Thrust
Topic Author
Posts: 2585
Joined: Wed Sep 17, 2003 12:17 pm

One Last Saturn V Question

Sat Dec 24, 2011 6:24 pm

I've been trying to figure this out for some time...I'm wondering how much payload the Saturn V theoretically could have lifted into orbit...the reason I ask this was because not only could it get 300,000 pounds into orbit (demonstrated by Apollo 15), but it was capable of boosting its speed an additional 7000 mph to escape earth's orbit. This leads me to wonder how much dry weight the Saturn V could potentially have gotten into orbit if it required the S-IVB to exhaust its entire supply of fuel, of which it could burn six minutes beyond reaching earth orbit. Using just two stages, the Saturn was able to lift 170,000 pounds of dry weight into orbit. It makes me wonder how much larger of a space station it could have launched into earth orbit using all three of its stages.
Fly one thing; Fly it well
 
zanl188
Posts: 3447
Joined: Sat Oct 21, 2006 9:05 pm

RE: One Last Saturn V Question

Sat Dec 24, 2011 8:17 pm

A space station launched into earth orbit using a 3 stage Saturn V would be smaller, in terms of mass, than Skylab, unless you're referring to the wet workshop concept. This is why a 2 stage Saturn V was used.
Legal considerations provided by: Dewey, Cheatum, and Howe
 
prebennorholm
Posts: 6430
Joined: Tue Mar 21, 2000 6:25 am

RE: One Last Saturn V Question

Sun Dec 25, 2011 3:47 am

Things are made to fit for purpose. You cannot just take a three stage vehicle made for escape velocity and load it down with payload to use all three stages for orbit velocity. It would make the take-off weight heavier than what the S-1C stage was designed to handle.

The Saturn V three stage complex would have to be modified to fit as an optimal launcher only to orbit.

It was made to launch into orbit:
- the command module
- the service module
- the moon lander
- the S-IVB stage
- including fuel needed for acceleration to escape velocity.

For the moon landings the S-IVB stage used part of its fuel to reach orbit, then was re-ignited and spent the rest on reaching escape velocity.

So basically the fuel for acceleration to escape velocity could be converted into payload without modifications to the two first stages. For an optimized vehicle that would at least call for an extensively modified S-IVB stage - maybe half size fuel tanks?

I don't have any exact figures, but assuming it correct that Apollo 15 demonstrated 300,000 lbs into orbit, and that was the capability of the Saturn V, then with a modified S-IVB stage it would handle a payload into orbit = 300,000 minus the empty weight of the modified S-IVB stage - we may call that roughly 275,000 lbs.

Maybe there is a more efficient way to convert the Saturn 5 into a heavy weight orbit launcher? It could be a slight reduction of fuel tanks in the S-1C stage and let the S-IVB stage remain unchanged. Same take-off mass but with heavier payload. We need the designers to make any proposals on such modifications.

[Edited 2011-12-24 20:00:24]
Always keep your number of landings equal to your number of take-offs
 
redflyer
Posts: 3882
Joined: Thu Feb 24, 2005 3:30 am

RE: One Last Saturn V Question

Wed Jan 11, 2012 12:08 am

Quoting Thrust (Thread starter):
I'm wondering how much payload the Saturn V theoretically could have lifted into orbit...the reason I ask this was because not only could it get 300,000 pounds into orbit (demonstrated by Apollo 15), but it was capable of boosting its speed an additional 7000 mph to escape earth's orbit.

I'm not a technical sort, but from my layman's perspective it would appear to me that if the Saturn V could put 300k lbs into LEO, then that was how much it could put into LEO. The fact that the 3rd stage carried fuel to push the CSM/LM to escape velocity is moot. It put 300k lbs into LEO, period. Replace the fuel in the 3rd stage with dry material and you still get 300k into LEO.

Quoting prebennorholm (Reply 2):
So basically the fuel for acceleration to escape velocity could be converted into payload without modifications to the two first stages.

And I think that is pretty much what you also stated (if I'm reading what you wrote correctly).
My other home is in the sky inside my Piper Cherokee 180.
 
titanmiller
Posts: 86
Joined: Thu May 25, 2006 2:57 pm

RE: One Last Saturn V Question

Wed Jan 11, 2012 3:32 am

Quoting redflyer (Reply 3):
it would appear to me that if the Saturn V could put 300k lbs into LEO, then that was how much it could put into LEO. The fact that the 3rd stage carried fuel to push the CSM/LM to escape velocity is moot. It put 300k lbs into LEO, period. Replace the fuel in the 3rd stage with dry material and you still get 300k into LEO.

I believe this to be the correct answer.
 
User avatar
kc135topboom
Posts: 11007
Joined: Sun Jan 30, 2005 2:26 am

RE: One Last Saturn V Question

Thu Jan 12, 2012 2:03 pm

Yes, the Saturn-V rocket could lift 300,000 lbs into LEO, and the rocket didn't care if that weight was fuel, or widgets.

Who is online

Users browsing this forum: No registered users and 4 guests