Author Topic: What would a better Saturn V/Lunar Program have looked like?  (Read 13085 times)

Offline Lobo

  • Senior Member
  • *****
  • Posts: 6758
  • Spokane, WA
  • Liked: 555
  • Likes Given: 348
 What would a better Saturn V/Lunar Program have looked like?

Yet another hypothetical, and intellectual exercise.

Weíve explored what a better STS would have looked like, and what if Apollo/Saturn had never been cancelled.  However, the problems with Saturn that lead to the hope of a cheap/reusable STS (which didnít exactly pan out, obviously), were because of the huge costs of the Saturn V system.

As I understand, a monolithic in-line system like the Saturn V was the most simple, most reliable heavy lifter if you are starting from a clean sheet design like NASA was in the 60ís.  If they were to go to the moon, they needed a new rocket.  And Monolithic inline has the fewest elements doing the least amount of staging.  Fewer, but large, engines mean the most reliable/simple MPSís on the stages.  Each stage only has one LOX tank and one fuel tank, so itís the most mass and volume efficient design.
I think this was a lot of the reason this system was chosen for Saturn V, and why the RAC-2 studies looked so tempting for SLS.

However, it has some drawbacks.  None of the elements would be shared by any other launcher, so NASA bore all the development and overhead expenses 100%.  Itís good at launching heavy loads, but not so good at scaling back to intermediate loads.  INT-20 and INT-21 made for some interesting concepts, but they still werenít great ways to scale down.  INT-21 actually was pretty good for a fairly heavy LEO launcher.  INT-20 had a much too powerful first stage for itís S-IVB upper stage.  Saturn II concepts needed either new S-II engines, or SRBís to just get off the ground. 

So thereís 3 whole stages, and two different engine lines that would be used for nothing else that NASA would need to maintain.  When the Apollo money was rolling in, they were flush with cash and money was no object.  So for this exercise, letís assume that some bright bulbs in NASA decided to conceive a system that would be sustainable in the long run after the Space Race was won, and they understood that level of funding wouldnít be around after that.  So instead of the mightly monolithic inline Saturn V, something else was conceived that would have still got us to the moon before January of 1970.  Maybe that would be utilization of existing assets in the Titan-III of that time to have the least development and most cost sharing with USAF, or maybe it would be new engines and rockets, but in parallel staged configurations that would have been cheaper to maintain, and had a higher production rate, and NASA could have afforded after the Space Race was won.  So perhaps some of the concepts talked about in the ďWhat if Saturn have never been cancelledĒ thread, like multiple 6.6m kerolox cores strapped together?
Or maybe it would be a combination of both.  A smaller kerolox or hydrolox first stage with multiple Titan III SRBís strapped to it, and an S-IV type upper stage/EDS?
But keep it all in the technology and knowledge of the time.  Space travel was brand new, and Gemini was the testbed for technologies that were co-currently being developed for Apollo as Apollo and Saturn and the LEM took shape.  We didnítí even know if we could do an EOR or docking in space until we did it during Gemini.  We know today we could do complex in orbit assembly, and probably could mount a lunar program all based on small EELV/Titan-III class launchers, and propellant transfer.  But that would have been a real unknown back then.  So any system alternative could probably have some of that, but not too much. 
And whatever it is, would also need to be useful in the pre-Apollo 8 test flights like the Saturn 1B was, and useful in the post-Apollo 17 back-to-LEO NASA Era that would have been potentially affordable enough that STS wouldnít have had to be conceived.  Maybe even Apollo 18, 19, and 20 could have flown under the budget cutbacks with the budget savings?

So in short, how could we have gotten to the Moon by December of 1969 in a cheaper and more sustainable way, that could have then carried on past Apollo 17, eliminating any HSF gap, and then dovetailing into a 70ís and 80ís new focus for NASA which was basically LEO space stations?  (although STS was so expensive, that basically got put on hold for two decades outside of Skylab)

Myself, Iím thinking about a 6.6m-ish hydrolox first stage, that would be basically a stretched version of the S-IV, with an S-IV on top.  Both powered by J2ís.  Then multiple Titan-III SRBís around it sufficient to get around 120mt to LEO.  The core stage could even be lit after takeoff like Titanís core was, as the J2ís had to be developed to air-start to be an EDS.  A cluster of 3-5 on the first stage (whateverís required depending on fuel load and when theyíd ignite), and one on the upper stage.  RL-10ís could be used on the S-IV-like upper stage as well, as they already existed and could have been used without the need for a 2nd engine development program. 

So, one production line turning out two length cores of the same diameter.  One new hydrolox engine development program.  Use of existing Titan IIIC SRBís (available by 1965), so no new development there.  Titan SRBís were used all through the 60ís, 70ís, 80ís and 90ís so theyíd have been available for a lot of NASA history, and NASA could have updated their core when USAF upgraded SRBís along the way.  The LV is scalable by the number of SRBís attached to it, so it could do more medium lift configurations, as well as heavier lift ones. 
If you couldnít fit enough SRBís on it to get a Saturn V class payload to LEO for a single launch Apollo lunar architecture, then a two launch architecture with EOR and then Apollo LOR could be done.  Lauch of the LEM and EDS from Pad 39A, and Launch of Apollo CSM from Pad 39B, within perhaps hours or a day of each other.  EOR, Apollo docks in the same position on the LEM in the cradle on the S-IV that it was for Apollo TLI, and then the TLI burn is done. 
If two launches are required, then that does add an extra element to the mission.  But the mission already depended on LOR.  At least a failed EOR wouldnít result in LOC like a failed LOR would haveÖ.two of the crew anyway.  So I donít think that would have been a major problem by 1969, and KSC has two pads and could accommodate two launches in a short time frame.  The VAB certainly could have processed two LVís at once, so not real problem there. 

After Apollo 17, Skylab still could have been built from an S-IV hull.  A Skylab two could have used two or three similar modules attached to a central hub.  It might need to be launched on top of the S-IV upper stage to get it into LEO.  But again, shouldnít be a problem.  Apollo CSM could have been continued and refined for space station taxi service.

Although itís not as sexy as the Shuttle, the Russians have been flying Soyuz and Proton in one form or another since the lat 1960ís, and theyíve never had a HSF gap like we have.  So thereís something to be said for simple, cheap, easy, and reliable. 

But there might be better ideas out there.  What do you guys think?

Offline RanulfC

  • Senior Member
  • *****
  • Posts: 4445
  • Heus tu Omnis! Vigilate Hoc!
  • Liked: 806
  • Likes Given: 32
Good one... Again :)

Given the "restrictions" I'll have to think about it a bit before digging in but I think I'll take a "swing" at part of the post:
Quote from: Lobo
Although itís not as sexy as the Shuttle, the Russians have been flying Soyuz and Proton in one form or another since the lat 1960ís, and theyíve never had a HSF gap like we have.  So thereís something to be said for simple, cheap, easy, and reliable.
... And they haven't ever gone to the Moon either so that's something to consider. They also "saw" the need for a massive, and expensive HLV for about the same "reason" the US did.

Despite being "simple, cheap, easy, and reliable" and while they built several Earth-Orbit Space Stations over the decades, up to Mir they still hadn't "quite" found it "sustainable" enough over the long run to utilize the system to develop and deploy anything for manned flight beyond LEO.

While it is true the Russians never had the HSF "gaps" the US did, neither for the most part did they seem to take HSF or "space" seriously to the extent that the US did at the time.

It's always actually "amazed" me that the Russians have NOT gone to the Moon given the way they built a "workable" system around Soyuz-Proton. During the "gap" between Apollo and Shuttle I could have seen them putting their steady and increasing space experiance to work to push a modular mission to the Moon having their crew(s) stay longer than ours to prove the "point" :)
(After all the rhetoric was that they would always out "last" a capitalist system :o)

But they couldn't. Various factors, (lack or political, financial support, etc...) combined to keep them from starting "another" space-race and that "battlefield" was set aside until much, much later. And even today though Russians continue to fly into space they've scaled back their operations greatly and in a great part it's because their system may be "simple, easy, and reliable" but I don't think its really all that "cheap" and it still requires a huge amount of infrastructure and people to keep running. Worse yet it actually had a few "advantages" over the NASA/Apollo program in that part of it was paid for by the military for their use and though it was quickly made "obsolete" for military use and devoted to just launching payloads it STILL isn't "cheap" enough or "mass-produced" enough to really gain any advantages.

I'm "guessing" that says something about the long term viability of the system and "way" that payloads in general and HSF in particular is "done" that needs some fundamental re-examination... But that's ANOTHER topic :)

Looking at what we "know" now versus what people "knew" then I think we're going to be hard pressed to NOT come out to the exact same conclusions under the cited circumstances without a serious amount of hand-waving to get the "results" we want :)

Randy
From The Amazing Catstronaut on the Black Arrow LV:
British physics, old chap. It's undignified to belch flames and effluvia all over the pad, what. A true gentlemen's orbital conveyance lifts itself into the air unostentatiously, with the minimum of spectacle and a modicum of grace. Not like our American cousins' launch vehicles, eh?

Offline Proponent

  • Senior Member
  • *****
  • Posts: 5587
  • Liked: 1135
  • Likes Given: 682
Of course, we now know that while the Soviets were actively conducting the Salyut/Mir program, they were also developing Buran and Energia.  That must have cost a lot money and would have made it difficult to pursue a manned lunar program.  Maybe if they hadn't decided to spend so much money on the big rocket, the might have been able to use their smaller rockets to go to the moon (this sounds depressingly familiar...).
« Last Edit: 10/15/2012 09:14 PM by Proponent »

Offline IRobot

  • Full Member
  • ****
  • Posts: 1295
  • Portugal & Germany
  • Liked: 293
  • Likes Given: 259
I would just upgrade the RP1-LOX engines for better ISP and either reduce the overall size, maintaining LEO payload or maintaining the size and increasing the payload.

In terms of purpose, I think the best would be to build the ISS with some Skylab size elements. Four-five launches would be enough.

Offline Lobo

  • Senior Member
  • *****
  • Posts: 6758
  • Spokane, WA
  • Liked: 555
  • Likes Given: 348
Of course, we now know that while the Soviets were actively conducting the Salyut/Mir program, they were also developing Buran and Energia.  That must have cost a lot money and would have made it difficult to pursue a manned lunar program.  Maybe if they hadn't decided to spend so much money on the big rocket, the might have been able to use their smaller rockets to go to the moon (this sounds depressingly familiar...).

