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#151 2006-01-30 06:50:41

cIclops
Member
Registered: 2005-06-16
Posts: 3,230

Re: Post central for information on CEV IV - Before thread #3 melts down

Astronautix article about CEV. Interesting to read...
http://www.astronautix.com/craftfam/cev.htm

Yes interesting to see a summary of all the different studies that were done, however it misses the point that the main driver for the CEV design is not ISS support but the RTTM mission.


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#152 2006-01-30 07:12:27

GCNRevenger
Member
From: Earth
Registered: 2003-10-14
Posts: 6,056

Re: Post central for information on CEV IV - Before thread #3 melts down

"The selection of an Apollo-type configuration for the re-entry vehicle represented a step back sixty years. The original Apollo design, a NASA in-house concept, was inferior to contractor alternatives. The Soviets selected the Soyuz configuration (identical to the losing General Electric Apollo design) and had a configuration still in production fifty years later...

I think this guy has some really bad case of Russia-worship going on. Just flapping his lips that "Soyuz is way better then Apollo" is stupid, since they were designed to do things differently. Is it lighter? Oh probably, but don't forget that Apollo had to operate two weeks without solar power and carry enough fuel to both brake into and escape from Lunar orbit. If Soyuz carried enough fuel/supplies to do that, it wouldn't be much better then Apollo.

Other alternatives for Apollo were a variety of ballistic, lifting-body and winged configurations, any of which would have provided a fine basis for a manned spacecraft that could be recovered with horizontal landings. At least the excuse given in 1961 - that there was no time to pursue development of a winged vehicle and still make the end-of-the-decade lunar landing deadline - may have had some validity...

This guy is apparently ignorant that neither Apollo era nor modern heat shield materials are capable of withstanding trans-Lunar reentry with wings; the sharp points and flimsy structures would burn right off. Because it requires so many things to go right to enter orbit, rendezvous, and dock then for safety's sake whatever Lunar transit vehicle must have a capability to reenter directly. And if it can do that, then why bother with other methods?

Incredibly, NASA made the same mistake again, fifty years later. The same approach was used. First, proposals from industry were solicited. In both the Apollo and CEV cases these were imaginative, innovative, and incorporated all of the lessons of hundreds of millions of dollars of advanced research funded not just by NASA, but also by industry and the US Air Force. Superior contractor designs using the Soyuz-type separate orbital module or a winged spaceplane approach were made in both cases... This was then suitably tweaked until it will passed the Congressional pork test.

Here we go again with "Russia = Good, NASA = Bad" and "its all about the pork!" blathering... NASA launched the search for a CEV design among contractors before Mike Griffin, the Discovery foam failure, and the hurricanes hit. Griffin correctly surmized that NASA's political capital is more scarce then it was, and for NASA to survive it had to think in terms other then the numbers on the bottom line. Also, all other CEV designs either called for a rocket that was never intended to have man-rated reliability, or else didn't exsist (and was proposed by a pitiful AltSpacer's).

TheStick combined with a updated/uprated Apollo makes sense, since you start with a launch vehicle with man-rated componets. You start with it, and not have to embark on a difficult EELV-upgrade program. We all know what happens to the cost when you try and squeeze tiny amounts of reliability out of a vehicle with such a program (see "Shuttle). The Shuttle SRB is inherintly safer too.

The Apollo capsule is a proven shape, and having only two modules may reduce cost a little since you can reuse more of the vehicle compared to a tripple-module Soyuz too.

After the Apollo decision, it was apparent that a two-man Apollo or Gemini direct lunar mission would have been much more logical, economical, and less risky. In the CEV decision, it was apparent that a design with a re-entry vehicle and service module under 8 tonnes that could be launched by an existing heavy-lift EELV rather than NASA's shuttle-derived hardware would be much more economical. But again the decision was made primarily on political grounds, and to keep NASA government jobs. "

Sure, if all you wanted to do was get there in a big big hurry, turn around, and come home and never go back again.

I don't think its realistic to talk about a CEV vehicle that can blast itself from Lunar orbit back to Earth in only 8MT. And who says the super-duper-safe EELV is going to be cheap versus the historically reliable cost of the SRB? And yes, there are political considerations, that NASA is I think living on borrowed time. If they can't get things going such that they can't be canceld casually, and show that they are competant to do the job, NASA will cease to exsist following the ISS program.


[i]"The power of accurate observation is often called cynicism by those that do not have it." - George Bernard Shaw[/i]

[i]The glass is at 50% of capacity[/i]

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#153 2006-02-03 13:44:58

publiusr
Banned
From: Alabama
Registered: 2005-02-24
Posts: 682

Re: Post central for information on CEV IV - Before thread #3 melts down

I used to think a lot about Mark Wade--but no longer. I like Apollo just fine thank you. He praises that miserable little t/Space contraption that is supposed to be launched by a 747 on stilts by (Forrest) Gump. Please...

Reaction to Wade's nonsense:
http://forum.nasaspaceflight.com/forums … 79&start=1

Super Dave Osborne would have a better chance riding a shell from the Paris Gun than to ride anything Gump builds--like we will ever see it anyway. Rumor has it tha the old OSTP man left for t/Space during the end of O'grief's era, and worked for Gump--who was turned down flat by griffin. After than, he began bashing HLLV, Griffin, the Stick, etc. I defended Griffin in a letter to the Editor to Av Week some months ago, which he didn't like. (We had a private conversation on the topic--where I tried to help the man in suggesting a shoulder-mount AN-225 or 124 would be better than 747.)

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