Why can't we build the Saturn V again?

[William Graham]

MB123 - 24/3/2008  8:49 AM

You would need a Saturn IB?

Why not use the Saturn II or INT-20?

[pippin]

IIRC Saturn V was a VERY expensive vehicle.
I doubt that that would be more sustainable today than it was then.

[johng]

Astronautix.com lists the cost of a Saturn V as  $ 431M in 1967. That is the equivalent of $2.6 B today.  I had not realized it was nearly so much.

I suppose its a different argument as to whether we could have kept using the Saturn V vs whether we should be making new builds today.

I think we could have used the Saturn V as a production run in the 70's and the unit costs would have fallen. Much like the B-2 bomber. Build only 20 of them and they cost over $1B. If they would have buiilt the 132 units originally planned, they would have cost about $300M each.

Plus the design would have evolved to incorporate new technology.  American aerospace has a poor history of making good use of evolved design though.  Everyone wants a big, new thing - at least in politics.

If you think about in hindsight the money that was spent on shuttle and if it had been applied to a evolutionary project of series production for Saturn V lifters (and then Saturn V+, etc)  and Saturn 1 taxi launchers, a real space station could have been reality in the early 80s. Probably rehashing old thoughts though.

As for developing a Saturn now, the practical advantages are gone. The only good use would be as a preliminary design study to take Saturn V as a baseline and apply current technologies to it in a virtual/simulated design update to see where that puts you.

[MB123]

GW_Simulations - 24/3/2008 8:20 PM

MB123 - 24/3/2008 8:49 AM You would need a Saturn IB?

Why not use the Saturn II or INT-20?

Whichever - IMO the US govt's responsibility for the ISS neccesitates two vehicles - you cannot only have Saturn V you need another cheaper vehicle optimised for ISS/LEO crew transfer. (worst case no commercial system available for ISS ops, either way IMO NASA needs to have something available at all times)

How many of you have asked why we do not go for a RP-1/LO2 first stage? I have seen many. The answer is the technological heritage of the SRB - the SRB needs to be used in the new vehicle(s)

Really, if RP-1/L02 was used in the first stage Ares would be much closer to being a modern version of the Saturn system.

[mikeh]

johng - 24/3/2008 10:06 AM


Astronautix.com lists the cost of a Saturn V as $ 431M in 1967. That is the equivalent of $2.6 B today. I had not realized it was nearly so much.

According to Astronautix.com that was the cost per launch of the vehicle. Still considering that we spent $10B developing the Space Shuttle we could have bought and launched a bunch ( at least twenty) of Saturn V's.

I just don't buy the argument that the Saturn V was too "expensive" when spaceflight is inherently so. The fact is regardless of the expense, Congress and Nixon in 1970 did not approve the second production run of the Saturn V. This meant that NASA had nowhere to go or nothing to do in manned spaceflight after Apollo Applications.

It could be argued that the Space Shuttle "saved" the program. Saved U.S. manned spaceflight but condemned us to LEO for 36 years and counting.

I don't believe we could bring back the original but would like to see some "clean sheet" work.

[edkyle99]

johng - 24/3/2008  10:06 AM


Astronautix.com lists the cost of a Saturn V as  $ 431M in 1967. That is the equivalent of $2.6 B today.  I had not realized it was nearly so much.

It cost so much because it was so big.  Ares V, which will end up in the same size category, will probably cost the same, if not more.

 - Ed Kyle

[kraisee]

Fixed Costs per year approximately $1,200m + $800m for the EDS.   Flight costs $240m + 90m for the EDS.

Thus the costs will be about:

1 flight per year - ~$2,330m
2 flights per year - ~$1,330m each
3 flights per year - ~$997m each
4 flights per year - ~$830m each


Ares-I is additional to that.   $800m Fixed per year, $130m per unit:

1 flight per year - ~$930m
2 flights per year - ~$530m each
3 flights per year - ~$397m each
4 flights per year - ~$330m each

There are slight economies of scale on the flight costs, but at these low flight rates they aren't major so I'm leaving them out just for simplicity.

