that... and before you jump at Delta, Atlas... who owns these...Nasa?.. Me thinks is all commercial with a little help from gov. The STS however, is not commercial, but components are supplied by vendors and the same is true for service...
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#61
by
stargazer777
on 02 Feb, 2006 12:21
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"Honestly, I think the public will be more interested in the destination for craft rather than the design of the vehicle."
"The public is bored with the "routine missions" to the frankly pointless ISS, even though many here seem to think STS is more sexy than CEV - it has just become boring to most taxpayers."
You are absolutely right. In fact, I believe that Griffin has said essentially the same thing in his public statements and internal messages. In allowing itself to be trapped in LEO, NASA lost the imagination of the Amercian public and the world. Even if the Shuttle had not had the terrible accidents and the ISS the repeated lengthy delays, that would still be the case. Although the NASA exploration architecture is not as sexy as we might wish, by having an ambitious exploration goal and being able to demonstrate real progress toward achieving it, we will begin to reclaim the crucial imagination and support of the public and through that ensure the long term survival of the program. This will also shift the debate away from why should we have any manned space to what we should be doing in space and, believe or not, pressure to do it more quickly. I am certain that we will see a rapid evolution in the hardware we send up and how we use it. Once we have the basic hardware capability -- particularly the heavy lift -- it won't take much additional funding (beyond the baseline budgets expanded for inflation and some small programatic expansions) to begin to put some significant improvements in capability in the program. For example: Orbital or L1 refueling and assembly of more complex vehicles and components; a quick and dirty space station along the lines contemplated by Bigelow in the right orbit that can actually be used to facilitate the Moon/Mars effort -- something that can basically be put up in a couple of heavy lift launches; a serious advance in the nuclear side with both power generation (for powering lunar and space based facilities) and propulsion for longer range exploratory missions; assembly of pure space vehicles that can be used to transport people and cargo back-and-forth to the Moon and later Mars and beyond so that we can quickly get beyond the throw-away mentality; and that is just the beginning. Of course, there will be plenty of opportunity for those "inherently superior" private sector concepts to support, supplement and reach beyond this program. Think about it -- does anyone care about the vehicles we use to support the Antarctic bases? Of course not. Once we are really out there, the destination and the mission becomes the "thing", everything else will fade into the background.
I would also like to add my voice to those who are deeply disappointed by the extremely negative web reviews of virtually everything NASA does by sources such as NASA Watch, Encyclopedia Astronautica, and others. Personal opinions are fine, but these and other sites are pose a real risk at poisoning the well. Clearly these are deeply disappointed people -- by the space program and probably other things in their lives. The problem is that they offer themselves as having a unique knowlege/insight into the space program and are widely read by those who either aren't sophistacated enough or won't take the time to see through the bias and frustration that runs rampant in their articles. No matter what course NASA chooses, these sources will never be satisfied. Actual supporters of manned space flight and exploration must realize that this program survives on a razor's edge -- with enemies on all sides who would love to take NASA funding in toto and devote it to whatever pet project they are advocating. The issue is not between funding NASA and some idealized space transportation system -- the issue is funding manned space flight at all. And, as several of the other commentators have noted, don't doubt the link between funding for robotic missions and support for manned space. If manned space goes, it won't take long for robotic missions to wind down dramatically -- perhaps even disappear. Manned space is the "long pole in the tent" as far as funding for space is concerned. Take it out, and the whole thing collapses.
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#62
by
vt_hokie
on 02 Feb, 2006 16:31
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stargazer777 - 2/2/2006 8:21 AM
No matter what course NASA chooses, these sources will never be satisfied.
This is the only part of your post that I must really disagree with. I would be quite satisfied with a reusable lifting body spaceplane!
I was even somewhat intrigued by Lockheed's lifting body CEV design, before NASA shot that down.