Yea, itís hard to really compare exactly our program and the Russians.  We had a lot more actual money to spend, and a greater array of expertise, brain power, and advanced technology than the Soviets did.  Some of that was their economy, some of it was their closed society that (IMO) would have made it tougher for some of their best and brightest to work their way into a position where they could have contributed to the Soviet effort.  So I think they were working from a more limited pool than we were, with more limited resources.  As I understand, they couldnít build large cylindrical cryo tanks, so their big tanks for N-1 had to be spherical, which was limiting in geometry.  And they didnít have really much knowledge in hydrolox propulsion, so they tried to do everything in kerolox, which made their upper stages far less performing. 
I think they had a pretty huge investment in N-1, and then couldnít get it flying so all of that time and resources were sort of wasted.  And then again later with Energia/Buran.  They just didnít have the resources to sustain such an expensive system along with their normal expendable launches.  Even more so as the Soviet Union started to crumble in the late 80ís.   There was nothing wrong with Energia, but it sort of ended up being another big, expensive heavy lifter that never really did anything.  Those two programs, and the timing of them, might have been what kept the Soviets from trying to get to the moon later.  If they hadnít been trying to get Energia to launch a Soviet Shuttle for military parody (the main goal of Buran I think), and focused on using Energia to be an inline heavy lifter launching a lunar capable soyuz and updated LK lander, maybe they could have gotten there in the 80ís?  Energia with an EDS could have certainly performed the mission, and the hydrolox core showed by the 80ís the Soviets could do hydrolox, something they couldnít do in the 60ís. 

Dunno, probably lots of reasons.  Heck, we might not have gotten there if the Soviets actually had beaten us.  Political support could have dried up for it.  Although maybe NASA would have then been focused to going to Mars or something, to get a different ďfirstĒ for America.  Who knows?

Offline Lars_J

  • Senior Member
  • *****
  • Posts: 6161
  • California
  • Liked: 665
  • Likes Given: 195
It seems like the best way to build a Saturn V like LV on the cheap would be to have a heavy and intermediate launch vehicle using the same components. In this case the 1st stage and heavy boosters would be a 6.6m diameter RP core powered by two F-1. The second stage would be the S-IVB stage as is.

Offline Lobo

  • Senior Member
  • *****
  • Posts: 6758
  • Spokane, WA
  • Liked: 555
  • Likes Given: 348
Good one... Again :)

... And they haven't ever gone to the Moon either so that's something to consider. They also "saw" the need for a massive, and expensive HLV for about the same "reason" the US did.

Despite being "simple, cheap, easy, and reliable" and while they built several Earth-Orbit Space Stations over the decades, up to Mir they still hadn't "quite" found it "sustainable" enough over the long run to utilize the system to develop and deploy anything for manned flight beyond LEO.

While it is true the Russians never had the HSF "gaps" the US did, neither for the most part did they seem to take HSF or "space" seriously to the extent that the US did at the time.


I didnít mean to imply the Russians did everything better.  They had achievements, and so did we.  We accomplished more technological achievements like a super heavy lift vehicle, landing on the moon, and building a big reusable space plane.  They got a man into space first (barely), but into orbit too, which we didnít do until John Glenn.  They did a space station before we did.  They did in-orbit assembly of a space station before we did.  And they maintained HSF capabilities pretty much unbroken since the mid 60ís. 
Just saying there can be things to learn from them too.


It's always actually "amazed" me that the Russians have NOT gone to the Moon given the way they built a "workable" system around Soyuz-Proton. During the "gap" between Apollo and Shuttle I could have seen them putting their steady and increasing space experiance to work to push a modular mission to the Moon having their crew(s) stay longer than ours to prove the "point" :)
(After all the rhetoric was that they would always out "last" a capitalist system :o)

But they couldn't. Various factors, (lack or political, financial support, etc...) combined to keep them from starting "another" space-race and that "battlefield" was set aside until much, much later. And even today though Russians continue to fly into space they've scaled back their operations greatly and in a great part it's because their system may be "simple, easy, and reliable" but I don't think its really all that "cheap" and it still requires a huge amount of infrastructure and people to keep running. Worse yet it actually had a few "advantages" over the NASA/Apollo program in that part of it was paid for by the military for their use and though it was quickly made "obsolete" for military use and devoted to just launching payloads it STILL isn't "cheap" enough or "mass-produced" enough to really gain any advantages.


Iím not for sure, but I think after they couldnít get the N-1 flying and lost the race to the Moon with us, they shifted focus to their LEO space station program.  Rather than arriving late to the Moon, with an inferior lander and capability to us.  Iíd imagine thereís some politics in that, and they new even if N-1 got flying, it couldnít put two crew and a lander the size of the LEM on the surface. 


Looking at what we "know" now versus what people "knew" then I think we're going to be hard pressed to NOT come out to the exact same conclusions under the cited circumstances without a serious amount of hand-waving to get the "results" we want :)


Well, obviously any of these hypothetical questions sort of assume that someone back then would have had the foresight/intuition, to have seen some of the problems we now realized in hindsight. 
As probably the SLS RAC-2 team found out, a big, monolithic in-line rocket is one of the fastest and most reliable and efficient ways to get a payload of a certain size into space for all the reasons I stated in my genesis post.  Especially when starting from scratch as Apollo was and as the RAC-2 team was assuming in their studies. 
But a big monolithic in-line can not be as ďpracticalĒ a way to do it from the standpoints of launching anything other than your super heavy payload and cost sharing of systems and components, as some other systems.

So back in the early 60ís, a fledgling NASA whoíd been beaten by the Soviets into space, had a mandate from a popular president, cold war politics, basically a blank check for funding, and very little knowledge of the challenges and complexities they would face.  A monolithic in-line is very simple, and making it large enough to do the entire mission in one launch reduces mission complexity.  Iím sure it seemed like the most logical choice.

But what if someone had the intuition to fear a budget axe falling after they achieved their goal, and the political forces werenít backing them any more?  And he didnít want to be stuck with this giant, expensive rocket that really wasnít affordable without that big budget and a mission of doing lunar landings?  And wanted something that could get us to the moon by 1969, but also would be affordable after that too?
Thatís kind of the the hypothetical here.  So yea, this thread needs to take some creative liberties to set up a scenario that someone might have thought beyond the most direct way to get from point A to point BÖ.something that could also get to point C afterwards.  ;-)

Offline Lobo

  • Senior Member
  • *****
  • Posts: 6758
  • Spokane, WA
  • Liked: 555
  • Likes Given: 348
It seems like the best way to build a Saturn V like LV on the cheap would be to have a heavy and intermediate launch vehicle using the same components. In this case the 1st stage and heavy boosters would be a 6.6m diameter RP core powered by two F-1. The second stage would be the S-IVB stage as is.

Yea, I had this thought too.  Build that 6.6m mono-core kerolox booster, using either F-1 or H-1 engines.  And strap 3 or 5 of them together for a heavy lift first stage.

However, if you are going to the moon, then you need an EDS.  A multi-core first stage using a gas generator (low ISP) engine would be limited once it got past the lower ascent, wouldnít it?  Could an S-IVB stage make up the difference, and then also to the TLI burn?  In Saturn, the S-II did most of that upper ascent.  The S-IVB didnít have to do a whole lot in addition.  Wouldnít a multi-core first stage kerolox GG only be useful to about the altitude the S-IC was?  And if you need two more stages on top like the S-IC did, then what have you gained?  Other than a bit more scalable system.

Thatís why I thought of the two hydrolox stages both based off the S-IV stage.  So hopefully itís not quite like developing two new stages completely from scratch the way the 3 Saturn V stages were developed from scratch.  Hopefully development of these two 6.6m hydrolox stages would be more like developing ď1.5Ē new stages.  ;-)

And then for the ďfirstĒ stage, the existing Titan IIIC SRBís would be used, so no development needed, and no need to support that production by NASA alone. 
Iíd picture the stretched hydrolox core to look a bit like the Delta II first stage with itís ring of SRBís around it, in itís heaviest lift configuration.  It would have less SRBís, and the core would do more of the initial ascent for the medium lift configurations.

Offline ARD

  • Member
  • Posts: 72
  • Liked: 0
  • Likes Given: 0
Way I see it, a kerolox core, 6.6 meters across with a set of uprated H-1 engines, and a hydrolox stage (J-2) on top, is the way to go.  Lash 3, 4, or 5 of those together and you get the capability of a Saturn V (or at least an INT-20) with little hardware that you wouldn't have for purely LEO or space station resupply missions.  The H-1 engines can see some use on smaller LVs--apparently, those were used on Deltas in the 1970s.  You have this way only two engine production lines, one of those also supplying engines for DoD and smaller unmanned missions. 

Basically, my suggestion is Falcon Heavy (or Atlas Phase II), but with a somewhat stretched Saturn IB as the starting point. 

Offline Lobo

  • Senior Member
  • *****
  • Posts: 6758
  • Spokane, WA
  • Liked: 555
  • Likes Given: 348
Way I see it, a kerolox core, 6.6 meters across with a set of uprated H-1 engines, and a hydrolox stage (J-2) on top, is the way to go.  Lash 3, 4, or 5 of those together and you get the capability of a Saturn V (or at least an INT-20) with little hardware that you wouldn't have for purely LEO or space station resupply missions.  The H-1 engines can see some use on smaller LVs--apparently, those were used on Deltas in the 1970s.  You have this way only two engine production lines, one of those also supplying engines for DoD and smaller unmanned missions. 

Basically, my suggestion is Falcon Heavy (or Atlas Phase II), but with a somewhat stretched Saturn IB as the starting point. 

See my previous post.  I think what you describe would be a good LEO heavy lifter, but the idea of this thread is to go to the Moon.  How much of the ascent can the low ISP (gas generator) cluster of 6.6m kerolox cores do?  The S-IC was this, just in a wide-body version.  It burnt for 150 seconds.  But the entire burn to LEO was 675 seconds (over 11 minutes) when you add the S-IC, S-II and S-IVB first burn up. 

The Falcon 9ís gas-generator first stage burns for 170 seconds.

