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#160
by
rcaron
on 23 Apr, 2006 21:06
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Tyranny? Yes, whenever the Administrator does something unpopular it MUST be tyranny.
I'm not sure where the big push for EELV usage is even coming from. Its not like the future of the EELV launch market is dependant on manned spaceflight. EELV is doing fine with DoD, commercial flights, and now even a NASA probe or two. Besides, the last thing we need is the entire U.S. launch profile being limited to what potentially is one company (United Launch Alliance). There needs to be diversity in the launch vehicles to have any robustness when problems arise (and in this business, they always arise).
Shuttle gear is a different story. Once Shuttle retires, a huge workforce is suddenly out of a job, and the architecture of the program shows you can't really ramp down the workforce and work with a "skeleton crew" for the last few flights. There needs to be a smooth transition to CEV this time, not the horribly disjointed phase we saw going Apollo -> Shuttle. Thus, there needs to be something that uses Shuttle gear. But we can't just go and build CaLV - we have ISS to finish, and we're already cuttting missions left and right to make ends meet. So, what is an SDLV that can lift people? The answer is the pogo-stick, i mean CLV.
Of course, if Boeing & Lock-Mart really want to fly crews on the EELVs they can propose it - NASA is looking for crew/cargo services to ISS. SpaceX is already looking into it with their 3.8m Dragon capsule.
The goal here is diversity in technical capability, not reduction so the EELV is not the one-vehicle-fits-all launcher.... Like the Shuttle was supposed to be...
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#161
by
Tap-Sa
on 23 Apr, 2006 21:39
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rcaron - 24/4/2006 1:06 AM
Tyranny? Yes, whenever the Administrator does something unpopular it MUST be tyranny.
It's not about a certain space-Admin doing the unpopular thing. It's the general idea that government entity shuts out certain players from competing for contracts just because said entity and the players have different opinions about viability of the item being contracted. The contractor most vocally pushing it's own alternative solution could still be the one able to provide best bid to contracts the entity opts to have. This applies to any public spending, from making space hardware to paving roads.
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#162
by
rcaron
on 23 Apr, 2006 21:53
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Its clear that EELV does not suit NASA... and yet everybody is still pushing it. I can EASILY see them going to point of saying "if you say EELV one more time you won't get any contracts!" That is a powerful motivator.
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#163
by
Tap-Sa
on 23 Apr, 2006 22:37
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rcaron - 24/4/2006 1:53 AM
Its clear that EELV does not suit NASA
Maybe not 'as is'. But the Stick is still sort of soul-searching too. Would it be more cost-effective to modify existing real rockets to suit NASA, than trying to build something 'simple safe soon shuttle derived' (read: completely new launch vehicle with new engine and all) that aerodynamically resembles trying to shoot an arrow backwards, that is another question.
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#164
by
rcaron
on 24 Apr, 2006 00:22
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Tap-Sa - 23/4/2006 6:37 PM
Maybe not 'as is'. But the Stick is still sort of soul-searching too. Would it be more cost-effective to modify existing real rockets to suit NASA, than trying to build something 'simple safe soon shuttle derived' (read: completely new launch vehicle with new engine and all) that aerodynamically resembles trying to shoot an arrow backwards, that is another question.
Aerodynamics aren't an issue here. They did, after all, get the existing Shuttle stack to fly! A larger diameter upper fairing has been used by many an EELV, and they have successful flight profiles. We're talking active guidance here, not some passive rocket. These things can handle the aerodynamic loads just fine.
Its not a completely new launch vehicle. Saying the CLV is completely new is like my earlier (and wrong) comments in another thread about Atlas Phase 2 being "completely new". The SRBs have had 80 flights in tandem after the redesign and are one of the most reliable boosters in inventory. Granted, changes to the SRB will have to be made, and those are outlined in the ESAS report, but its not a huge deal.