Ross.

[Takalok]

Well, if you look at the Constellation program, it pretty much is Saturn Part II - just as is being discussed here.  With the exception of the S-1C (first stage) and the S-II (second stage), it's just a Saturn / Apollo system with upgrades.  The Orion CM is an Apollo CM on steroids, which will use similar (same) ablative shielding, a launch escape tower, and a service module just like Saturn / Apollo.   Also, NASA is pretty up front about saying the ARES second stage is essentially a S-IVB.  The Lunar module looks about the same, but again, on steroids.  You know, hey, that's a pretty big concession to the 1970's.

However, just for fun, let's say you could restart Saturn / Apollo dirt cheap and get everything going etc. etc.  Now just imagine - 6 million pounds and 363 feet of kick-ass rocketry just standing there in all it's glory like some giant middle finger directed at all the people who've tried to do it "better."  Hmmmmmm.  You know, as much as I personally would love to see something like that, I think I'll have to settle for half a Saturn / Apollo rather than the whole works.  Politics and hubris are what they are.

However, IMHO, if you have to choose between Saturn S-IC and S-II and Ares, Saturn is the clear winner.  That being said, DIRECT 2.0 (again IMHO) beats both.

For those of you saying Saturn would have trouble servicing the ISS, may I remind all that several Saturn IB rockets flew crews to SkyLab, and also rendezvoused with the Russians.  Also a Saturn V put the whole 100 ton thing into orbit in one shot.  

If we had stuck with Saturn, we'd have saved not only a ton of money, but also two crews, and have done much, much more in space.  But, as I said, I'm happy with half a Saturn / Apollo than none at all.

[Jim]

Takalok - 25/3/2008  6:45 PM

1.  For those of you saying Saturn would have trouble servicing the ISS, may I remind all that several Saturn IB rockets flew crews to SkyLab, and also rendezvoused with the Russians.  Also a Saturn V put the whole 100 ton thing into orbit in one shot.  

no reminding needed, but you might need to be informed  that the CSM propellant and systems were offloaded to allow the IB to lift it into the necessary orbits.  Orion is much heavier.

[CFE]

The Apollo CSM could weigh as little as 14.7 mT for earth-orbit missions on the Sat IB.  For lunar missions, it weighed in at over 30 mT.

[CFE]

edkyle99 - 24/3/2008  10:10 PM

johng - 24/3/2008  10:06 AM


Astronautix.com lists the cost of a Saturn V as  $ 431M in 1967. That is the equivalent of $2.6 B today.  I had not realized it was nearly so much.

It cost so much because it was so big.  Ares V, which will end up in the same size category, will probably cost the same, if not more.

 - Ed Kyle

It's hard to say whether Ares v will be more expensive.  Those massive solids will be a major cost-driver, but Ares V has a lower engine count than Saturn V (even if they slip in the sixth core engine.)

[vt_hokie]

cneth - 23/3/2008  8:07 PM

To me, the analogy is to think about recreating a car like the 65 mustang again.  

Or maybe re-creating one of these!  

Here's an argument against heavy lift, though I don't necessarily endorse this view.  I'll defer to those more knowledgeable than I on the case for a HLV.

http://www.thespacereview.com/article/526/1

[Sid454]

It would be better to make an all new rocket vs bring back all the old manufacturing techniques used for the Saturn V.

Yes we could recreate it but we now have better tech for making the tanks and insulation for example.

We even have better engine options then the F1 used in the SC-I in the RS-84 and TR-107 engines which are modern engines both have higher ISP and the tr-107 is a lot simpler which means cheaper and more reliable.
They are not only in the same thrust class they are reusable which would allow at least the first stage to be made reusable  and would make it a lot more affordable then the Saturn which was very expensive.

