A Space & astronomy forum. SpaceBanter.com

Go Back   Home » SpaceBanter.com forum » Space Science » Space Science Misc
Site Map Home Authors List Search Today's Posts Mark Forums Read Web Partners

Back to the moon, only CEV reuseable?



 
 
Thread Tools Display Modes
  #1  
Old September 24th 05, 02:25 AM
Philip Walden
external usenet poster
 
Posts: n/a
Default Back to the moon, only CEV reuseable?

Looking at the planned vehicles for the return to the moon, the
article(s) seemed to emphasize leverage of shuttle technology. For
example the use of SSMEs and SSRBs. However, only the CEV was described
as reusable.

Will the new systems also recover and reuse the boosters? If not, seems
like a waste of a good SSME which are supposed to be good for many firings.

  #2  
Old September 27th 05, 04:00 AM
Pat Flannery
external usenet poster
 
Posts: n/a
Default

Philip Walden wrote:

Looking at the planned vehicles for the return to the moon, the
article(s) seemed to emphasize leverage of shuttle technology. For
example the use of SSMEs and SSRBs. However, only the CEV was described
as reusable.

Will the new systems also recover and reuse the boosters? If not, seems
like a waste of a good SSME which are supposed to be good for many
firings.



They did studies on the cost of recovering the SRBs and reusing them vs.
using new-build ones based on the actual costs encountered during the
Shuttle program, it was a bit cheaper to reuse them (I imagine that the
involved inspection process after each flight is fairly expensive), but
not all that much cheaper than using new-build ones.

Pat

  #3  
Old September 27th 05, 04:07 PM
Jeff Findley
external usenet poster
 
Posts: n/a
Default

"Pat Flannery" wrote in message
...
They did studies on the cost of recovering the SRBs and reusing them vs.
using new-build ones based on the actual costs encountered during the
Shuttle program, it was a bit cheaper to reuse them (I imagine that the
involved inspection process after each flight is fairly expensive), but
not all that much cheaper than using new-build ones.


While this may not be such a great thing economically, it's certainly nice
to inspect them after every flight. After the redesigned solid rocket
booster joints started flying (post-Challenger), NASA was able to inspect
those joints after each and every flight to insure that the problem was
really fixed.

If they weren't being reused, there would be economic pressure to not
recover the flown boosters in order to save money. This could result in
disaster if any change in the manufacture of the boosters (intended or not)
started to cause problems, since you might not notice signs of the problem
until another launch vehicle was lost.

Safety is certainly a good reason to keep reusing SRB's, even if it saves
little money to reuse them.

Jeff
--
Remove icky phrase from email address to get a valid address.


..

  #4  
Old September 28th 05, 03:20 PM
Philip
external usenet poster
 
Posts: n/a
Default

Pat Flannery wrote:
Philip Walden wrote:

Looking at the planned vehicles for the return to the moon, the
article(s) seemed to emphasize leverage of shuttle technology. For
example the use of SSMEs and SSRBs. However, only the CEV was described
as reusable.

Will the new systems also recover and reuse the boosters? If not, seems
like a waste of a good SSME which are supposed to be good for many
firings.




They did studies on the cost of recovering the SRBs and reusing them vs.
using new-build ones based on the actual costs encountered during the
Shuttle program, it was a bit cheaper to reuse them (I imagine that the
involved inspection process after each flight is fairly expensive), but
not all that much cheaper than using new-build ones.

Pat

And I guess if I had thought about more, the SSMEs used on the core
boosters are not recoverable from MECO altitude.

Philip

  #5  
Old September 29th 05, 06:26 AM
Pat Flannery
external usenet poster
 
Posts: n/a
Default

Philip wrote:

And I guess if I had thought about more, the SSMEs used on the core
boosters are not recoverable from MECO altitude.



Which makes it strange to use them, as they are not a cheap engine by
any means. I'd have gone with J-2S, despite its lower ISP.
It could be that they are just going to take all the existing SSMEs and
use them up on the stick, figuring that at only one SSME per launch they
will have plenty to work with for a fairly substantial program. Engine
burn time will be a lot shorter in this usage also, so that probably
lowers the level of reliability that an engine is acceptable at,
particularly if they operate at lower than standard thrust.

Pat

 




Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

vB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
Apollo Buzz alDredge Misc 5 July 28th 04 10:05 AM
Apollo Buzz alDredge UK Astronomy 5 July 28th 04 10:05 AM
The Apollo Hoax FAQ darla Misc 10 July 25th 04 02:57 PM
The apollo faq the inquirer UK Astronomy 5 April 15th 04 04:45 AM
The Apollo Hoax FAQ v4 Nathan Jones Astronomy Misc 1 November 5th 03 12:52 AM


All times are GMT +1. The time now is 07:49 PM.


Powered by vBulletin® Version 3.6.4
Copyright ©2000 - 2024, Jelsoft Enterprises Ltd.
Copyright ©2004-2024 SpaceBanter.com.
The comments are property of their posters.