NASASpaceFlight.com Forum
General Discussion => Q&A Section => Topic started by: DaveJ576 on 11/16/2021 02:40 pm
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Does anyone have reliable figures for the total weight (mass) for the S-I and S-IB stages? I am trying to get a handle on how much lighter the Saturn IB first stage was vs. the Saturn I. Popular sources on the net are all over the place or fairly vague.
Thanks
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Have you looked on NTRS? Flight reports produced by MSFC will probably have lots of numbers along those lines. Attached, for example, is the one for SA-201, though you will need to disentangle vehicle mass and S-IB mass.
Also, beware that the first two S-IB stages were really just re-worked S-I stages and were therefore likely heavier than the later units.
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The flight reports as mentioned have detailed mass budgets. Note that each individual Saturn rocket was slightly different and that only the Skylab Saturns flew to consistent orbit insertions. The Block I Saturn I first stages were shorter and lighter than the Block II Saturn I first stages. The early S-IB stages were "leftover" Saturn I stages, so they differed from later S-IB stages, and so on.
Also note that some of the on-line information is based on projected Saturn I(B) types that were under or close to development but that never actually flew. I've posted some Saturn info of this type to the L2 photo threads, but may bring some here if I have time (something I have not had much of lately).
Here, for example, are the SA-10 and SA-208 (Skylab 4) reports. They list the following masses related to the first stages.
SA-10 S-I + Interstage at Liftoff: 448,194 kg
S-I + Interstage at Separation: 53,889 kg
Interstage Mass: 1,095 kg
SA-208 S-IB + Interstage at Liftoff: 448,762 kg
S-IB + Interstage at Separation: 46,279 kg
Interstage Mass: 2,606 kg
- Ed Kyle
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Thank you Ed Kyle, well informed as usual. So they shaved 7 mt out of the S-IB, that's nothing to sneeze at. The mass fraction must have improved markedly (and yes, 1% or 2% by rocket equation standard, is gold).
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Was there any particular reason for the S-IVB coloration changes during the flight series of the Saturn IB? The S-IVB for AS-201 and 202 was markedly different from Apollo 7 and the Skylab vehicles. Was it all about thermal control or was it merely aesthetic in nature?