So how long of a burn do you think this cluster of 6.6 kerolox gas-generator engine cores youíll get?  Iím no rocket scientist, but I think probably much beyond the burn time for the S-IC or F9, your performance starts dropping off considerably.  Staged combustion kerolox will get a longer useful 1st stage burn, but I donít think we had any at that time.  Just the Soviets. 
And even then, the Atlas Vís staged combustion engine burns for 253 seconds, still requiring a considerable burn from Centaur to just get to LEO.  The S-IVB stage only needed to do 165 second burn to get to orbit. 

(although perhaps with cross feed, such an LV could get a longer burn out of the first stage...but cross feed would add complexity to this new LV in the 1960's...)
Iím just thinking if you are trying to get to the Moon, an upper stage on a gas-generator kerolox engine that could do both the 2nd stage ascent as well as the TLI burn would be very large.  It would be something like the S-II and S-IV stage combined in one for a Saturn V class LV.    I think thatíd be some big mass penalties for the TLI burn.
Thatís why Iím not so sure thatíd be the best way to go. 
So my concept is to have a sustainer hydrolox stage, either ground lit, or air lit. (a J2 could do either).  Let the solids do the initial heavy lifting and the core burn almost to orbit.  Then the S-IV stage can do the last part of the ascent, and the TLI burn as it did for the Saturn V. 
Then the H-1 and then F-1 are never developed.  The H-1 was later used for Delta in the 70ís, but (according to Wikipedia anyway), the H-1 was developed specifically for Saturn 1.  The F-1 was developed for Saturn V.  My concept eliminates both of those development programs.  RL-10 already exists, as does Titan SRBís.  NASA need only develop J2 for this concept.  ď1.5Ē new stages and 1 new engine.  I think thatíd beat Saturnís 3 new engines and 4 new stages (between Saturn 1 and Saturn V) anyway.

Perhaps some people with more knowledge on this could weigh in?

Offline Lars_J

  • Senior Member
  • *****
  • Posts: 6161
  • California
  • Liked: 665
  • Likes Given: 195
It seems like the best way to build a Saturn V like LV on the cheap would be to have a heavy and intermediate launch vehicle using the same components. In this case the 1st stage and heavy boosters would be a 6.6m diameter RP core powered by two F-1. The second stage would be the S-IVB stage as is.

Yea, I had this thought too.  Build that 6.6m mono-core kerolox booster, using either F-1 or H-1 engines.  And strap 3 or 5 of them together for a heavy lift first stage.

However, if you are going to the moon, then you need an EDS.  A multi-core first stage using a gas generator (low ISP) engine would be limited once it got past the lower ascent, wouldn’t it?  Could an S-IVB stage make up the difference, and then also to the TLI burn?  In Saturn, the S-II did most of that upper ascent.  The S-IVB didn’t have to do a whole lot in addition.  Wouldn’t a multi-core first stage kerolox GG only be useful to about the altitude the S-IC was?  And if you need two more stages on top like the S-IC did, then what have you gained?  Other than a bit more scalable system.

Well clearly if you are looking for a more affordable system with fewer components, then you might not get Saturn V performance, and so your lunar landing strategy might not favor LOR.

As for a TLI burn - my suggestion would be to put a shortened S-IVB as a 3rd/TLI stage for lunar missions. Same tooling and engine as S-IVB.

So with two engines (F-1 and J-2), and one tank tooling (6.6m), you could lift anything from 25t with a single stick, to 85t for heavy variants (or perhaps significantly more). Costs could be brought down by mass-production of the above elements. (BTW my performance numbers are just guesstimates, feel free to correct)
« Last Edit: 10/16/2012 03:08 AM by Lars_J »

Offline RanulfC

  • Senior Member
  • *****
  • Posts: 4445
  • Heus tu Omnis! Vigilate Hoc!
  • Liked: 806
  • Likes Given: 32
Don't forget that the biggest "hold-up" on the whole Apollo program was the decision on the "how" and it came down in the end to "making" the deadline or not. EOR was the 'prefered' method for all the "space" advocates inside and outside NASA, but the overall "timeline" meant it wasn't going to be done in less than a decade. After that it was either direct or LOR and direct simply needed TOO big a rocket to do.

Given "some" flexability and less "pressure" I'm pretty sure that some sort of EOR operation would have won out in the end. If there had been serious development issues with the Saturn-V and an up-rated and more "modular" Saturn-1 had been needed and developed you probably have a really good start on a flexible space transport system. However, (again) its a "NASA only" booster so there would be a cost to figure in. (Anybody come up with a GOOD reason for a manned military presence in space? The DoD/AF have been trying for years but no joy... Now if they could somehow "convince" the "powers-that-be" and THEY needed a Saturn-1 class booster you've got some good traction started... :) )

Reusabilty would always be in the "back" of everyones mind so you'd see work begun on trying to recover the Saturn-1 booster and later probably some sort of recoverable and reusuable upper-stage and/or vehicle. But if the flight rates never allowed the cost savings to appear overall the program cost might not be so bad.

Randy
From The Amazing Catstronaut on the Black Arrow LV:
British physics, old chap. It's undignified to belch flames and effluvia all over the pad, what. A true gentlemen's orbital conveyance lifts itself into the air unostentatiously, with the minimum of spectacle and a modicum of grace. Not like our American cousins' launch vehicles, eh?

Offline Lobo

  • Senior Member
  • *****
  • Posts: 6758
  • Spokane, WA
  • Liked: 555
  • Likes Given: 348

Well clearly if you are looking for a more affordable system with fewer components, then you might not get Saturn V performance, and so your lunar landing strategy might not favor LOR.

As for a TLI burn - my suggestion would be to put a shortened S-IVB as a 3rd/TLI stage for lunar missions. Same tooling and engine as S-IVB.

So with two engines (F-1 and J-2), and one tank tooling (6.6m), you could lift anything from 25t with a single stick, to 85t for heavy variants (or perhaps significantly more). Costs could be brought down by mass-production of the above elements. (BTW my performance numbers are just guesstimates, feel free to correct)

While this would be more scalable than the Saturn V, itís still basically 3 stages, even though the 6.6m upper stage and S-IV stage could share the same production line, as in my concept.  So weíll call it ď2.5Ē new stages.  And two new engines.  Not sure if it gains much (or any) development savings over Saturn V (if we exclude Saturn 1B)?

Offline Lobo

  • Senior Member
  • *****
  • Posts: 6758
  • Spokane, WA
  • Liked: 555
  • Likes Given: 348
Ok, so looking at my concept a bit more, a few assumptions.

1)   EDS with roughly the same performance as the S-IVB stage.
2)   Hydrolox core stage with roughly the same capacity and performance of the S-II stage.
3)   8 Titan IIIC SRBís can roughly approximate the performance of the S-IC stage.

#2 might mean the core needs to be a little wider than 6.6m.  Perhaps 7-8m.  The EDS would then be wider and shorter than the S-IV stage, as the idea is they share the same production line. 

So, for a 1-launch architecture:

The Titan UA1205 SRB available in 1965 had about 1.3M lb thrust, and 115 seconds of burn time.  Six of them is about equal in thrust to the S-IC stage, but these SRBís are heavier, lower ISP and donít burn for quite as long. (S-IC burned for 150 seconds).  Weíll assume 8 UA1205 SRBís to make up that difference.  Geometrically, they should fit around the core ok.  The core might even need to hold a little more hydrolox than the S-II to make up the burn length difference, but thatís really not a problem.  The core will be designed from scratch (just as the S-II and S-IC were) and can be whatever it needs to be. 
So, if the core has  a cluster of 5 J2 engines, and they air start after SRB separation, just as they did after S-IC separation, then the core basically performs the S-II burn.  And the EDS performs the S-IVB burns with a single J2.
Since we are following the performance of the Saturn V, and we know what it could do, it can be roughly extrapolated to say this could then lift roughly the same payload to LEO and TLI as Saturn V.

Some issuesÖ
Would 8 SRBís burning cause any problem to the non-burning cluster of five J2ís?  Could the SRB nozzles be lowered  below the core engines a bit to compensate if so?
And because the SRBís canít throttle down, would there be too many gís pulled with that many SRBís burning?
Maybe my assumptions about 8 SRBís approximating the S-IC is incorrect.

If those issues proved to problematic, a two launch solution could be done.

Using this data as a reference:

http://www.friends-partners.org/partners/mwade/lvfam/saturnii.htm

It looks like my concept with four UA1205 SRBís could get almost 52mt to LEO, assuming the core is roughly the performance and capacity of the S-II.  Thatís a bit lean for the latter Apollo missions, so perhaps a 6 SRB launch to launch the LEM and the fueled EDS, and then Maybe another launch without the EDS, letting the core put the Apollo CSM into orbit for EOR with the LEM/EDS.  Looks like some of the Saturn II configurations with Titan SRBís didnít even need the S-IVB stage to put payloads in LEO.  IT just needs to get about 30mt to LEO for the fully fueled Apollo CSM.  It lists a variant with just the S-II stage and four SRBís getting 39mt to LEO, so it looks like thatíd work with a core-only stage for Apollo.

Both stacks are rolled out to Pads 39A and 39B.  The EDS/LEM is launched first into a parking orbit and checked out.  If everything is ok, then the crew is launched from the other pad for EOR.  Once Apollo CSM docks on the LEMís docking port, the EDS does the TLI burn, and everything else is just like how all the Apollo missions actually went down. 

I think that would work out ok.  Itís only adding in one element over Saturn V, which is the EOR. 

Again, the advantages is a pretty scalable system, only one engine to develop, and ď1.5Ē stages to develop.  It can put up pretty sizable LEO payloads in a single launch, such as large space station modules, post-Apollo.  However, just the core along with probably 2 SRBís should get S-1B sized payloads into LEO for Space Station Taxi.  So that wouldít be a very expensive LV to launch and maintain.  The EDS could actually be shelved during the post Apollo era, if it wasnít needed, but since the same production line that makes it is still making the hydrolox core, it could be made again any time it was required for a mission. 

This LV would always need at least two Titan SRBís to launch, as it canít get itself off the ground otherwise, obviously.   Like the Saturn II. 

So I guess, in short, this concept is the Saturn II concept, just with the EDS and core sharing a production line, and the core being design from the jump to mount combinations of Titan SRBís, where the S-II in the Saturn II concept wasnít and would have had to be redesigned.  This saves the development of the H-1, the F-1, the S-1B and the S-IC.  One engine and two stages. To develop.  And one engine and one stage production line to maintain.

I am probably overlooking something pretty important with this concept, but what?  Otherwise, it seems pretty practical. 