The upper stage, granted, is a different story. There's no need to go through the whole SSME/J2-S/J2-S+/J2-X scenario again, but its worth mentioning that the existing upper stages on the EELVs were found to be insufficient too, and as such you ended up with various J2 configs on top of an Atlas. J2, while it hasn't been made in forever, is a good engine and is worth revising.
Again, if it were just a question of the pogo-stick or Atlas Phase 2, I'd go w/ the Phase 2. Even assuming for the moment that they both have the same R&D costs, failure rates, etc, the stick is more appealing to NASA since it uses existing procedures, hardware, and personell. is anybody really surprised here by this?
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#165
by
Jim
on 24 Apr, 2006 00:47
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Bruhn - 23/4/2006 12:46 PMKayla - 23/4/2006 8:26 AMNow start with a new launch vehicle (as CLV is) and tell me that the folks at MSFC can do better analysis on CLV than they can for the veteran Shuttle?
I can say with overwhelming confidence that the answer to this question is YES. I say that because comparing the CLV to the STS analytically is apples to oranges. A rocket is an order of magnitude easier to analyze than something as complex as STS was. A rocket can be analyzed with 1960s technology. You know the Saturn 1/1B was much harder to analyze than the Saturn V was with the Redstone and Jupiter tanks strapped together. In the late 50's early 60's, analyzing the coupled dynamics of those tanks strapped together was a challenge.There was no way a STS could be designed until the technology in analytical tools and computer technology was developed. Now you fast forward to today, and we are building a comparatively easy vehicle (analytically) AND we have all the latest analytical tools, AND we have all the heritage data, lessons learned, etc. So logically, the answer to your question is YES, MSFC can do better analysis on CLV than on STS.
It is not analysis he is referring to. It is the ability of MSFC to produce anything flightworthy. Since Saturn, track record is not good.
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#166
by
Jim
on 24 Apr, 2006 00:58
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Bruhn - 23/4/2006 12:46 PMKayla - 23/4/2006 8:26 AMNow start with a new launch vehicle (as CLV is) and tell me that the folks at MSFC can do better analysis on CLV than they can for the veteran Shuttle?
I can say with overwhelming confidence that the answer to this question is YES. I say that because comparing the CLV to the STS analytically is apples to oranges. A rocket is an order of magnitude easier to analyze than something as complex as STS was. A rocket can be analyzed with 1960s technology. You know the Saturn 1/1B was much harder to analyze than the Saturn V was with the Redstone and Jupiter tanks strapped together. In the late 50's early 60's, analyzing the coupled dynamics of those tanks strapped together was a challenge.There was no way a STS could be designed until the technology in analytical tools and computer technology was developed. Now you fast forward to today, and we are building a comparatively easy vehicle (analytically) AND we have all the latest analytical tools, AND we have all the heritage data, lessons learned, etc. So logically, the answer to your question is YES, MSFC can do better analysis on CLV than on STS.
Just a note about the analysis. The Saturns were overbuilt (much like most hw designed in that part of the country) , so detailed analysis wasn't required. MSFC hated the Centaur because it wasn't built like a bridge.
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#167
by
Jim
on 24 Apr, 2006 01:04
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rcaron - 23/4/2006 5:06 PM I'm not sure where the big push for EELV usage is even coming from. Its not like the future of the EELV launch market is dependant on manned spaceflight. EELV is doing fine with DoD, commercial flights, and now even a NASA probe or two. Besides, the last thing we need is the entire U.S. launch profile being limited to what potentially is one company (United Launch Alliance). There needs to be diversity in the launch vehicles to have any robustness when problems arise (and in this business, they always arise).
EELV is not doing fine, the companies are losing their shirts, that's why they are forming ULA. It maybe one company but it is two different rockets (except for 2nd engines).
The push for EELV's is because there are solutions out there that are cheaper and a just as safe.
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#168
by
kraisee
on 24 Apr, 2006 01:14
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I know quite a few of the guys managing and working on the CLV today. The ones I know ALL seem to have good experience and I see the "right stuff" in them to get the job done well.
