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SLS / Orion / Beyond-LEO HSF - Constellation => Heavy Lift Launch Vehicle (HLV/SLS) => Topic started by: Chris Bergin on 07/13/2015 02:02 PM

Title: SLS General Discussion Thread 2
Post by: Chris Bergin on 07/13/2015 02:02 PM
New Discussion Thread for SLS.

SLS Articles (lots of them):
http://www.nasaspaceflight.com/tag/sls/

L2 SLS:
http://forum.nasaspaceflight.com/index.php?board=48.0

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Do not post unless it's useful, on topic and interesting. This is not a place for the politics (that's in Space Policy), this is a place about the vehicle.
Title: Re: SLS General Discussion Thread 2
Post by: rayleighscatter on 07/20/2015 09:55 PM
A NASA rendering.
Title: Re: SLS General Discussion Thread 2
Post by: russianhalo117 on 07/21/2015 12:05 AM
A NASA rendering.

The ML shown above does not match the present design for the converted ML.
Title: Re: SLS General Discussion Thread 2
Post by: Zed_Noir on 07/21/2015 08:34 AM
A NASA rendering.

The ML shown above does not match the present design for the converted ML.
Hope NASA is not thinking of modifying the current ML or possibly even build a new ML. :o Doesn't make much financial sense with the current launch rate of record.
Title: Re: SLS General Discussion Thread 2
Post by: the_other_Doug on 07/21/2015 04:11 PM
A NASA rendering.

The ML shown above does not match the present design for the converted ML.
Hope NASA is not thinking of modifying the current ML or possibly even build a new ML. :o Doesn't make much financial sense with the current launch rate of record.

Well, if they're going to use the ML for SLS, it has to be modified from STS configuration.  I'm assuming you're trying to push an anti-SLS point, here, saying the ML shouldn't be modified because you don't think the SLS should ever fly.  But since it is being built and will fly, your point is moot.  They have to have at least two SLS-configured mobile launchers, one for backup in case the other gets stuck on a glitched C-T, as happened early in the Apollo flow.
Title: Re: SLS General Discussion Thread 2
Post by: Jim on 07/21/2015 04:15 PM
Hope NASA is not thinking of modifying the current ML or possibly even build a new ML. :o Doesn't make much financial sense with the current launch rate of record.

Well, if they're going to use the ML for SLS, it has to be modified from STS configuration.  I'm assuming you're trying to push an anti-SLS point, here, saying the ML shouldn't be modified because you don't think the SLS should ever fly.  But since it is being built and will fly, your point is moot.  They have to have at least two SLS-configured mobile launchers, one for backup in case the other gets stuck on a glitched C-T, as happened early in the Apollo flow.

There is only one ML and it was built for Ares I and is being converted for SLS.  The three shuttle MLP's are not being used for anything.
Title: Re: SLS General Discussion Thread 2
Post by: the_other_Doug on 07/21/2015 04:22 PM
Hope NASA is not thinking of modifying the current ML or possibly even build a new ML. :o Doesn't make much financial sense with the current launch rate of record.

Well, if they're going to use the ML for SLS, it has to be modified from STS configuration.  I'm assuming you're trying to push an anti-SLS point, here, saying the ML shouldn't be modified because you don't think the SLS should ever fly.  But since it is being built and will fly, your point is moot.  They have to have at least two SLS-configured mobile launchers, one for backup in case the other gets stuck on a glitched C-T, as happened early in the Apollo flow.

There is only one ML and it was built for Ares I and is being converted for SLS.  The three shuttle MLP's are not being used for anything.

Gotcha, thanks for the clarification.  Interesting, I would have thought that they would have used the MLPs as the basis for the new MLs, just as they used the Apollo MLs as the basis for the MLPs.  I'm also a little surprised they would only plan on having one of them, since as I say there was an Apollo ML that got stuck off to the side of 39A for several months when its C-T failed after a test drive of just the ML to the pad, and needed to be repaired in-place, back in 1968, IIRC.
Title: Re: SLS General Discussion Thread 2
Post by: darkenfast on 07/22/2015 05:44 AM
This rendering still has the phony "Saturn V" looking paint-job as well.  Somebody at NASA just won't let that one go away.
Title: Re: SLS General Discussion Thread 2
Post by: Spacely on 07/22/2015 04:19 PM
How major were the modifications to turn the Ares I ML into one for SLS? Was it a total rebuild?
Title: Re: SLS General Discussion Thread 2
Post by: the_other_Doug on 07/22/2015 06:56 PM
When we speak of the Ares 1 ML, we aren't talking about the one they used to launch Ares 1X, are we?  I thought that was a standard Shuttle MLP and the Ares 1X was positioned over one of the SRB fire holes.

I'm taking it that there was an ML that was being constructed for Ares 1 that was mostly finished when the Ares program was canceled?  And this is what is being modified to support SLS?

Sorry if I wasn't following the construction of Areas program support structures all that closely in the mid-aughts.  Had other things that were pre-occupying me at the time...
Title: Re: SLS General Discussion Thread 2
Post by: Jim on 07/22/2015 07:31 PM

I'm taking it that there was an ML that was being constructed for Ares 1 that was mostly finished when the Ares program was canceled?  And this is what is being modified to support SLS?


Yes and yes.
Title: Re: SLS General Discussion Thread 2
Post by: Star One on 07/22/2015 08:24 PM
NASA Developing Solar-sailing Cubesats for Inaugural SLS Launch

Quote
WASHINGTON — NASA is developing a pair of solar-sailing, science-collecting cubesats that will hitch a ride on the Space Launch System’s inaugural July 2018 launch.

The two spacecraft, currently envisioned as six-unit cubesats with deployable solar sails, will travel beyond low Earth orbit to conduct scientific observations of an asteroid and the moon.

NASA’s Near Earth Asteroid Scout, or NEA Scout, cubesat will conduct a 2020 flyby of asteroid 1991 VG to determine its size, movement and chemical composition.

The aptly named Lunar Flashlight cubesat will sail into a polar orbit around the moon by early 2019 then use its solar sail as a mirror, reflecting sunlight onto the cold, dark regions of the lunar poles. Once the polar regions are illuminated, onboard sensors will help determine the composition and distribution of frozen water and other volatiles hidden in the moon’s shadows.

http://spacenews.com/nasa-developing-solar-sailing-cubesats-for-inaugural-sls-launch/#sthash.0Ta4ceDh.dpuf
Title: Re: SLS General Discussion Thread 2
Post by: Vultur on 08/10/2015 04:00 AM
That will be the EM-1 launch, right? July 2018 is the current date for that?

Also, what's the current plan for the advanced boosters? I've read several different things and I'm not clear on which is right.
Title: Re: SLS General Discussion Thread 2
Post by: Endeavour_01 on 08/10/2015 05:14 PM
That will be the EM-1 launch, right? July 2018 is the current date for that?

Correct on both counts.

Quote
Also, what's the current plan for the advanced boosters? I've read several different things and I'm not clear on which is right.

Right now NASA is proceeding with SLS Block I for EM-1 (Core stage plus current boosters plus ICPS upper stage) and going immediately to Block IB (Core stage plus current boosters plus EUS upper stage). Advanced boosters will come after Block IB (so late 2020s). There are a couple of way NASA could go with this. They could go with Block II (Core stage plus advanced boosters plus another upper stage) or Block IIB (Core stage plus advanced boosters plus EUS upper stage).
Title: Re: SLS General Discussion Thread 2
Post by: brickmack on 08/11/2015 12:28 AM
Quote
Also, what's the current plan for the advanced boosters? I've read several different things and I'm not clear on which is right.

Right now NASA is proceeding with SLS Block I for EM-1 (Core stage plus current boosters plus ICPS upper stage) and going immediately to Block IB (Core stage plus current boosters plus EUS upper stage). Advanced boosters will come after Block IB (so late 2020s). There are a couple of way NASA could go with this. They could go with Block II (Core stage plus advanced boosters plus another upper stage) or Block IIB (Core stage plus advanced boosters plus EUS upper stage).

Probably more like early-mid 2020s. Last I heard they've only got enough SRB parts leftover from the shuttle to make about 10 boosters (so 5 SLS flights). 1 pair would be used for EM 1, and the next flight would be in 2021 or maybe 2020 if we're lucky, at about 1 launch a year, so that puts 2025 as the latest they could do a launch before switching to advanced boosters, unless they restart production (not exactly cheap). They've got the equipment to fuel and stack them, but thats it
Title: Re: SLS General Discussion Thread 2
Post by: Vultur on 08/11/2015 01:17 AM
Thank you.

That will be the EM-1 launch, right? July 2018 is the current date for that?

Correct on both counts.

Cool. Wikipedia says September 30 so that's why I was surprised.
Title: Re: SLS General Discussion Thread 2
Post by: Endeavour_01 on 08/11/2015 08:48 PM

Probably more like early-mid 2020s. Last I heard they've only got enough SRB parts leftover from the shuttle to make about 10 boosters (so 5 SLS flights). 1 pair would be used for EM 1, and the next flight would be in 2021 or maybe 2020 if we're lucky, at about 1 launch a year, so that puts 2025 as the latest they could do a launch before switching to advanced boosters, unless they restart production (not exactly cheap). They've got the equipment to fuel and stack them, but thats it

I was under the impression that it was 10 pairs of boosters. If not then you are correct.
Title: Re: SLS General Discussion Thread 2
Post by: Raj2014 on 08/11/2015 09:29 PM
Does anyone know the exact and accurate dimensions of the SLS block 1B? Has NASA discussed what they would do after EM-2? I know they have plans for ARM, Europa and then Mars but do they have plans before ARM of in between?  When will NASA use the USA? Has NASA thought of using aerospike engines for the core stage instead? I read that aerospike engines have had testing and are ideal for launches from the ground to LEO.
Title: Re: SLS General Discussion Thread 2
Post by: Jim on 08/12/2015 12:04 AM
Has NASA thought of using aerospike engines for the core stage instead?

No, the whole point of the SLS design is to use derivatives of shuttle propulsion elements (SSME and SRB's).    SLS will fly only one to two times a year.  Not enough to justfiy a new engine development program.

These questions are the same as those on Orion.  SLS and Orion are not designed to push the state of the art or to reduce operational costs.
Title: Re: SLS General Discussion Thread 2
Post by: Raj2014 on 08/12/2015 11:36 AM
Has NASA thought of using aerospike engines for the core stage instead?

No, the whole point of the SLS design is to use derivatives of shuttle propulsion elements (SSME and SRB's).    SLS will fly only one to two times a year.  Not enough to justfiy a new engine development program.

These questions are the same as those on Orion.  SLS and Orion are not designed to push the state of the art or to reduce operational costs.

Interesting, I also read that during the use of the SLS it will be improved, is this true? Why not reduce operational costs? I understand with what you have said Jim, that they are re-using technologies but will that not reduce the costs as well?
Title: Re: SLS General Discussion Thread 2
Post by: notsorandom on 08/12/2015 12:55 PM
Has NASA thought of using aerospike engines for the core stage instead?

No, the whole point of the SLS design is to use derivatives of shuttle propulsion elements (SSME and SRB's).    SLS will fly only one to two times a year.  Not enough to justfiy a new engine development program.

These questions are the same as those on Orion.  SLS and Orion are not designed to push the state of the art or to reduce operational costs.

Interesting, I also read that during the use of the SLS it will be improved, is this true? Why not reduce operational costs? I understand with what you have said Jim, that they are re-using technologies but will that not reduce the costs as well?
SLS is not going to be doing anything very revolutionary. There are some optimizations already being incorporated. An example would be the first new batch of RS-25 engines will have a new engine controller and less person hour intensive manufacturing. I'd expect like the Shuttle and even Saturn V that SLS will be upgraded over its lifetime. There is still likely to be some sort of advanced booster competition in the future where new technologies may be used. Also the EUS is likely to use RL-10 engines at first but may use another engine. It may also use composite tanks. Those things though are not finalized as the priority is getting the first two launched done.
Title: Re: SLS General Discussion Thread 2
Post by: BrightLight on 08/18/2015 01:37 AM
http://www.nasaspaceflight.com/2015/08/asap-status-sls-orion-red-risks/

Really good article Chris, highly informative and also positive, I'm glad to see SLS is moving past CxP and maybe into flight status!
Title: Re: SLS General Discussion Thread 2
Post by: clongton on 08/18/2015 02:01 AM
Good article. Although short it provided a fairly meaty summary of where the SLS is currently on its journey to flight status. You noted that ASAP still has a concern about schedule driving decisions that might be detrimental to crew safety. Personally I don't think that will be a problem. Pressure schedule can result when things are getting tight and there is no sign of any of that happening with the program. If anything SLS seems to be having a fairly easy time of it, which isn't really surprising as this is the evolutionary path that the Shuttle designers envisioned would be taken to field a true HLV based on the STS design. Over the years several designs began this way, only to fall victim to various circumstances. The two most recent were the NLS and DIRECT, both of which followed this pre-determined "path of least resistance" to an operational HLV. Alas it was not to be for either vehicle. But this third attempt may be the charm. SLS has gotten the furthest along of any of them, even passing where CxP was when it was cancelled, and has yet to encounter a single major problem with the design. We just might get to see the evolved STS HLV fly yet. One thing it has going for it, and a very big thing at that, is that there is plenty of budgetary support for this program, dispite the dearth of payloads to date, besides Orion, that would take advantage of its massive capability. But if SLS actually gets to the finish line and flies, I'm pretty sure that payloads won't be too far behind.

Once again - great article. Thank you.
Title: Re: SLS General Discussion Thread 2
Post by: Rocket Science on 08/18/2015 02:16 AM
Thanks for the great article Chris. The political will and the funding is there to build it so we should try to get behind it despite its mission uncertainty.  Interesting the free hydrogen is still an issue perhaps some simple blowers to move it from under the vehicle along with the sparklers might do the trick...
Title: Re: SLS General Discussion Thread 2
Post by: Chris Bergin on 08/18/2015 10:42 AM
Thanks very much! :)
Title: Re: SLS General Discussion Thread 2
Post by: sdsds on 08/20/2015 07:11 AM
Interesting the free hydrogen is still an issue

Thanks for pointing that out. In truth though has gaseous hydrogen ever been a concern for any group other than ASAP? In what way has the concern ever been quantified? I ask because sure, fireballs around e.g. Delta IV liftoffs have looked frightening, but have they ever had an impact on mission success? In particular for crew safety, suppose some disasterous contingency scenario were to occur -- isn't that what pad abort systems are designed to handle?
Title: Re: SLS General Discussion Thread 2
Post by: Rocket Science on 08/20/2015 12:46 PM
Interesting the free hydrogen is still an issue

Thanks for pointing that out. In truth though has gaseous hydrogen ever been a concern for any group other than ASAP? In what way has the concern ever been quantified? I ask because sure, fireballs around e.g. Delta IV liftoffs have looked frightening, but have they ever had an impact on mission success? In particular for crew safety, suppose some disasterous contingency scenario were to occur -- isn't that what pad abort systems are designed to handle?
During the 70’s when the Shuttle was being designed there was concern that one of the SRBs could prematurely ignite causing a disaster. It could be similar thinking and precaution at play here... Agreed, at least they have a pad abort ability now...
Title: Re: SLS General Discussion Thread 2
Post by: notsorandom on 08/20/2015 01:12 PM
Interesting the free hydrogen is still an issue

Thanks for pointing that out. In truth though has gaseous hydrogen ever been a concern for any group other than ASAP? In what way has the concern ever been quantified? I ask because sure, fireballs around e.g. Delta IV liftoffs have looked frightening, but have they ever had an impact on mission success? In particular for crew safety, suppose some disastrous contingency scenario were to occur -- isn't that what pad abort systems are designed to handle?
Following STS-41-D's pad abort free hydrogen that leaked from the engine cause a fire. Had the normal evacuation procedure been followed the crew would have encountered the fire. While Orion has a LES and Discovery didn't there are still situations where it would be preferable to get the crew out of the capsule rather than activate the LES.
Title: Re: SLS General Discussion Thread 2
Post by: DaveS on 08/20/2015 01:32 PM
Interesting the free hydrogen is still an issue

Thanks for pointing that out. In truth though has gaseous hydrogen ever been a concern for any group other than ASAP? In what way has the concern ever been quantified? I ask because sure, fireballs around e.g. Delta IV liftoffs have looked frightening, but have they ever had an impact on mission success? In particular for crew safety, suppose some disastrous contingency scenario were to occur -- isn't that what pad abort systems are designed to handle?
Following STS-41-D's pad abort free hydrogen that leaked from the engine cause a fire. Had the normal evacuation procedure been followed the crew would have encountered the fire. While Orion has a LES and Discovery didn't there are still situations where it would be preferable to get the crew out of the capsule rather than activate the LES.
They did change the procedures after the 41D RSLS abort to include the immediate activation of the Base Heat Shield (BHS) water deluge system (this is the water system that showers the engines after a RSLS abort). For 41D and earlier, the procedure was a manual activation and it was only in short bursts. After 41D they made it automatic as well as continues which kept the engines and the aft watered down for a good 15 minutes or so.
Title: Re: SLS General Discussion Thread 2
Post by: notsorandom on 08/20/2015 03:10 PM
Interesting the free hydrogen is still an issue

Thanks for pointing that out. In truth though has gaseous hydrogen ever been a concern for any group other than ASAP? In what way has the concern ever been quantified? I ask because sure, fireballs around e.g. Delta IV liftoffs have looked frightening, but have they ever had an impact on mission success? In particular for crew safety, suppose some disastrous contingency scenario were to occur -- isn't that what pad abort systems are designed to handle?
Following STS-41-D's pad abort free hydrogen that leaked from the engine cause a fire. Had the normal evacuation procedure been followed the crew would have encountered the fire. While Orion has a LES and Discovery didn't there are still situations where it would be preferable to get the crew out of the capsule rather than activate the LES.
They did change the procedures after the 41D RSLS abort to include the immediate activation of the Base Heat Shield (BHS) water deluge system (this is the water system that showers the engines after a RSLS abort). For 41D and earlier, the procedure was a manual activation and it was only in short bursts. After 41D they made it automatic as well as continues which kept the engines and the aft watered down for a good 15 minutes or so.
If I'm not mistaken they also added butcher paper in various places so that the cameras on and around the pad could see if there were a fire.
Title: Re: SLS General Discussion Thread 2
Post by: DaveS on 08/20/2015 03:53 PM
Interesting the free hydrogen is still an issue

Thanks for pointing that out. In truth though has gaseous hydrogen ever been a concern for any group other than ASAP? In what way has the concern ever been quantified? I ask because sure, fireballs around e.g. Delta IV liftoffs have looked frightening, but have they ever had an impact on mission success? In particular for crew safety, suppose some disastrous contingency scenario were to occur -- isn't that what pad abort systems are designed to handle?
Following STS-41-D's pad abort free hydrogen that leaked from the engine cause a fire. Had the normal evacuation procedure been followed the crew would have encountered the fire. While Orion has a LES and Discovery didn't there are still situations where it would be preferable to get the crew out of the capsule rather than activate the LES.
They did change the procedures after the 41D RSLS abort to include the immediate activation of the Base Heat Shield (BHS) water deluge system (this is the water system that showers the engines after a RSLS abort). For 41D and earlier, the procedure was a manual activation and it was only in short bursts. After 41D they made it automatic as well as continues which kept the engines and the aft watered down for a good 15 minutes or so.
If I'm not mistaken they also added butcher paper in various places so that the cameras on and around the pad could see if there were a fire.
That was only on the aft vertical struts of the ET. They also installed alot more IR cameras. Before 41D they only had a few.
Title: Re: SLS General Discussion Thread 2
Post by: Gordon C on 08/22/2015 10:41 PM
Has NASA thought of using aerospike engines for the core stage instead?

No, the whole point of the SLS design is to use derivatives of shuttle propulsion elements (SSME and SRB's).    SLS will fly only one to two times a year.  Not enough to justfiy a new engine development program.

These questions are the same as those on Orion.  SLS and Orion are not designed to push the state of the art or to reduce operational costs.

If SLS were being built without want for use of STS hardware, would it stage sequentially like Saturn V did?  Or is there benefit to horizontal staging where even in absence of STS hardware it would look like Delta IV with boosters on the side of a big core?
Title: Re: SLS General Discussion Thread 2
Post by: sdsds on 08/23/2015 12:11 AM
If SLS were being built without want for use of STS hardware, would it stage sequentially like Saturn V did?

In late 2010, NASA engaged in a "Requirements Analysis Cycle" evaluating just this kind of question. See:
http://www.nasaspaceflight.com/2010/12/heft-sls-hlv-design-decision-april-2011/

Ed Kyle wrote more about this:
http://www.spacelaunchreport.com/sls4.html

Of course the decision is now "water under the bridge," but your hypothetical question nonetheless deserves some sort of answer!
Title: Re: SLS General Discussion Thread 2
Post by: Proponent on 08/24/2015 05:37 AM
If SLS were being built without want for use of STS hardware, would it stage sequentially like Saturn V did?  Or is there benefit to horizontal staging where even in absence of STS hardware it would look like Delta IV with boosters on the side of a big core?

In addition to sdsds's pointer to the series-staged RAC-2 design, first principles suggest you would use traditional series staging rather than parallel staging for a clean-sheet expendable vehicle.  One of the good things about a traditional first stage is that weight is not critical.  Typically each kilogram added to the first-stage's structure reduces the LEO payload by only about 0.1 kg, because the stage isn't carried very far.  In a core-plus boosters design, on the other hand, the core is carried all the way to orbit, so each kilogram of added mass reduces the payload by 1 kg.  Hence, the whole core is a weight-critical structure, and its cost will tend to reflect that.