Offline Proponent

  • Senior Member
  • *****
  • Posts: 5587
  • Liked: 1135
  • Likes Given: 682
As background to the topic at hand, allow me to point out the Army's 1960 study "A Lunar Exploration Program Based upon Saturn-boosted Systems."  As far as I know it's the most detailed look in the early-1960s at lunar missions involving more than two launches.  A number of scenarios are discussed, but the preferred one, diagrammed on PDF p. 262, involves six launches of an 80,000-lb-class launch vehicle (equivalent to the Saturn C-3, though that's not quite the configuration shown in this study): five tanker launches plus one for the spacecraft.  The spacecraft landed directly on the moon, carried two astronauts, and was hydrogen-fuelled.  Make what you want of the weight estimates.  On the one hand, the a weight savings could have been made by using LOR rather than a direct landing.  On the other hand, 1) early 60s weight estimates were often on the optimistic side (John Houbolt thought one C-3 would suffice for LOR with a crew of three!), 2) replacing lox/hydrogen with hypergols increases weight, and 3) so does increasing the crew from two to three.

The study also claims that if the workhorse launch vehicle had a capacity of less than 45,000 lb to LEO, then not just re-fuelling but also assembly would be required in LEO.  Forty-five thousand pounds was about the capacity of the proposed Saturn C-2, but in this study it was the Saturn B-1 (with a lox/RP-1 second stage) that was under consideration.

There's another study, done shortly after NASA was assigned the moon mission, that compares several approaches, including, IIRC, orbital assembly or re-fuelling based on Saturn C-3s, EOR, LOR and direct, that's quite interesting.  Unfortunately, I don't have access to it at the moment.

Offline Proponent

  • Senior Member
  • *****
  • Posts: 5587
  • Liked: 1135
  • Likes Given: 682
Now if they [USAF] could somehow "convince" the "powers-that-be" and THEY needed a Saturn-1 class booster you've got some good traction started..

The Air Force did convince the powers that be that it needed the Titan III-C, which was in the same class as the Saturn I (though somewhat smaller than the Saturn IB, or course).  I think there could have been an opportunity there to have a Saturn I-class booster used by both the Air Force and NASA.  As it was, there were some fierce arguments between the Titan III-C and Saturn camps.  There's an interesting Titan III history that's been posted somewhere on this site (by Blackstar?).  The Air Force was claiming at one point, for example, that the Saturn's 8-engine cluster was so complex that it wasn't clear it would ever work, let alone be reliable.
« Last Edit: 10/17/2012 02:21 PM by Proponent »

Offline Lobo

  • Senior Member
  • *****
  • Posts: 6758
  • Spokane, WA
  • Liked: 555
  • Likes Given: 348
Now if they [USAF] could somehow "convince" the "powers-that-be" and THEY needed a Saturn-1 class booster you've got some good traction started..

The Air Force did convince the powers that be that it needed the Titan III-C, which was in the same class as the Saturn I (though somewhat smaller than the Saturn IB, or course).  I think there could have been an opportunity there to have a Saturn I-class booster used by both the Air Force and NASA.  As it was, there were some fierce arguments between the Titan III-C and Saturn camps.  There's an interesting Titan III history that's been posted somewhere on this site (by Blackstar?).  The Air Force was claiming at one point, for example, that the Saturn's 8-engine cluster was so complex that it wasn't clear it would ever work, let alone be reliable.

Yea, I think a bit of a problem there, is the USAF wanted a system based on their Titan ICBM, which needed storable propellants, as it would be sitting around in missile silos for years.  So hypergolics or solids were the obvious choices there.
NASA doesnít need rockets that use storable propellants, they can fuel it up prior to liftoff just fine.  So I could see NASA wanting to go with higher performance non-storable cyrogenics like kerolox and hydrolox.  Titanís hypergolic core was obviously not a really efficient propellant, and very toxic. 
USAF could certainly use a cryogenic rocket like NASA for their satellite missions, because the criteria is the same as for NASA.  But (I am assuming here), since they already had the Titan II ICBM, by adding some SRBís to it, they could get the payload capacity they needed, without the need for another separate rocket system to maintain.  And that makes sense really. 
The problem for NASA is that it would be pretty difficult to do a lunar mission with just Titan IIIC launches.  It would require a bunch of in orbit assembly and elements that had never been done, and werenít sure could be done in space until Gemini showed they could.  But even then, Iím sure they wanted to keep the number of in orbit assembly and docking maneuvers down to a bare minimum to reduce the LOM or LOC chances for a lunar mission, which would already be full of LOM or LOC risks.

It just would have been nice if the two could have come together on some things.  Like a smaller MLV which used USAFís existing SRBís.  USAF gets itís Titan III, and NASA gets a crogenic high performance rocket that could do a lunar mission in two or perhaps even one launch.

Offline RocketmanUS

  • Senior Member
  • *****
  • Posts: 2226
  • USA
  • Liked: 71
  • Likes Given: 31
No better but different.
Titan IIIC and or Saturn 1B.
Space station launch by either with add on modules.
Assemble cargo or crew Lunar vehicle at station.

Station for space research or space assemble during the year for what space program was needed at the time. A lot smaller than ISS, but modules about the same size. Use modifies Apollo CSM for a short duration module, use for experimenting on new equipment and or things that they wanted to return to Earth after they were done with it at the station.

This could have given them the flexibility to do Lunar missions when they wanted to without a bigger commitment. Use hypergolic fueled EDS, easy to store in space till needed. Crew could have launched to station weeks before their intended launch window, no launch or weather delays this way. With these launchers Apollo CM would have had to add propellent to it's tanks at the station for a Lunar mission.

As far as a better Saturn V/Lunar Program have looked like, I think Saturn V would have needed to be replace by INT-20/21 and use a dedicated assemble station for BLEO missions and launch the LH2/LOX EDS last with crew already at the station for crewed missions.

We could have had the Apollo CSM in place for either time of mission even if they made a LEO version of the Apollo CSM, people and factory would still be there.

Offline go4mars

  • Senior Member
  • *****
  • Posts: 3752
  • Earth
  • Liked: 152
  • Likes Given: 3153
Sea Dragon. -Bob Truax
Elasmotherium; hurlyburly Doggerlandic Jentilak steeds insouciantly gallop in viridescent taiga, eluding deluginal Burckle's abyssal excavation.

Offline Lars_J

  • Senior Member
  • *****
  • Posts: 6161
  • California
  • Liked: 665
  • Likes Given: 195
However, if you are going to the moon, then you need an EDS.  A multi-core first stage using a gas generator (low ISP) engine would be limited once it got past the lower ascent, wouldnít it?  Could an S-IVB stage make up the difference, and then also to the TLI burn?  In Saturn, the S-II did most of that upper ascent.  The S-IVB didnít have to do a whole lot in addition.  Wouldnít a multi-core first stage kerolox GG only be useful to about the altitude the S-IC was?  And if you need two more stages on top like the S-IC did, then what have you gained?  Other than a bit more scalable system.

Thatís why I thought of the two hydrolox stages both based off the S-IV stage.  ...

While hydrolox makes a lot of sense for an EDS, I'm not sure I understand your "hydrolox focus". Sure, it matches NASA who at the time (and since then) has had a "hydrolox or bust" mentality. BUT... If you are really interested in a more affordable Apollo/Saturn-style program, it would probably be a good idea to take a second look at "kerolox". It still works over 100km altitude you know. ;) Hydrolox is great, but you have to balance the added performance with the added cost & complexity.

I'm not against hydrolox, but it there was one element I would not want to lose in a "better lunar program", it would be the F-1 engine.

Offline RocketmanUS

  • Senior Member
  • *****
  • Posts: 2226
  • USA
  • Liked: 71
  • Likes Given: 31
However, if you are going to the moon, then you need an EDS.  A multi-core first stage using a gas generator (low ISP) engine would be limited once it got past the lower ascent, wouldn’t it?  Could an S-IVB stage make up the difference, and then also to the TLI burn?  In Saturn, the S-II did most of that upper ascent.  The S-IVB didn’t have to do a whole lot in addition.  Wouldn’t a multi-core first stage kerolox GG only be useful to about the altitude the S-IC was?  And if you need two more stages on top like the S-IC did, then what have you gained?  Other than a bit more scalable system.

That’s why I thought of the two hydrolox stages both based off the S-IV stage.  ...

While hydrolox makes a lot of sense for an EDS, I'm not sure I understand your "hydrolox focus". Sure, it matches NASA who at the time (and since then) has had a "hydrolox or bust" mentality. BUT... If you are really interested in a more affordable Apollo/Saturn-style program, it would probably be a good idea to take a second look at "kerolox". It still works over 100km altitude you know. ;) Hydrolox is great, but you have to balance the added performance with the added cost & complexity.

I'm not against hydrolox, but it there was one element I would not want to lose in a "better lunar program", it would be the F-1 engine.
If we replaced the Saturn 3rd stage for the TLI burn for the Apollo CSM/LEM with a RP-1/LOX stage what would the mass before the TLI burn of this stage be ( dry mass, propellant mass )?

How much cheaper would such a stage be ( 10% , 20 % cheaper )?
« Last Edit: 10/17/2012 10:08 PM by RocketmanUS »

Offline Archibald

  • Senior Member
  • *****
  • Posts: 2595
  • Liked: 471
  • Likes Given: 1096
Here's my take at a better Apollo (version 2.0)
http://forum.nasaspaceflight.com/index.php?topic=26667.msg957036#msg957036
Incidentally, Saturn C2 (no solids) payload to orbit was quite similar to the shuttle, a good 22 tons to Earth orbit. At worse, Saturn C2 becomes an American Proton and is paid through launches of GEO comsats.

When I wrote this scenario I picked Saturn C2 over the bigger sisters because (with perfect hindsight) I knew of Proton and Ariane 5, of ILS and Arianespace.
22 tons is the upper level the scientists, commercial market and military can afford.
The basic Saturn C2 could either boost a 6-ton comsat to GEO; boost the Voyager probes to Jupiter, or Viking to Mars; and launch a KH-9 into polar orbit. It wouldn't be a rocket for manned spaceflight alone, as were the bigger C3, C4, C5 and C8.

...you have been found guilty by the elders of the forum of a (imaginary) vendetta against Saint Elon - BLAAASPHEMER !