But I suppose a modernized Apollo capsule is better than nothing. I'm still not sold on the safety of using SRB's for launching it. Aren't there certain failure modes that will allow no time for the launch escape tower to get the capsule clear of the booster? People often criticize the space shuttle design for being a kludge that was defined by politics and budget restrictions more than technical merit. The same could be said for the CEV.
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#63
by
vt_hokie
on 02 Feb, 2006 16:36
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vanilla - 1/2/2006 11:36 PM
Keep it clean, buddy...some of us don't like that kind of language.
Sorry, no disrespect intended, just a bad habit I've picked up of using slang terms without even thinking about it.
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#64
by
Dogsbd
on 02 Feb, 2006 16:42
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vt_hokie - 2/2/2006 12:31 PM
This is the only part of your post that I must really disagree with. I would be quite satisfied with a reusable lifting body spaceplane!
Even though there is no logical reason, from a cost of operation and capacity to perform the given mission standpoint, that such a vehicle design should be chosen.
vt_hokie - 2/2/2006 12:31 PM
Aren't there certain failure modes that will allow no time for the launch escape tower to get the capsule clear of the booster? People often criticize the space shuttle design for being a kludge that was defined by politics and budget restrictions more than technical merit. The same could be said for the CEV.
Of course there may be "some" failure modes that prohibit escape/survival, but who expects perfect safety? We might as well stay on the ground if that is an expectation. There are failure modes on 747's that will kill everyone on board, yet we still fly 747's.
At this point it doesn't matter if Shuttles problems were manifested out of politics or budget restrictions, what matters is that the problems exist and we need something to replace it that doesn't have those problems, or at least fewer problems.
Suffice it to say that the CEV should be leaps and bounds ahead of the Shuttle with respect to safety.
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#65
by
vt_hokie
on 02 Feb, 2006 17:11
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Dogsbd - 2/2/2006 12:42 PM
Even though there is no logical reason, from a cost of operation and capacity to perform the given mission standpoint, that such a vehicle design should be chosen.
Developing a true STS version 2.0, freed from the Air Force interference that resulted in some of the space shuttle's compromises, would give us a more capable next generation space shuttle that would be capable of delivering the remaining ISS components, servicing ISS, and performing Hubble servicing types of missions (and even returning Hubble - it's a shame that it will never see the Smithsonian).
Can I say that it would be worth the development cost for the incremental improvement over STS version 1.0? That's hard to say. But I do think that the remarkable, and indeed unprecedented capabilities of the space shuttle are worth quite a bit.
Honestly, I would love to see both a reusable space shuttle for LEO operations and a "CEV" type of vehicle for beyond-LEO missions. It's a shame that we always have to choose between one thing or the other with our space program. But that is a good example of why we need to either double NASA's budget or significantly reduce launch/operations costs.
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#66
by
Dogsbd
on 02 Feb, 2006 18:13
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vt_hokie - 2/2/2006 1:11 PM
Developing a true STS version 2.0, freed from the Air Force interference that resulted in some of the space shuttle's compromises
The Air Force had nothing (or little) to do with the shuttle ending up requiring months worth of turn around time (and 10's millions of dollars, at least, worth of turn around expense) as opposed to the days of turn around time that it was supposed to require. Therein lies one of the major reasons that the shuttle is so expensive to operate and I know of no technological advancements that would change that to a great extent on STS 2.0. Plus the arguments on flight rates for RLV’s that have already been made in other threads of late.
We are nowhere near having the technology to the equivalent of an orbital DC-3.
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#67
by
BogoMIPS
on 02 Feb, 2006 18:40
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Dogsbd - 2/2/2006 1:13 PM
We are nowhere near having the technology to the equivalent of an orbital DC-3.
Yup. I think we need a couple more generations of technology before winged orbiters become more viable:
First, you need to achieve single-stage to sub-orbital winged travel, for a manageable cost. At that point, the military and/or commercial travel will grab on to it. Scramjets, or some similarly-revolutionary propulsion system will make a commercial skip-liner (or skip-bomber) possible at some point.