Another problem with parallel staging is that the core's engines need to operate at sea-level and, with high efficiency, in a vacuum.  This is perfectly possible, as the SSME proved, but it's not cheap.

A while ago I did a back-of-the-envelope numerical comparison (see the attachment) (https://forum.nasaspaceflight.com/index.php?topic=28796.msg895065#msg895065) of series and parallel staging to illustrate these arguments.

Title: Re: SLS General Discussion Thread 2
Post by: redliox on 09/02/2015 09:32 PM
Couple of links; first, this appears to be a recent SLS blog:
https://blogs.nasa.gov/Rocketology/

Second, the NASA Advisory Council link was fixed and this PowerPoint deck (presented at the end of July at the JPL meeting) has some good information on development/status and recent schedule forecasts:
http://www.nasa.gov/sites/default/files/files/2-Hill-Exploration-Systems-Development-Status-ESD-Status-NAC_Hill-July-28_Final.pdf

The progress looks encouraging.  Reading into it, it looks like both Orion and SLS will be built and ready by the final quarter of 2017 if all goes well.  They mention mating the capsule with ESA's service module in 2017 but they don't elaborate much further on its progress; that makes me desire details on ESA's progress - the last thing we need is a delay caused by European and American contractors misinterpreting each other's Metric and Imperial/English measurements (which would be the least of more serious issues).  Hopefully minimal delays or issues occur and keep EM-1 ready for summer of '18.  :)
Title: Re: SLS General Discussion Thread 2
Post by: clongton on 09/03/2015 01:15 AM
When completed, SLS, NASA's new rocket, will be one of the biggest, most powerful rockets ever built.

Having been around when the Saturn-V was flying I am constantly irritated when I see statements like this. Everybody is always insisting that we compare apples to apples rather than apples to oranges, EXCEPT when it comes to showcasing the SLS - as if there is nothing else out there that compares favorably. Here's where us "old-timers" step in to set the record straight and keep the SLS proponents honest.

The configuration of SLS above includes two (2) solid side boosters, and then they compare it to the Saturn-V without side boosters. Well for everyone's information there were side booster versions of the Saturn-V being developed that used a pair of 120 inch diameter solids strapped to the side of the core. This vehicle would deliver in excess of 180 tonnes to LEO. If one wants to compare the SLS to Saturn, then compare it to this side-boosted variant. If one does not want to compare to this Saturn variant then delete the SLS solids and compare core to core. Keep it apples to apples. Either way SLS will always come out less than the Saturn.

For those who would say that the solid-boosted Saturn never actually existed I would say that neither does an actual SLS. But I would say that both vehicles were at a similar stage of development, with metal being bent for bothedit. That makes them completely comparable.

I'm not bashing the SLS by any means. What I am bashing is misleading statements about the SLS.

Edit: added clarifying phrase
Title: Re: SLS General Discussion Thread 2
Post by: RonM on 09/03/2015 02:27 AM
When completed, SLS, NASA's new rocket, will be one of the biggest, most powerful rockets ever built.

Having been around when the Saturn-V was flying I am constantly irritated when I see statements like this. Everybody is always insisting that we compare apples to apples rather than apples to oranges, EXCEPT when it comes to showcasing the SLS - as if there is nothing else out there that compares favorably. Here's where us "old-timers" step in to set the record straight and keep the SLS proponents honest.

The configuration of SLS above includes two (2) solid side boosters, and then they compare it to the Saturn-V without side boosters. Well for everyone's information there were side booster versions of the Saturn-V being developed that used a pair of 120 inch diameter solids strapped to the side of the core. This vehicle would deliver in excess of 180 tonnes to LEO. If one wants to compare the SLS to Saturn, then compare it to this side-boosted variant. If one does not want to compare to this Saturn variant then delete the SLS solids and compare core to core. Keep it apples to apples. Either way SLS will always come out less than the Saturn.

For those who would say that the solid-boosted Saturn never actually existed I would say that neither does an actual SLS. But I would say that both vehicles were at a similar stage of development. That makes them completely comparable.

I'm not bashing the SLS by any means. What I am bashing is misleading statements about the SLS.

While I see your point, it's not valid under these circumstances.

Metal is being bent, the boosters and engines are real, SLS will launch in less than three years. You can't say SLS doesn't exist.
Title: Re: SLS General Discussion Thread 2
Post by: Steven Pietrobon on 09/03/2015 10:20 AM
For those who would say that the solid-boosted Saturn never actually existed I would say that neither does an actual SLS. But I would say that both vehicles were at a similar stage of development. That makes them completely comparable.

There is no need to compare with a solid boosted version of Saturn V. The Block I (70 t) and Block IB (93 t) versions of SLS are both below the Saturn V (118 t). These two versions are the only ones that NASA is currently planning on building. If NASA does decide to build the full Block II version of SLS (130 t), then that will indeed be the most powerful, but for now, they are definitely not building the world's most powerful rocket.
Title: Re: SLS General Discussion Thread 2
Post by: woods170 on 09/03/2015 11:49 AM
When completed, SLS, NASA's new rocket, will be one of the biggest, most powerful rockets ever built.

Having been around when the Saturn-V was flying I am constantly irritated when I see statements like this.
<snip>
I'm not bashing the SLS by any means. What I am bashing is misleading statements about the SLS.
Emphasis mine.

There is nothing misleading about the SLS statement. It does not say that SLS is THE most powerful rocket ever build. It specifically states that SLS is ONE of the most powerful rockets ever build. And that is correct. SLS in it's 70 mT and 93 mT incarnations stands among the most powerful rockets in the world, surpassed only by N-1, Energia and Saturn V.
Title: Re: SLS General Discussion Thread 2
Post by: MarcAlain on 09/03/2015 04:05 PM
KSC shopping for Liquid Hydrogen solution ahead of SLS debut
http://www.nasaspaceflight.com/2015/03/ksc-shopping-lh2-ahead-sls-launch/

They should just replace the entire first stage with a RP1 fueled, F1 engine cluster.
Title: Re: SLS General Discussion Thread 2
Post by: RocketmanUS on 09/13/2015 08:21 PM
What is the cost for one additional flight of SLS?
Comparing one launch of SLS compared to one launch of Delta IVH.
So if SLS does become available then could it launch DIVH class payloads?
Would this same any money by being able to retire DIVH sooner before Vulcan/ACES could replace it?
Title: Re: SLS General Discussion Thread 2
Post by: Endeavour_01 on 09/13/2015 08:33 PM
What is the cost for one additional flight of SLS?

Somewhere between $500 Million and $1 Billion. I believe Delta IVH is in the $300 Million range.

Quote
So if SLS does become available then could it launch DIVH class payloads?

Oh it could definitely handle DIVH class payloads. It wouldn't be even close to the best use for SLS in my opinion but it could physically do it.

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Would this save any money by being able to retire DIVH sooner before Vulcan/ACES could replace it?

Not really. Remember SLS only has two flights on its manifest through 2021 and both of them are NASA dedicated. By 2021 Vulcan should be flying and Falcon Heavy should be online in the next year or so.

IMHO SLS should be dedicated to launching NASA payloads. That avoids competition with the commercial sector and frees up launches for deep space exploration (human and robotic).
Title: Re: SLS General Discussion Thread 2
Post by: arachnitect on 09/13/2015 08:45 PM
What is the cost for one additional flight of SLS?

Somewhere between $500 Million and $1 Billion. I believe Delta IVH is in the $300 Million range.

Closer to $400M for D-IVH
So if SLS does become available then could it launch DIVH class payloads?

Oh it could definitely handle DIVH class payloads. It wouldn't be even close to the best use for SLS in my opinion but it could physically do it.


SLS can't do polar orbits
Title: Re: SLS General Discussion Thread 2
Post by: Endeavour_01 on 09/13/2015 08:50 PM

Closer to $400M for D-IVH

Thanks for the correction. I was basing it off the EFT-1 Orion cost which was $330 Million.

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SLS can't do polar orbits

Did not remember that. Thanks.
Title: Re: SLS General Discussion Thread 2
Post by: Coastal Ron on 09/13/2015 09:03 PM
IMHO SLS should be dedicated to launching NASA payloads.

Which is pretty much the default anyways.  The DoD/NRO would not want to use the SLS unless they had no options - and they will have options.

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That avoids competition with the commercial sector...

Commercial capabilities will always be potential competitors to the SLS, since unless commercial options are specifically eliminated as options (i.e. by law), their lower prices will always present "what if" situations to those that propose NASA missions - that SLS launches are not free, and commercial launch prices are going down.

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...and frees up launches for deep space exploration (human and robotic).

What's to free up?  NASA already has the capability to build two SLS per year, and the cost to build two SLS-sized payloads per year would require a HUGE increase in NASA's development and operational budget.  Assuming NASA doesn't get a budget bump, and assuming the ISS stays operational through 2024, NASA won't be able to afford even one launch per year.  Based on that, of course they would jump at the chance for someone else to use the SLS... but that's unlikely to happen, for a number of reasons.
Title: Re: SLS General Discussion Thread 2
Post by: 93143 on 09/13/2015 09:36 PM
What is the cost for one additional flight of SLS?
Somewhere between $500 Million and $1 Billion.

No, $1B is too high.  Assuming the program exists and can handle the extra flight, an SLS launch by itself cannot reasonably be expected to add more than about $500M to the program's cost, probably below $400M, could be below $300M.

You're talking about the operations cost of existing technology, and not the part that depends strongly on flight rate either.  Moreover, basically all of the changes that have the potential to significantly affect cost are cost-saving measures.  The marginal cost of launching a Shuttle-derived LV is not going to balloon like the development cost of a cutting-edge space telescope.

Now, what NASA would charge for such a launch may be a different story; they might try to take advantage of the situation to offload some of their fixed costs, as if they were a commercial operation...  Shuttle didn't, back in the day, but that was then...

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...and frees up launches for deep space exploration (human and robotic).
What's to free up?  NASA already has the capability to build two SLS per year, and the cost to build two SLS-sized payloads per year would require a HUGE increase in NASA's development and operational budget.  Assuming NASA doesn't get a budget bump, and assuming the ISS stays operational through 2024, NASA won't be able to afford even one launch per year.

Human missions shouldn't require brand-new hardware development for every flight.  And there's at least one option that only requires one new piece of hardware to start and would remain worthwhile launching as often as twice a year or more.  The increase required would not be "HUGE", certainly not in the way you've claimed in the past.

I think there's more flex in the budget than you realize.  Once SLS and Orion (and Commercial Crew) transition to ops, the cost will come down, and a wedge for hardware development will open up.  Furthermore, SLS isn't all about huge payloads to LEO; one reason the science people are interested is that it can provide a large amount of delta-V to a quite ordinary-sized probe.
Title: Re: SLS General Discussion Thread 2
Post by: RocketmanUS on 09/14/2015 12:58 AM
OK, so then polar orbits would be the issue for SLS to take over DIVH launches till Vulcan/ACES could be ready, not the launch price.
Title: Re: SLS General Discussion Thread 2
Post by: 93143 on 09/14/2015 01:21 AM
I suspect that the quoted launch price for DIVH is not the incremental cost to the U.S. Government of procuring the vehicle.  I imagine it includes a bunch of fixed costs.  So that would be an apples-to-oranges comparison; the cost to the USG to procure an additional SLS flight given a running program with enough headroom to allow the launch might only be a few hundred million, but if I'm right the marginal cost of the Delta IV Heavy would be lower than that.

So this comparison is only really useful if you're in a situation where your budget would take the full hit of the DIVH price but only the marginal cost of an SLS (it might be possible to get the SMD into such a situation, but the DoD probably isn't).
Title: Re: SLS General Discussion Thread 2
Post by: Brovane on 09/14/2015 02:14 AM
I suspect that the quoted launch price for DIVH is not the incremental cost to the U.S. Government of procuring the vehicle.  I imagine it includes a bunch of fixed costs.  So that would be an apples-to-oranges comparison; the cost to the USG to procure an additional SLS flight given a running program with enough headroom to allow the launch might only be a few hundred million, but if I'm right the marginal cost of the Delta IV Heavy would be lower than that.

So this comparison is only really useful if you're in a situation where your budget would take the full hit of the DIVH price but only the marginal cost of an SLS (it might be possible to get the SMD into such a situation, but the DoD probably isn't).

You seriously think the incremental cost of the SLS is only a few hundred million dollars? 
Title: Re: SLS General Discussion Thread 2
Post by: Endeavour_01 on 09/14/2015 02:37 AM
No, $1B is too high.  Assuming the program exists and can handle the extra flight, an SLS launch by itself cannot reasonably be expected to add more than about $500M to the program's cost, probably below $400M, could be below $300M.

I agree with you wholeheartedly that most SLS cost estimates are ridiculously overestimated (I think $500 Million is a little too low though). I was trying to give Rocketman a range of realistically imaginable costs.

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You're talking about the operations cost of existing technology, and not the part that depends strongly on flight rate either.  Moreover, basically all of the changes that have the potential to significantly affect cost are cost-saving measures.  The marginal cost of launching a Shuttle-derived LV is not going to balloon like the development cost of a cutting-edge space telescope.

Agreed. A lot of people seem to think that SLS costs are absurd. The fact is that annual developmental costs of both SLS and Orion have been $1-2 Billion lower than the cost to run the space shuttle every year. That is a drastic improvement and for much more capability.

I've run the numbers several times. The whole SLS/Orion program (including things like hab modules and landers) is going to have lower costs than the shuttle program.

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The increase required would not be "HUGE", <snip>

Exactly. NASA was able to run shuttle concurrently with the construction and maintenance of ISS. Increases to the budget don't have to be extreme.
Title: Re: SLS General Discussion Thread 2
Post by: Coastal Ron on 09/14/2015 03:53 AM
No, $1B is too high.  Assuming the program exists and can handle the extra flight, an SLS launch by itself cannot reasonably be expected to add more than about $500M to the program's cost, probably below $400M, could be below $300M.

I agree with you wholeheartedly that most SLS cost estimates are ridiculously overestimated. I was trying to give Rocketman a range of realistically imaginable costs.

And in the absence of real cost numbers (which NASA is very behind on providing) comparisons to existing systems are one way to help estimate costs.

For instance, Delta IV Heavy is a vehicle that is in constant production by virtue of the Delta IV it's based on being flown about three times per year (avg flights/year going back to 2009).  The flight ops team is also shared with Atlas V to a certain degree, so the overhead is lower than if it had to absorb all the overhead itself (like SLS will have to do).

The SLS, from what I can tell, is probably at least twice the dry mass of Delta IV Heavy, and the Delta IV Heavy is a pretty simple design to start with (SLS not as much) - mass is a good indicator of how much manufacturing effort has to be done.  Both launchers have to account for contractor profit within their overall costs to end users, with ULA adding their own profit at the launch (which the SLS would not have), and the SLS having to pay profit to everyone that provides pieces of the SLS, the contractor that will assemble the SLS, and the contractor that will provide launch operations (they might be the same, I'm just breaking them out).

So assuming that the SLS will be the same cost as the Delta IV Heavy, or even possibly less, doesn't look right.

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The fact is that annual developmental costs of both SLS and Orion have been $1-2 Billion lower than the cost to run the space shuttle every year. That is a drastic improvement and for much more capability.

What the annual costs are is irrelevant, only the total cost is relevant.

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I've run the numbers several times. The whole SLS/Orion program (including things like hab modules and landers) is going to have lower costs than the shuttle program.

Considering there are no designs yet for hab modules and landers, estimates have to be qualified.  And considering that the current human rated vehicle NASA is building (i.e. Orion MPCV) is costing $8B or more, and taking 18 years until it becomes operational, I'd guess your estimates are probably a little low.

Now if NASA uses existing ISS modules, then great, not much development needed.  But no real need for the SLS either, since lower cost commercial launchers can deliver them too.  The best use of the SLS will be for SLS-sized payloads only, or like as you pointed out, those few robotic probes that could use an extra boost.

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NASA was able to run shuttle concurrently with the construction and maintenance of ISS. Increases to the budget don't have to be extreme.

A number of things to remember:

The ISS has a lot of partners.  NASA's portion of the station from 1985 to 2015 is estimated to be $72.4 billion in 2010 dollars, and the Shuttle provided 27 deliveries.  Taking into account the $1.2B average cost of the Shuttle (development not included), the Shuttle was almost half the cost of building the ISS.

Also, NASA's budget today is projected to be about $18B (in 2014 Constant Dollars).  NASA's budget during the ISS construction was up to a 1/3 more per year at it's peak.  You can't expect the same level of activity for the SLS at a far less vigorous budget level, especially one that doesn't even open up until the mid 2020's - well beyond when NASA needs to be flying the SLS every year for safety reasons.  The numbers don't add up.
Title: Re: SLS General Discussion Thread 2
Post by: notsorandom on 09/14/2015 02:23 PM
The cost of a launch system depends on who is doing the accounting. People in favor of a particular system tend to look at operational and marginal costs. Those opposed tend to throw in the cost of the development and what ever else. Thus it should be no surprise that the costs of a Shuttle mission has been quoted as from a few million to a billion dollars. SLS is no different.

The cost of flying one more Shuttle mission was quoted by Mike Griffin as about $300 million. That assumes that the operational costs for the year have been paid and there is extra production capacity. Griffin may have been low-balling a bit but it seems reasonable. There were 4 flights in 2008 and  5 flights in 2009 for about $3 billion per year. So with people estimating $500 million for SLS that sounds reasonable. SLS however is not able to be produced in huge numbers. The Shuttle could fly 5+ missions a year. SLS will be able to do 3 max a year with the current infrastructure.

The cost of the Delta IV Heavy is likely to be lower than people quote. EFT-1 cost $370 million not including the capsule but including the custom hardware such as the LES and boilerplate service module. That was a Delta IV procured commercially by the Orion program. While the pricing information is proprietary I'd bet that the cost is closer to $300 million than $400 million.
Title: Re: SLS General Discussion Thread 2
Post by: Coastal Ron on 09/14/2015 03:12 PM
The cost of a launch system depends on who is doing the accounting. People in favor of a particular system tend to look at operational and marginal costs. Those opposed tend to throw in the cost of the development and what ever else. Thus it should be no surprise that the costs of a Shuttle mission has been quoted as from a few million to a billion dollars. SLS is no different.

I look at the total cost, while also breaking out the development and operational portions.  It's the only way to get a full up apples-to-apples cost, since "marginal cost" estimates are usually simplified too far and ignore large classes of costs like overhead.

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The cost of flying one more Shuttle mission was quoted by Mike Griffin as about $300 million. That assumes that the operational costs for the year have been paid and there is extra production capacity.

Mike Griffin said a lot of things that were flat out wrong, and why make assumptions when facts exist?

There are a number of articles that look at total cost of the Shuttle program, and dividing the number of flights flown yields the average total cost - which was about $1.5B.  Some articles on the subject here:

As Shuttle Program Ends, Final Price Tag Is Elusive (http://www.wsj.com/articles/SB10001424052702303544604576433830373220742) - WSJ
5 Horrifying Facts You Didn't Know About the Space Shuttle (http://www.forbes.com/sites/carolpinchefsky/2012/04/18/5-horrifying-facts-you-didnt-know-about-the-space-shuttle/) - Forbes
NASA's Shuttle Program Cost $209 Billion (http://www.space.com/12166-space-shuttle-program-cost-promises-209-billion.html) — Was it Worth It? - Space.com

It's worth noting that NASA agrees with these numbers now.

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SLS will be able to do 3 max a year with the current infrastructure.

There is an NSF thread where this is discussed.  Bottom line is that as currently set up NASA can build slightly less than two per year, but with some additional money that can be increased to two per year.  Lots more money would be needed to increase that rate beyond two.

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The cost of the Delta IV Heavy is likely to be lower than people quote. EFT-1 cost $370 million not including the capsule but including the custom hardware such as the LES and boilerplate service module. That was a Delta IV procured commercially by the Orion program. While the pricing information is proprietary I'd bet that the cost is closer to $300 million than $400 million.

A number of years ago I was told (i.e. corrected) by Dr. Paul Spudis that a Delta IV Heavy cost $400M to NASA.  He and I didn't see eye to eye on commercial launch costs in general (he is an SLS fan), but I believed him on that.

Regardless though, thinking that the SLS will cost approximately the same as a Delta IV Heavy (i.e. $300-400M range) doesn't seem to make sense.  Delta IV Heavy is far more simple to manufacture, and it looks to be half the mass of the SLS.

If you want to look at what SLS costs were estimated to be, here is one article to look at.  Maybe it's very early in it's estimates, but that would provide a starting point for making corrections:

The HLV Cost Information NASA Decided Not To Give To Congress (http://nasawatch.com/archives/2011/01/the-hlv-cost-in.html) - NASA Watch

Some things cost what they cost, and they are worth what they cost to the users.  The Shuttle was that way, since Congress pretty much didn't care what the cost of each flight was - no one in Congress tracked it.  And if we had unlimited funding the cost of the SLS wouldn't really matter much either, but when budgets are constrained it does become an important factor, especially when the cost of the SLS is not just the rocket, but the payloads and missions that are built specifically for it.  You have to look at the opportunity cost.
Title: Re: SLS General Discussion Thread 2
Post by: TrevorMonty on 09/14/2015 03:50 PM
While a commercial LV eg FH probably could deliver DSH modules if they are based on ISS sized modules. The SLS can deliver these modules for free as they can go with the Orion on a crew flight to lunar space.
Title: Re: SLS General Discussion Thread 2
Post by: notsorandom on 09/14/2015 05:17 PM
The cost of a launch system depends on who is doing the accounting. People in favor of a particular system tend to look at operational and marginal costs. Those opposed tend to throw in the cost of the development and what ever else. Thus it should be no surprise that the costs of a Shuttle mission has been quoted as from a few million to a billion dollars. SLS is no different.