Offline Proponent

  • Senior Member
  • *****
  • Posts: 5587
  • Liked: 1135
  • Likes Given: 682
Here's my take at a better Apollo (version 2.0)
http://forum.nasaspaceflight.com/index.php?topic=26667.msg957036#msg957036
Incidentally, Saturn C2 (no solids) payload to orbit was quite similar to the shuttle, a good 22 tons to Earth orbit. At worse, Saturn C2 becomes an American Proton and is paid through launches of GEO comsats.

When I wrote this scenario I picked Saturn C2 over the bigger sisters because (with perfect hindsight) I knew of Proton and Ariane 5, of ILS and Arianespace.
22 tons is the upper level the scientists, commercial market and military can afford.
The basic Saturn C2 could either boost a 6-ton comsat to GEO; boost the Voyager probes to Jupiter, or Viking to Mars; and launch a KH-9 into polar orbit. It wouldn't be a rocket for manned spaceflight alone, as were the bigger C3, C4, C5 and C8.

That's kinda what I think, at least if we're talking just about single-core rockets.  Something the size of the Saturn C-2 is probably about as large as you could go and still expect it to have non-HSF uses, which would be essential to keep costs down.

Note that the Saturn IB had nearly double the payload of the Saturn I (C-1).  I imagine that the C-2 would have ended up being somewhat more capable than the numbers from 1961 indicate.

Offline RanulfC

  • Senior Member
  • *****
  • Posts: 4445
  • Heus tu Omnis! Vigilate Hoc!
  • Liked: 806
  • Likes Given: 32
Now if they [USAF] could somehow "convince" the "powers-that-be" and THEY needed a Saturn-1 class booster you've got some good traction started..

The Air Force did convince the powers that be that it needed the Titan III-C, which was in the same class as the Saturn I (though somewhat smaller than the Saturn IB, or course).  I think there could have been an opportunity there to have a Saturn I-class booster used by both the Air Force and NASA.  As it was, there were some fierce arguments between the Titan III-C and Saturn camps.  There's an interesting Titan III history that's been posted somewhere on this site (by Blackstar?).  The Air Force was claiming at one point, for example, that the Saturn's 8-engine cluster was so complex that it wasn't clear it would ever work, let alone be reliable.

Yea, I think a bit of a problem there, is the USAF wanted a system based on their Titan ICBM, which needed storable propellants, as it would be sitting around in missile silos for years.  So hypergolics or solids were the obvious choices there.
NASA doesnít need rockets that use storable propellants, they can fuel it up prior to liftoff just fine.  So I could see NASA wanting to go with higher performance non-storable cyrogenics like kerolox and hydrolox.  Titanís hypergolic core was obviously not a really efficient propellant, and very toxic.
Lest we forget though the Titan-1 was a LOX/Kero powered missile :)

But yes, it basically came down to different "needs" both operational and technical. (A LOT of my "point" there was that had the DoD/AF ever managed to come up with a "viable" reason for MANNED space launch capabilty it would have gone a long way towards merging their "needs" with those of NASA)

I like this one :)
No better but different.
Titan IIIC and or Saturn 1B.
Space station launch by either with add on modules.
Assemble cargo or crew Lunar vehicle at station.

Station for space research or space assemble during the year for what space program was needed at the time. A lot smaller than ISS, but modules about the same size. Use modifies Apollo CSM for a short duration module, use for experimenting on new equipment and or things that they wanted to return to Earth after they were done with it at the station.

This could have given them the flexibility to do Lunar missions when they wanted to without a bigger commitment. Use hypergolic fueled EDS, easy to store in space till needed. Crew could have launched to station weeks before their intended launch window, no launch or weather delays this way. With these launchers Apollo CM would have had to add propellent to it's tanks at the station for a Lunar mission.

Which of course is the way is was "supposed" to happen, or so everyone thought :)

On the other hand, I believe that Archibald and Proponent have a very good point on the Saturn C-2 (or 1b type) first stage being about the "right" size for most missions. Making it capable of using Titan class solids would have worked out well for the AF, though it would have "competed" directly with the heavier Titan versions in the end the cost savings of having both NASA and DoD/AF uses as well as for heavier commercial payloads would have been a significant factor.

Randy
From The Amazing Catstronaut on the Black Arrow LV:
British physics, old chap. It's undignified to belch flames and effluvia all over the pad, what. A true gentlemen's orbital conveyance lifts itself into the air unostentatiously, with the minimum of spectacle and a modicum of grace. Not like our American cousins' launch vehicles, eh?

Offline Lobo

  • Senior Member
  • *****
  • Posts: 6758
  • Spokane, WA
  • Liked: 555
  • Likes Given: 348

While hydrolox makes a lot of sense for an EDS, I'm not sure I understand your "hydrolox focus". Sure, it matches NASA who at the time (and since then) has had a "hydrolox or bust" mentality. BUT... If you are really interested in a more affordable Apollo/Saturn-style program, it would probably be a good idea to take a second look at "kerolox". It still works over 100km altitude you know. ;) Hydrolox is great, but you have to balance the added performance with the added cost & complexity.

I'm not against hydrolox, but it there was one element I would not want to lose in a "better lunar program", it would be the F-1 engine.

Itís not really a hydrolox focus.  I think kerolox makes a much better first stage booster.  Iím not even a big fan of solids.
However, a lunar program definitely needs a large hydrolox EDS.  Thatís a given.  So such a stage needs developed no matter what.  That means hydrolox engines need to be developed, hydrolox tanks and insulation.  Hydrolox infrastructure and handling.  And while not required, common bulkhead technology Ėwas- developed for S-IVB and S-II. 
So that all had to be developed no matter what.  The only variable would be if J2 wasnít needed, then RL-10ís could be used.  The original S-IV had six RL-10ís, but as I understand, the S-IVB was bigger, and needed to do enough of the ascent that six RL-10ís didnít have enough thrust?  So they went with J2 on the S-IVB rather than the RL-10ís.  (If that is incorrect, someone feel free to correct me.  :-) )

I donít think kerolox 1st stage boosters really get high or fast enough on a heavy lift vehicle where RL-10ís could practically be used, or at least there would need to be so many of them they wouldnít fit.  So one way or the other, if you are talking kerolox 1st stage on a large rocket, you need something more powerful than RL-10, like the J2. 

So, Iím just saying, the J2 will be needed anyway, as well as a hydrolox large stage development and production.  But by using existing Titan SRBís, the whole kerolox engine and stage development can be eliminated.  NASA doesnít have to pay for itís development (which isnít the real problem, they had oodles of money flowing in at that time), and NASA doesnít have to pay for the overhead of that production line (which Ėis- a big concern post Apollo).  USAF paid for the development of the Titan SRBís, and was paying to maintain their production for several decades.

The Saturn C2 has H-1 engines, J2 engines, and RL-10 engines (on the S-IV stage).  That is 3 different stages, with 3 different engines.  If you went with F-1 on the first stage, you are in the same boat.  It has four stages and 3 engines.  Although USAF starting using Centaur and RL-10 on Atlas so NASA wouldnít have to maintain those lines by themselves. 
And  the 6.6m ďS-IIĒ and the 6.6m S-IV could be both made on the same production line, like in my concept with the core and upper stage.
So what about the Saturn C2, but replace the S-I stage with Titan SRBís strapped on to the 6.6m S-II stage?  And air-ignite the J2 engines on the S-II stage at the end of the SRB burn, as was done for Titan-IIIC.  Youíd probably only need two Titan SRBís to replace the capacity of the S-I stage.  But if you put four on there, it would increase the capacity.

That would basically be like my concept, but my core would probably be wider than the 6.6m S-II, and designed for heavier lift capability with up to 8 SRBís.  But it could still launch with just two Titan boosters for Smaller payloads.  The upper stage would be whatever width the core is for commonality in the production line.
And hereís another advantage of a hydrolox core, if you are just going to LEO, you donít need the upper stage.  You can launch LEO payloads (like Apollo CSM to a space station) with just the core some SRBís.  The core with two SRBís would probably be all thatís needed to get a partially fueled Apollo CSM to a space station, with similar (or better) capacity than the Saturn 1B.  So you donít need to expend that expensive EDS/upper stage for LEO missions, the way Saturn 1B needed to expend a S-IVB every launch. 

Anyway, thatís my reasoning for dropping kerolox all together.  Just to reduce the number of stages and engines needing development and overhead, as NASA would be the only user of them.  Titan SRBís existed, and could replace the kerolox booster.  Not because itís better, but because itís cheaper and they existed.

Titan SRBís just seem like a good resource that could have been used by NASA.  Imagine how much development cost and time could have been saved by NASA on STS if theyíd used four Titan SRBís instead of the two Shuttle SRBís? (two UA1207 boosters approximate one shuttle booster pretty well actually)  And then they could have developed reusable kerolox boosters later, and developed them over time so all of that development wouldnít have to be done up front, if they wanted to.
In fact, imagine how much more development cost if an S-II stage had been used instead of the new 8.4m ET, and J2S instead of the newly developed RS-25?  And then the Shuttle would be launched on top rather than side mount, as the S-II stage was already support that mass.  Then you would have had basically my concept or the Saturn II concept available to NASA has a stand alone LV that could launch cargo payloads. And there wouldnít have been the chance of debris strikes to the Shuttle head shield during ascent.  If reusable liquid boosters were developed later, then they could have replaced the Titan SRBís on the S-II core. 
The S-II core would probably either need to be stretched, or perhaps six Titan boosters could be used and the J2Sís air-ignited.  The Shuttle would be on top so there wouldnít be any goofy side loads.

Offline Archibald

  • Senior Member
  • *****
  • Posts: 2595
  • Liked: 471
  • Likes Given: 1096
Quote
ery good point on the Saturn C-2 (or 1b type) first stage being about the "right" size for most missions. Making it capable of using Titan class solids would have worked out well

And of course by dropping Titan SRMs into the ocean under parachutes they could have tried their hand at reusability (although we all know, with perfect shuttle hindsight, how that business ended).

Quote
So what about the Saturn C2, but replace the S-I stage with Titan SRBís strapped on to the 6.6m S-II stage?

I see your point. You want to get ride of that clunky S-IB. 
Fair enough, sure the S-IB stage was far from perfect - I tend to see it as a heavy and expensive kludge of Jupiter tanks and engines.
I hope you realize that a  launcher made of two Titan 5-seg SRMs + a J-2 core + a Centaur or Transtage ontop of that would essentially end as an American Ariane 5... or H2;D
The funny side of writting alternate history, I would say.