Recovery could be done by adding a wing and jet engines as was proposed as a cost saving measure for a future upgrade to the sat V though this would have cost about 30% of it's payload.


Also SRBs are not very expensive either they are actually fairly cheap and reusable but low ISP which forces the core stage which would be equivalent the the SC-II to be larger and do more work.

In short an all new rocket could be made for the same price or less then recreating the 1960s vehicle that would outperform it by a very large margin.

[Sid454]

MB123 - 24/3/2008  3:49 AM

The Saturn V can do the whole job (trip to the moon) but how do you service the ISS?

You would need a Saturn IB? (Ares I)

You also need to use SRBs (seems to be a requirement)

Forget the IB and instead fly the Saturn V-B or V-C this would allow common launch platforms and towers as well as common engines between all vehicles.

If someone ever sets aside money to restart SLI and finished the TR-107 engine development maybe we could build a very similar vehicle based on the shuttle ET tanks.

Four of the TR-107s would be recovered for reuse the fifth engine would be lost of course.

http://en.wikipedia.org/wiki/Saturn_V-B

[Takalok]

Granted, S1B had only half the LEO of the proposed (pie in the sky?) Ares I.  But if you're going to stick an Orion capsule on a 1B, then you're really not talking Saturn any more.  

My rhetorical point was that classic Saturn / Apollo stack, a combination of two launchers (sort of like Ares I and V) could do the job.  

Nonetheless, I am a DIRECT 2.0 supporter, and recognize the limitations of the 1B.

Jim - 25/3/2008  7:55 PM

Takalok - 25/3/2008  6:45 PM

1.  For those of you saying Saturn would have trouble servicing the ISS, may I remind all that several Saturn IB rockets flew crews to SkyLab, and also rendezvoused with the Russians.  Also a Saturn V put the whole 100 ton thing into orbit in one shot.  

no reminding needed, but you might need to be informed  that the CSM propellant and systems were offloaded to allow the IB to lift it into the necessary orbits.  Orion is much heavier.

[Takalok]

I think one of the frustrating aspects of these debates is the comparison between a delivered system and a proposed system.  

The tantalizing attraction of Saturn is the simple fact that it is a delivered, operational system.  I mean, really, hasn't NASA already spent 2 billion dollars just testing the new SRB?  And it doesn't spec out.  Unless something gives, ARES is vaporware.

You also mentioned that a new rocket could be made for less than restarting Saturn.  I have to doubt that.  Certainly STS did not even come close to cost predictions, and Ares is following STS close behind.  Given that the Constellation program is "restarting" / redeveloping the Saturn S-IVB, the CM, the SM, and the LEM, we're really only talking about the lower half anyway.

Also, keep in mind the first two stages of Saturn were "dumb" in that they relied solely on the IU.  So if you did decide to use the S-IC and S-II stages (bolt for bolt, wire for wire), you could interface them with modern instrumentation.  

Lastly, and then I'll shut up, the Saturn V had an LEO of 118,000 kg while the proposed Ares V has an LEO of 130,000 kg.  There is no "very large margin" of performance there.  My prediction, if Ares V ever makes it to the launch pad, is that it will underperform Saturn and cost quite a bit more.

Sid454 - 26/3/2008  1:32 AM

It would be better to make an all new rocket vs bring back all the old manufacturing techniques used for the Saturn V.

Yes we could recreate it but we now have better tech for making the tanks and insulation for example.

We even have better engine options then the F1 used in the SC-I in the RS-84 and TR-107 engines which are modern engines both have higher ISP and the tr-107 is a lot simpler which means cheaper and more reliable.
They are not only in the same thrust class they are reusable which would allow at least the first stage to be made reusable  and would make it a lot more affordable then the Saturn which was very expensive.

Recovery could be done by adding a wing and jet engines as was proposed as a cost saving measure for a future upgrade to the sat V though this would have cost about 30% of it's payload.