I personally think the CLV is in pretty good hands at MSFC.
I've also been fairly impressed with the quality of the analysis work which is going on right now on Shuttle at different centers. I don't think anything as extensive as the current testing has ever been done since the inception of the program in the 1970's!
NASA has been flying Shuttle based LARGELY on 30 year old test data, but STS-107 inspired NASA to take another truly thorough look at the STS system, and with the far more capable analytical systems we have today, they've been able to identify a bunch of issues/problems we previously didn't have any idea about. That's a good thing because until you know what's wrong, you have no chance at fixing it.
I think that's all good news for the new program. The guys who will be evaluating and testing the CLV and CaLV are getting a real chance to dust off their skills on a very complicated vehicle indeed, and I think they'll be well-versed and highly experienced by the time they have to run the extensive tests on the new vehicles. I think the new program will be executed well, and I have a good degree of confidence in the people behind it.
Ross.
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#169
by
Jim
on 24 Apr, 2006 01:32
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kraisee - 23/4/2006 9:14 PMI know quite a few of the guys managing and working on the CLV today. The ones I know ALL seem to have good experience and I see the "right stuff" in them to get the job done well.I personally think the CLV is in pretty good hands at MSFC.
Good Experience? when has MSFC built anything flight worthy in house during the last two decades?
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#170
by
yinzer
on 24 Apr, 2006 03:52
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Indeed, NASA's experience at flying the Shuttle since STS-107 is not particularly stellar - one flight in three years? Two in four? Talk of cancelling it at that?
With NASA going to hypergolic propellants for lunar ascent and TEI, and something like half of the IMLEO being propellant, using the EELVs (built to support flight rates of 20 per year! each!) and doing on orbit propellant transfer has to be looking like a better way to go. If it can be done by 70's era Soviet computer technology, how hard can it possibly be?
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#171
by
rcaron
on 24 Apr, 2006 04:37
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yinzer - 23/4/2006 11:52 PM
Indeed, NASA's experience at flying the Shuttle since STS-107 is not particularly stellar - one flight in three years? Two in four? Talk of cancelling it at that?
I'm not thrilled with the Shuttle flight rate either, but the one flight in 3 years is unfair. It took ~2.5 years to get back from Challenger/51-L, and we had a similar timeline for Columbia/107. Still, that leaves us at a rate of one launch per year, and we have 18 flights left and 3.5 years to do it.
These delays are driven by the fact that the Orbiter is a complicated machine and that we can't afford significant debris hitting the TPS. The CLV fixes that issue entirely. The Shuttle stack is good hardware, we just put the pieces together wrong...
yinzer - 23/4/2006 11:52 PM
With NASA going to hypergolic propellants for lunar ascent and TEI, and something like half of the IMLEO being propellant, using the EELVs (built to support flight rates of 20 per year! each!) and doing on orbit propellant transfer has to be looking like a better way to go.
20 flights/year eh? I'm not so sure how realistic that is. Point in case - Delta strike. You want to have cyro tanks venting valuable propellant on orbit while we're working out employee benefits? I saw some plans that used EELVs entirely - for crew & cargo - and we were talking 6-8 launches for just a Moon flight! The chances of delays, docking failures, etc are far too high to risk that.
yinzer - 23/4/2006 11:52 PM
If it can be done by 70's era Soviet computer technology, how hard can it possibly be?
Talk to the Europeans building the ATV (I had the fortunate opportunity to do so during a conference). The biggest difficulty they have had is the trying to replicate that Soviet computer technology and interface it with modern hardware. Also, given the # of EELV launches required for a lunar flight, the Soyuz/Progress has a very high risk of failing automatic. I don't have all the numbers offhand, but I distinctly recall automatic fouling up on more than one Soyuz/Progress occassion in recent past, and with 2 Soyuz/year and maybe 3 Progres/year, if you take the last 1.5 years or so of ISS history you have the equivilant difficulty of an EELV-lunar assembly. And, within the last 1.5 years, automatic docking has failed.