Once you have that, you can scale up to the point that you can afford the additional mass for add-on non-air-breathing engines, or some hybrid LOX-injected air-breather, for the push to LEO.
The development time on an STS v2.0 is probably an order of magnitude more than Apollo v2.0, especially if you want it to still carry the same payloads.
If we had the budget for both, even better, but we know how that's worked out in the past.
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#68
by
gladiator1332
on 02 Feb, 2006 19:33
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What I hope we see with the CEV is something similar to what we saw with Gemini....and I think this may be something NASA already has in mind. Right now we have the basic capsule, sm, parachute landing, ya know that whole bit. But I hope as the missions continue on, NASA still looks for improvement and tests out new methods for landing (maybe a return to the paraglider) New fuels for the SM. Instead of keeping the design frozen for the next 30 years like we have with the Shuttle, NASA should still continue to test new ideas as the Moon missions continue on.
The great thing about the CEV is that it will be cheaper than say a Shuttle to build. The only way to test a new idea for the Shuttle would be to fly it on a manned mission, and this would not be safe. With the CEV, and unmanned test version could be built and new SMs and landing methods could be tested.
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#69
by
HarryM
on 02 Feb, 2006 23:24
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Dogsbd - 2/2/2006 11:13 AM
vt_hokie - 2/2/2006 1:11 PM
Developing a true STS version 2.0, freed from the Air Force interference that resulted in some of the space shuttle's compromises
The Air Force had nothing (or little) to do with the shuttle ending up requiring months worth of turn around time (and 10's millions of dollars, at least, worth of turn around expense) as opposed to the days of turn around time that it was supposed to require. Therein lies one of the major reasons that the shuttle is so expensive to operate and I know of no technological advancements that would change that to a great extent on STS 2.0. Plus the arguments on flight rates for RLV’s that have already been made in other threads of late.
We are nowhere near having the technology to the equivalent of an orbital DC-3.
I think the changes that the AF required did make it harder to support, though the Max Faget version would still have had tiles, it would have had less of them. The sheer number of tiles seems to drastically impact the amount of servicing work required. The person-hours required to replace just 1 tile is amazing since they are all unique and have to be manufactured and precisely hand-fitted into place.
...
To give the Air Force its 1100 n.mi. of crossrange would impose a serious penalty in design, by requiring considerably more thermal protection. The change to a delta wing, even without crossrange, would add considerably to the wing area demanding such protection. Crossrange then would increase this requirement even further. The Shuttle would achieve its crossrange by gliding hypersonically, and hence would compromise the simple nose-high mode of reentry that would turn it into a blunt body. This hypersonic glide would produce more lift and less drag. It also would increase both the rate of heating and the duration of heating. Crossrange thus would call for a double dose of additional thermal protection, resulting in a shuttle that would be heavier-and more costly.
...
http://history.nasa.gov/SP-4221/ch5.htm
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#70
by
vt_hokie
on 03 Feb, 2006 04:38
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gladiator1332 - 1/2/2006 3:52 PM
I think SpaceDev is wokring on something as well. Originally their design was an X-34 clone, however, they switched to a lifting body design recently.
If I remember correctly, SpaceDev estimates that it could develop the orbital version of its HL-20 derived "Dreamchaser" for ~$100 million. I have my doubts, but if that does turn out to be true, why does NASA need billions for even less ambitious projects? Heck, they spent over $1 billion on X-33 and didn't even have anything to show for it!
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#71
by
MATTBLAK
on 03 Feb, 2006 04:46
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I was FURIOUS when the X-38 was cancelled. An assured crew return vehicle that wouldn't have been effected by the Columbia tragedy AND with a possible upgrade path to a crew transport, to and fro from a lunar or Mars vehicle. In other words, with an attached propulsion module: a CEV, albeit a very basic one! The X-38 program had the misfortune of occurring during the most miserly funding for Nasa of recent history, and during a strong U.S. economy, too. During the days of X-38 and early ISS, manned spaceflight had powerful enemies...