I look at the total cost, while also breaking out the development and operational portions.  It's the only way to get a full up apples-to-apples cost, since "marginal cost" estimates are usually simplified too far and ignore large classes of costs like overhead.
Well that is kinda my point. You are not in favor of SLS so you chose the method which gives the highest per flight cost. The original poster asked a very specific question of what the marginal cost was. That is a useful thing to ask. Once again we can used the Shuttle program as an example. There was debate about adding that final resupply mission. Going by your accounting method STS-135 cost $1.5 billion dollars. The extra money which needed to be added to the budget was nowhere near that. Marginal cost is a necessary thing to look at when planning out a manifest.

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The cost of flying one more Shuttle mission was quoted by Mike Griffin as about $300 million. That assumes that the operational costs for the year have been paid and there is extra production capacity.

Mike Griffin said a lot of things that were flat out wrong, and why make assumptions when facts exist?

There are a number of articles that look at total cost of the Shuttle program, and dividing the number of flights flown yields the average total cost - which was about $1.5B.  Some articles on the subject here:

As Shuttle Program Ends, Final Price Tag Is Elusive (http://www.wsj.com/articles/SB10001424052702303544604576433830373220742) - WSJ
5 Horrifying Facts You Didn't Know About the Space Shuttle (http://www.forbes.com/sites/carolpinchefsky/2012/04/18/5-horrifying-facts-you-didnt-know-about-the-space-shuttle/) - Forbes
NASA's Shuttle Program Cost $209 Billion (http://www.space.com/12166-space-shuttle-program-cost-promises-209-billion.html) — Was it Worth It? - Space.com

It's worth noting that NASA agrees with these numbers now.
Those articles do not give the marginal cost, only total cost. The facts you are providing do not answer the question. Griffin, like him or hate him, was the administrator of NASA and is an authoritative source. He was asked what the marginal cost was. His answer is in line with the program budgetary figure from that time. If the the cost to fly an extra Shuttle mission was $1.5 billion how did they budget ~$3 billion in 2009 and fly 5 missions?
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SLS will be able to do 3 max a year with the current infrastructure.

There is an NSF thread where this is discussed.  Bottom line is that as currently set up NASA can build slightly less than two per year, but with some additional money that can be increased to two per year.  Lots more money would be needed to increase that rate beyond two.


The current infrastructure can support up to 3 launches a year and produce two rockets a year. That figure comes straight from the SLS program.
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The cost of the Delta IV Heavy is likely to be lower than people quote. EFT-1 cost $370 million not including the capsule but including the custom hardware such as the LES and boilerplate service module. That was a Delta IV procured commercially by the Orion program. While the pricing information is proprietary I'd bet that the cost is closer to $300 million than $400 million.

A number of years ago I was told (i.e. corrected) by Dr. Paul Spudis that a Delta IV Heavy cost $400M to NASA.  He and I didn't see eye to eye on commercial launch costs in general (he is an SLS fan), but I believed him on that.
Did ULA give LM and the Orion program a $100 million discount on the price of a Delta IV heavy? Its an expensive rocket but its not $400 million, at least to launch a NASA payload like Orion.
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Regardless though, thinking that the SLS will cost approximately the same as a Delta IV Heavy (i.e. $300-400M range) doesn't seem to make sense.  Delta IV Heavy is far more simple to manufacture, and it looks to be half the mass of the SLS.

If you want to look at what SLS costs were estimated to be, here is one article to look at.  Maybe it's very early in it's estimates, but that would provide a starting point for making corrections:

The HLV Cost Information NASA Decided Not To Give To Congress (http://nasawatch.com/archives/2011/01/the-hlv-cost-in.html) - NASA Watch
Still not talking about marginal costs here. Also using 4 year old data on a hypothetical program rather than data from a program which is bending metal now. This also highlights the problem with your favored accounting method. It only works on finished programs which are no longer flying, or if one can predict the future number of flights. Here it is an arbitrary 18 flights. BTW the Direct guys made a pretty good argument that sidemount would have cost more. That chart was talked a lot about back when it was first posted.

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Some things cost what they cost, and they are worth what they cost to the users.  The Shuttle was that way, since Congress pretty much didn't care what the cost of each flight was - no one in Congress tracked it.  And if we had unlimited funding the cost of the SLS wouldn't really matter much either, but when budgets are constrained it does become an important factor, especially when the cost of the SLS is not just the rocket, but the payloads and missions that are built specifically for it.  You have to look at the opportunity cost.
There is a fallacy in your argument. By talking about alternatives to SLS and opportunity cost you are begging the question of if those other options would enjoy the same funding and political support. Based on recent history that is certainly not a given. But that all is space policy and this isn't the place for that.
Title: Re: SLS General Discussion Thread 2
Post by: Coastal Ron on 09/14/2015 07:40 PM
The SLS can deliver these modules for free as they can go with the Orion on a crew flight to lunar space.

Nothing is "free".  The cost of the launch would just be spread across all of the payload customers onboard, which in this case might be different departments within NASA, but NASA is still paying the full up cost.  Fully loading a launch vehicle is a good idea, just that there is a cost associated with each item on that launch.
Title: Re: SLS General Discussion Thread 2
Post by: arachnitect on 09/14/2015 08:07 PM
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The cost of the Delta IV Heavy is likely to be lower than people quote. EFT-1 cost $370 million not including the capsule but including the custom hardware such as the LES and boilerplate service module. That was a Delta IV procured commercially by the Orion program. While the pricing information is proprietary I'd bet that the cost is closer to $300 million than $400 million.

A number of years ago I was told (i.e. corrected) by Dr. Paul Spudis that a Delta IV Heavy cost $400M to NASA.  He and I didn't see eye to eye on commercial launch costs in general (he is an SLS fan), but I believed him on that.
Did ULA give LM and the Orion program a $100 million discount on the price of a Delta IV heavy? Its an expensive rocket but its not $400 million, at least to launch a NASA payload like Orion.


Solar Probe Plus is $389 million. Who knows what D-IVH cost or availability will be later in the decade?

The equivalent Vulcan-ACES would be cheaper, but not available until the mid 2020's.
Title: Re: SLS General Discussion Thread 2
Post by: Coastal Ron on 09/14/2015 08:14 PM
Well that is kinda my point. You are not in favor of SLS so you chose the method which gives the highest per flight cost. The original poster asked a very specific question of what the marginal cost was. That is a useful thing to ask.

Here is the challenge.  When figuring out costs based on total spending, it's easy to see what the per unit cost is.  Total cost divided by the number of flights.  Simple math that everyone can understand.

Figuring out marginal cost though is not easy.  I've done a lot of digging to figure out marginal costs for the Shuttle program, and though I'm pretty good at it (I've done this for work purposes too), I was never able to use public records to figure it out.

Why?  Because once the Shuttle became a sustaining program the pieces and parts that make up a Shuttle, and the contracts that were issued for work to be performed, never lined up.  And even when they did, like when USA was formed to consolidate all Shuttle processing work, later amendments are either hard to find or hard to allocate to a specific Shuttle flight.

So the best that can be said is that whatever marginal costs are calculated using publicly available documentation, they will under-represent the actual marginal cost - potentially by quite a bit.

That can't happen when you're using total cost.

Now both total cost and marginal cost (where accurate) are useful for different reasons.  Total cost doesn't make a lot of sense when you haven't flown anything, but it does show what the opportunity costs are that you're giving up.  Marginal cost doesn't mean a lot if you don't remember how much it took to get to unit #1.

For instance, theoretically you could spend $1Trillion over 50 years to build a system that lifts 250mT but only costs $10M/launch.  However what was the opportunity cost for that?  How much could you have lifted with current commercial launch vehicles with that $1Trillion?  There are always tradeoffs...

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Once again we can used the Shuttle program as an example. There was debate about adding that final resupply mission. Going by your accounting method STS-135 cost $1.5 billion dollars. The extra money which needed to be added to the budget was nowhere near that. Marginal cost is a necessary thing to look at when planning out a manifest.

Like all hardware programs, there were pieces and parts laying around that were mismatched purchases, so sure, the last flight could have been added without writing a check for $1.5B.  But that's because the Shuttle program had over-bought, and there were pre-negoitated contracts that could be extended.  And using end-of-life costing for a program just starting out doesn't make sense.

Now take a look at the SLS program.  There are no firm designs yet, since there are no customers and there are multiple configurations.  So there is no possible way to accurately figure out "marginal cost" when you don't know what you are building and you are just starting to build your first unit.  Boeing certainly doesn't know what their costs will be for units #1, 2 and 3, and neither does NASA.

When I say no firm designs, I mean from a manufacturing standpoint.  My specialty is in being the person that receives a customer order and sets up the entire manufacturing schedule for delivering the customer what they ordered.  I've done this for government one-off products, and high volume commercial electronics, so I have a lot of experience.  And as of today there are no customer order-able configurations for the SLS - and there wouldn't be, since the SLS is likely to be customized for every launch for quite a while.  But what that means is figuring out "marginal cost" from outside the SLS Program Office is impossible, and even for them it will take a lot of work.
Title: Re: SLS General Discussion Thread 2
Post by: sdsds on 09/15/2015 08:47 AM
Solar Probe Plus is $389 million.

And even with a Delta 4-Heavy launch the mission will need seven flybys of Venus!?! Has anyone explored what SLS with an EUS could do to improve that? It's just a hypothetical... but an interesting one nonetheless.
Title: Re: SLS General Discussion Thread 2
Post by: notsorandom on 09/15/2015 01:59 PM
Well that is kinda my point. You are not in favor of SLS so you chose the method which gives the highest per flight cost. The original poster asked a very specific question of what the marginal cost was. That is a useful thing to ask.

Here is the challenge.  When figuring out costs based on total spending, it's easy to see what the per unit cost is.  Total cost divided by the number of flights.  Simple math that everyone can understand.
How many flights will there be? I don't have a crystal ball.
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Figuring out marginal cost though is not easy.  I've done a lot of digging to figure out marginal costs for the Shuttle program, and though I'm pretty good at it (I've done this for work purposes too), I was never able to use public records to figure it out.

Why?  Because once the Shuttle became a sustaining program the pieces and parts that make up a Shuttle, and the contracts that were issued for work to be performed, never lined up.  And even when they did, like when USA was formed to consolidate all Shuttle processing work, later amendments are either hard to find or hard to allocate to a specific Shuttle flight. So the best that can be said is that whatever marginal costs are calculated using publicly available documentation, they will under-represent the actual marginal cost - potentially by quite a bit. That can't happen when you're using total cost.
Its pretty easy. The marginal cost is what was needed to be added to the budgets beyond the yearly sustaining costs. The Shuttle didn't fly the same number of times every year. Thus they had to budget for each mission they flew. To bring this to SLS the question is if we fly one rocket this year how much more money will it take to fly another. That was the original question.

Diverting the discussion to total program cost is just confusing the issue. There is no way to calculate it because you need the program to have ended before you get the real figure. Some say SLS will only fly 4 times others that it will fly 40 or more. That is an order of magnitude! Each flight makes the per launch cost go down a little. So if using the ongoing total cost of missions flown to this point / costs till now to decide to continue the program of not you are using a metric which gives the most encouragement to cancel the program at the start. Wow EM-1 cost over $10 billion, we better not launch EM-2!
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Now both total cost and marginal cost (where accurate) are useful for different reasons.  Total cost doesn't make a lot of sense when you haven't flown anything, but it does show what the opportunity costs are that you're giving up.  Marginal cost doesn't mean a lot if you don't remember how much it took to get to unit #1.

For instance, theoretically you could spend $1Trillion over 50 years to build a system that lifts 250mT but only costs $10M/launch.  However what was the opportunity cost for that?  How much could you have lifted with current commercial launch vehicles with that $1Trillion?  There are always tradeoffs...
Opportunity costs are a great way of arguing against any ongoing program because you can attack it without having to to suggest anything better. You also don't have to really make any evaluation on what are the other realistic opportunities. The FY2011 option was not a valid opportunity for example because it had no political support. SLS while perhaps not being the best technical solution may be the best option for which an opportunity exists.
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Once again we can used the Shuttle program as an example. There was debate about adding that final resupply mission. Going by your accounting method STS-135 cost $1.5 billion dollars. The extra money which needed to be added to the budget was nowhere near that. Marginal cost is a necessary thing to look at when planning out a manifest.
Like all hardware programs, there were pieces and parts laying around that were mismatched purchases, so sure, the last flight could have been added without writing a check for $1.5B.  But that's because the Shuttle program had over-bought, and there were pre-negoitated contracts that could be extended.  And using end-of-life costing for a program just starting out doesn't make sense.

Now take a look at the SLS program.  There are no firm designs yet, since there are no customers and there are multiple configurations.  So there is no possible way to accurately figure out "marginal cost" when you don't know what you are building and you are just starting to build your first unit.  Boeing certainly doesn't know what their costs will be for units #1, 2 and 3, and neither does NASA.

When I say no firm designs, I mean from a manufacturing standpoint.  My specialty is in being the person that receives a customer order and sets up the entire manufacturing schedule for delivering the customer what they ordered.  I've done this for government one-off products, and high volume commercial electronics, so I have a lot of experience.  And as of today there are no customer order-able configurations for the SLS - and there wouldn't be, since the SLS is likely to be customized for every launch for quite a while.  But what that means is figuring out "marginal cost" from outside the SLS Program Office is impossible, and even for them it will take a lot of work.
Use any other STS flight that was the second of the year. Each one had to be budgeted. The question of what it takes to fly one more flight under this next year's budget is a question they had to answer almost every year when the program was flying. It is odd to think think that for 30 years the STS program had no clue what each mission would cost.

SLS passed CDR. To say there are no firm designs yet is wrong. SLS like most other rockets has different configurations. Each one of those configurations doesn't have to fly to figure out what things cost. The costing information is actually pretty well informed via STS experience.

You are undoubtedly good at what you do and knowledgeable about it. However it is not a given that the products you work with and your experience working with them are similar to large NASA HSF projects. If you are asking people to look at your resume and accept your arguments as an expert opinion then you are also inviting people to look at the opinions of other informed people. There are many that are more intimately knowledgeable with NASA's projects and practices both in the agency and other decision making organs of the government. The majority of those people disagree with you about SLS, some agree. It is an inconclusive way of approaching the issue at best.
Title: Re: SLS General Discussion Thread 2
Post by: Coastal Ron on 09/15/2015 05:13 PM
Its pretty easy. The marginal cost is what was needed to be added to the budgets beyond the yearly sustaining costs. The Shuttle didn't fly the same number of times every year. Thus they had to budget for each mission they flew.

No, that is not how the Shuttle program was funded, which goes to show why trying to estimate marginal costs is so fraught with potential for being underestimated.

For instance, the Shuttle External Tank (ET) and Solid Rocket Motors (SRM) were purchased in large multi-year contracts.  Sometimes those contracts were further amended, extending the contract periods too.  Here are two articles that show that:

NASA Extends Space Shuttle External Tank Contract (http://www.spaceref.com/news/viewpr.html?pid=24363) - SpaceRef
NASA Extends Reusable Solid Rocket Motor Contracts with ATK Thiokol Through May 2007 (http://www.spaceref.com/news/viewpr.html?pid=8785) - SpaceRef

Even the contract with USA was multi-year, which replaced a quite a few individual contracts that would have had overlapping periods of performance, as well as tasks:

United Space Alliance and NASA Sign Space Flight Operations Contract (http://www.thefreelibrary.com/United+Space+Alliance+and+NASA+Sign+Space+Flight+Operations+Contract-a018721721) - Free Online Library

Notice that all of these contracts extended beyond the budget horizon for NASA.  This is something I'm very familiar with, since if I was the scheduling manager for the Shuttle or SLS programs I would be involved with procurement and contracts in defining how far out into the future we would be making purchases for every type of component, from screws to SRM's.

Everything is dependent on volume - how many of something you plan to make.  And it's even more complicated than that, since you have to account for how many, when, and of what configuration.

The more uncertainty there is in quantity, time and configuration means less certainty in cost, since contracts can't be defined and finalized until there is some agreed upon level of certainty.  But when enough can be decided, then contracts are negotiated years in advance of an SLS flight, and years in advance of the approved NASA budget.  You can see that in all three of the articles I referenced above.

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To bring this to SLS the question is if we fly one rocket this year how much more money will it take to fly another. That was the original question.

What I've shown is that it's not easy to determine what the marginal costs are.  And until NASA gets approval to start building operational SLS, and those contracts get negotiated and made public, no one in the public will know what the real marginal costs will be.
Title: Re: SLS General Discussion Thread 2
Post by: notsorandom on 09/15/2015 07:10 PM
Even with multi-year contracts NASA still has to request a budget one year at a time. The number of manifested flights drove the yearly funding request of STS line item. It boils down to this, either NASA can answer the question of how much more money needs to be in the yearly budget request to launch a rocket or it cannot. It has been launching a rockets and requesting budgets for a while now. NASA is perfectly capable of figuring out the difference in cost between flying one SLS or two.
Title: Re: SLS General Discussion Thread 2
Post by: arachnitect on 09/15/2015 07:21 PM
Solar Probe Plus is $389 million.

And even with a Delta 4-Heavy launch the mission will need seven flybys of Venus!?! Has anyone explored what SLS with an EUS could do to improve that? It's just a hypothetical... but an interesting one nonetheless.

It has come up in SLS threads.

Boeing has a Solar Probe Plus successor in some of the marketing literature that gets even closer than SP+. I forget exactly which version of SLS it uses.
Title: Re: SLS General Discussion Thread 2
Post by: Coastal Ron on 09/15/2015 07:56 PM
Even with multi-year contracts NASA still has to request a budget one year at a time.

NASA provides a budget request for more than one year.  The current FY 2016 President's Budget Request Summary covers FY2016 thru 2020, so that is a five year plan.

However Congress may only approve a budget one year at a time.

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The number of manifested flights drove the yearly funding request of STS line item.

You may not have read the articles I linked, or understood the implications of them.  For instance, the External tank was being purchased in block buys that stretched over a 7-year period, meaning it was well beyond the budget planning horizon.

And the reason for that is cost, since buying ET's one at a time would have raised the price quite a bit, whereas doing a block buy results in big cost savings.  We don't know yet what NASA will be allowed to do once Congress authorizes NASA to start building production SLS.

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It boils down to this, either NASA can answer the question of how much more money needs to be in the yearly budget request to launch a rocket or it cannot. It has been launching a rockets and requesting budgets for a while now. NASA is perfectly capable of figuring out the difference in cost between flying one SLS or two.

NASA may know some point in the future, but that doesn't mean the public will know.  And so far NASA has not released any cost information about the SLS, and is very late in doing so.

So in regards to "marginal cost", when the initial development units have not been produced and tested, and NASA has no idea what the initial number of SLS will be that Congress will authorize for procurement, there is not enough valid information to use "marginal cost" to estimate how much a production SLS will cost.

Fascinating subject, for sure, but I'll leave it at that...
Title: Re: SLS General Discussion Thread 2
Post by: 93143 on 09/20/2015 06:23 AM
You seriously think the incremental cost of the SLS is only a few hundred million dollars?

Yes.  What amazes me is that so many people seem to assume it's much higher, despite the fact that this makes no sense at all in light of the cost structure of any other rocket.  The torrent of anti-SLS propaganda, grassroots or otherwise, has done its work well.

I agree with you wholeheartedly that most SLS cost estimates are ridiculously overestimated (I think $500 Million is a little too low though). I was trying to give Rocketman a range of realistically imaginable costs.

Actually, the total cost estimates are probably in the ballpark, as long as you correct for the fact that Orion is usually lumped in.  It's just that people tend to assume that a rocket that costs (for example) $4B to launch once every two years would cost $8B to launch twice in a year, and it is this assumption that needs heading off at the pass.

There's also the effect of the modernization and cost reduction measures, which is not yet known.

Moving from one launch per year to two launches per year will almost certainly increase the annual SLS program budget by less than $500M in modern dollars, probably less than $400M, possibly less than $300M.

And in the absence of real cost numbers (which NASA is very behind on providing) comparisons to existing systems are one way to help estimate costs.
why make assumptions when facts exist?

Right, so how about that ESD Integration document (http://www.spacepolicyonline.com/images/stories/SLS_budget_Integration_2011-08.pdf) I linked you?

Or this (http://forum.nasaspaceflight.com/index.php?topic=18752.msg622582#msg622582)?

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So assuming that the SLS will be the same cost as the Delta IV Heavy, or even possibly less, doesn't look right.

Apples to oranges comparison.  We're talking about the marginal cost of SLS exclusive of fixed program costs, not the total recurring cost.  And it should indeed be similar to or lower than the market price of a DIVH (let's not forget that Delta IV is pretty much the most expensive large launcher for its size in the world, significantly less cost-effective than Atlas V).

Like I said, this is only relevant if you're able to get an SLS at marginal cost but would have to pay the sticker price on a DIVH.  I have suggested the former arrangement for science missions; the latter arrangement is the reason they usually go with Atlas...

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And considering that the current human rated vehicle NASA is building (i.e. Orion MPCV) is costing $8B or more, and taking 18 years until it becomes operational, I'd guess your estimates are probably a little low.

Orion is only doing this badly because the design had to mature under the continually tightening constraints imposed by Ares I.  Oh yeah, and it got outright cancelled at one point, resulting in a staffing gap; I'm sure that left its mark...  The European service module isn't helping the schedule...