Quote
Titan SRBís just seem like a good resource that could have been used by NASA.  Imagine how much development cost and time could have been saved by NASA on STS if theyíd used four Titan SRBís instead of the two Shuttle SRBís? (two UA1207 boosters approximate one shuttle booster pretty well actually)

(Snip)

In fact, imagine how much more development cost if an S-II stage had been used instead of the new 8.4m ET, and J2S instead of the newly developed RS-25?

At time NASA suffers from lunacies that are hard to understand.
Lunacy number 1 "hydrolox or bust"
Lunacy number 2 "not invented here" (they are not the only ones, admittedly)
Lunacy number 3 "never, never reuse what exists. Better to re-invent things at great public expense."
Martin Marietta actually had a Shuttle concept featuring 4*SRMs late 1971.
But 4*7-seg = 12 field joints / O-rings.
 Challenger only had six O-rings, one failed, and it blew. IMHO. Twice more risk.

The hybrid Apollo / Shuttle you describes was, at some point (september / october 1971) Fletcher trick to try and convince Nixon Bureau of Budget to give them the money.
Fletcher imagined a Mark 1 shuttle with an ablative heatshield and three or four J-2s. Ceramic tiles and SSMEs were to be introduced on a later Mark II. The trick proved unnecessary in the end.
« Last Edit: 10/19/2012 03:22 PM by Archibald »
...you have been found guilty by the elders of the forum of a (imaginary) vendetta against Saint Elon - BLAAASPHEMER !

Offline edkyle99

  • Expert
  • Senior Member
  • *****
  • Posts: 12946
    • Space Launch Report
  • Liked: 4004
  • Likes Given: 763
So in short, how could we have gotten to the Moon by December of 1969 in a cheaper and more sustainable way, that could have then carried on past Apollo 17, eliminating any HSF gap, and then dovetailing into a 70ís and 80ís new focus for NASA which was basically LEO space stations? 

Given the restrictions you've imposed in this question, I think that the answer is Saturn V and Lunar Orbit Rendezvous.  The principal restriction that forces this answer is the need to get to the Moon before 1970.  Saturn V and Apollo were the answer then to JFK's artificial deadline (which was really a challenge to beat the USSR).   

Remember that it was the realities of that deadline that forced von Braun, finally, to agree that LOR using Saturn V was the way to go though he had argued long and hard for EOR.

If you drop the timeline restriction, the possibilities open up.  EOR using smaller rockets (but still bigger than Titan IIIC) becomes possible.  Spreading out the cost over a longer time frame to meet smaller budgets (i.e., a slower mission pace) becomes possible.  Etc.

 - Ed Kyle

Offline Lobo

  • Senior Member
  • *****
  • Posts: 6758
  • Spokane, WA
  • Liked: 555
  • Likes Given: 348

And of course by dropping Titan SRMs into the ocean under parachutes they could have tried their hand at reusability (although we all know, with perfect shuttle hindsight, how that business ended).


Yea, Iíd think it wouldnít have been a problem for NASA to add recoverability to the boosters, but that could have been a block upgradeÖand maybe never actually added.  As long as it was part of the ďplanĒ for a partially reusable system.  And if they did do it, they would have been starting with off-the-shelf production SRBís, rather than brand new beasts.  Hopefully a sort of ďrecovery kitĒ could have been added to the standard Titan Booster at KSC to make them recoverable.  Although, the big question would be if the casings themselves could be refurbished and refueled by Martin, or if one use basically ruins the casing so it canít be safely reused.  If there was an issue with that, then probably the better way would have been to use them in the ďBlock 1Ē STS, and then have a block upgrade that replaces them with reusable liquid boosters at some point down the road.  Probably fly-back boosters using a new F-1A or something.  That may or may not actually have ever happened, but that could have been the PoR official path towards reusability.  Some studies could have been done, like was done to replace the actual STS SRBís, and probably they just would have rolled with the Titan boosters for the duration of STS. 
If the Titan booster casings Ėcould-be reused, and it was just a matter of recovering them, that would have been a reasonable block upgrade then.


I see your point. You want to get ride of that clunky S-IB. 
Fair enough, sure the S-IB stage was far from perfect - I tend to see it as a heavy and expensive kludge of Jupiter tanks and engines.
I hope you realize that a  launcher made of two Titan 5-seg SRMs + a J-2 core + a Centaur or Transtage ontop of that would essentially end as an American Ariane 5... or H2;D
The funny side of writting alternate history, I would say.


And nothing really against the S-1B stage.  But with hindsight, we could have skipped itís development entirely.  Even though it used existing tanks, it was still a brand new stage, with a brand new kerolox engine, with X amount of development cost and time, and Y amount of overhead to maintain the engine and stage production lines.  That could be done away with by using SRBís the USAF paid to develop.  Just saying use what was there basically.  Additionally we could have skipped the S-IC development and overhead, as well as that for the F-1, in my alternative concept.  That saves more development and overhead money for the same reason skipping the S-1B does.

At time NASA suffers from lunacies that are hard to understand.
Lunacy number 1 "hydrolox or bust"
Lunacy number 2 "not invented here" (they are not the only ones, admittedly)
Lunacy number 3 "never, never reuse what exists. Better to re-invent things at great public expense."
Martin Marietta actually had a Shuttle concept featuring 4*SRMs late 1971.
But 4*7-seg = 12 field joints / O-rings.
 Challenger only had six O-rings, one failed, and it blew. IMHO. Twice more risk.

The hybrid Apollo / Shuttle you describes was, at some point (september / october 1971) Fletcher trick to try and convince Nixon Bureau of Budget to give them the money.
Fletcher imagined a Mark 1 shuttle with an ablative heatshield and three or four J-2s. Ceramic tiles and SSMEs were to be introduced on a later Mark II. The trick proved unnecessary in the end.

Yea.  Iíve seen some of those alternate STS concepts.  One But a four SRB on Titan core (Titan IIIM I think it was called) and the Oribiter on top with side mount drop tanks, as it would do itís own upper ascent.  Another concept used the S-IC stage as a booster, and the S-II stage as the ET, with five J2Sís on the Orbiter in a side mount configuration.  These gave me the idea for my concept.  In the real history, I think mounting the Titan SRBís to the S-II stage would have been a good compromise.  Then NASA is only maintain the S-II line and J2S engine itself, and saves all of that development.  USAF maintains the Titan SRB line, NASA just buys them as needed. 

Then the focus in the 70ís could have been all on the reusable orbiter itself, with very little needing done on the booster.  Itíd just be existing S-II stage modified to accept 2-8 Titan boosters, with the upgraded, cheaper and simplified J2S engine (which PWR basically had already developed), and off-the shelf Titan boosters.  I would think the Saturn V Avionics ring used in the S-IVB could be used for the booster when launching without the orbiter as a cargo launcher.  That was the plan for INT-21 anyway.  The stack that launched Skylab kept the ring on the S-IVB stage that was converted to Skylab I believe.  The reusable orbiter would have the avionics package when it was being launched, just as it was for actual STS.  The ML/MLP that launched the stack could be used for either the stand along LV or the stack with orbiter.  I suppose a problem is that four Titan boosters is about the same mass as two Shuttle SRBís (a bit more actually).  The pads would probably have needed the fixed towers they got anyway for STS.  But that means four Titan SRBís would be the max number the CT could carry with the stack.  Iíd like to see this LV used 2-8 SRBís for various lift configurations.  I wonder if thereís any chance they could be added at the pad?  The S-II stage could support the weight of the orbiter at the pad, just as it supported the dry weight of the S-IVB and fueled weight of the LEM and Apollo CSM.  The SRBís wouldnít bee needed to carry the weight as they did in STS.  So maybe they could be added at the pad?  That would allow up to 8 added at the pad, and the tower to be attacked to the ML. 
And really, This configuration could have changed the design of the orbiter a lot.  It would have been more of just a crew carrier and light cargo hauler (supplies to a space station and the like), rather that needing to carry medium class payload of the size of the cargo bay.  Payloads that large could be launched by the cargo version.   The Orbiter cold be much smaller, with maybe 10mt of cargo capacity.  Enough for things like Satellite repair and space station resupply. 

The USAF could have used this cargo launch with an upper stage for any payloads that needed more than Titan IIIís capability.  Titan IV would never bee needed (this would sort of be like a ďTitan VĒ LVÖTitan boosters with a Saturn V stage, more powerful than Titan IV would beÖhence ďTitan VĒ).
And the USAF could have actually retired the Titan II core (at least for production of new ones), and flew all their payloads on ďTitan VĒ.  They could have cost shared with NASA on both the SRBís and S-II, as well as an upper stage.  S-IVB could have been kept from Saturn for an upper stage, but until NASA was planning on going heavy lift BLEO, probably just the S-II core with two Titan boosters and a Centaur upper stage would have been good enough for the payloads launched on Titan III or Titan IV. 
So if Reagan had mandated that NASA and USAF both use just one common launcher, as he did with STS, a Challenger-like event wouldnít have grounded the Titan V cargo launcher like it did STS.  Titan V could launch without the orbiter, so there wouldnít be the human risk involved with trying to launch again like there was post-Challenger. (of course, I donít think the Titan boosters are segmented, so I donít think what happened to Challenger Ėcould- happen to this LV?  And since the orbiter is on top of the stack, what happened to Columbia wouldnít have happened to this either.  But the point is a LOC event wouldnít need to ground the unmanned version while NASA was figuring out how to make it safe for a crew again.) 
So that could have really reduced the costs of STS in terms of both overhead and production/hardware costs for NASA, as well as reducing the risk to the orbiter from debris strikes, and also given NASA a medium-heavy launcher for large payloads like space station segments. 

Sounds pretty coolÖbut I digressÖ.   :-)

Offline Proponent

  • Senior Member
  • *****
  • Posts: 5587
  • Liked: 1135
  • Likes Given: 682
The Saturn C2 has H-1 engines, J2 engines, and RL-10 engines (on the S-IV stage).  That is 3 different stages, with 3 different engines.  If you went with F-1 on the first stage, you are in the same boat.  It has four stages and 3 engines.  Although USAF starting using Centaur and RL-10 on Atlas so NASA wouldnít have to maintain those lines by themselves.

The H-1 was essentially the same engine used on the Delta, so the only unique engine is the J-2.