Also SRBs are not very expensive either they are actually fairly cheap and reusable but low ISP which forces the core stage which would be equivalent the the SC-II to be larger and do more work.

In short an all new rocket could be made for the same price or less then recreating the 1960s vehicle that would outperform it by a very large margin.

[Rusty_Barton]

simonbp - 23/3/2008  9:30 AM

clongton - 23/3/2008  8:58 AM

Actually, if you read the history of the N-1, it wasn't the massive clustering that killed it, it was the Challenger syndrome, rush to launch before you should.

Well, that and the fact the first stage was so ridiculously complex that it almost guaranteed failure. Two of the four failures were due to just one of the 30 engines failing (and taking the vehicle with it), while the other two were due to an inept GNC system that either shut off 29/30 engines or, when the vehicle finally got up to speed, being unable to handle the massive roll torque induced by the basically tordial exhaust plume. Even if the Soviets had taken their time, the N1 was a fundamentally flawed design, and frankly beyond their capacity to make work.

Of course, to see what happened when they did take their time, look at Energia (which was approved the same day N1 was canceled)...

Simon

Was there a successful rocket that had more engines than the Saturn I with an S-IV second stage? Stage I had 8 engines and Stage II had 6 engines. If Von Braun had added the S-V third stage (Centaur?),  as shown in early plans, that would have added 2 more engines.

[edkyle99]

Takalok - 26/3/2008  6:25 AM

Granted, S1B had only half the LEO of the proposed (pie in the sky?) Ares I.  But if you're going to stick an Orion capsule on a 1B, then you're really not talking Saturn any more.  

My rhetorical point was that classic Saturn / Apollo stack, a combination of two launchers (sort of like Ares I and V) could do the job.  

Nonetheless, I am a DIRECT 2.0 supporter, and recognize the limitations of the 1B.

Here's something to consider.  The only Saturn that NASA could conceivably recreate (in an approximate way) today would be Saturn IB.  

The S-1B H-1 first stage engines are essentially still flying today as RS-27A engines on Delta II launch vehicles.  Granted the production line has closed, but the engines are still supported and presumably production could resume if enough money were assigned to the effort soon enough.

The S-1B tank tooling is long gone, but a new single big tank would be more efficient regardless.  Michoud has the space.    

The J-2 S-IVB engine is gone, but NASA is working on J-2X, which could power a new Saturn IB upper stage.  It is expected to be much more efficient (higher specific impulse) and to produce more thrust than the original J-2.  

No one builds S-IVB stages anymore, of course, but the planned Ares I upper stage is in the general vicinity of what would be needed, as is the new Ares I Instrument Unit.  

Remember that Saturn IB was a less than optimal design because its primary reason for existing was to test the Saturn V S-IVB stage and the Apollo CSM and LM payloads as early as possible.  (Saturn C-2, which was supposed to be the ultimate cluster booster, would have been Ares I class.)  Saturn IB carried the big SLA payload adapter that wasn't needed on most flights, for example, taking away from payload capability.

A "new" Saturn IB, fitted with a J-2X, would be able to boost more than 20 tonnes (possibly as much as 22 tonnes) to LEO.  

An alternative approach would be to build a new first stage powered by two RS-68 engines, topped by a J-2X powered second stage.  This machine, which I suppose could not be considered "Saturn derived" any more, would be able to boost 24 tonnes or more to LEO.

 - Ed Kyle

[Oersted]

One more thing to ponder regarding a Saturn class launch vehicle: it carried a huge space station into orbit with a diameter of no less than 6.7 meters! - With just five or six launches we could have had the ISS up there, and with nice big interior spaces.

Instead the limitations of the Shuttle bay and the Russian rockets have forced to us to a decade-long jigsaw puzzle of a construction project. Tiny little modules that look like a Salyut or a MIR. What's the fun of being weightless if you can hardly cavort around like the Skylab astronauts? - Sad really... Such a step back to abandon the Saturn class rocket.

[Oersted]

Just look!!