So, given that we can't actually reproduce Soviet technology, and that Soviet technology isn't even reliable enough, I think EELV for CaLV use is completely out of the question. Its debatable for CLV, but no way for CaLV.
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#172
by
Kayla
on 24 Apr, 2006 13:26
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You are completely missing the point.
Some of us would actually like to see us explore the Moon and Mars rather than watch NASA spend the next 12 years and $20B trying to prove that they can design 2 rockets (CLV & CaLV).
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#173
by
Kayla
on 24 Apr, 2006 13:36
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You are right on track!!! If America truly wants a robust space program we must get over this rendezvousing and docking fear (Crewed, Automated and tele-operated). A Mars sample return mission will require AR&D in Mars orbit. Even with a CaLV, a Mars mission will require 4 or 5 launches. Does NASA intend to have crew in space for each docking??
The only reason for a CaLV is to launch propellant to orbit. The actual hardware (LSAM & EDS) is actually quite light. Using AR&D with propellant transfer eliminates the need for the CaLV and its $10B price tag. Not only this, but it provides flexibility to the Architecture. NASA is going around in circles right now over performance on the CLV. This will be much worse on the CaLV. Having the ability to simply add another launch and fill the EDS up a little more allows the exploration architecture to accommodate changing mission demands, or worse boil-off than predicted.
Just as importantly is that the launch of propellant opens the door up to true launch competition. This is especially true if NASA has an orbital maneuver vehicle to do the AR&D and the launchers simply lob propellant into the correct orbit. Competition is truly American. This is how we will bring the cost of space access down to the point where commercial tourism and eventually colonization can actually come to pass.
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#174
by
Bruhn
on 24 Apr, 2006 14:58
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Jim - 23/4/2006 8:32 PM
kraisee - 23/4/2006 9:14 PMI know quite a few of the guys managing and working on the CLV today. The ones I know ALL seem to have good experience and I see the "right stuff" in them to get the job done well.I personally think the CLV is in pretty good hands at MSFC.
Good Experience? when has MSFC built anything flight worthy in house during the last two decades?
Its not MSFC's mission to build flight hardware in house. We only have limited capability here. And I fail to see why you consistently heap all failure responsibilities on MSFC. How about spreading the negativity around some.
If I were an astronaunt, and I truly wish I were, I would much rather place my life in the hands of a NASA developed LV where safety was the bottom line as opposed to an EELV whose bottom line was $$$. It has always been NASA's policy that human tended spacecraft/modules use factors of safety of 1.4. If you want to refer to this policy as 'bridge building', then thats your opinion.
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#175
by
Jim
on 24 Apr, 2006 15:30
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Bruhn - 24/4/2006 10:58 AMJim - 23/4/2006 8:32 PMkraisee - 23/4/2006 9:14 PMI know quite a few of the guys managing and working on the CLV today. The ones I know ALL seem to have good experience and I see the "right stuff" in them to get the job done well.I personally think the CLV is in pretty good hands at MSFC.
Good Experience? when has MSFC built anything flight worthy in house during the last two decades?
Its not MSFC's mission to build flight hardware in house. We only have limited capability here. And I fail to see why you consistently heap all failure responsibilities on MSFC. How about spreading the negativity around some.If I were an astronaunt, and I truly wish I were, I would much rather place my life in the hands of a NASA developed LV where safety was the bottom line as opposed to an EELV whose bottom line was $$$. It has always been NASA's policy that human tended spacecraft/modules use factors of safety of 1.4. If you want to refer to this policy as 'bridge building', then thats your opinion.
Where was the 1.4 for the Mercury Atlas and Gemini Titan?
It depends on what you pay for. Yes, the
current EELV's were build for cost, but doesn't mean human rated ones would be.
Look at MSFC's past record, OSP, orbital X-37, X-34, X-33
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#176
by
Tap-Sa
on 24 Apr, 2006 17:02
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rcaron - 24/4/2006 4:22 AM
We're talking active guidance here, not some passive rocket. These things can handle the aerodynamic loads just fine.