Quote
And  the 6.6m ďS-IIĒ and the 6.6m S-IV could be both made on the same production line, like in my concept with the core and upper stage.
So what about the Saturn C2, but replace the S-I stage with Titan SRBís strapped on to the 6.6m S-II stage?  And air-ignite the J2 engines on the S-II stage at the end of the SRB burn, as was done for Titan-IIIC.  Youíd probably only need two Titan SRBís to replace the capacity of the S-I stage.  But if you put four on there, it would increase the capacity.

That would basically be like my concept, but my core would probably be wider than the 6.6m S-II, and designed for heavier lift capability with up to 8 SRBís.  But it could still launch with just two Titan boosters for Smaller payloads.  The upper stage would be whatever width the core is for commonality in the production line.
And hereís another advantage of a hydrolox core, if you are just going to LEO, you donít need the upper stage.  You can launch LEO payloads (like Apollo CSM to a space station) with just the core some SRBís.  The core with two SRBís would probably be all thatís needed to get a partially fueled Apollo CSM to a space station, with similar (or better) capacity than the Saturn 1B.  So you donít need to expend that expensive EDS/upper stage for LEO missions, the way Saturn 1B needed to expend a S-IVB every launch.

Two concerns come to mind.  One, I suspect there would be a reliability problem with a many-SRB vehicle.  In another thread, we've been debating the reliability of multi-engine first stages with varying levels of engine-out tolerance.  With SRBs, there is no engine-out tolerance -- each of them must work.  The other point is, if we're going to have sustainability, presumably the Air Force and NASA are both using this vehicle.  In that case, if something like a C-2 were in use (or a C-1, if you take out one stage), then there's no need for the Titan III-C, and hence no need for Titan-like SRBs.

Offline RocketmanUS

  • Senior Member
  • *****
  • Posts: 2226
  • USA
  • Liked: 71
  • Likes Given: 31
Quote
ery good point on the Saturn C-2 (or 1b type) first stage being about the "right" size for most missions. Making it capable of using Titan class solids would have worked out well

And of course by dropping Titan SRMs into the ocean under parachutes they could have tried their hand at reusability (although we all know, with perfect shuttle hindsight, how that business ended).
They could have just retrieve the SRB's to study how they might be able to reuse them economically. Might have been able to learn how to retrieve a liquid booster.

Offline MikeAtkinson

  • Full Member
  • ****
  • Posts: 1812
  • Bracknell, England
  • Liked: 576
  • Likes Given: 74
Saturn V replacement

A 6.6m 3 core 1st stage, boosters have 2 F-1, middle core a single F-1. Boosters burn for about 125 s and are then released. Middle core burns for another 125 s. Second stage similar to S-II but 6.6m and hence longer. Third stage exactly the same as the S-IVB. Apollo moon mission unchanged.


20+ tonne to LEO (Saturn 1b replacement)

Light version: just the middle core (with some propellant offload) + S-IVB .


40 tonne to LEO

Intermediate version: booster + S-IVB (one F1 shut down early to limit G loads)


Although these would not reduce development cost, production could have continued for the light or intermediate versions at a fraction of the cost of the full Apollo moon program.

Offline Proponent

  • Senior Member
  • *****
  • Posts: 5587
  • Liked: 1135
  • Likes Given: 682
If we replaced the Saturn 3rd stage for the TLI burn for the Apollo CSM/LEM with a RP-1/LOX stage what would the mass before the TLI burn of this stage be ( dry mass, propellant mass )?

How much cheaper would such a stage be ( 10% , 20 % cheaper )?

In round figures, a dedicated lox/RP-1 TLI stage would weigh about 250,000 lb as opposed to a dedicated lox/hydrogen stage, which would be about 150,000 lb (the actual S-IVB was heavier, because about a third of its propellant was expended during ascent to orbit).  That's about two more launches of the Saturn C-2 or equivalent.  This assumes the non-engine dry weight of the RP-1 stage would be 5% of the propellant mass, while that of the hydrogen stage would be 9%.

The RP-1 stage itself, excluding propellant, might be a little lighter and perhaps a bit cheaper.

The case for using hydrogen in the TLI stage looks pretty compelling to me.  If it's to difficult to develop the technology for transferring liquid hydrogen in orbit, the TLI stage could be launched full of hydrogen, with only the oxygen being stored in orbit.
« Last Edit: 10/20/2012 01:23 PM by Proponent »

Offline RyanC

  • Full Member
  • ****
  • Posts: 402
  • SA-506 Launch
  • Liked: 51
  • Likes Given: 9
INT-20 and INT-21 made for some interesting concepts, but they still werenít great ways to scale down.  INT-21 actually was pretty good for a fairly heavy LEO launcher.  INT-20 had a much too powerful first stage for itís S-IVB upper stage.

That's why you delete F-1s from the S-ID or J-2s from the S-IIB as needed by the mission; to balance cost/needs against what that mission needs -- you save money by using the same production line for stages for everything from medium lift to heavy lift -- it's only aluminum and aluminum is cheap.

Offline spectre9

  • Senior Member
  • *****
  • Posts: 2403
  • Australia
  • Liked: 36
  • Likes Given: 67
Should've built the Saturn C-8  :D

HLLVs are too expensive these days. Surely it wouldn't have cost too much extra back then.

Direct ascent was a silly bloated mission but I think it would've enabled all sorts of wondrous adventures and possibly even landing at a Lunar pole and Mars before the year 2000.

Offline Archibald

  • Senior Member
  • *****
  • Posts: 2595
  • Liked: 471
  • Likes Given: 1096
Quote
The case for using hydrogen in the TLI stage looks pretty compelling to me.  If it's to difficult to develop the technology for transferring liquid hydrogen in orbit, the TLI stage could be launched full of hydrogen, with only the oxygen being stored in orbit.

Indeed. In fact the LEO > Earth escape segment (3.1 km/s delta-V) was the big roadblock, and still is. For all the studies done of SEP or NTR, today we are still expending large LOX/LH2 chemical stages there.
As for LH2, damn the boiloff, but fortunately on a 120 tons S-IVB it represents a mere 15-20 tons. Everything else is either the stage empty mass and of course liquid oxygen. So a single Saturn IB could haul the LH2 tank.
The logical order seem to be
- first launch: large LOX tank, empty
- next launches: 5 or 6 LOX tankers to fill it
- then : the payload (CSM, LM, and on)
- followed by the crew
- and lastly (because it boils) the LH2 tank.
...you have been found guilty by the elders of the forum of a (imaginary) vendetta against Saint Elon - BLAAASPHEMER !

Offline Proponent

  • Senior Member
  • *****
  • Posts: 5587
  • Liked: 1135
  • Likes Given: 682
Should've built the Saturn C-8  :D

HLLVs are too expensive these days. Surely it wouldn't have cost too much extra back then.

Direct ascent was a silly bloated mission but I think it would've enabled all sorts of wondrous adventures and possibly even landing at a Lunar pole and Mars before the year 2000.

All of those things could have been done with the Saturn V too, but the US government wasn't interested in funding it, and having the C-8 wouldn't have changed that.

Offline spectre9

  • Senior Member
  • *****
  • Posts: 2403
  • Australia
  • Liked: 36
  • Likes Given: 67
They would've needed to build a new plant as MAF couldn't build something that big.

That plant might have been built in a better area to receive big funding.

We'll never know.

Offline RanulfC

  • Senior Member
  • *****
  • Posts: 4445
  • Heus tu Omnis! Vigilate Hoc!
  • Liked: 806
  • Likes Given: 32
Quote
very good point on the Saturn C-2 (or 1b type) first stage being about the "right" size for most missions. Making it capable of using Titan class solids would have worked out well

And of course by dropping Titan SRMs into the ocean under parachutes they could have tried their hand at reusability (although we all know, with perfect shuttle hindsight, how that business ended).

Lest we "hind-sight" to much though it's a good idea to keep in mind that the Titan SRMs would have been the "right-size" for a refurbishment/re-build plant AT Kennedy/Canaveral so that would have cut out the huge shipping costs of the Shuttle SRBs right there :)
(Of course that would have then made Florida 'opposed' to the development of Liquid replacement boosters instead of Utah... :) )

Quote
At time NASA suffers from lunacies that are hard to understand.
Lunacy number 1 "hydrolox or bust"
Lunacy number 2 "not invented here" (they are not the only ones, admittedly)
Lunacy number 3 "never, never reuse what exists. Better to re-invent things at great public expense."
Also the whole "reusable-costs-less-no-matter-the-flight-rate" (or budget) thing and once they developed LH2/LOX engines "SSTO-was-just-around-the-corner" was prevelent too.

A HUGE amount of "it" seemed to be centered around the "math" all looking so great, but the actual engineering and details getting in the way more than anything else.

So in short, how could we have gotten to the Moon by December of 1969 in a cheaper and more sustainable way, that could have then carried on past Apollo 17, eliminating any HSF gap, and then dovetailing into a 70ís and 80ís new focus for NASA which was basically LEO space stations? 

Given the restrictions you've imposed in this question, I think that the answer is Saturn V and Lunar Orbit Rendezvous.  The principal restriction that forces this answer is the need to get to the Moon before 1970.  Saturn V and Apollo were the answer then to JFK's artificial deadline (which was really a challenge to beat the USSR).   

Remember that it was the realities of that deadline that forced von Braun, finally, to agree that LOR using Saturn V was the way to go though he had argued long and hard for EOR.

Good thing to keep in mind! The whole "time" issue is what drove Apollo since we had pretty much NO space experiance when Kennedy laid down the deadline, we had to take an awful lot of short-cuts to get to the Moon.

Quote
If you drop the timeline restriction, the possibilities open up.  EOR using smaller rockets (but still bigger than Titan IIIC) becomes possible.  Spreading out the cost over a longer time frame to meet smaller budgets (i.e., a slower mission pace) becomes possible.  Etc.
The "problem" though is without the "deadline" how likely is it that Congress would have signed off on the needed budget? Worse from a "political" perspective alone we were already WAY behind and had the Soviets not had the internal issues (and technical issues) they had more "time" might have given them both the ability and incentive to make it a "real" race to the Moon.

Good/Bad? Hard to tell, though it probably would have made the whole program a lot more "sustainable" over the long run. (Something I fear we STILL need to learn)

Randy
From The Amazing Catstronaut on the Black Arrow LV:
British physics, old chap. It's undignified to belch flames and effluvia all over the pad, what. A true gentlemen's orbital conveyance lifts itself into the air unostentatiously, with the minimum of spectacle and a modicum of grace. Not like our American cousins' launch vehicles, eh?