Are you familiar with the Xeus concept?  I doubt NASA's $10B estimate for Altair applies to it...

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Now if NASA uses existing ISS modules, then great, not much development needed.  But no real need for the SLS either, since lower cost commercial launchers can deliver them too.

Deliver them where?  This isn't about a bunch of free-floating space station modules in LEO; it's about exploring deep space.

I look at the total cost, while also breaking out the development and operational portions.  It's the only way to get a full up apples-to-apples cost, since "marginal cost" estimates are usually simplified too far

On the contrary.  It's you who's simplifying too far:

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and ignore large classes of costs like overhead.

The whole point of marginal cost is that fixed costs are excluded so you can tell what the effect of a change will be.  Your method doesn't allow that, and someone who doesn't understand the difference between fixed and variable cost will get the impression that adding a flight is obscenely expensive.

Figuring out marginal cost though is not easy.  I've done a lot of digging to figure out marginal costs for the Shuttle program, and though I'm pretty good at it (I've done this for work purposes too), I was never able to use public records to figure it out.

That's funny; I had no trouble (http://www.gao.gov/products/NSIAD-93-115)...

The marginal cost of a launch in the context of the '90s-era STS program was about $80M in modern dollars.

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Marginal cost doesn't mean a lot if you don't remember how much it took to get to unit #1.

Of course not, but who could forget that?  Except that the SLS bashers insist on including Orion's costs and then neglecting to point out that they've done so; hence the $30B figure to 2021 (it also includes all the KSC work, somewhat more justifiably).

Also, a clarification may be in order.  When I say marginal cost, I don't mean the cost to add a unit to a finite production run.  I mean the cost to add a launch in an ongoing program without a clearly-defined end date, assuming there's enough infrastructure headroom to allow it.  (Since launches are usually scheduled far in advance, I model this as a marginal increase in flight rate.)  Cancelling the program early would allow NASA to save fixed costs as well as marginal costs, since they wouldn't have to keep the program running as long, but I'm not considering that scenario.

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Like all hardware programs, there were pieces and parts laying around that were mismatched purchases, so sure, the last flight could have been added without writing a check for $1.5B.  But that's because the Shuttle program had over-bought, and there were pre-negoitated contracts that could be extended.  And using end-of-life costing for a program just starting out doesn't make sense.

Late in the STS program's life (but before the end-of-life drawdown started), it could do five launches per year for a little over $3B.  That's total recurring cost (not including SFS, but that wasn't specifically part of STS, which is why it's still around).  $650M per launch, give or take (or about $750M in modern dollars), and the marginal cost associated with adding or deleting flights without changing the program duration was far less than that.

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there is no possible way to accurately figure out "marginal cost"

It doesn't have to be figured out to the cent.  But it can be estimated a lot more accurately than you're trying to imply, at least when the duration of the fixed-cost expenditure is not part of the estimate.  It will not cost a billion dollars to add an SLS flight.
Title: Re: SLS General Discussion Thread 2
Post by: Jim on 09/20/2015 12:27 PM
There is no way SLS marginal costs are less than a Delta IV Heavy.  SLS has more engines, more structure, more people involved, More contracts, etc.  It will be closer to 1 billion than 500 million.
Title: Re: SLS General Discussion Thread 2
Post by: the_other_Doug on 09/20/2015 03:02 PM
Getting closer and closer to starting a "Why I Hate SLS" thread and telling everyone to put their unending negative comments about SLS there, so I can ignore it and actually get discussion and updates about the actual vehicle that is being built, and will fly, in the appropriately useful threads.

And I'm not kidding.
Title: Re: SLS General Discussion Thread 2
Post by: ncb1397 on 09/20/2015 03:02 PM
Here is my cost estimate

4 X SSME: 40 million each, 160 million.
2 X SS-SRB: 25 milion each, 50 million.
1 X RL10-B2: 20 milllion????

The total for propulsion systems is only 230 million. If propulsion is something like half or even most of the cost of a rocket like ULA seems to be claiming, then you can get an estimate for the hardware cost of about 500 million which seems to be in line with what NASA officials are claiming. Of course, accounting for inflation, this number will be higher in the 2020s. So, yeah, adding an SLS is probably a few hundred million more than contracting with ULA for a Delta Heavy(~400 million).
Title: Re: SLS General Discussion Thread 2
Post by: oldAtlas_Eguy on 09/20/2015 04:37 PM
Um.

The problem is this:
- If the production lines run at a efficient rate (3 LVs in 1.5 years) then the $500M value is probably close to reality.
- But if the production rate is 1 every 2 years then the unit costs can no longer take advantage of running the production lines efficiently at the lowest cost per unit rate causing the cost per unit to about double to nearly $1B per unit.
-  The key would for NASA to purchase SLS's in blocks of 3 to be launched in a period of 5 years. This allows the production to run at the cheaper per unit cost then the production line closes and stays dormant for the next 3.5 years until the next order. Savings would be as high as $2.5B!!!!!
- The next item is the standing army for facility and key personnel to maintain the capability to launch at such a slow rate and to  be able to reopen the production lines. This is the $800-900M per year fixed cost. This makes the per flight costs of 1 every 2 years to be $2.1B to as high as $2.8B.
- At the full production rate capability of 2 every year the per launch cost would be from $.9B to $1B or $3.6B to $4B every 2 years <$2B more for three more flights in the same period or additional budget required of $600M per flight!!!!

SLS can be run economically but only if congress allows it to do so. But at $1B for 100mt that is a high $10,000/kg vs the FH of about 1/4 that at $2,500/kg. Only justifiable if the payload will not fit or get to where it needs to go using an FH. For bulk or smaller multiple payloads it will be cheaper (much cheaper) to launch them on an FH, even if you launch them singly instead of 3 or 4 at a time.
Title: Re: SLS General Discussion Thread 2
Post by: MarcAlain on 09/20/2015 05:53 PM
Is a hydrogen second stage even necessarily a bad thing when you're using solids as your main thrust/first stage?

What would the performance benefits be if they used similar thrust RP1 engines on the main liquid/second stage?
Title: Re: SLS General Discussion Thread 2
Post by: 93143 on 09/20/2015 07:36 PM
You can't assess marginal costs by adding up component prices, because those prices change with flight rate due to economies of scale.  You have to assess total program cost for multiple scenarios and compare them.  Both ESD Integration and DIRECT have done this, and I have reported their results.

(Also, IIRC SRBs were $25M per segment pair, not per booster.  Again, that's purchase price, not marginal cost.)

You also can't just "turn off" the production line, because then you have to re-hire all your workers and retrain their rusty skills (and/or hire a lot of new people and train them from scratch, since most people don't just sit around waiting for the call for 3+ years) before you can do anything.  This also seems like a good way to never work the bugs out of your production line; the launch rate is supposed to be no less than 1 per year for a reason.

The efficiency of a high production rate is simply that you get a lot of work out of your existing facilities and personnel.  Lowering the rate doesn't increase the marginal cost of a unit very much; what it does is increase that unit's share of the fixed costs.

There is no way SLS marginal costs are less than a Delta IV Heavy.  SLS has more engines, more structure, more people involved, More contracts, etc.  It will be closer to 1 billion than 500 million.

Apples to oranges.  Unless you're trying to tell me that the Delta IV Heavy price is pure marginal cost, with all fixed costs including supplier fixed costs shoved off onto the DoD...

I suppose it's possible in principle that the marginal cost could be strongly affected by optimizing production for very low flight rates, if the changes were radical enough.  But SLS is being set up for two units per year at steady state; you can only take such a scenario so far before it becomes more expensive than just using the Shuttle infrastructure as it stood, and $1B marginal cost per launch is past that point.  I don't see this as a serious possibility, not at the scale you people are talking about.
Title: Re: SLS General Discussion Thread 2
Post by: TomH on 09/20/2015 08:47 PM
Is a hydrogen second stage even necessarily a bad thing when you're using solids as your main thrust/first stage?

What would the performance benefits be if they used similar thrust RP1 engines on the main liquid/second stage?

RP-1 is the best choice there is for a first stage due to its ISP-DENSITY. You need immense amounts of thrust to fight gravity losses. With RP-1, you don't have the greatest amount of energy per Kg, but you do get the greatest amount of energy per liter (volume).

On an upper stage, ISP is king. Of all chemical engines, Hydrogen has the greatest amount of energy per Kg. At the same time, H2 takes requires a huge amount of volume to contain the fuel.

This is why Hydrogen is not a great choice in general for a first stage. In spite of the high ISP, you need ungodly volume, and the tanks to contain that volume are heavy. RP-1 is dense and the tanks can be smaller, therefore you can have a lot more fuel in the tanks. RP-1 provides the immense amount of thrust to overcome both gravity losses as well as the immense mass inertia of the full sized launch vehicle. Once you are in space, Hydrogen becomes the ideal choice (for chemical propulsion) because you have so much more energy per Kg. There are low thrust/high energy alternatives (once you are beyond LEO), that are better than Hydrogen, but they are not chemical rockets. Ion thrust using SEP (solar electric propulsion) or NEP (nuclear electric propulsion) have much higher ISP. These engines only put out a small amount of thrust per second, but over time, the total thrust they put out is far more than an equal mass of chemical propulsion. You can't use such engines at lower than orbital velocity, because they can't come even close to offsetting the opposing accelerative force of gravity. Once you are in deep space however, they are the best choice.

RP-1 would have been far better for either an SLS first stage or for its boosters, and Hydrogen is the best choice for an upper stage. SpaceX uses RP-1 on both stages, but takes performance loss in exchange for cheaper operating costs. This thread, however, is not the appropriate place to discuss any of these issues. They, in fact, have already been discussed in extreme length (think hundreds of threads and tens of thousands of posts) in other NSF forums. If you want to ask more questions, it behooves you to find those other threads, read up so that you have the necessary background knowledge, then pose any questions there. If we continue this mis-vectored tangent here, the moderators WILL delete the posts as being off-topic.

PostScript: Search for RAC-1, RAC-2, RAC-3 design.
Title: Re: SLS General Discussion Thread 2
Post by: Coastal Ron on 09/20/2015 09:57 PM
You also can't just "turn off" the production line, because then you have to re-hire all your workers and retrain their rusty skills (and/or hire a lot of new people and train them from scratch, since most people don't just sit around waiting for the call for 3+ years) before you can do anything.

This is the conundrum for the SLS, and really any transportation system that doesn't have an existing customer base.

Regarding the production line, it can run as slow as needed without firing and re-hiring the workers.  But that is pretty wasteful, and the only way to get around it is to have a workforce that can trained on multiple production processes so that they can build the SLS components serially.  Not cheap though.

The other part of it though is the items that are purchased, since those factories have the same production challenges.  The SRM's for sure, and likely other significant items.  Those factories have to figure out how to build at less than full production rates, and that affects costs quite a bit.

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This also seems like a good way to never work the bugs out of your production line; the launch rate is supposed to be no less than 1 per year for a reason.

I know Gerstenmaier was quoted about launch cadence, and I think his quote was about the launch personnel, but to some degree it does apply to the whole production chain.

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The efficiency of a high production rate is simply that you get a lot of work out of your existing facilities and personnel.  Lowering the rate doesn't increase the marginal cost of a unit very much; what it does is increase that unit's share of the fixed costs.

Lowering the production rate can affect costs very much, and what we don't know is where the cost inflection point is for SLS production.  It may not be until it reaches something like 4-6 per year (~ Shuttle rate).  NASA is quite proud of how efficient the tooling is for the SLS, which is good for touch labor costs, but overhead and other sustaining costs are going to be significant at low production rates, both for Boeing and every other major contractor for SLS.

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There is no way SLS marginal costs are less than a Delta IV Heavy.  SLS has more engines, more structure, more people involved, More contracts, etc.  It will be closer to 1 billion than 500 million.

Apples to oranges.  Unless you're trying to tell me that the Delta IV Heavy price is pure marginal cost, with all fixed costs including supplier fixed costs shoved off onto the DoD...

What ULA has going for them is that they can shift personnel between different production lines, so lower Delta IV production rates don't affect marginal cost as much.  Plus they now have the Bulk Buy contract, so their procurement folks can get price breaks for buying large quantities, even though they are delivered at the same rate they've already been buying them.

It will be interesting to see what Congress allows NASA to buy in their first production lot - only buy what has missions approved, or buy based on the forecast of flying X/year, regardless if there is a payload funded yet.

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I suppose it's possible in principle that the marginal cost could be strongly affected by optimizing production for very low flight rates, if the changes were radical enough.

Because the SLS is unique, and because it's being built for NASA in NASA facilities as opposed to a Boeing factory that it could share overhead and workforce with, SLS costs are going to be very high at low rates.  Not much that can be done about that.

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But SLS is being set up for two units per year at steady state; you can only take such a scenario so far before it becomes more expensive than just using the Shuttle infrastructure as it stood, and $1B marginal cost per launch is past that point.  I don't see this as a serious possibility, not at the scale you people are talking about.

The Shuttle shouldn't enter into this, since it was not a comparable transportation system, despite sharing some design elements.

The key though is that no upsized transportation system should be built until the existing transportation has been maxed out, and the new system is going to provide increased capacity for a known customer demand.  That is not the SLS, and because of that it is a big gamble.  Time will tell...
Title: Re: SLS General Discussion Thread 2
Post by: Jim on 09/20/2015 10:01 PM
(Also, IIRC SRBs were $25M per segment pair, not per booster.  Again, that's purchase price, not marginal cost.)

That was the cost of the SRM's and not the SRB's.
Title: Re: SLS General Discussion Thread 2
Post by: Jim on 09/20/2015 10:05 PM

Apples to oranges.  Unless you're trying to tell me that the Delta IV Heavy price is pure marginal cost,

No, one for one.  An additional Delta IV Heavy price would be almost pure marginal cost.   Anyways, if it isn't, it still makes the case that it is way cheaper than SLS.
Title: Re: SLS General Discussion Thread 2
Post by: Coastal Ron on 09/21/2015 01:01 AM
(Also, IIRC SRBs were $25M per segment pair, not per booster.  Again, that's purchase price, not marginal cost.)

That was the cost of the SRM's and not the SRB's.

As a point of reference, on a contract that ended in 2007 for 70 Shuttle SRM's their average cost was $34.3M each, or $68.6M per set.  Here is an article that talks about that contract (http://www.spaceref.com/news/viewpr.html?pid=8785).

Two things to keep in mind about those cost though:

1.  The contract was a multi-year contract for 70 total SRM's, so they were able to leverage volume discounts and known work levels.

2.  This particular contract was able to leverage being a continuation of previous contracts, so the workforce was already in place and stable, the supply chain was mature, and costs were well known.

The SLS SRM's, which are 5-segment, and new designs, can only be more expensive, not less than, what the Shuttle program was paying.
Title: Re: SLS General Discussion Thread 2
Post by: sdsds on 09/21/2015 01:15 AM
So If SLS were flying dozens of times per year the incremental cost of one additional flight might not vary much, and thus there might be a useful value to call the "marginal cost." But I would expect the incremental cost of a second flight in a given year to be different than the incremental cost of a third flight in that same year.

Can anyone defend talk of a single "marginal cost" value given the actual anticipated flight rate?
Title: Re: SLS General Discussion Thread 2
Post by: MarcAlain on 09/21/2015 01:49 AM
So If SLS were flying dozens of times per year the incremental cost of one additional flight might not vary much, and thus there might be a useful value to call the "marginal cost." But I would expect the incremental cost of a second flight in a given year to be different than the incremental cost of a third flight in that same year.

Can anyone defend talk of a single "marginal cost" value given the actual anticipated flight rate?
]

Well, not dozens. They'd likely have to double or triple their manufacturing capacities. Michoud can turn out a max of 4 per year, right?
Title: Re: SLS General Discussion Thread 2
Post by: Brovane on 09/21/2015 01:51 AM

Apples to oranges.  Unless you're trying to tell me that the Delta IV Heavy price is pure marginal cost, with all fixed costs including supplier fixed costs shoved off onto the DoD...


We can determine fairly closely the marginal cost of a Delta-IV Heavy DOD launch from the 2014 block-buy since this block buy was pure marginal cost.  The Engineering, launch operations, and Infrastructure had already been paid for.  You had 36 cores purchased for $4.3 Billion, which equals about $120 Million a core so we can infer about $360 Million for the incremental cost of a Delta-IV Heavy.

So for the Delta-IV heavy you have 3xR-68A engines and a RL-10 engine. 

The SLS is 4xRS-25 engines, 2xSRB plus whatever engines are on the upper core.  There is no way that you are getting that hardware for less cost than the Delta-IV Heavy hardware.  A R-68A is less than 1/2 the price of a RS-25 engine.  NASA working with AJR might get that price down further but the RS-25 unit price is not going to get itself below the price of a RS-68A. 

Yes, all the fixed costs of the Delta-IV Heavy production are on the DOD under the current EELV contracts under FAR rules.  That is one of the price advantages when a different part of the US government procures a EELV launch vehicle.  Now that could change in the future but that is how it is currently setup.  With the FAR contracting rules that ULA operates under it has to open it's books to the US govt and justify the costs it is charging.  If certain fixed costs have already been meet by US Govt DOD contracts then ULA under law cannot double charge the US govt for those same fixed costs.
Title: Re: SLS General Discussion Thread 2
Post by: Coastal Ron on 09/21/2015 03:32 AM
Well, not dozens. They'd likely have to double or triple their manufacturing capacities. Michoud can turn out a max of 4 per year, right?

NASA has currently set up the production rate to support building slightly less than two per year, and with some additional funding they can get up to two per year.
Title: Re: SLS General Discussion Thread 2
Post by: MarcAlain on 09/21/2015 04:35 AM
Well, not dozens. They'd likely have to double or triple their manufacturing capacities. Michoud can turn out a max of 4 per year, right?

NASA has currently set up the production rate to support building slightly less than two per year, and with some additional funding they can get up to two per year.

I'd be really happy if we got two launches per year.
Title: Re: SLS General Discussion Thread 2
Post by: Oli on 09/21/2015 08:08 AM
Is a hydrogen second stage even necessarily a bad thing when you're using solids as your main thrust/first stage?

What would the performance benefits be if they used similar thrust RP1 engines on the main liquid/second stage?

RP-1 is the best choice there is for a first stage due to its ISP-DENSITY.

RP-1 would have been far better for either an SLS first stage or for its boosters, and Hydrogen is the best choice for an upper stage.

- The impulse density of solid rockets is almost twice that of rp-1. Its also fairly easy to create lots of thrust with them.

- You could argue the SLS first stage a ground-lit upper stage.

We can determine fairly closely the marginal cost of a Delta-IV Heavy DOD launch from the 2014 block-buy since this block buy was pure marginal cost.  The Engineering, launch operations, and Infrastructure had already been paid for.  You had 36 cores purchased for $4.3 Billion, which equals about $120 Million a core so we can infer about $360 Million for the incremental cost of a Delta-IV Heavy.

To my knowledge the AF buys launches, not cores.


Apples to oranges.  Unless you're trying to tell me that the Delta IV Heavy price is pure marginal cost,

No, one for one.  An additional Delta IV Heavy price would be almost pure marginal cost.   Anyways, if it isn't, it still makes the case that it is way cheaper than SLS.

Well we don't know the price of an "additional" D4H, do we?
Title: Re: SLS General Discussion Thread 2
Post by: Chris Bergin on 09/21/2015 02:24 PM
Stay on topic guys. It gets really boring really fast when people start comparing SLS to Delta IV.
Title: Re: SLS General Discussion Thread 2
Post by: Brovane on 09/21/2015 05:59 PM
Stay on topic guys. It gets really boring really fast when people start comparing SLS to Delta IV.

The Delta-IV is the closest rocket we have to the SLS to compare cost. 
Title: Re: SLS General Discussion Thread 2
Post by: Brovane on 09/21/2015 06:03 PM

We can determine fairly closely the marginal cost of a Delta-IV Heavy DOD launch from the 2014 block-buy since this block buy was pure marginal cost.  The Engineering, launch operations, and Infrastructure had already been paid for.  You had 36 cores purchased for $4.3 Billion, which equals about $120 Million a core so we can infer about $360 Million for the incremental cost of a Delta-IV Heavy.

To my knowledge the AF buys launches, not cores.


That wording of "cores" is directly lifted from the Air Force press desk. 
Title: Re: SLS General Discussion Thread 2
Post by: sdsds on 09/21/2015 07:28 PM
NASA has currently set up the production rate to support building slightly less than two per year, and with some additional funding they can get up to two per year.

I think that's the interesting "marginal cost" to look at. Assume the anticipated rate is "three every two years." What is the incremental cost to reach "four every two years?" I think this is similar to what oldAtlas_Eguy attempts to estimate, with the result of $600M.

At the full production rate capability of 2 every year the per launch cost would be from $.9B to $1B or $3.6B to $4B every 2 years <$2B more for three more flights in the same period or additional budget required of $600M per flight!!!!

I personally believe it might be less than that, and by establishing a more natural cadence of operations might decrease the total likelihood of a LOM/LOC event. And the "cost" of just one of those would be enormous!
Title: Re: SLS General Discussion Thread 2
Post by: Coastal Ron on 09/21/2015 08:59 PM
NASA has currently set up the production rate to support building slightly less than two per year, and with some additional funding they can get up to two per year.

I think that's the interesting "marginal cost" to look at. Assume the anticipated rate is "three every two years." What is the incremental cost to reach "four every two years?" I think this is similar to what oldAtlas_Eguy attempts to estimate, with the result of $600M.