Glitch in said active guidance means real bad day. Say TVC jams while nozzle is not pointing straight 'down'. You have oodles of torque trying to flip your already aerodynamically unstable vehicle, due to high thrust which you cannot turn off.
Another though about the loads; IIRC Challenger failure happened due to wind sheer bending a case joint so that blowby occured from previously damaged seal. This bending happened even when both ends of the SRB were attached to the ET. The only lateral force came from the wind, when SRB nozzle gimbals the aft attachment carries most of the torque elsewhere to the stack, no? When the Stick SRB gimbals the torque is carried through every joint, as is, since it's attached only from it's nose to payload on top. Possibly there's even fifth segment, another joint, longer stick, longer arm for torque. I'm not expert on structures at all but the way SRB is set up in CLV seems much more dangerous than how it's used in STS.
the stick is more appealing to NASA since it uses existing procedures, hardware, and personell. is anybody really surprised here by this?
Unfortunately no
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#177
by
yinzer
on 24 Apr, 2006 17:58
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Bruhn - 24/4/2006 7:58 AM
If I were an astronaunt, and I truly wish I were, I would much rather place my life in the hands of a NASA developed LV where safety was the bottom line as opposed to an EELV whose bottom line was $$$. It has always been NASA's policy that human tended spacecraft/modules use factors of safety of 1.4. If you want to refer to this policy as 'bridge building', then thats your opinion.
How many safety waivers are there expected to be for the next Shuttle flight?
And how many unmanned launches have failed due to insufficient (1.4/1.2) structural safety margin? These days launch vehicles fail due to poorly understood interactions between components and procedural errors, neither of which are particularly helped by higher structural margins, and both of which are made much, much worse by inexperience building and flying rockets. An EELV that has flown 20 or 30 times is going to be pretty well wrung out, especially compared to a CaLV that flies once or twice a year, and was designed by people who haven't designed a rocket that flew in 20 years.
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#178
by
Jim
on 24 Apr, 2006 18:21
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yinzer - 24/4/2006 1:58 PMBruhn - 24/4/2006 7:58 AMIf I were an astronaunt, and I truly wish I were, I would much rather place my life in the hands of a NASA developed LV where safety was the bottom line as opposed to an EELV whose bottom line was $$$. It has always been NASA's policy that human tended spacecraft/modules use factors of safety of 1.4. If you want to refer to this policy as 'bridge building', then thats your opinion.
How many safety waivers are there expected to be for the next Shuttle flight?And how many unmanned launches have failed due to insufficient (1.4/1.2) structural safety margin? These days launch vehicles fail due to poorly understood interactions between components and procedural errors, neither of which are particularly helped by higher structural margins, and both of which are made much, much worse by inexperience building and flying rockets. An EELV that has flown 20 or 30 times is going to be pretty well wrung out, especially compared to a CaLV that flies once or twice a year, and was designed by people who haven't designed a rocket that flew in 20 years.
Great point
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#179
by
Norm Hartnett
on 25 Apr, 2006 01:45
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Well this thread has wandered well OT but it is such a good discussion that I can understand the Moderator not pulling in the leash.
I’ve been catching up on my reading since I joined this forum and have spent most of the day reading this thread as well as the CEV and CLV threads. Since I am not a rocket scientist (unlike Jim) I have a few questions.
Where did the $500M per launch figure for the stick come from and is it accurate?
Is the $1B-3B development and man rating figure for the stick correct?
What is the cost of man rating the EELVs?
What are the cost figures looking like for vehicle prep and launch facilities between the stick and the EELV?
Will use of the EELV for VSE lower the cost of the EELV for both AF and NASA?
Does not using the stick for the CLV preclude the CaLV?
And finally back on topic.
If MSFC and the AF have been and are continuing to work on LOX/Methane engines why did the requirement get dropped in the first place? And what is the AF going to do with that engine anyway?
