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MSNBC (JimO) - Hubble debate -- a lot of sound and fury
On Tue, 23 Mar 2004 17:39:36 -0400, John Doe wrote:
BenignVanilla wrote: the politically safe path, and not launching to the Hubble. The nation cried foul when the second shuttle was lost, and NASA is responding in CYA fashion Did the nation really cry foul ? If NASA can't fly the shuttle to Hubble for safety reasons, that it shouldn't be flying it at all. Shuttle was designed for that type of mission, it isn't as if you're asking it to be outfitted with additional SRBs that could send it to the moon. While I can understand a Hubble mission can't be flown until they have the right self-contained repair procedures, I think it is important for NASA to get those. That expertise isn't required just for Shuttle, but for all subsequent vehicles. Being able to fix stuff in space is very important, especially if you're going beyond LEO for long durations. And yes, this means that NASA needs to widen the envelope of EVA procedures to find safe ways for Crew members to go to places they are currently prohibited from going. In fact, NASA's refusal to go to Hubble means that NASA isn't confortable for the Shuttle's safety. The day NASA re-instantes the HUbble flights is the day I will trust that NASA has truly ficed the foam problems and implemented CAIB recommendations. excellent points! |
#112
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MSNBC (JimO) - Hubble debate -- a lot of sound and fury
Pat Flannery writes:
jeff findley wrote: If your only metric is innovation. Unfortunately, when you have a fixed budget (which X-33 essentially had), there is an inverse relationship between innovation and successfully completing a flight test program. In other words, the entire program was shut down before all of the bugs could be worked out in the innovative areas. The Skunk Works broke one of its own rules on that project- one _and only one_ new breakthrough technology per project. They tried a linear plug nozzle motor, lightweight metallic TPS, and composite LH2 tanks all at once- that was just begging for failure. Agreed, but NASA didn't care to see it this way. The linear plug nozzle motor was based on previous research and on a proven "powerhead", so they didn't see that as being breakthrough. As you say later Lockheed implied that the composite LH2 tanks weren't breakthrough, hinting strongly that they had done them before (on a black program). That left the metallic TPS as the only breakthrough technology. NASA fell in love with the three new technologies in the Lockheed bid and picked a "winner" that turned out to be a hangar queen. In the end, NASA's official position is that X-33 failed because we do not yet have the technology to produce a workable SSTO. Remember the Lockheed CL-400 Suntan though- it also was a complete flop, but taught a lot of lessons on how _not_ to do things that paid off in the A-12/SR-71 projects. Unfortunately, I'm not sure NASA really learned its lesson. They appear to be completely backing away from reusable technology as applied to launch vehicles, because they think the technology isn't there. It's far more likely that X-33 failed due to mismanagement of the program, which started with picking the wrong "winner". It would have been beneficial to run the program as three separate *truely* X-programs. One to test the aerospike, one to test lightweight structures (e.g. integrated, structural, composite, LH2 tanks), and one to test metallic TPS. Instead of admitting this, NASA instead blamed the failure on the lack of technology, instead of blaming it on how their overall technology development program was being run. In the end, this program did more harm than good, especially when NASA refuses to admit any guilt as it relates to the program's failure. I think NASA got sold a line of bull by Lockheed Martin, especially when Lockheed implied that a lot of the technology that they would be using was based on something classified that they did...and which they couldn't talk about (wink, wink). Whatever it was, it apparently didn't use composite LH2 tanks, did it? If it did, apparently they weren't integrated, structural, multi-lobed, composite, LH2 tanks. Those tanks were complicated in *many* different design variables. Jeff -- Remove "no" and "spam" from email address to reply. If it says "This is not spam!", it's surely a lie. |
#113
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MSNBC (JimO) - Hubble debate -- a lot of sound and fury
The probe wasn't lost because of a human error in units. It was lost
because the Goldin-style faster-better-cheaper mantra required a process in which humans were perfect, and didn't need checking. THAT was the cause of the disaster, not the fact that the project was implemented by normal human beings. Good points here but still I think it should not have happened at all. Orbit insertion has been accomplished so many times that the logic surrounding the parameters should be COTS. I could realy imagine someone make a sourceforge project surrounding it. I guess many students would love the promise of real implementation. Sincerely Bjørn Ove |
#114
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MSNBC (JimO) - Hubble debate -- a lot of sound and fury
"Derek Lyons" wrote in message ... [snip] With public support for NASA being rather sparse these days, it might be a good idea to not trash an existing project that clearly has the public's support, even if it doesn't make complete sense to those who are better informed. Right. So we turn the space program over to the masses as a bread and circuses progam. D. Who's paying the bills? LB |
#115
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MSNBC (JimO) - Hubble debate -- a lot of sound and fury
Jonathan Silverlight
wrote: [...] There are also a lot of pretty pictures showing people fixing Hubble. Except for Hubble repair missions, US manned space flight in the last 20 years or so has been a mixture of absolute disaster and deep embarrassment - blocked toilets on the Shuttle, an astronaut using a pipe as a handle and causing a leak on ISS, joyrides for politicians with more than a hint of corruption. Uhhh, if that's all you can remember out of 20 years, then perhaps you're paying less attention than the general public. Blocked toilets were a recurrent problem in the early missions, but *did* get solved. The politicians no dobut flew because of priviledge, but where is any evidence of corruption? LDEF, SRTM, various satellite launchings (yes, those could have been done on expendables, but since they were done on the Shuttle they count as part of the Shuttle's accomplishments), the electric tether, Spacelab, Spacehab, reboosts of Mir, reboosts of ISS, ... There's now talk of a robot mission to replace Hubble's batteries. If they can pull that off, one of the last justifications for manned space flight disappears until/unless it is reborn as a commercial venture. This seems to be an incoherent statement. I thought you were a little more informed than "to replace Hubble's batteries", and if a robot service mission to Hubble is all it takes to remove justification for manned spaceflight, then maybe we *should* give up manned spaceflight. (For me, manned servicing missions are merely a side benefit, since I think we should be out there JUST BECAUSE. I realize that budget planners listening to taxpayer screams need something more). /dps |
#116
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MSNBC (JimO) - Hubble debate -- a lot of sound and fury
"Jorge R. Frank" writes:
Indirectly, yes. NASA took over DC-XA when SDIO cancelled it. When it came time for the next phase, which would have been DC-Y. NASA re-competed the contract under the name X-33 rather than sole-sourcing it to MDAC. Procurement law sets out specific circumstances under which sole-sourcing is allowed (small contracts or lack of other suppliers in the market), and the circumstances of DC-X did not fit: the contract was too large and there were other suppliers in the market. Had NASA sole-sourced it anyway, it would have invited legal challenges from other potential suppliers and a lot of scrutiny from Congress. MDAC bid on the re-competed contract but lost to LockMart. We can debate the relative merits of the X-33 competitors (personally I preferred MDAC and Rockwell's designs over LockMart's), but not the necessity of re-competing the contract. There's something that bugs me about that argument: When they recompeted the contract, they did not compete a contract for DC-Y. They competed it for something completely different; the resulting vehicle was not a decent followon capable of expanding the envelope of DC-X. It was a different vehicle with a different flight profile. -- Phil Fraering http://newsfromthefridge.typepad.com "Something's just not right..." "Sweetie, we're criminals. If everything were right, we'd all be in jail." |
#117
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MSNBC (JimO) - Hubble debate -- a lot of sound and fury
Phil Fraering pgf@AUTO wrote in
: "Jorge R. Frank" writes: Indirectly, yes. NASA took over DC-XA when SDIO cancelled it. When it came time for the next phase, which would have been DC-Y. NASA re-competed the contract under the name X-33 rather than sole-sourcing it to MDAC. Procurement law sets out specific circumstances under which sole-sourcing is allowed (small contracts or lack of other suppliers in the market), and the circumstances of DC-X did not fit: the contract was too large and there were other suppliers in the market. Had NASA sole-sourced it anyway, it would have invited legal challenges from other potential suppliers and a lot of scrutiny from Congress. MDAC bid on the re-competed contract but lost to LockMart. We can debate the relative merits of the X-33 competitors (personally I preferred MDAC and Rockwell's designs over LockMart's), but not the necessity of re-competing the contract. There's something that bugs me about that argument: When they recompeted the contract, they did not compete a contract for DC-Y. They competed it for something completely different; the resulting vehicle was not a decent followon capable of expanding the envelope of DC-X. It was a different vehicle with a different flight profile. The particular flight profile was not relevant; the overall goal (an SSTO RLV with low per-flight cost) was. So the RFP was written generally enough for competing approaches to be tried - otherwise, the RFP would have been a disguised sole-source solicitation to MDAC, since they were the only ones proposing an SSTO with that particular flight profile. I was a bit surprised to see NASA write the RFP generally; usually, they are guilty of overspecifying it to the point that you can tell they had a particular company/product in mind and wrote the RFP to practically assure that only that product could win. At least in this area, NASA got X-33 right, in my opinion. Where NASA screwed up on X-33 was to equate the amount of new technology in a vehicle with the cost reduction it would be able to achieve, which is fallacious. So they picked Lockheed's bid, which promised the steepest cost reductions, but also had the most new technology crammed into one vehicle, and therefore the most technical risk of all three bidders. Then, when the development program (predictably) failed, NASA proclaimed that the technology just wasn't there for SSTO, despite the fact that the two losing bids had less technical risk and could well have worked. Of course, with MDAC and Rockwell both subsequently swallowed by Boeing, we'll probably never know for sure. I would have preferred to see all three bids funded to a fly-off, as the DoD often does with aircraft procurements. It would have cost the government more up-front but would be far less likely to result in failure. It looks like CEV may be taking this approach. -- JRF Reply-to address spam-proofed - to reply by E-mail, check "Organization" (I am not assimilated) and think one step ahead of IBM. |
#118
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MSNBC (JimO) - Hubble debate -- a lot of sound and fury
"Jorge R. Frank" writes:
I would have preferred to see all three bids funded to a fly-off, as the DoD often does with aircraft procurements. It would have cost the government more up-front but would be far less likely to result in failure. It looks like CEV may be taking this approach. Let's hope so, especially for the crew launch/entry module. Since the CEV appears to be a more modular vehicle, there isn't really any reason to give all of the pieces to one contractor. You may want a prime contractor to oversee everything, but that doesn't mean that entire modules couldn't be subcontracted out. Jeff -- Remove "no" and "spam" from email address to reply. If it says "This is not spam!", it's surely a lie. |
#119
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MSNBC (JimO) - Hubble debate -- a lot of sound and fury
In article ,
jeff findley wrote: "Jorge R. Frank" writes: I would have preferred to see all three bids funded to a fly-off, as the DoD often does with aircraft procurements. It would have cost the government more up-front but would be far less likely to result in failure. It looks like CEV may be taking this approach. Let's hope so, especially for the crew launch/entry module. Since the CEV appears to be a more modular vehicle, there isn't really any reason to give all of the pieces to one contractor. You may want a prime contractor to oversee everything, but that doesn't mean that entire modules couldn't be subcontracted out. Jeff That approach was tried for SSF. Work Package 1 was all the pressurized elements and internal systems, contracted to Boeing. Work Package 2 was the integrated truss and external systems like the TCS radiators, integration of the PV arrays with the truss and power storage/distribution systems, external GNC stuff, etc, contracted to McDonnell Douglas; Work Package 3 disappeared early on and I can't remember all of what they were to do - earth observation science stuff, I think; WP 4 was solely the external electrical stuff like batteries, power regulators, etc., IIRC. WP1 wasn't really in charge although it was sort of seen as "first among equals." There was (theoretically) a central SSF Program Office at NASA HQ that was in charge but they were far-removed from things happening in the detailed design process and not very effective at all at controlling the various Center contracting offices for the various work packages (which were at MSFC, JSC and Goddard), let alone influencing the contractors directly. Anyway, the hassles of having so many organizations involved with so many facets of the design process really slowed things down and complicated matters greatly. Just flowing interface requirements properly across so many organizations and people was a tremendous chore. A single, central management entity is really going to be necessary to ensure that everyone is using the same requirements, that all changes get flowed through, costed out properly, and implemented uniformly, etc. The best example I can think of a system like this is how Boeing managed and integrated the Saturn booster program, despite not actually building much if any of it, or how operations at many/all of the various National Laboratories are subcontracted out. -- Herb Schaltegger, B.S., J.D. Reformed Aerospace Engineer Columbia Loss FAQ: http://www.io.com/~o_m/columbia_loss_faq_x.html |
#120
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MSNBC (JimO) - Hubble debate -- a lot of sound and fury
On Thu, 15 Apr 2004 09:37:15 -0500, in a place far, far away, Herb
Schaltegger made the phosphor on my monitor glow in such a way as to indicate that: Since the CEV appears to be a more modular vehicle, there isn't really any reason to give all of the pieces to one contractor. You may want a prime contractor to oversee everything, but that doesn't mean that entire modules couldn't be subcontracted out. Jeff That approach was tried for SSF. Work Package 1 was all the pressurized elements and internal systems, contracted to Boeing. Work Package 2 was the integrated truss and external systems like the TCS radiators, integration of the PV arrays with the truss and power storage/distribution systems, external GNC stuff, etc, contracted to McDonnell Douglas; Work Package 3 disappeared early on and I can't remember all of what they were to do - earth observation science stuff, I think; WP 4 was solely the external electrical stuff like batteries, power regulators, etc., IIRC. WP1 wasn't really in charge although it was sort of seen as "first among equals." There was (theoretically) a central SSF Program Office at NASA HQ that was in charge but they were far-removed from things happening in the detailed design process and not very effective at all at controlling the various Center contracting offices for the various work packages (which were at MSFC, JSC and Goddard), let alone influencing the contractors directly. The mistake with ISS was not having work packages per se, but in splitting up the NASA management for them (for obvious political reasons, since the primary purpose of the program was to give NASA something to do after the end of the Shuttle development). Multiple contractors could have been managed if they'd had a single government manager. |
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