What is missing in all these "marginal cost" estimates is the biggest factor - real cost data.  Without that it's impossible to understand what the effects are of increasing or decreasing production rates.  That's why comparisons of other launch systems, such as the Shuttle and Delta IV Heavy, are really the closest we can get today.
Title: Re: SLS General Discussion Thread 2
Post by: 93143 on 09/22/2015 01:49 AM
what the effects are of increasing or decreasing production rates.

This.

You guys aren't getting this.  You can't calculate marginal cost from expenditure breakouts.

It isn't just the primary contractor that has fixed costs and variable costs.  Every subcontractor and part supplier does too.  And if you're a substantial fraction of someone else's business, your purchase rate will strongly affect their economies of scale, changing the price of the item(s).

So the only real way to get marginal cost is to figure out how the cost/price of everything you need changes with flight rate and compare the total program costs between different scenarios.  If you do this, you will get much lower numbers than anything you could calculate directly from your actual budget.

Please note that with the EELV program, it isn't that non-DoD customers are charged incremental cost, however that's calculated.  They're charged normally, and the DoD is reimbursed for the fixed cost thus defrayed.  And apparently (http://www.appropriations.senate.gov/sites/default/files/hearings/FINAL_SPACE_LAUNCH_BRIEFING.PDF) the amount of the reimbursement has been controversial in the past; the DoD was still complaining even after it tripled...

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Can anyone defend talk of a single "marginal cost" value given the actual anticipated flight rate?

Sorta, yeah.  See the previously-linked chart (http://forum.nasaspaceflight.com/index.php?topic=18752.msg622582#msg622582) from DIRECT for J-246.  Goes all the way from one flight per year to 16.  They did a bunch of these, plotting program cost or launch cost or cost per kilogram vs. flight rate for a variety of LVs.  Total costs tend to be largely fixed costs until the flight rate gets high enough, at which point variable costs (basically the stack of marginal costs on top of the fixed cost) start to dominate.  If extra infrastructure is required to go past a certain flight rate, there's a bump in the curve after that point due to the extra overhead (there'd be capital costs too, but those aren't recurring costs).

But marginal cost itself is not strongly dependent on flight rate, as long as you're within the infrastructure's capacity.  There's a bit of a learning curve, but the linked estimate shows a marginal cost of ~$320M in 2015 dollars to go from one flight per year to two, and ~$250M in 2015 dollars to go from seven flights per year to eight.

This particular contract was able to leverage being a continuation of previous contracts, so the workforce was already in place and stable, the supply chain was mature, and costs were well known.

The SLS SRM's, which are 5-segment, and new designs, can only be more expensive, not less than, what the Shuttle program was paying.

So now you're trying to lump DDT&E into the marginal cost?

The SLS boosters have been reworked for affordability.  If I recall correctly they slashed the required man-hours per segment by nearly 40%.  I'm not sure if they had to spend back some of that to solve the void issue, but it is not true that the boosters can only be more expensive in terms of either fixed or marginal cost, particularly if the manifest stabilizes and the supplier can plan ahead properly.

I would expect total prices to be higher per segment, since the flight rate is so low, but that's not marginal cost.

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The efficiency of a high production rate is simply that you get a lot of work out of your existing facilities and personnel.  Lowering the rate doesn't increase the marginal cost of a unit very much; what it does is increase that unit's share of the fixed costs.
Lowering the production rate can affect costs very much, and what we don't know is where the cost inflection point is for SLS production.  It may not be until it reaches something like 4-6 per year (~ Shuttle rate).  NASA is quite proud of how efficient the tooling is for the SLS, which is good for touch labor costs, but overhead and other sustaining costs are going to be significant at low production rates, both for Boeing and every other major contractor for SLS.

That is exactly what I just said, except that you're trying to conflate marginal and total recurring costs to make me look wrong.

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But SLS is being set up for two units per year at steady state; you can only take such a scenario so far before it becomes more expensive than just using the Shuttle infrastructure as it stood, and $1B marginal cost per launch is past that point.  I don't see this as a serious possibility, not at the scale you people are talking about.
The Shuttle shouldn't enter into this, since it was not a comparable transportation system, despite sharing some design elements.

You didn't read my links, did you?

The ESD Integration document contains multiple program cost estimates for an early version of SLS, based heavily on STS numbers where possible and CxP numbers where necessary.  Cases #3 and #4 finish development and set up a steady launch cadence, and Cases #4a and #4b are identical except that #4a contains an extra Block 1 launch per year (with Delta Heavy "kick stage"), which enables a direct comparison of annual budgets.  When I deflate the results using the inflation rates apparent in the data, the result is around $330M per year in modern dollars.  I think the Block 1 in question uses three main engines, so $350M is probably a better estimate for Block 1 as we know it.  Bump it up a bit for Block 1B, but don't just add parts costs because that will give you an overestimate - RL-10s are very cheap in terms of marginal cost, but AJR has to keep the doors open somehow.

The DIRECT chart I linked contains a plot of program cost vs. flight rate for a directly Shuttle-derived launch vehicle broadly comparable to SLS (J-246 = 2 cryo stages, 4xRS-25, 6xRL-10, 4-seg, unstretched core).  Just so you know (I don't imagine you're going to go look), it shows a baseline cost of just over $2B (maybe $2.06B, measuring on the image) for one launch per year, $2,348M at two per year, $2,866M at four per year, and so on up to $5,479M at 16 per year (this was before SpaceX took over 39A).  Those are 2009 dollars; multiplying by 1.123 to get 2015 dollars (NASA New Start 2014), it seems the estimate is about $320M to go from one flight per year to two.  SLS is a little bigger (more of a J-244SH (Stretched Heavy) than a J-246), so the numbers would probably be a little higher, all else being equal (all else is not equal because SLS is a modernized design without direct operational continuity).

SLS is a Shuttle-derived vehicle; it's not as directly derived as it might have been, but pretty much all the changes besides the core stretch and the extra booster segment are either directly or indirectly ops cost reductions.  As I said, it is possible that they could be trading higher marginal cost for lower fixed cost, but as I said the marginal cost can only go so high before this becomes counterproductive at the flight rate they're targeting.  Even with very low fixed costs, a marginal cost of $1B per flight (in addition to not passing the smell test) seems like it would be getting to the point where a more directly derived vehicle would have been cheaper to run at the targeted flight rate of two per year, so I don't consider that a reasonable possibility.

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The key though is that no upsized transportation system should be built until the existing transportation has been maxed out, and the new system is going to provide increased capacity for a known customer demand.

NASA is not a commercial launch provider, that has to respond to customer demands.  NASA is a space agency; one of its primary goals is to explore space, and it is currently planning to attempt manned deep space exploration.  To send people up there, NASA needs a hardware-moving capability that doesn't exist in the private sector.  There are a lot of options - depots, juiced-up versions of existing LVs, maybe SEP tugs for cargo shots - but they all cost billions in DDT&E that NASA has to ask the government for, and the option that the government seems to be willing to provide those billions for is SLS.
Title: Re: SLS General Discussion Thread 2
Post by: Coastal Ron on 09/22/2015 03:17 AM
You guys aren't getting this.  You can't calculate marginal cost from expenditure breakouts.

Being someone that has done cost rollups, actual numbers are better than generalized high level estimates.

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It isn't just the primary contractor that has fixed costs and variable costs.  Every subcontractor and part supplier does too.  And if you're a substantial fraction of someone else's business, your purchase rate will strongly affect their economies of scale, changing the price of the item(s).

I agree with that.  Which is why estimates that don't take into account flight rate, procurement lead time and buy quantities are prone to be inaccurate.  And we don't know any of those at this point.  NASA would have the best numbers, although they have not published them, but even so they don't know what Congress is going to allow them to procure on their first production buy.

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Please note that with the EELV program, it isn't that non-DoD customers are charged incremental cost, however that's calculated.  They're charged normally, and the DoD is reimbursed for the fixed cost thus defrayed.  And apparently (http://www.appropriations.senate.gov/sites/default/files/hearings/FINAL_SPACE_LAUNCH_BRIEFING.PDF) the amount of the reimbursement has been controversial in the past; the DoD was still complaining even after it tripled...

The ELC covers the launch infrastructure for USG payloads, and is a subsidy that is going away.  It was never part of the cost for the launch vehicle.

Now remember that ULA's pricing is very opaque according to the GAO, so we really don't know how they price Atlas V and Delta IV/H.  And commercial payloads would have different payload handling needs than Air Force payloads, so that cost would have to be known too.

But you and I have no idea whether ULA charges "incremental cost" or uses some other method.  We don't have insight into that, nor should we since they are a private company.

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Can anyone defend talk of a single "marginal cost" value given the actual anticipated flight rate?

Sorta, yeah.  See the previously-linked chart (http://forum.nasaspaceflight.com/index.php?topic=18752.msg622582#msg622582) from DIRECT for J-246.  Goes all the way from one flight per year to 16.

I can appreciate the detailed work the DIRECT folks did, but their assumptions were based on the continued use of the Shuttle supply chain.  The Shuttle supply chain ended, so the SLS can't leverage that, even for the SRM's.  Plus the SLS is a completely different design, which greatly affects projected costs.

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But marginal cost itself is not strongly dependent on flight rate.

Of course it is.  Maybe because I've been directly involved with defining production schedules and procurement buying decisions I understand this better than most.  There is a unique cost associated with every single part, and it is affected by your consumption rate (i.e. flight rate) and how much (and how often) you are buying for each part.  Those are major cost drivers for suppliers, as well as Boeing who is doing fabrication and final assembly.

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This particular contract was able to leverage being a continuation of previous contracts, so the workforce was already in place and stable, the supply chain was mature, and costs were well known.

The SLS SRM's, which are 5-segment, and new designs, can only be more expensive, not less than, what the Shuttle program was paying.

So now you're trying to lump DDT&E into the marginal cost?

My comment was related to the supply chain.  You do realize that suppliers won't keep worker sitting around twiddling their thumbs waiting for an SLS-related order to come in, right?  So they may have to train new workers or retrain prior workers on how to build SLS-related parts that are ordered infrequently.  That is added to the procurement price, since it a cost NASA has to bear, not the supplier.

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The SLS boosters have been reworked for affordability.  If I recall correctly they slashed the required man-hours per segment by nearly 40%.

Yes, finally after 135 flights ATK suddenly gets concerned about cost...

Look, if the SLS only flies once per year, then only 10 segments are needed per year.  And now that they are so much more efficient those same workers will be reassigned to work on something else for most of the year - or not, depending on whether their skills and work location allows that.  Those are pricing factors that are unknown at this point because we don't know what the flight rate is, and how many SLS NASA will be allowed to buy for, and what NASA will want for a delivery schedule.

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The key though is that no upsized transportation system should be built until the existing transportation has been maxed out, and the new system is going to provide increased capacity for a known customer demand.

NASA is not a commercial launch provider, that has to respond to customer demands.

NASA has no institutional skills for being a launch provider of any kind, and with the SLS they will have internal customers that they will have to respond to.  Which is why NASA should not be in the launch business.  The private sector, which was never asked, could have responded to any needs they had.
Title: Re: SLS General Discussion Thread 2
Post by: 93143 on 09/22/2015 04:25 AM
I can appreciate the detailed work the DIRECT folks did, but their assumptions were based on the continued use of the Shuttle supply chain.  The Shuttle supply chain ended, so the SLS can't leverage that, even for the SRM's.  Plus the SLS is a completely different design, which greatly affects projected costs.

Handwaving.  Am I supposed to assume that "greatly affects projected costs" means "triples the marginal cost of a launch"?

SLS is not a "completely different design".  It's an inline Shuttle-derived launch vehicle that's actually quite similar to Jupiter, but a little bigger, with modernizations and cost reductions.  You can't pretend Delta IV is a closer analogue than Jupiter.

Or didn't you notice that the marginal cost off the J-246 plot from 2009 is almost identical to the marginal cost I backed out of the ESD Integration SLS estimates from 2011?

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There is a unique cost associated with every single part, and it is affected by your consumption rate (i.e. flight rate) and how much (and how often) you are buying for each part.  Those are major cost drivers for suppliers, as well as Boeing who is doing fabrication and final assembly.

I just got through saying exactly that, except that I'm not trying to redefine "marginal cost" to mean "purchase price".  (Admittedly, I have had disagreements over terminology before, but it should be pretty obvious what I mean by this point.)

All that consumption rate dependency is due largely (not entirely, but in the main) to fixed cost; you buy less of something, or buy more sporadically, and the supplier's overhead becomes a bigger portion of the total, so the price per unit goes up.  This is a particularly strong effect if you're the sole customer for an item, since you have to eat the supplier's entire fixed cost regardless of how many you buy.  But it doesn't matter whose fixed cost it is; it's still fixed cost.

If you actually plot the total program cost vs. flight rate for a large launcher program with a reasonably well-defined launch schedule, the slope changes fairly slowly.  That slope is the marginal cost I'm talking about.
Title: Re: SLS General Discussion Thread 2
Post by: sdsds on 09/22/2015 05:37 AM
the marginal cost off the J-246 plot from 2009 is almost identical to the marginal cost I backed out of the ESD Integration SLS estimates from 2011

OK, that's impressive for sure.

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If you actually plot the total program cost vs. flight rate for a large launcher program with a reasonably well-defined launch schedule, the slope changes fairly slowly.  That slope is the marginal cost I'm talking about.

FWIW I'm kind of convinced.
Title: Re: SLS General Discussion Thread 2
Post by: Steven Pietrobon on 09/22/2015 06:20 AM
For what its worth, I crunched some numbers on SLS Block II costs using the NASA cost estimator. Per vehicle costs (not including development cost) with solid boosters was $680M to $810M and with liquid boosters it was $1.3B to $1.5B.

http://www.sworld.com.au/steven/pub/SLS-Moon-200715.pdf
Title: Re: SLS General Discussion Thread 2
Post by: spacenut on 09/22/2015 01:44 PM
What payload increase would the proposed liquid boosters give over solids?  Is the increase worth the cost increase? 
Title: Re: SLS General Discussion Thread 2
Post by: Brovane on 09/22/2015 07:37 PM

All that consumption rate dependency is due largely (not entirely, but in the main) to fixed cost; you buy less of something, or buy more sporadically, and the supplier's overhead becomes a bigger portion of the total, so the price per unit goes up.  This is a particularly strong effect if you're the sole customer for an item, since you have to eat the supplier's entire fixed cost regardless of how many you buy.  But it doesn't matter whose fixed cost it is; it's still fixed cost.

If you actually plot the total program cost vs. flight rate for a large launcher program with a reasonably well-defined launch schedule, the slope changes fairly slowly.  That slope is the marginal cost I'm talking about.

I cannot argue with this point about fixed cost and marginal cost to increase the number of flights.  Based on what you are showing in your graphs, the Jupiter-246 showed a marginal cost of ~320 Million and you expect the SLS to be in the same range?  Since the SLS is also Shuttle derived hardware. 
Title: Re: SLS General Discussion Thread 2
Post by: Coastal Ron on 09/22/2015 08:00 PM
SLS is not a "completely different design".  It's an inline Shuttle-derived launch vehicle that's actually quite similar to Jupiter, but a little bigger, with modernizations and cost reductions.

In manufacturing it's pretty black and white.  Either something is the same, or it's different.

The SLS is not a stretched Shuttle ET.  Other than the diameter of the SLS 1st stage, the Shuttle ET and the SLS 1st stage are of different designs, which makes sense since they have completely different load paths (i.e. side mount vs top loading).  Even the SRM's are completely different.  Plus the Shuttle didn't have a 2nd stage, so that is all new.

I think you need to read up on what the manufacturing challenges are for the SLS to better appreciate how different the SLS is from the Shuttle.  Here is one article to read:

SLS takes on new buckling standards, drops Super Light alloy (http://www.nasaspaceflight.com/2013/02/sls-new-buckling-standards-drops-super-light-alloy/) | NASASpaceFlight.com

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You can't pretend Delta IV is a closer analogue than Jupiter.

We have real prices for Delta IV/H, we don't have any real prices for Jupiter.  I know you feel paper studies will yield perfect information, the reality is that they don't represent reality, and reality could be higher and it could be lower in cost.

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I just got through saying exactly that, except that I'm not trying to redefine "marginal cost" to mean "purchase price".

The cost of buying material is an important part of determining "marginal cost".  However as I've shown with the Shuttle program, determining "marginal cost" from public sources is not easy because of the various procurement decisions that are made based on lead times, lot quantities, risk, and many other factors that don't get articulated to the public.

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If you actually plot the total program cost vs. flight rate for a large launcher program with a reasonably well-defined launch schedule, the slope changes fairly slowly.  That slope is the marginal cost I'm talking about.

Just because they intercept doesn't mean they are accurate.  We'll have to wait until Congress allows NASA to buy SLS production material before we find out what the real prices are.  But until then, based on using common sense and rough orders of magnitude, the SLS is going to be significantly more expensive than a $400M Delta IV Heavy - there is no way it can be close to the same or less.
Title: Re: SLS General Discussion Thread 2
Post by: 93143 on 09/22/2015 08:22 PM
Based on what you are showing in your graphs, the Jupiter-246 showed a marginal cost of ~320 Million and you expect the SLS to be in the same range?  Since the SLS is also Shuttle derived hardware.

Basically, yeah.

The leaked ESD Integration document (http://www.spacepolicyonline.com/images/stories/SLS_budget_Integration_2011-08.pdf) from 2011 seems to back me up.  Cases #4a and #4b have a few years at the end where development is over and the launch rate is steady (and plainly continues well into the future); aside from the "In Space Elements Wedge", the only difference is that #4a has an extra "70-ton" SLS launch every year (this vehicle seems to include a Delta Heavy upper stage).  The cost difference, summing SLS and ground systems, is $414M in 2023, $426M in 2024, and $437M in 2025.

The inflation rate in NASA New Start 2010 (use in FY11) is 2.6% from 2012 to the end of the table, except for 2013 and 2017 in which it is 2.7%.  This matches nicely with the rate of inflation apparent in the ESD Integration data.  Using NASA New Start 2010 (use in FY11) to deflate to 2011 and NASA New Start 2014 (use in FY15) to inflate it back to 2015 results in a marginal cost in modern dollars of about $330M.

$330M is pretty darn close to $320M considering the differences between the two vehicle designs, and the fact that one is measured off a graph and inflated by six years, while the other is deflated by fourteen years and reinflated by four...

Considering how close the deflated fixed costs are to the DIRECT estimate, as well as the fact that the estimates are explicitly said to be based on STS and CxP, I suspect there wasn't much modernization or cost reduction in the numbers.  If this is true, the actual vehicle should end up less expensive overall on an ongoing basis, though not necessarily on a marginal basis.


@Coastal Ron:  I never said the SLS estimates were perfect, or that much (or indeed any) of the design was identical to anything in the old Shuttle stack.  But neither of those things needs to be true for estimates based on the old technology to be useful in getting a rough idea of what the new technology might cost.  Sure, it's possible for a rash of slight design changes to cause the cost of an item to skyrocket, but intelligent engineers don't do that, and intelligent project managers don't let the dumb engineers do it either.

The major tech changes are all cost-reduction measures.  They're not going to cause the marginal cost to triple.

As for the Delta IV comparison...  I don't see why I should have to respond further.
Title: Re: SLS General Discussion Thread 2
Post by: sdsds on 09/22/2015 08:24 PM
We'll have to wait until Congress allows NASA to buy SLS production material before we find out what the real prices are. 

Are you seriously suggesting the cost of aluminum is significant in the incremental cost of one more SLS flight?
Title: Re: SLS General Discussion Thread 2
Post by: Brovane on 09/22/2015 08:42 PM
Based on what you are showing in your graphs, the Jupiter-246 showed a marginal cost of ~320 Million and you expect the SLS to be in the same range?  Since the SLS is also Shuttle derived hardware.

Basically, yeah.

The leaked ESD Integration document (http://www.spacepolicyonline.com/images/stories/SLS_budget_Integration_2011-08.pdf) from 2011 seems to back me up.  Cases #4a and #4b have a few years at the end where development is over and the launch rate is steady (and plainly continues well into the future); aside from the "In Space Elements Wedge", the only difference is that #4a has an extra "70-ton" SLS launch every year.  The cost difference, summing SLS and ground systems, is $414M in 2023, $426M in 2024, and $437M in 2025.

The inflation rate in NASA New Start 2010 (use in FY11) is 2.6% from 2012 to the end of the table, except for 2013 and 2017 in which it is 2.7%.  This matches nicely with the rate of inflation apparent in the ESD Integration data.  Using NASA New Start 2010 (use in FY11) to deflate to 2011 and NASA New Start 2014 (use in FY15) to inflate it back to 2015 results in a difference of about $330M.

$330M is pretty darn close to $320M considering the differences between the two vehicle designs, and the fact that one is measured off a graph and inflated by six years, while the other is deflated by fourteen years and reinflated by four...

Considering how close the deflated fixed costs are to the DIRECT estimate, as well as the fact that the estimates are explicitly said to be based on STS and CxP, I suspect there wasn't much modernization or cost reduction in the numbers.  If this is true, the actual vehicle should end up less expensive overall on an ongoing basis, though not necessarily on a marginal basis.

I cannot argue with that reasoning.  The difference that I keep forgetting between the SLS and Delta-IV is that the majority of the hardware development cost was paid for by Boeing and they charge a margin to make back that development cost above the normal hardware cost.  Which is perfectly reasonable.  The major components of the SLS are being developed and paid for using government funds.  Even the factory from the main booster tank is government facility, the transport vehicles are government vehicles.  We will see what the actual costs are once the flight program starts.  However you have made a sound argument for a marginal cost of around ~$320 Million,  I stand corrected.     
Title: Re: SLS General Discussion Thread 2
Post by: 93143 on 09/22/2015 08:50 PM
Well, with design differences and tech changes and the optimization of production for a low flight rate, there's probably a good deal of wiggle room in that number.