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#72
by
vt_hokie
on 03 Feb, 2006 04:49
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MATTBLAK - 3/2/2006 12:46 AM
I was FURIOUS when the X-38 was cancelled.
Me too. But hey, it's never too late to bring it back!
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#73
by
Dobbins
on 03 Feb, 2006 12:26
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The X-38 is the poster boy of what is wrong with NASA development. At a time when the agency needed to be developing a replacement for an aging shuttle fleet it was spending scarce funds on a vehicle of very limited capabilities. One that couldn't even get into space on it's own, but which had to be lofted to orbit inside a shuttle's cargo bay. One that couldn't do squat after it got there, just stay attached to the ISS in case something went wrong. This is precisely the kind of project you don't invest in when you have limited funding.
So just where would we be if development of this thing had continued? If it was ready right now we would have a spaceplane that couldn't get to space until the shuttle passed it's RTF, and one that would then have to stand in line waiting for a spot on the shuttle manifest before it could perform it's very limited mission. That's real friggin' useful.
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#74
by
vt_hokie
on 03 Feb, 2006 16:48
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Dobbins - 3/2/2006 8:26 AM
So just where would we be if development of this thing had continued? If it was ready right now we would have a spaceplane that couldn't get to space until the shuttle passed it's RTF, and one that would then have to stand in line waiting for a spot on the shuttle manifest before it could perform it's very limited mission. That's real friggin' useful.
That's a fair point. I guess my reply would be this: we'd be halfway toward having a reusable crew transport. It wouldn't be much of a stretch to adapt the vehicle design for launch on one of our expendable boosters. I always pictured the CRV eventually ending up on top of an Ariane V. European collaboration was a no brainer after the failure of their Hermes program.
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#75
by
Dogsbd
on 03 Feb, 2006 17:01
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vt_hokie - 3/2/2006 12:48 PM
That's a fair point. I guess my reply would be this: we'd be halfway toward having a reusable crew transport.
X-38 was far from being even halfway to a "real" spacecraft, and I'm not at all sure that it's TPS was reusable. Why would what is esentially an escape pod need reusable TPS?
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#76
by
nacnud
on 03 Feb, 2006 17:11
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The TPS was reuseable and had been developed by Dasa for the ESA Hermies project. In fact I think all the X-38 TPS was provided by partnership with ESA.
Link
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#77
by
publiusr
on 03 Feb, 2006 17:45
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I think it is time that a gallery of CEV/Stick HLLV images like what is scattered around here be put together in a counter to Wade's CEV section. Then it could be linked to Wiki as a better source of info. Wade really needs to take a break. At least he is actually updating his website.
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#78
by
Daniel Handlin
on 04 Feb, 2006 01:23
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Honestly I wrote a good deal of the Wikipedia CEV article - nearly all of it, in fact. Then when I stopped updating it, no one else did. That's why it's stuck in time around late August or so. One of these days I'll get around to updating it. But I admit that now it's getting a little dated. Mr. Wade does often take a while to update his site. If only he stuck to the technical details, with which all of his other articles are so excellent... he bills himself as an encylcopedia. Never have I seen an encyclopedia where the main articles say "this is good" or lambast them for being really bad (and he certainly does a lot more of the latter). I can just imagine, in the Encyclopedia Britannica:
Macropaedia. Volume C.
Crew Exploration Vehicle:
A misbegotten decision that signalled the end of American human spaceflight.
Ridiculous. Give us the technical details! He should relegate his personal opinions to his blog, not to his articles. Or at least he should provide the counterpoints in his articles too; if you're not willing to fully examine both sides of the issue, then you do not really understand it and you can't support your own viewpoint.
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#79
by
MATTBLAK
on 04 Feb, 2006 04:54
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I agree!! Mark Wade is cheapening his considerable currency by editorialising his Encyclopedia this way. He should leave such comments to his Blogsite.
I was even somewhat intrigued by Lockheed's lifting body CEV design, before NASA shot that down.