Offline Downix

  • Senior Member
  • *****
  • Posts: 7087
  • Liked: 16
  • Likes Given: 1
I would have used an earlier version of the Saturn C-3, 6.6m diameter core. Instead of an in-line stage, used two C-3 "first stages" as boosters to the C-3 "second stage" and an S-IVB upper stage. By parallel burning instead of serial, the 4-engined 6.6m S-II with two S-IB-C-3 6.6m as boosters, could have rivalled the Saturn V for performance. This configuration would have also been more affordable to operate, being scalable to meet the solution needed.
chuck - Toilet paper has no real value? Try living with 5 other adults for 6 months in a can with no toilet paper. Man oh man. Toilet paper would be worth it's weight in gold!

Offline Lobo

  • Senior Member
  • *****
  • Posts: 6758
  • Spokane, WA
  • Liked: 555
  • Likes Given: 348
I would have used an earlier version of the Saturn C-3, 6.6m diameter core. Instead of an in-line stage, used two C-3 "first stages" as boosters to the C-3 "second stage" and an S-IVB upper stage. By parallel burning instead of serial, the 4-engined 6.6m S-II with two S-IB-C-3 6.6m as boosters, could have rivalled the Saturn V for performance. This configuration would have also been more affordable to operate, being scalable to meet the solution needed.

I'm assuming that would still need an S-IV or S-IVB developed for the EDS, correct?  Wouldn't that still require the development of three new stages and 2 new engines then?  It would be more scalable than the Saturn V, certainly.  BUt would it save any development money, or after Apollo, save any overhead costs over the Full Saturn V?
I suppose it would be cheaper to maintain, as the stages are less diameter, but if NASA is the only agency using them, would we be much better off overall?

I think if we wanted to stear clear of using the Titan III SRB's, this would be probably the next best alternative.  Especially if the core and upper stage/EDS were the same diameter, as they could share the same production line as in my concept.  I just keep getting back to the concept of the Titan SRB's saves the cost of the S-IB-C3 stage and the F-1 engines.  But I suppose there was money to spare during the 60's, so perhaps the development costs aren't such a big deal.  The production and overhead costs after Apollo are what would have potentially saved the program if they'd been clearly flexible and reasonable.
« Last Edit: 10/23/2012 12:13 AM by Lobo »

Offline truth is life

  • Full Member
  • **
  • Posts: 278
  • Liked: 7
  • Likes Given: 8
Well clearly if you are looking for a more affordable system with fewer components, then you might not get Saturn V performance, and so your lunar landing strategy might not favor LOR.

As for a TLI burn - my suggestion would be to put a shortened S-IVB as a 3rd/TLI stage for lunar missions. Same tooling and engine as S-IVB.

So with two engines (F-1 and J-2), and one tank tooling (6.6m), you could lift anything from 25t with a single stick, to 85t for heavy variants (or perhaps significantly more). Costs could be brought down by mass-production of the above elements. (BTW my performance numbers are just guesstimates, feel free to correct)

Your numbers are a little high; I've been looking at performance of a similar system for a project I have going, and it would closer to 20 t in the single stick version and ~70-80 t in the three-stick version (this last is limited by thrust/weight ratio, to some extent, although the Saturn V did cut that one awfully close). Since the single-stick is basically the Saturn IB, you'd have a real do it all rocket in the end.

Two engines (H-1 for the commonality with the little Deltas, J-2 for the upper stages), ~two or 2.5 stages (a presumably monolithic first stage and long/short S-IVBs). But the H-1 was already being developed for Saturn I, so this is really only being charged J-2 development and the stages. If you wanted to do it really cheap, use the Saturn IB first stage, too...

Hm. Now, if I were doing this for real, I'd put forth an idea using a 6.6m monolithic kerolox core (using the H-1, probably, for multi-booster commonality) with a 6.6m multi-J-2 upper stage. Additional cores--up to four, perhaps--could be lashed on to increase payload to LEO. In principle, one could also perhaps use SRBs with the idea of providing additional intermediate payloads, but the base version should be pretty close to the C-2 and the value of said intermediates is somewhat questionable. As an EDS it would use the S-IV. This would be using EOR, possibly EOR/LOR, perhaps with super-Gemini (that is, a biggish two-person capsule). I'd have to run the numbers to figure out which...

Offline Proponent

  • Senior Member
  • *****
  • Posts: 5587
  • Liked: 1135
  • Likes Given: 682
In a previous post in this thread, I mentioned that I am aware of two detailed studies circa 1960 on how to go to the moon with the smaller Saturns.  The first one was essentially the Army's Project Horizon, for which I gave a link.  Here's the other study I had in mind.  I think it's quite interesting in the context of this thread, because it was done in 1961 and considers techniques ranging from rendezvous of multiple (five, to be exact) Saturn C-3s in LEO to a direct mission with Nova.  Skip to page 671 of the PDF to see a chart of the various modes considered.

Offline spacenut

  • Senior Member
  • *****
  • Posts: 2435
  • East Alabama
  • Liked: 417
  • Likes Given: 238
Since the Saturn 1B was a cluster but had 1.5million lbs thrust as well as the F1.  I think they could have built a 20' diameter tank to match the single J1 upper stage but used an F1 engine.  This should have delivered about 20 tons to LEO.  Cluster three like the Delta IV and get over 50 tons.  Probably add another 10 tons with fuel transfer to core stage.  This also would have been scalable.  You could cluster 5 together to rival Saturn V in capacity.  The systems could have been used longer.  Maybe even upgraded the F1 to the proposed 2.2 million lbs thrust.  Assembly and docking could have built a lunar mission, or a space station.  After the F1 upgrade, the first sage(s) could be parachuted back for reuse.  The Saturn 3rd stage or 2nd on the 1B could have evolved to the plug nozzle engine for reuse also.  I think all this could have been developed cheaper and faster than the Space Shuttle.  Cheaper to operate with the same capacity. 

Offline Ravaun

  • Member
  • Posts: 1
  • West Coast, USA
  • Liked: 0
  • Likes Given: 0
The best idea (and it was studied as early as 1965) would be to use a Saturn MS-IC-1.  48.15m long with 5 F-1A's.  [2,524,984] + 169,719 kg (add 31,462.5 for reusable/recoverable config. visa via Sea Dragon concept, 1963).

Interstage mass:  6,769.1 kg

SLS Stage 2, ala Project Horizon (1961).  Adding in a Nylon/SOFI external insulation (essentially Saturn II, with simplified tooling), you arrive at [767,000] + 71,525.2 kg (reusable/recoverable config, as above).

Interstage mass:  4,950.4 kg

Saturn MS-IVB-3B (study 1967, so would have to be used on 1970+ missions)
[159,200] + 20,400 kg

Assuming 4,842 lb Instr. Unit + 118,000 lb lunar mission stage, total payload mass of:  55,720.2 kg

Performance:  800 + 2,382.88 | 5,209.84 | 4,947.45  [total delta-V:  13,340.17 m/sec]


Tooling for External Tank came out of studies done by US Air Force, prep. to executing plan to build SLS (Space Launch System, c. 1959-1961, Project Horizon), therefore weight estimate is within +/- 5% of real world example (tank just slightly larger than STS ET using larger diameter to remain within Launch Tower parameters)
Engines used:  5 F-1A | 2 M-1, ver. 1.1 | 400 k-lb AeroSpike (actually developed, real world testing data never released as system is still USAF classified, meaning high probability it was actually used).
Use of 18Nickel2400 (currently restricted for DOE/DOD use only) would reduce tank masses 62.5%.  Reusable mass addition would decrease, slightly (est. up to 15-20% of decrease)  Use of hardened electronics, post 1975 (when they officially became available) would decrease electronics mass est. -200 kg, or -125 kg if then-classified/just developed Ballistic Missile Inertial Navigator used, increasing electronics reliability from +8 to +15%, respectively.

Offline Burninate

  • Full Member
  • ****
  • Posts: 1134
  • Liked: 351
  • Likes Given: 73
Sea Dragon. -Bob Truax

Blue-sky options, huh?

A CH4-LOX powered Sea Dragon pushes up a 500 ton CH4 & small amount of LOX third stage, equipped with a fuel transfer system, horizontal clamps, and a modest CH4-LOX thruster.  One launch a month builds up an LEO propellant depot, with temperature moderated to ~95K by a sunshade, radiator, and CH4-LOX powered cryocooler system.  The thrust lines from the chemical thrusters remain clear.

The Apollo program snatches up nuclear engineers to improve a small implementation of the NERVA NTR with CH4 fuel.

Engineers take the design for the third stage tanks and build dedicated habitat modules, adding heavy insulation to diminish radiative heat loss, and erect a column of them starting from the dead center of the propellant depot, surrounded by tanks, out in the anti-thrustwards direction.  The first one, in the tank stacks, serves as a radiation / storm shelter (with CH4 serving as substantial protection) and water reservoir.  The last several, at the front of the craft, are equipped with radial docking ports for manned capsules & landers, and robotic arms / cranes to assemble lander missions.

The nuclear thermal rocket is mounted to the rear of the craft, to be used for low-thrust maneuvers, while the chemical thrusters stay in reserve for any high-thrust requirements.

Several copies of this station are placed into cycler orbits around any objects of interest, starting with Luna.
« Last Edit: 06/13/2014 11:19 AM by Burninate »

Offline Herb Schaltegger

I'm sure we all love Lobo's 7 paragraph, 2,000 word essays, but this really needs to be in Historical Spaceflight ("Missions that were or never will be"), not in the SLS section.
Ad astra per aspirin ...

Offline Lobo

  • Senior Member
  • *****
  • Posts: 6758
  • Spokane, WA
  • Liked: 555
  • Likes Given: 348
I'm sure we all love Lobo's 7 paragraph, 2,000 word essays, but this really needs to be in Historical Spaceflight ("Missions that were or never will be"), not in the SLS section.

Of course everyone enjoys those, why wouldn't they?  ;-)

But yes, I created this thread in the wrong section originally.  It should be in the historical section. However, I think a mod has to move it, right?

Offline Lobo

  • Senior Member
  • *****
  • Posts: 6758
  • Spokane, WA
  • Liked: 555
  • Likes Given: 348
Ahhh...there we go.  :-)

Tags: