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#51
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reliability and survivability
Am 14 Sep 2003 15:00:13 GMT schrieb "Rand Simberg":
Why would ANY Ariane be truly and fully man-rated. I can not imagine why this would be done, since it can be hideously expensive to man-rate a vehicle. And since Ariane is first and foremost a commercial launch vehicle, there is no economic incentive (as yet) to man-rate it. [...] That's not man rating a vehicle. That's designing a launch system to accommodate an on-pad abort. I beg to differ. It is (primarily seen) a basic design descision, if a launcher has to be man rated or not. We have not more the 1960's, where you had to take, what already existed, and man-rate it for launching a new type of (this time human) payload. For example the Ariane-4 was never thought to be man rated, because it was INTENDED to be a satellite launcher. OTOH, Ariane-5 was ORIGINALLY intended to be the launcher of the then projected European Hermes space plane (a small shuttle comparable to the actual Japanese project). When the Hermes project was abandoned, the Europeans did not abandon the launcher too, because the payload weight projections for the future showed, that soon would be need for a launcher capable of more than 4.5 metric tons to GTO [that was the Ariane-4 limit]. So they developed (and go on with development) some upper stage variants, that made the original LEO heavy lifter (20-30 ton class) a capable GTO lifter up to about 10 metric tons into GTO. As a conclusion the Ariane-5 can be seen as a principally man rated launcher by design, and it could "relatively" easy re-gain that "award" of actually BEING man rated. cu, ZiLi aka HKZL (Heinrich Zinndorf-Linker) -- /"\ ASCII Ribbon Campaign \ / http://zili.de X No HTML in / \ email & news |
#52
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reliability and survivability
On 14 Sep 2003 19:35:01 GMT, in a place far, far away, Heinrich
Zinndorf-Linker made the phosphor on my monitor glow in such a way as to indicate that: Am 14 Sep 2003 15:00:13 GMT schrieb "Rand Simberg": Why would ANY Ariane be truly and fully man-rated. I can not imagine why this would be done, since it can be hideously expensive to man-rate a vehicle. And since Ariane is first and foremost a commercial launch vehicle, there is no economic incentive (as yet) to man-rate it. [...] That's not man rating a vehicle. That's designing a launch system to accommodate an on-pad abort. I beg to differ. It is (primarily seen) a basic design descision, if a launcher has to be man rated or not. We have not more the 1960's, where you had to take, what already existed, and man-rate it for launching a new type of (this time human) payload. That's the only context in which the term "man rated" makes sense. -- simberg.interglobal.org * 310 372-7963 (CA) 307 739-1296 (Jackson Hole) interglobal space lines * 307 733-1715 (Fax) http://www.interglobal.org "Extraordinary launch vehicles require extraordinary markets..." Swap the first . and @ and throw out the ".trash" to email me. Here's my email address for autospammers: |
#53
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reliability and survivability
[I've clipped the attributions, because I'm not sure who said what,
except that Rand said the second. Or something like that.] Another area of man-rating involves modifying/adding avionics to enable health-monitoring of the crew. I've been told that that is NOT as easy or cheap as it may sound! That's the only vehicle change that I could see being worthwhile to add. What does "health-monitoring of the crew" mean in practice? Pulse rate and blood pressure would seem to be easy enough. General activity ditto. At least crude real-time EKG and EEG might be done with a bit more invasiveness, but not a lot. Wireless to get it to the ship systems and back to the ground. |
#55
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reliability and survivability
In sci.space.policy Bent C Dalager wrote:
In article , The Ruzicka Family wrote: Why would ANY Ariane be truly and fully man-rated. I can not imagine why this would be done, since it can be hideously expensive to man-rate a vehicle. And since Ariane is first and foremost a commercial launch vehicle, there is no economic incentive (as yet) to man-rate it. The question is whether Ariane is first and foremost a project based on economics or a national prestige project. If it's the latter, then it wouldn't really matter how expensive it would be or whether or not man-rating would be useful in any way. But I don't think Ariane is foremost a national prestige project. So instead of man-rating, the next step will be Ariane 5 ECA. Cheers Bent D -- Sander +++ Out of cheese error +++ |
#56
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reliability and survivability
Heinrich Zinndorf-Linker wrote: As a conclusion the Ariane-5 can be seen as a principally man rated launcher by design, and it could "relatively" easy re-gain that "award" of actually BEING man rated. But the Hermes aspect got dropped well before the first one was built, were any of the man-rated design safety criteria relaxed in the interests of weight reduction and economy in the finished vehicle? Pat |
#57
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reliability and survivability
Rand Simberg wrote: I think that he meant health monitoring the vehicle, so you know ASAP whether or not to abort. That would make a lot more sense, although monitoring the crew's health would probably allow one to know to the second when the **** hit the fan. Pat |
#58
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reliability and survivability
In sci.space.policy Pat Flannery wrote:
Rand Simberg wrote: I think that he meant health monitoring the vehicle, so you know ASAP whether or not to abort. That would make a lot more sense, although monitoring the crew's health would probably allow one to know to the second when the **** hit the fan. But that would be too late for teh crew. Given the extremely low tolerance level for losing crews, you need to know well in advance to anything that would sigifcantly affect crew health readouts, or you won't have time for counteraction. Pat -- Sander +++ Out of cheese error +++ |
#59
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reliability and survivability
Sander Vesik wrote: But that would be too late for teh crew. Given the extremely low tolerance level for losing crews, you need to know well in advance to anything that would sigifcantly affect crew health readouts, or you won't have time for counteraction. I should have stuck a "wink" on that one... I wasn't being completely serious. Pat |
#60
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reliability and survivability
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