Personally, I think a full-up Block 1B should have a marginal cost to go from one flight per year to two of somewhere between $300M and $400M.  Higher and lower are both possible.  But I would be very surprised if it got up near $1B; that seems downright unreasonable...
Title: Re: SLS General Discussion Thread 2
Post by: Brovane on 09/22/2015 08:54 PM
Well, with design differences and tech changes and the optimization of production for a low flight rate, there's probably a good deal of wiggle room in that number.

Personally, I think a full-up Block 1B should have a marginal cost to go from one flight per year to two of somewhere between $300M and $400M.  Higher and lower are both possible.  But I would be very surprised if it got up near $1B; that seems downright unreasonable...

Well what will happen is if the fixed costs are $2 Billion for 1-flight and 2-flights are $2.4 Billion then it will be reported that each launch costs $1.2 Billion.  Just like the B-2 Bomber is quoted as costing $2 Billion per plane when at the end of the Production run, the incremental cost of adding another air-frame to the production run was ~$500 Million.  A couple of months ago during one of the Assured Access to Space hearings, the subject of using SLS for DOD launches was brought up by one of the Committee members but the USAF shot it down fairly quickly.  However ULA has stated that after they retire the Delta-IV medium, keeping the production line open for just the Delta-IV Heavy would result in a "significant" increase in price.  Which based on the models you present, a SLS Block-1B would be very price competitive against a Delta-IV heavy.       

To bad NASA cannot due a multi-year procurement block-buy of the SLS-Block 1B.  I would suspect that this would save even more money per LV.  However that would also mean that actual missions are also funded for the SLS.  Instead Congress likes to keep a tight rein on the purse strings, year to year.   
Title: Re: SLS General Discussion Thread 2
Post by: 93143 on 09/22/2015 09:47 PM
Well what will happen is if the fixed costs are $2 Billion for 1-flight and 2-flights are $2.4 Billion then it will be reported that each launch costs $1.2 Billion.  Just like the B-2 Bomber is quoted as costing $2 Billion per plane when at the end of the Production run, the incremental cost of adding another air-frame to the production run was ~$500 Million.

That is exactly why I keep bringing up marginal cost.  I've seen people claim that "the SLS flight rate is so low because it costs $xB per flight"...  No, it only costs that much per flight because the flight rate is so low.

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ULA has stated that after they retire the Delta-IV medium, keeping the production line open for just the Delta-IV Heavy would result in a "significant" increase in price.  Which based on the models you present, a SLS Block-1B would be very price competitive against a Delta-IV heavy.

That would seem to depend on what "significant" means, and on how much the SLS program can reduce overhead/infrastructure costs with tech enhancements and right-sizing; even now we don't know what effect the affordability effort has had.  The unimproved Shuttle-based SLS fixed cost is pretty high, and at two flights per year it would dominate the launch cost.

I can kinda see the HEOMD being convinced to sell launches to the SMD for marginal cost, but doing the same for the DoD seems a bit of a stretch.  Maybe - back in the day Shuttle launches were sold to all comers for marginal cost, which was about 1/10 of total recurring cost...

Also keep in mind that unlike Jupiter, SLS is being set up for a manufacturing rate of two per year (launch can do up to three per year by accumulating hardware first).  Going beyond that will require additional infrastructure investments.  I mean, I really hope the outlook improves enough that it gets done, but if not it might be a hurdle...

...yes, I do expect a significant reduction in fixed cost.  Advanced infrastructure capable of a small fraction of the Shuttle production rate should cost a heck of a lot less than the legacy infrastructure would have...
...

(BTW from that quote it sounds like there are indeed fixed costs in EELV prices.)

Quote
To bad NASA cannot due a multi-year procurement block-buy of the SLS-Block 1B.  I would suspect that this would save even more money per LV.  However that would also mean that actual missions are also funded for the SLS.  Instead Congress likes to keep a tight rein on the purse strings, year to year.

The numbers I've been using assume a steady launch rate and thus, I presume, a fairly predictable multi-year procurement schedule.  You can actually see something like this happening in the ESD Integration document, as costs start to diverge between the cases in 2016 (for ground systems) and 2017 (for SLS proper) even though the first "extra" launch is in 2022.

On the other hand, SLS can't launch less often than once per year or more often (as matters stand) than twice per year on average, and if the thing survives long enough to get to that point I don't expect the manifest to be quite as ethereal as it is now.  I don't see any reason why they couldn't run it more or less like they ran Shuttle once it gets going.
Title: Re: SLS General Discussion Thread 2
Post by: Steven Pietrobon on 09/23/2015 08:32 AM
What payload increase would the proposed liquid boosters give over solids?  Is the increase worth the cost increase?

The solids had better performance since they needed to use a core with five or six RS-25E engines in order to get above 130 t. Detailed information below:

RSRMV/6xRS-25E Core/2xJ-2X LUS = 137.0 t
Dark Knights/5xRS-25E Core/2xJ-2X LUS = 144.1 t
2xF-1B Boosters/4xRS-25E Core/2xJ-2X LUS = 133.2 t
3xAJ1E6 Boosters/4xRS-25E Core/2xJ-2 LUS = 136.2 t
Title: Re: SLS General Discussion Thread 2
Post by: spacenut on 09/23/2015 01:19 PM
I see you have the Dark Knights with 5 RS25E core.  What would that size core do with the F1's or AJ1E6's or even 6 like the RSRMV version?
Title: Re: SLS General Discussion Thread 2
Post by: Brovane on 09/23/2015 05:53 PM
[


That would seem to depend on what "significant" means, and on how much the SLS program can reduce overhead/infrastructure costs with tech enhancements and right-sizing; even now we don't know what effect the affordability effort has had.  The unimproved Shuttle-based SLS fixed cost is pretty high, and at two flights per year it would dominate the launch cost.

I can kinda see the HEOMD being convinced to sell launches to the SMD for marginal cost, but doing the same for the DoD seems a bit of a stretch.  Maybe - back in the day Shuttle launches were sold to all comers for marginal cost, which was about 1/10 of total recurring cost...

Also keep in mind that unlike Jupiter, SLS is being set up for a manufacturing rate of two per year (launch can do up to three per year by accumulating hardware first).  Going beyond that will require additional infrastructure investments.  I mean, I really hope the outlook improves enough that it gets done, but if not it might be a hurdle...


...

(BTW from that quote it sounds like there are indeed fixed costs in EELV prices.)



On the other hand, SLS can't launch less often than once per year or more often (as matters stand) than twice per year on average, and if the thing survives long enough to get to that point I don't expect the manifest to be quite as ethereal as it is now.  I don't see any reason why they couldn't run it more or less like they ran Shuttle once it gets going.

With just keeping the Delta-IV Heavy in production, ULA has said that there would be considerable cost for each launch.  Usually it seems the USAF has only about 1-payload a year that requires the Delta-IV Heavy.  If ULA needs to maintain the Production Line and two launch facilities for one launch a year we could see fairly substantial fixed costs for just one launch.  I could imagine the pricing for a single launch a year going at $1 Billion for all that support structure.  As you have shown, the projected cost of a single SLS each year is about $2 Billion.  At that pricing using the SLS, since you have a smaller incremental cost would seem to be the best thing.  Even if you just accept that you might be launching a 20-ton Satellite on a vehicle capable of 70+ tons of performance.  For Polar Orbits I wonder if the SLS could perform a "dog-leg" maneuver from the Cape and just take the performance hit? 
Title: Re: SLS General Discussion Thread 2
Post by: pathfinder_01 on 09/23/2015 11:14 PM




With just keeping the Delta-IV Heavy in production, ULA has said that there would be considerable cost for each launch.  Usually it seems the USAF has only about 1-payload a year that requires the Delta-IV Heavy.  If ULA needs to maintain the Production Line and two launch facilities for one launch a year we could see fairly substantial fixed costs for just one launch.  I could imagine the pricing for a single launch a year going at $1 Billion for all that support structure.  As you have shown, the projected cost of a single SLS each year is about $2 Billion.  At that pricing using the SLS, since you have a smaller incremental cost would seem to be the best thing.  Even if you just accept that you might be launching a 20-ton Satellite on a vehicle capable of 70+ tons of performance.  For Polar Orbits I wonder if the SLS could perform a "dog-leg" maneuver from the Cape and just take the performance hit?

Not going to happen for many reasons. ULA is already consolidating products. Vulcan should be cheaper as well as FH. No payload that size could come online fast enough. NASA is forbidden from competing with the private sector. Polar orbits are usually done out of Vandenberg for reasons of safety.

The only missions SLS can have are manned missions that are impossible to do with commercial crew or cargo or government missions unable to use commercial launchers and one would have to wonder what extra costs and delays doing this would add.
Title: Re: SLS General Discussion Thread 2
Post by: Brovane on 09/24/2015 02:19 AM




With just keeping the Delta-IV Heavy in production, ULA has said that there would be considerable cost for each launch.  Usually it seems the USAF has only about 1-payload a year that requires the Delta-IV Heavy.  If ULA needs to maintain the Production Line and two launch facilities for one launch a year we could see fairly substantial fixed costs for just one launch.  I could imagine the pricing for a single launch a year going at $1 Billion for all that support structure.  As you have shown, the projected cost of a single SLS each year is about $2 Billion.  At that pricing using the SLS, since you have a smaller incremental cost would seem to be the best thing.  Even if you just accept that you might be launching a 20-ton Satellite on a vehicle capable of 70+ tons of performance.  For Polar Orbits I wonder if the SLS could perform a "dog-leg" maneuver from the Cape and just take the performance hit?

Not going to happen for many reasons. ULA is already consolidating products. Vulcan should be cheaper as well as FH. No payload that size could come online fast enough. NASA is forbidden from competing with the private sector. Polar orbits are usually done out of Vandenberg for reasons of safety.

The only missions SLS can have are manned missions that are impossible to do with commercial crew or cargo or government missions unable to use commercial launchers and one would have to wonder what extra costs and delays doing this would add.

NASA is not forbidden from competing with the private sector.  Where are you getting that idea from? 

Yes, Polar Orbits are done usually out of Vandenberg for reasons of safety.  However high inclination orbits have been done out of the Cape by using a "dog-leg" trajectory.  Satellite launches have occurred using this maneuver to launch satellites to a inclination of 101-degrees.  These maneuver results in a reduction of vehicle performance but the SLS flying a DOD satellite wouldn't be flying anywhere near its maximum capability.

You can also reference this article from August about adapting SLS to fly additional payloads - http://www.nasaspaceflight.com/2015/08/usa-adapt-sls-additional-payloads/ (http://www.nasaspaceflight.com/2015/08/usa-adapt-sls-additional-payloads/)
Title: Re: SLS General Discussion Thread 2
Post by: Jim on 09/24/2015 02:58 AM
1.  NASA is not forbidden from competing with the private sector.  Where are you getting that idea from? 

2.  However high inclination orbits have been done out of the Cape by using a "dog-leg" trajectory. y



1.  Yes, it is.   Commercial Space Act.

2.  Only on a couple of occasions, and it required a 3 stage Delta vs a two stage.  And it wasn't really a dog leg, it was plane change much like for GSO sats.
Title: Re: SLS General Discussion Thread 2
Post by: pathfinder_01 on 09/24/2015 04:54 AM


http://www.nasaspaceflight.com/2015/08/usa-adapt-sls-additional-payloads/ (http://www.nasaspaceflight.com/2015/08/usa-adapt-sls-additional-payloads/)

Yes they are building an payload adapter in case they want to carry something other than Orion, but that something is very debatable as just about nothing has been funded.  The short of the Commercial Space Act is that if any private launch provider can do the mission then NASA must use it. This is an reversal of pre-Challenger NASA policy and the problems attempting to use the shuttle as the sole launch vechile. This is what makes Orbital, Space X, and ULA possible and what got NASA out of the business of launching communication sats and many probes.

The Air force handed responsibility to launch over to it's contractors and private space was born. Those contractors eventually merged into ULA.  This is part of the reason why ULA has both Delta(Boeing) and Atlas(LM). The payload would have to be too large(or something) for either Vulcan or FH to carry in order for SLS to be viable.

Lifting an 20 ton payload could be done by either, it just might not be able to be lifted into as high an orbit but if it falls into the range they can lift it can be done. The military which has much more political pull than NASA has not pushed for higher payload capacities than currently offered and likely would choose FH or Vulcan if they ever needed an bigger payload.

Polar Orbits from Florida present safety issues and would never be done as an matter of course. (i.e. For some reason the payload couldn't go out of Vandenberg).
Title: Re: SLS General Discussion Thread 2
Post by: TrevorMonty on 09/24/2015 05:15 AM




http://www.nasaspaceflight.com/2015/08/usa-adapt-sls-additional-payloads/ (http://www.nasaspaceflight.com/2015/08/usa-adapt-sls-additional-payloads/)

Yes they are building an payload adapter in case they want to carry something other than Orion, but that something is very debatable as just about nothing has been funded.  The short of the Commercial Space Act is that if any private launch provider can do the mission then NASA must use it.

Would NASA have use Vulcan even though the payload may require distributed launch which would add a higher risk factor compared to SLS.
Title: Re: SLS General Discussion Thread 2
Post by: Coastal Ron on 09/24/2015 05:16 AM
That would seem to depend on what "significant" means, and on how much the SLS program can reduce overhead/infrastructure costs with tech enhancements and right-sizing

Reduce?  NASA is a government entity, not a commercial one, they don't know how to reduce costs on a new product.  As to "tech enhancements and right-sizing", where are you hearing this?  NASA would have to pay Boeing more to change their current setup, and they have already locked in their current capabilities.

Quote
...even now we don't know what effect the affordability effort has had.

You keep talking about this like there is some unseen effort to significantly reduce costs.  Unless you can point it out in statements NASA or Boeing has made, it's not there.  They have built the production processes, and their costs are locked in.  As a data point, in an article SpaceNews has with the outgoing SLS Program Manager (http://spacenews.com/an-interview-with-boeings-outgoing-sls-program-manager/) they state:

"Boeing has Michoud set up to stamp out enough stages for one SLS a year — two at most with the factory’s current manufacturing capabilities, and then only if NASA pours more money and personnel into the facility."

This is low-rate production, and it's highly unusual to make significant changes to the production processes after pre-production (SLS-1 & SLS-2), and if they do it's because of problems that they will have found.

Quote
...yes, I do expect a significant reduction in fixed cost.  Advanced infrastructure capable of a small fraction of the Shuttle production rate should cost a heck of a lot less than the legacy infrastructure would have...

I think you've been listening to the NASA PR machine too much.

First of all the Shuttle manufacturing system built their tooling for relatively high volume.  The SLS is a different manufacturing design with different manufacturing processes, and it has a much lower production volume.  Plus that 1st stage is HUGE - there are only so many ways to bend metal that big.

Costs are locked in for building two SLS per year, so it would have to go up quite a bit to merit a significant investment in cost reduction technologies.  Maybe being authorized for a Mars program will merit that size of an investment, but we'll have to wait for that to happen.
Title: Re: SLS General Discussion Thread 2
Post by: pathfinder_01 on 09/24/2015 05:45 AM





Would NASA have use Vulcan even though the payload may require distributed launch which would add a higher risk factor compared to SLS.

That I don't know. I do know that if Vulcan can demonstrate distributed launch on an mission, NASA will be in an tougher(but far from impossible) position to justify SLS over it. There could be reasons like Vulcan can't lift the Payload in one piece or issues of time. Basically the more and more capable the Private sector becomes the harder and harder it gets for an Government owned rocket to find an mission. ULA would have motive and reason to push an lawsuit if distributed launch was equally capable of doing it.
Title: Re: SLS General Discussion Thread 2
Post by: Steven Pietrobon on 09/24/2015 09:00 AM
I see you have the Dark Knights with 5 RS25E core.  What would that size core do with the F1's or AJ1E6's or even 6 like the RSRMV version?

I never simulated those versions as I was only interested in the minimum configuration that got over 130 t. Nevertheless, I would expect significant payload increases with a five or six engine core.
Title: Re: SLS General Discussion Thread 2
Post by: Brovane on 09/24/2015 11:22 AM


http://www.nasaspaceflight.com/2015/08/usa-adapt-sls-additional-payloads/ (http://www.nasaspaceflight.com/2015/08/usa-adapt-sls-additional-payloads/)

Yes they are building an payload adapter in case they want to carry something other than Orion, but that something is very debatable as just about nothing has been funded.  The short of the Commercial Space Act is that if any private launch provider can do the mission then NASA must use it. This is an reversal of pre-Challenger NASA policy and the problems attempting to use the shuttle as the sole launch vechile. This is what makes Orbital, Space X, and ULA possible and what got NASA out of the business of launching communication sats and many probes.

The Air force handed responsibility to launch over to it's contractors and private space was born. Those contractors eventually merged into ULA.  This is part of the reason why ULA has both Delta(Boeing) and Atlas(LM). The payload would have to be too large(or something) for either Vulcan or FH to carry in order for SLS to be viable.

Lifting an 20 ton payload could be done by either, it just might not be able to be lifted into as high an orbit but if it falls into the range they can lift it can be done. The military which has much more political pull than NASA has not pushed for higher payload capacities than currently offered and likely would choose FH or Vulcan if they ever needed an bigger payload.

Polar Orbits from Florida present safety issues and would never be done as an matter of course. (i.e. For some reason the payload couldn't go out of Vandenberg).

I understand about the Commercial Space Act.  What you are leaving out is the cost-effective part.  If the choice is procuring Delta-IV Heavy's at launch price's of over $1 Billion or procuring a SLS at a incremental price of less than $ 500 Million then the SLS could be chosen.  During Congressional testimony the subject of using the SLS to bridge any launch capability gaps has been brought up. 

Ok, what you are saying about the Commercial Space Act would imply that if a Commercial Entity develops a comparable vehicle to the SLS that is cost-effective then NASA would have to use it.  Is that true? 
Title: Re: SLS General Discussion Thread 2
Post by: Jim on 09/24/2015 12:54 PM
I understand about the Commercial Space Act.  What you are leaving out is the cost-effective part.  If the choice is procuring Delta-IV Heavy's at launch price's of over $1 Billion or procuring a SLS at a incremental price of less than $ 500 Million then the SLS could be chosen. 

DIV isn't going to be over 1 billion and SLS incremental is going to be more than $500 million.
Title: Re: SLS General Discussion Thread 2
Post by: Brovane on 09/24/2015 01:04 PM
I understand about the Commercial Space Act.  What you are leaving out is the cost-effective part.  If the choice is procuring Delta-IV Heavy's at launch price's of over $1 Billion or procuring a SLS at a incremental price of less than $ 500 Million then the SLS could be chosen. 

DIV isn't going to be over 1 billion and SLS incremental is going to be more than $500 million.

The point is Jim is that there is enough exceptions in the Commercial Space Act to allow the acquisition of Space Transportation Services from a government launch vehicle even if a commercial provider could provide those services.  This act wouldn't prohibit the launching of a DOD payload on the SLS. 

Quote
TITLE II--FEDERAL ACQUISITION OF SPACE TRANSPORTATION SERVICES

(a) In General.--Except as otherwise provided in this section, the Federal Government shall acquire space transportation services from United States commercial providers whenever such services are required in the course of its activities. To the maximum extent practicable, the Federal Government shall plan missions to accommodate the space transportation services capabilities of United States commercial providers.
(b) Exceptions.--The Federal Government shall not be required to acquire space transportation services under subsection (a) if, on a case-by-case basis, the Administrator or, in the case of a national security issue, the Secretary of the Air Force, determines that--
(1) a payload requires the unique capabilities of the Space Shuttle;
(2) cost effective space transportation services that meet specific mission requirements would not be reasonably available from United States commercial providers when required;
(3) the use of space transportation services from United States commercial providers poses an unacceptable risk of loss of a unique scientific opportunity;
(4) the use of space transportation services from United States commercial providers is inconsistent with national security objectives;
(5) the use of space transportation services from United States commercial providers is inconsistent with international agreements for international collaborative efforts relating to science and technology;
(6) it is more cost effective to transport a payload in conjunction with a test or demonstration of a space transportation vehicle owned by the Federal Government; or
(7) a payload can make use of the available cargo space on a Space Shuttle mission as a secondary payload, and such payload is consistent with the requirements of research, development, demonstration, scientific, commercial, and educational programs authorized by the Administrator. Nothing in this section shall prevent the Administrator from planning or negotiating agreements with foreign entities for the launch of Federal Government payloads for international collaborative efforts relating to science and technology.
(c) Delayed Effect.--Subsection (a) shall not apply to space transportation services and space transportation vehicles acquired or owned by the Federal Government before the date of the enactment of this Act, or with respect to which a contract for such acquisition or ownership has been entered into before such date.
(d) Historical Purposes.--This section shall not be construed to prohibit the Federal Government from acquiring, owning, or maintaining space transportation vehicles solely for historical display purposes.
Title: Re: SLS General Discussion Thread 2
Post by: woods170 on 09/24/2015 01:05 PM
I understand about the Commercial Space Act.  What you are leaving out is the cost-effective part.  If the choice is procuring Delta-IV Heavy's at launch price's of over $1 Billion or procuring a SLS at a incremental price of less than $ 500 Million then the SLS could be chosen. 

DIV isn't going to be over 1 billion and SLS incremental is going to be more than $500 million.
The latter is an assumption Jim. There will be no such thing as an incremental price for SLS if it never flies.
Title: Re: SLS General Discussion Thread 2
Post by: Jim on 09/24/2015 02:05 PM
This act wouldn't prohibit the launching of a DOD payload on the SLS. 

True, but the DOD would prohibit it.  They will never get in bed with NASA on a NASA launch vehicle.
Title: Re: SLS General Discussion Thread 2
Post by: Brovane on 09/24/2015 02:30 PM
This act wouldn't prohibit the launching of a DOD payload on the SLS. 

True, but the DOD would prohibit it.  They will never get in bed with NASA on a NASA launch vehicle.

Very true, the DOD would be less than thrilled.  However if Congress directed funding for the DOD to procure a National Security launch on the SLS, the DOD couldn't say No to Congress.  Especially if Congress perceives a need for a backup to the FH and the DIVH production line is shutdown for the switchover to the Vulcan LV. 
Title: Re: SLS General Discussion Thread 2
Post by: Jim on 09/24/2015 03:01 PM

Very true, the DOD would be less than thrilled.  However if Congress directed funding for the DOD to procure a National Security launch on the SLS, the DOD couldn't say No to Congress.  Especially if Congress perceives a need for a backup to the FH and the DIVH production line is shutdown for the switchover to the Vulcan LV. 

Nonsense.  Congress isn't going to do that since they wouldn't know why it would be needed in the first place.  DOD would drag their feet anyway.  DIVH doesn't have a backup now anyways, so why would it need a backup to a back up.  DIVH is not shutting down until Vulcan can handle the missions.
Title: Re: SLS General Discussion Thread 2
Post by: Kansan52 on 09/24/2015 03:44 PM
I hadn't seen this statement that Coastal Ron posted:

"As a data point, in an article SpaceNews has with the outgoing SLS Program Manager they state:

"Boeing has Michoud set up to stamp out enough stages for one SLS a year — two at most with the factory’s current manufacturing capabilities, and then only if NASA pours more money and personnel into the facility.""

I was under the impression that the current budget would produce almost 1 and a half flyable SLS vehicles a year. That statement says only 1 without a large increase in the budget.

So, under the current budget, only 1 per year?
Title: Re: SLS General Discussion Thread 2
Post by: Brovane on 09/24/2015 03:53 PM

Very true, the DOD would be less than thrilled.  However if Congress directed funding for the DOD to procure a National Security launch on the SLS, the DOD couldn't say No to Congress.  Especially if Congress perceives a need for a backup to the FH and the DIVH production line is shutdown for the switchover to the Vulcan LV. 

Nonsense.  Congress isn't going to do that since they wouldn't know why it would be needed in the first place.  DOD would drag their feet anyway.  DIVH doesn't have a backup now anyways, so why would it need a backup to a back up.  DIVH is not shutting down until Vulcan can handle the missions.

ULA has already stated that they will phase out all DIV launches by 2018 except for DIVH.  On average the DIVH has only averaged about one launch a year.  This would mean that all the year over year costs for the DIVH production line and launch facility costs will have be amortized by ULA for this single yearly, DIVH launch.  This will have a large impact on the DIVH launch cost's, which are already about $400 Million.  This is why I think launch costs for the DIVH could soar approaching $1Billion.  Of course this would mean the DIVH would in no way be competitive with the FH (Once the FH gets EELV certification).  If ULA cannot get launch contracts for the DIVH they are going to shutdown the production line, regardless of the status of the Vulcan.

In my opinion, Congress would be forced to either; pay money to ULA to keep launch capability for DIVH, accept that FH is the only vehicle that can meet the full range of DOD payloads until Vulcan is in service, or use the SLS as a backup to the FH for DOD launches until the Vulcan is online. 

Title: Re: SLS General Discussion Thread 2
Post by: oldAtlas_Eguy on 09/24/2015 04:34 PM

Very true, the DOD would be less than thrilled.  However if Congress directed funding for the DOD to procure a National Security launch on the SLS, the DOD couldn't say No to Congress.  Especially if Congress perceives a need for a backup to the FH and the DIVH production line is shutdown for the switchover to the Vulcan LV. 

Nonsense.  Congress isn't going to do that since they wouldn't know why it would be needed in the first place.  DOD would drag their feet anyway.  DIVH doesn't have a backup now anyways, so why would it need a backup to a back up.  DIVH is not shutting down until Vulcan can handle the missions.

ULA has already stated that they will phase out all DIV launches by 2018 except for DIVH.  On average the DIVH has only averaged about one launch a year.  This would mean that all the year over year costs for the DIVH production line and launch facility costs will have be amortized by ULA for this single yearly, DIVH launch.  This will have a large impact on the DIVH launch cost's, which are already about $400 Million.  This is why I think launch costs for the DIVH could soar approaching $1Billion.  Of course this would mean the DIVH would in no way be competitive with the FH (Once the FH gets EELV certification).  If ULA cannot get launch contracts for the DIVH they are going to shutdown the production line, regardless of the status of the Vulcan.

In my opinion, Congress would be forced to either; pay money to ULA to keep launch capability for DIVH, accept that FH is the only vehicle that can meet the full range of DOD payloads until Vulcan is in service, or use the SLS as a backup to the FH for DOD launches until the Vulcan is online.
We are getting sidetracked.

The DIVH will share initially the 5m tank production line with Vulcan thereby reducing both vehicles costs while they are both in the low quantity mode. Vulcan because its is in early developmental test and flights. Once it goes operational and the build rate increases, that would be a good time to discontinue (or slightly before) DIVH. Note this would happen 2 years in advance of Vulcan going operational.

Since the AF policy for having redundant LV's to launch payloads is a policy and not a requirement, having a backup to the DIVH or even the FH which could replace the DIVH's position in launching these very heavy 20mt ppayloads is not a requirement for the AF such that they would spend a lot of money for little gain.

It took >$150M to certify the F9. To certify the SLS for DOD payloads, although some shortcuts can be done since it has such a high level of oversight from NASA, will be definitely more costly than certifying the F9 because it is a very complex vehicle and will not have a standard configuration until after 2021. Yhis means that it could not even be considered for DOD use until after the second flight which could occur as late as 2023 by which time Vulcan with ACES will be flying.
Title: Re: SLS General Discussion Thread 2
Post by: Jim on 09/24/2015 04:39 PM
use the SLS as a backup to the FH for DOD launches until the Vulcan is online. 


Never will happen
Title: Re: SLS General Discussion Thread 2
Post by: Jim on 09/24/2015 04:40 PM

It took >$150M to certify the F9. To certify the SLS for DOD payloads,

There is no need for SLS certification.  It is a gov't vehicle and not a commercial one.
Title: Re: SLS General Discussion Thread 2
Post by: pathfinder_01 on 09/24/2015 05:53 PM


In my opinion, Congress would be forced to either; pay money to ULA to keep launch capability for DIVH, accept that FH is the only vehicle that can meet the full range of DOD payloads until Vulcan is in service, or use the SLS as a backup to the FH for DOD launches until the Vulcan is online.

Note quite. Vulcan is planned to be online in 2019(1 year after SLS). FH will compete with Atlas and Delta from about 2016-2018. Delta is phased out in 2018,which allows plenty of time for planning and transitioning. Vulcan is up by about 2020/2019. There is hardly any gap. FH isn't the only vehicle that can meet the the full range of payloads unless relations with the Russians get much worse. Atlas launches most payloads with Delta only handling the largest.

Congress can not be forced to do anything by AF policy. However ULA and Space X could sue if an payload that they could launch is put on SLS.  Those exceptions are for specific purposes.
Title: Re: SLS General Discussion Thread 2
Post by: Brovane on 09/24/2015 06:07 PM


In my opinion, Congress would be forced to either; pay money to ULA to keep launch capability for DIVH, accept that FH is the only vehicle that can meet the full range of DOD payloads until Vulcan is in service, or use the SLS as a backup to the FH for DOD launches until the Vulcan is online.

Note quite. Vulcan is planned to be online in 2019(1 year after SLS). FH will compete with Atlas and Delta from about 2016-2018. Delta is phased out in 2018,which allows plenty of time for planning and transitioning. Vulcan is up by about 2020/2019. There is hardly any gap. FH isn't the only vehicle that can meet the the full range of payloads unless relations with the Russians get much worse. Atlas launches most payloads with Delta only handling the largest.

Congress can not be forced to do anything by AF policy. However ULA and Space X could sue if an payload that they could launch is put on SLS.  Those exceptions are for specific purposes.

This assumes the Vulcan Development proceeds without any problems/delays.  ULA doesn't even have the  commitment from Boeing and LM for full funding for development of the Vulcan.  They are going quarter by quarter right now for funding. 

If you look closely at the Commercial Space Act. Item #4 would qualify.  Congress could decide that having the SLS as a backup to the FH until Vulcan is online is consistent with national security objectives.  SpaceX and ULA could sue but they would loose the lawsuit. 

Quote
4) the use of space transportation services from United States commercial providers is inconsistent with national security objectives;
Title: Re: SLS General Discussion Thread 2
Post by: pathfinder_01 on 09/24/2015 06:13 PM


In my opinion, Congress would be forced to either; pay money to ULA to keep launch capability for DIVH, accept that FH is the only vehicle that can meet the full range of DOD payloads until Vulcan is in service, or use the SLS as a backup to the FH for DOD launches until the Vulcan is online.

Note quite. Vulcan is planned to be online in 2019(1 year after SLS). FH will compete with Atlas and Delta from about 2016-2018. Delta is phased out in 2018,which allows plenty of time for planning and transitioning. Vulcan is up by about 2020/2019. There is hardly any gap. FH isn't the only vehicle that can meet the the full range of payloads unless relations with the Russians get much worse. Atlas launches most payloads with Delta only handling the largest.

Congress can not be forced to do anything by AF policy. However ULA and Space X could sue if an payload that they could launch is put on SLS.  Those exceptions are for specific purposes.

This assumes the Vulcan Development proceeds without any problems/delays.  ULA doesn't even have the  commitment from Boeing and LM for full funding for development of the Vulcan.  They are going quarter by quarter right now for funding. 

If you look closely at the Commercial Space Act. Item #4 would qualify.  Congress could decide that having the SLS as a backup to the FH until Vulcan is online is consistent with national security objectives.  SpaceX and ULA could sue but they would loose the lawsuit. 

Quote
4) the use of space transportation services from United States commercial providers is inconsistent with national security objectives;

Delta Heavy won't go offline until Vulcan is online, so won't apply and Congress would be getting into to same mess it did back in the 80ies with respect to the Shuttle. Taking payloads away from the private sector is not an wise move for either the exploration of space or national security.  There is no need to use SLS as back up to Vulcan or FH. The smarter, cheaper and less politically dangerous move would just be to wait until Vulcan is online.
Title: Re: SLS General Discussion Thread 2
Post by: Jim on 09/24/2015 06:31 PM

If you look closely at the Commercial Space Act. Item #4 would qualify.  Congress could decide that having the SLS as a backup to the FH until Vulcan is online is consistent with national security objectives.  SpaceX and ULA could sue but they would loose the lawsuit. 


Congress isn't going to make that choice, it would be up the DOD and as stated before, they would not do it.

SLS doesn't have a VAFB launch capability and what was done with a few Delta flights in the 60's/70's out of the east coast is not applicable. The spacecraft are too large.   The DOD also requires payload installation and access at the pad, which SLS can not support. 
Title: Re: SLS General Discussion Thread 2
Post by: psloss on 09/24/2015 07:11 PM
If you look closely at the Commercial Space Act. Item #4 would qualify.  Congress could decide that having the SLS as a backup to the FH until Vulcan is online is consistent with national security objectives.  SpaceX and ULA could sue but they would loose the lawsuit. 

Quote
4) the use of space transportation services from United States commercial providers is inconsistent with national security objectives;
As Jim alluded to, the law states that the determination would be made by the Secretary of the Air Force:
Quote
TITLE II--FEDERAL ACQUISITION OF SPACE TRANSPORTATION SERVICES

(a) In General.--Except as otherwise provided in this section, the Federal Government shall acquire space transportation services from United States commercial providers whenever such services are required in the course of its activities. To the maximum extent practicable, the Federal Government shall plan missions to accommodate the space transportation services capabilities of United States commercial providers.
(b) Exceptions.--The Federal Government shall not be required to acquire space transportation services under subsection (a) if, on a case-by-case basis, the Administrator or, in the case of a national security issue, the Secretary of the Air Force, determines that--
.
.
.
(4) the use of space transportation services from United States commercial providers is inconsistent with national security objectives;
(My emphasis.)
Title: Re: SLS General Discussion Thread 2
Post by: Brovane on 09/24/2015 07:28 PM


In my opinion, Congress would be forced to either; pay money to ULA to keep launch capability for DIVH, accept that FH is the only vehicle that can meet the full range of DOD payloads until Vulcan is in service, or use the SLS as a backup to the FH for DOD launches until the Vulcan is online.

Note quite. Vulcan is planned to be online in 2019(1 year after SLS). FH will compete with Atlas and Delta from about 2016-2018. Delta is phased out in 2018,which allows plenty of time for planning and transitioning. Vulcan is up by about 2020/2019. There is hardly any gap. FH isn't the only vehicle that can meet the the full range of payloads unless relations with the Russians get much worse. Atlas launches most payloads with Delta only handling the largest.

Congress can not be forced to do anything by AF policy. However ULA and Space X could sue if an payload that they could launch is put on SLS.  Those exceptions are for specific purposes.

This assumes the Vulcan Development proceeds without any problems/delays.  ULA doesn't even have the  commitment from Boeing and LM for full funding for development of the Vulcan.  They are going quarter by quarter right now for funding. 

If you look closely at the Commercial Space Act. Item #4 would qualify.  Congress could decide that having the SLS as a backup to the FH until Vulcan is online is consistent with national security objectives.  SpaceX and ULA could sue but they would loose the lawsuit. 

Quote
4) the use of space transportation services from United States commercial providers is inconsistent with national security objectives;

Delta Heavy won't go offline until Vulcan is online, so won't apply and Congress would be getting into to same mess it did back in the 80ies with respect to the Shuttle. Taking payloads away from the private sector is not an wise move for either the exploration of space or national security.  There is no need to use SLS as back up to Vulcan or FH. The smarter, cheaper and less politically dangerous move would just be to wait until Vulcan is online.

If the Delta Heavy doesn't have any launch contracts why would ULA keep the production line open and launch facilities in-place until the Vulcan is online?  Without any launch contracts who is paying for that? 
Title: Re: SLS General Discussion Thread 2
Post by: Brovane on 09/24/2015 07:33 PM
If you look closely at the Commercial Space Act. Item #4 would qualify.  Congress could decide that having the SLS as a backup to the FH until Vulcan is online is consistent with national security objectives.  SpaceX and ULA could sue but they would loose the lawsuit. 

Quote
4) the use of space transportation services from United States commercial providers is inconsistent with national security objectives;
As Jim alluded to, the law states that the determination would be made by the Secretary of the Air Force:
Quote
TITLE II--FEDERAL ACQUISITION OF SPACE TRANSPORTATION SERVICES

(a) In General.--Except as otherwise provided in this section, the Federal Government shall acquire space transportation services from United States commercial providers whenever such services are required in the course of its activities. To the maximum extent practicable, the Federal Government shall plan missions to accommodate the space transportation services capabilities of United States commercial providers.
(b) Exceptions.--The Federal Government shall not be required to acquire space transportation services under subsection (a) if, on a case-by-case basis, the Administrator or, in the case of a national security issue, the Secretary of the Air Force, determines that--
.
.
.
(4) the use of space transportation services from United States commercial providers is inconsistent with national security objectives;
(My emphasis.)

Yeah as if Congress doesn't have any influence on the Secretary of the USAF..........

http://www.nasaspaceflight.com/2012/02/sls-dod-market-secondary-payloads-potential/ (http://www.nasaspaceflight.com/2012/02/sls-dod-market-secondary-payloads-potential/)

A article was even written in 2012 on this site about SLS DOD support. 
Title: Re: SLS General Discussion Thread 2
Post by: Jim on 09/24/2015 07:41 PM

If the Delta Heavy doesn't have any launch contracts why would ULA keep the production line open and launch facilities in-place until the Vulcan is online?  Without any launch contracts who is paying for that? 

Because contracts don't go out that far. 

There is a standing requirement (outside of NASA's needs) of 3-4 east coast and 2-3 west coast DIVH per decade.
Title: Re: SLS General Discussion Thread 2
Post by: Jim on 09/24/2015 07:43 PM

http://www.nasaspaceflight.com/2012/02/sls-dod-market-secondary-payloads-potential/ (http://www.nasaspaceflight.com/2012/02/sls-dod-market-secondary-payloads-potential/)

A article was even written in 2012 on this site about SLS DOD support. 

It does nothing to support your case.  That is just an SLS marketing pitch from the SLS program.  The DOD has no interest. 
Title: Re: SLS General Discussion Thread 2
Post by: pathfinder_01 on 09/24/2015 08:25 PM


If the Delta Heavy doesn't have any launch contracts why would ULA keep the production line open and launch facilities in-place until the Vulcan is online?  Without any launch contracts who is paying for that?

It has contracts. Flights are booked years in advance and it can take two years from when an rocket was ordered to when it is launched. Delta will be available for booking until Vulcan is online. ULA is on the hook for any Delta flights already ordered. Vulcan will be able to accept some launch contracts before it's first flight as well. SLS can not gain payloads this way. The short is that payloads book flights years in advance and payloads can be shifted between launchers if needed(with negotiation).
Title: Re: SLS General Discussion Thread 2
Post by: 93143 on 09/24/2015 09:16 PM
As to "tech enhancements and right-sizing", where are you hearing this?  NASA would have to pay Boeing more to change their current setup, and they have already locked in their current capabilities.

I'm talking about what they've already locked in.  You yourself mentioned how they've been bragging about how efficient their new tooling is and how much touch labour it will save, and in the very post I'm quoting you mention the fact that they've designed the infrastructure for low-rate production.  (Furthermore, ATK and Rocketdyne have been working to reduce costs as well.)

But here's the thing - we don't know of any recurring cost estimates made since that stuff was figured out.  The estimates I've been working with all predate the start of the SLS program, and are for a directly Shuttle-derived vehicle like Jupiter.  Even the ESD Integration estimates were based directly on Shuttle and Ares; it straight-up says so in the document, and the fact that the estimated fixed cost is very similar to that of the J-246 would seem to back this up.  And since SLS is still deep in development, operational cost savings wouldn't yet be evident in the budget numbers (though the early estimates of cost to IOC did drop by a few billion dollars before climbing partway back up).

Hence my claim that we don't yet know what effect the new approach will have on ops costs.

...

As an aside, I should acknowledge that the fact that they seem to be understaffed for production of two cores per year probably adds somewhat to the marginal cost of going to that rate.  But if you look at the staffing numbers associated with production and how they compare with those for Shuttle, it's hard to see how that by itself could increase it by a whole lot.  How much are these people paid?

Quote
You keep talking about this like there is some unseen effort to significantly reduce costs.  Unless you can point it out in statements NASA or Boeing has made, it's not there.

You haven't been paying attention.  They've been going on about "affordability" and "sustainability" since the program started, and the actual work being done seems to be at least somewhat consistent with the rhetoric.

http://www.nasaspaceflight.com/2011/08/boeing-complete-sls-pathfinder-tank-maf-et-operations-end/
http://spacenews.com/nasa-centers-see-commonality-key-sls-affordability/
http://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/20120003874.pdf
http://www.nasaspaceflight.com/2012/11/dynetics-pwr-liquidize-sls-booster-competition-f-1-power/
http://www.americaspace.com/?p=25799
http://www.nasaspaceflight.com/2013/01/the-dark-knights-atks-advanced-booster-revealed-for-sls/
http://www.parabolicarc.com/2013/10/28/atk-build-sls-boosters-cheaper-peformance/
http://www.nasaspaceflight.com/2013/02/sls-new-buckling-standards-drops-super-light-alloy/
http://www.parabolicarc.com/2013/03/31/3-d-printing-makes-its-mark-in-nasas-new-engine/
http://aviationweek.com/space/aerojet-rocketdyne-cranking-expendable-ssme
http://spacenews.com/36012tooling-processes-coming-together-for-affordable-space-launch-system/
Title: Re: SLS General Discussion Thread 2
Post by: oldAtlas_Eguy on 09/25/2015 04:48 PM
The whole point about SLS unit costs are that the production line is being setup to be at its lowest per unit cost at 1 per year. A higher or lower rate will increase the per unit cost. There is also a maximum rate due to the design of the tooling of 2 per year. To do higher rates a new set of tooling would be needed designed to support 5 or more (10) vehicle production rate per year. This is an overhead cost plus the unit margin costs such that until you get to a production rate of >3 the per unit cost will be more than the current 1 per year. As you move to the closer to 10 per year you may eventually get to the often quoted unit cost amount of $300M.

The conclusion is that for production rates from .5 to 3 per year the unit costs ripple up and down but generally stay almost the same or greater than the current setup for 1 per year amount.
Title: Re: SLS General Discussion Thread 2
Post by: 93143 on 09/25/2015 09:24 PM
Okay, first you should probably define what you mean by "unit cost".
Title: Re: SLS General Discussion Thread 2
Post by: the_other_Doug on 09/26/2015 01:51 AM
Postulate:  There is a defined (and funded) need to build 3 to 4 SLS rockets a year for a period of 20 to 30 years.  (This is the postulate, not an argument -- trying to knock down the postulate short-circuits the purpose of the question.)

Given this, what do you need to do in order to fulfill that production rate?  If the factory ain't big enough, do you farm out work to other providers, rather like the von Braun team built the first Saturn I stages and then farmed out the work to Chrysler?  Do you expand the factory?

Is the issue lack of sufficient tooling?  If so, what is the extra cost of developing a second and/or third tooling set?  Heck, aren't they making spares of most of the most important tooling, anyway?  If so, how much additional does it cost to make another set or two?

I'm not trying to downplay the potential costs and difficulties in ramping up SLS production.  I'm just trying to understand where these costs and difficulties mostly lie.
Title: Re: SLS General Discussion Thread 2
Post by: Coastal Ron on 09/26/2015 02:24 AM
Given this, what do you need to do in order to fulfill that production rate?  If the factory ain't big enough, do you farm out work to other providers, rather like the von Braun team built the first Saturn I stages and then farmed out the work to Chrysler?  Do you expand the factory?

You expand the current factory.  The transportation requirements are very unique, and few aerospace factories would qualify.

Quote
Is the issue lack of sufficient tooling?

Apparently so, but I'm not sure we have enough public information to fully answer this.

Quote
If so, what is the extra cost of developing a second and/or third tooling set?

The first set of tooling is usually the most expensive, but when it comes to custom tooling you might not get a break on the cost per unit, but you obviously wouldn't need to pay for the development costs.

Quote
Heck, aren't they making spares of most of the most important tooling, anyway?  If so, how much additional does it cost to make another set or two?

Yes, there would be both consumables and repairable items that are already in the factory, so you would just order more of those.  But the fixtures would be unique, such as the Vertical Assembly Center welding tool.

As a reference, here is a NASA article about the SLS tooling:

Tooling Up to Build the World's Largest Rocket (http://www.nasa.gov/centers/marshall/news/news/releases/2013/13-080.html) | NASA

You may not need duplicates of everything, but that depends on how Boeing and their contractors designed them, or how NASA spec'd them.

Expanding your current factory also allows for economies of scale, especially in production support functions such as manufacturing engineers, which have to be at the factory they support, so one factory only requires a fractional increase in manufacturing engineering staffing when expanded, whereas a second factory requires a doubling of staffing.
Title: Re: SLS General Discussion Thread 2
Post by: Jim on 09/26/2015 02:31 AM
Postulate:  There is a defined (and funded) need to build 3 to 4 SLS rockets a year for a period of 20 to 30 years.  (This is the postulate, not an argument -- trying to knock down the postulate short-circuits the purpose of the question.)

Given this, what do you need to do in order to fulfill that production rate? 

Doesn't do any good if it could.  The national infrastructure for spacecraft has to be beefed up if SLS is to fly more than Orion or 15ft diameter payloads.
Title: Re: SLS General Discussion Thread 2
Post by: oldAtlas_Eguy on 09/26/2015 03:14 PM
Postulate:  There is a defined (and funded) need to build 3 to 4 SLS rockets a year for a period of 20 to 30 years.  (This is the postulate, not an argument -- trying to knock down the postulate short-circuits the purpose of the question.)

Given this, what do you need to do in order to fulfill that production rate? 

Doesn't do any good if it could.  The national infrastructure for spacecraft has to be beefed up if SLS is to fly more than Orion or 15ft diameter payloads.
Jim,
This is a thought experiment seeking if it is possible and what it would take to increase the production rate of SLS. The second part is what effect on unit cost would this have?

The justification for such higher launch rate/production rates is a separate question. From all the work to optimize at 1 per year, says that all the projections on launch rate does not go over 2 per year and averages to 1 per year over the period of through 2030. At an average of 1 per year starting after 2021 (EM-2)the projection is that only 8 more SLS launches would possibly occur through 2030.

If the program lasts through 2030 then only 10 SLSs will be built and fly between now and 2030 (15 years period). In that 15year period it is possible that a large commercial launcher (>=100mt) or other demonstrated capabilities that could do the same with smaller amounts (distributed launch) could come into existence.

edit added:
If the high launch costs are what is controlling the launch rate what would the launch rate be if the per launch costs were 1/2, 1/4 or even 1/10 of that of the SLS.
Title: Re: SLS General Discussion Thread 2
Post by: muomega0 on 09/26/2015 04:46 PM
Hence my claim that we don't yet know what effect the new approach will have on ops costs.

You haven't been paying attention.  They've been going on about "affordability" and "sustainability" since the program started, and the actual work being done seems to be at least somewhat consistent with the rhetoric.

http://www.nasaspaceflight.com/2011/08/boeing-complete-sls-pathfinder-tank-maf-et-operations-end/
http://spacenews.com/nasa-centers-see-commonality-key-sls-affordability/
http://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/20120003874.pdf
http://www.nasaspaceflight.com/2012/11/dynetics-pwr-liquidize-sls-booster-competition-f-1-power/
http://www.americaspace.com/?p=25799
http://www.nasaspaceflight.com/2013/01/the-dark-knights-atks-advanced-booster-revealed-for-sls/
http://www.parabolicarc.com/2013/10/28/atk-build-sls-boosters-cheaper-peformance/
http://www.nasaspaceflight.com/2013/02/sls-new-buckling-standards-drops-super-light-alloy/
http://www.parabolicarc.com/2013/03/31/3-d-printing-makes-its-mark-in-nasas-new-engine/
http://aviationweek.com/space/aerojet-rocketdyne-cranking-expendable-ssme
http://spacenews.com/36012tooling-processes-coming-together-for-affordable-space-launch-system/

The new estimate is that it takes over 3B/yr to fly SLS/Orion from 2018 to 2027 for SLS/Orion yearly solo shots.

It then takes over $8B/year per the NASA budget (http://i2.wp.com/www.universetoday.com/wp-content/uploads/2015/01/NASA-2015_Budget21.jpg) to fly the SLS 2028 to 2046 mission set (http://forum.nasaspaceflight.com/index.php?topic=38507.msg1429504#msg1429504) as it includes ISS Splashdown and abandons commercial crew. (Space Ops 3.83B, Exploration 4.35B, Crew 0.8B, R&D 0.42B). 

With only a flight per year in the early 2020s, it also adds $1B/yr Delta Heavy flights.  If you start with the wrong architecture and LV/components, so much for afforadability and sustainability.
Title: Re: SLS General Discussion Thread 2
Post by: oldAtlas_Eguy on 09/26/2015 05:05 PM
Hence my claim that we don't yet know what effect the new approach will have on ops costs.

You haven't been paying attention.  They've been going on about "affordability" and "sustainability" since the program started, and the actual work being done seems to be at least somewhat consistent with the rhetoric.

http://www.nasaspaceflight.com/2011/08/boeing-complete-sls-pathfinder-tank-maf-et-operations-end/
http://spacenews.com/nasa-centers-see-commonality-key-sls-affordability/
http://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/20120003874.pdf
http://www.nasaspaceflight.com/2012/11/dynetics-pwr-liquidize-sls-booster-competition-f-1-power/
http://www.americaspace.com/?p=25799
http://www.nasaspaceflight.com/2013/01/the-dark-knights-atks-advanced-booster-revealed-for-sls/
http://www.parabolicarc.com/2013/10/28/atk-build-sls-boosters-cheaper-peformance/
http://www.nasaspaceflight.com/2013/02/sls-new-buckling-standards-drops-super-light-alloy/
http://www.parabolicarc.com/2013/03/31/3-d-printing-makes-its-mark-in-nasas-new-engine/
http://aviationweek.com/space/aerojet-rocketdyne-cranking-expendable-ssme
http://spacenews.com/36012tooling-processes-coming-together-for-affordable-space-launch-system/

The new estimate is that it takes over 3B/yr to fly SLS/Orion from 2018 to 2027 for SLS/Orion yearly solo shots.

It then takes over $8B/year per the NASA budget (http://i2.wp.com/www.universetoday.com/wp-content/uploads/2015/01/NASA-2015_Budget21.jpg) to fly the SLS 2028 to 2046 mission set (http://forum.nasaspaceflight.com/index.php?topic=38507.msg1429504#msg1429504) as it includes ISS Splashdown and abandons commercial crew. (Space Ops 3.83B, Exploration 4.35B, Crew 0.8B, R&D 0.42B). 

With only a flight per year in the early 2020s, it also adds $1B/yr Delta Heavy flights.  If you start with the wrong architecture and LV/components, so much for afforadability and sustainability.
Do you have a breakout for the $3B 2018-2027?

Edit added:

15 (2013-2028) years at $3B per year for a total of 8 flights is $45B or $5.65B average per flight costs including development. (Must add development costs to compare against pure commercial but then again there are few true pure commercial developments). Removing development costs (6 years and the first flight) gives $3.8B average per flight costs.
Title: Re: SLS General Discussion Thread 2
Post by: clongton on 09/26/2015 06:48 PM
If the Delta Heavy doesn't have any launch contracts why would ULA keep the production line open and launch facilities in-place until the Vulcan is online?  Without any launch contracts who is paying for that? 

Actually it doesn't need any contracts to keep the production line open and the launch facilities in place. The DoD pays ULA $1B (that's "billion" with a B) cash each year to do just that - no launches required and no strings attached.
Title: Re: SLS General Discussion Thread 2
Post by: pathfinder_01 on 09/26/2015 07:54 PM
If the Delta Heavy doesn't have any launch contracts why would ULA keep the production line open and launch facilities in-place until the Vulcan is online?  Without any launch contracts who is paying for that? 

Actually it doesn't need any contracts to keep the production line open and the launch facilities in place. The DoD pays ULA $1B (that's "billion" with a B) cash each year to do just that - no launches required and no strings attached.

That payment is being phased out.
Title: Re: SLS General Discussion Thread 2
Post by: Coastal Ron on 09/26/2015 07:55 PM
As to "tech enhancements and right-sizing", where are you hearing this?  NASA would have to pay Boeing more to change their current setup, and they have already locked in their current capabilities.

I'm talking about what they've already locked in.  You yourself mentioned how they've been bragging about how efficient their new tooling is and how much touch labour it will save, and in the very post I'm quoting you mention the fact that they've designed the infrastructure for low-rate production.  (Furthermore, ATK and Rocketdyne have been working to reduce costs as well.)

The only way to know if you're saving money on something is to know what the costs were before you were saving money, and then compare that to what you're now paying.  And since the SLS is a completely new design, with new tooling and a new contractor (Shuttle ET was LM, SLS is Boeing), there is no way to know what any costs might have been if they hadn't done what is actually their job - to build a quality product at the lowest practical cost.

Claiming cost savings without a basis of comparison is pure advertising, not facts.

If you disagree, then please point out what the costs were supposed to be before they implemented the supposed cost savings.

Quote
As an aside, I should acknowledge that the fact that they seem to be understaffed for production of two cores per year probably adds somewhat to the marginal cost of going to that rate.  But if you look at the staffing numbers associated with production and how they compare with those for Shuttle, it's hard to see how that by itself could increase it by a whole lot.  How much are these people paid?

Give up on trying to figure out "marginal cost".  There are no facts to use to calculate it.  No one in the public has enough facts about the cost of the SLS.

And stop trying to equate the manufacturing cost of the SLS to the Shuttle External Tank.  The SLS 1st stage is 3.2X more mass than the Shuttle External Tank, and it has obvious design differences.  Plus the Shuttle ET was built by Lockheed Martin in serial production over a period of decades, whereas the SLS is being built by Boeing and it's just starting to get the tooling to work.
Title: Re: SLS General Discussion Thread 2
Post by: Oli on 09/26/2015 09:52 PM
Give up on trying to figure out "marginal cost".  There are no facts to use to calculate it.

93143 has provided sources. They give us a rough idea about the marginal cost. We also have the "official" $500m number from NASA.
Title: Re: SLS General Discussion Thread 2
Post by: sdsds on 09/27/2015 03:57 AM
Give up on trying to figure out "marginal cost".  There are no facts to use to calculate it.

93143 has provided sources. They give us a rough idea about the marginal cost. We also have the "official" $500m number from NASA.

Rather than advising people to give up, it's probably better to help the questioner see that their question might somehow get better answers if it were phrased differently.

I wonder, for example: "What would be the cost of accelerating the SLS production and flight rate from one every 12 months to one every 10 months?"

That asks a question similar to one about "marginal" costs, though ... not quite the same.
Title: Re: SLS General Discussion Thread 2
Post by: 93143 on 09/27/2015 04:25 AM
If you disagree, then please point out what the costs were supposed to be before they implemented the supposed cost savings.

This isn't the first time anyone has designed a launch vehicle like this.  NLS-1 made it through PDR, and a lot of information is available publicly.  DIRECT's Jupiter was heavily studied and cost projections were made over a spectrum of flight rates for various configurations (I linked a graph earlier in the thread, if you'll recall).  And early versions of SLS were put through NASA's cost-estimating machine to produce (among other things) the ESD Integration Budget Availability Scenarios document from 2011, with costs based directly on Shuttle where applicable - including core stage costs being based on the ET.

The idea with Jupiter and proto-SLS was that the ET tooling and workforce would be reused to build core stages.  Similarly, the boosters were assumed to be done the same way they had always been done, before ATK's Value Stream Mapping exercise; the ESD Integration document based booster costs on the Ares I first stage, with no mention of cost savings associated with the "competitive booster" (which would have been hard to estimate at the time, since no proposals existed).  The ESD Integration document also mentions the RS-25E, but there is no indication of any cost savings associated with it either; the RS-25 costs are simply said to be based on the SSME.

So the cost estimates I showed you earlier in the thread were exactly what you just asked for.

Quote
Quote
But if you look at the staffing numbers associated with production and how they compare with those for Shuttle
And stop trying to equate the manufacturing cost of the SLS to the Shuttle External Tank.

I am not doing that.  I am comparing MAF's sub-1000 SLS workforce with its ~2500-man STS workforce, with the intent of implying that the increase in workforce required to operate Boeing's advanced low-rate automated production equipment at full speed rather than half speed is unlikely, by itself, to account for a large* difference in marginal cost vs. using the old Shuttle tank production equipment with the full workforce already present.  A similar argument applies to the boosters.

* You seem to be implicitly defending the idea that the SLS marginal cost to go from one launch per year to two could reasonably be as high as $1B.  What I am saying here is that the workforce delta alone is not going to bridge the gap between the numbers I've shown and the numbers you're trying to imply are plausible.

We also have the "official" $500m number from NASA.

Has that number ever been shown to be a marginal cost estimate for SLS?  I thought people just started assuming it was because they couldn't imagine it being anything else.

The whole point about SLS unit costs are that the production line is being setup to be at its lowest per unit cost at 1 per year. A higher or lower rate will increase the per unit cost. There is also a maximum rate due to the design of the tooling of 2 per year. To do higher rates a new set of tooling would be needed designed to support 5 or more (10) vehicle production rate per year. This is an overhead cost plus the unit margin costs such that until you get to a production rate of >3 the per unit cost will be more than the current 1 per year. As you move to the closer to 10 per year you may eventually get to the often quoted unit cost amount of $300M.

The conclusion is that for production rates from .5 to 3 per year the unit costs ripple up and down but generally stay almost the same or greater than the current setup for 1 per year amount.
Okay, first you should probably define what you mean by "unit cost".

Well?

Your account doesn't seem internally consistent, given what I know of industrial production.  The second paragraph, as well as the first couple sentences of the first one, make plenty of sense if you're talking about some kind of incremental or marginal production cost.  But later in the first paragraph you add overhead associated with extra production equipment to "unit margin costs" to get unit cost, which implies total cost, which in turn implies that you're claiming that the total cost of having and running the facility at MAF would be more than twice as high at two cores per year as at one core per year.  And if that's what you're claiming, well...  citation needed.

Also, I hear there's plenty of floor space at MAF, so I'm not sure why it would be impossible to set up for rates between 2 and 5 per year.  Is this inside information you're supplying?
Title: Re: SLS General Discussion Thread 2
Post by: Coastal Ron on 09/27/2015 05:08 AM
Give up on trying to figure out "marginal cost".  There are no facts to use to calculate it.

93143 has provided sources. They give us a rough idea about the marginal cost. We also have the "official" $500m number from NASA.

No actual contracts have been signed for building a production SLS, and the discussion has been about the "marginal costs" for production.  Boeing still hasn't figured out whether the 1st and 2nd pre-production units (SLS-1 &-2) will be able to be built as planned.

As to numbers from "NASA", NASA used to claim low marginal costs for the Shuttle, but now know at the end of the program that each flight cost $1.2B without development factored in.  Which is why public facts are the only numbers that can be trusted.

If you disagree, then please point out what the costs were supposed to be before they implemented the supposed cost savings.

This isn't the first time anyone has designed a launch vehicle like this.  NLS-1 made it through PDR, and a lot of information is available publicly.

When you talk about "marginal cost", that is for production SLS units.  And so far not even a development or pre-production SLS has been built, much less flown.  The NLS-1, which never made it into production, was based on the Shuttle External Tank (ET), and the SLS 1st stage is a different design from the ET and 3.2X more mass.

The last contract I could find on the cost of the ET showed that it cost $173M/ea back in 2010 when procured in quantities of at least 17 units.  So if the SLS 1st stage cost 3.2X the Shuttle ET that would be $554M/ea - no engines or other accessories.  Of course that ignores a likely difference in contract quantity, since I doubt Congress will allow NASA to buy 17 production SLS 1st stages right away (meaning no volume cost breaks).  But it could be argued that the SLS 1st stage will require less than 3.2X the amount of labor, and that the $/lb of the raw material is less expensive than the Shuttle ET (the cost of AL has fluctuated up and down 20% since 2010).

Lots of factors, but few facts about the production version of the SLS - because NASA and Boeing haven't built any SLS yet, so they don't know what a successfully built SLS consists of.

But I'll leave it at that for now...
Title: Re: SLS General Discussion Thread 2
Post by: Proponent on 09/27/2015 11:31 AM
Even the ESD Integration estimates were based directly on Shuttle and Ares; it straight-up says so in the document, and the fact that the estimated fixed cost is very similar to that of the J-246 would seem to back this up.

To exactly which document do you refer?  If to "ESD Integration; Budget Availability Scenarios" dated 19 August 2011 (attached to this post (http://forum.nasaspaceflight.com/index.php?topic=19892.msg811814#msg811814)), where does the statement appear?
Title: Re: SLS General Discussion Thread 2
Post by: oldAtlas_Eguy on 09/27/2015 04:35 PM
Marginal Cost
http://www.businessdictionary.com/definition/marginal-cost.html#ixzz3mxBMPvv1 (http://www.businessdictionary.com/definition/marginal-cost.html#ixzz3mxBMPvv1)
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The increase or decrease in the total cost of a production run for making one additional unit of an item. It is computed in situations where the break-even point has been reached: the fixed costs have already been absorbed by the already produced items and only the direct (variable) costs have to be accounted for.

Unit Cost
http://www.businessdictionary.com/definition/unit-cost.html#ixzz3mxC2axbo (http://www.businessdictionary.com/definition/unit-cost.html#ixzz3mxC2axbo)
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Expenditure incurred in producing one unit of a good or service, computed usually as average cost.

Marginal costs are a tricky thing. It should be a constant value. But sometimes it varies as the capabilities of production are reached and another production line must be added to produce the next unit. This makes the Marginal cost value sometimes pop up with a large value between the consecutive numbers of items to be built. What I am saying is that going from 1 per year to 2 per year is not very significant in that no new equipment or lines are required just more people (incremental cost) no additional overhead cost (fixed cost). But going from 2 to 3 per year there is significant overhead costs (fixed costs) that must be added when the additional set of tooling is added, almost the same costs as that to produce 1 per year. Because some tooling may not need a second set this increase is not exactly the same but some percentage of the total.
Meaning that the marginal cost going from 2 to 3 per year is much greater than the marginal cost of going from 1 to 2.

If the production line is set up correctly then the Unit costs should decrease in an exponential rate as more units a fixed incremental cost are produced for the set fixed costs. Also these incremental costs may themselves be affected by the number of produced items by making the personnel more efficient at producing items thereby additionally lowering the Incremental and the resulting Unit costs even more.

But what I am saying is the SLS is not this case, and any attempt to predict costs are going to be a very rough estimate and most likely to be wrong by even as much as a factor of 2.

The specifics of the problem are this:
1) For going from 1 to 2 the fixed costs are the same and the incremental cost per unit is the same so the marginal cost is equal to the incremental cost.
2) For going from 2 to 3 the fixed costs increase by 50-80% but the incremental costs are the same. So the marginal cost for going from 2 to 3 is the 50-80% increase in fixed cost plus an incremental cost.
3) Going from 3 to 4 is the same marginal cost value as that for going from 1 to 2.

What this does is the average cost (Unit cost) fluctuates up and down and does not follow a nice exponential curve.
Title: Re: SLS General Discussion Thread 2
Post by: sdsds on 09/27/2015 06:56 PM
ISTM a lot depends on how much slack exists in the nominal schedules of the various production tools, and whether there are opportunities for the upstream tools to "get ahead" a bit without creating a congestion in the flow of parts.

For example, in August Jason Davis of The Planetary Society photographed the Gore Weld Tool, where an EM-1 flight article tank dome was being welded.
http://www.planetary.org/multimedia/space-images/spacecraft/eft-1-aft-liquid-oxygen-tank.html

Presumably by now that dome is complete. But it can't move to the Vertical Assembly Center yet, because that tool suffered a misalignment problem. So is it still sitting on the Gore Weld Tool, preventing the welding of the next dome needed for EM-1? Is there a holding fixture where the completed dome can be temporarily stored? As regards costs, is it possible that for example to increase the production rate Michoud would need more of these temporary storage fixtures? They wouldn't be expensive, perhaps, but they aren't zero cost either....
Title: Re: SLS General Discussion Thread 2
Post by: 93143 on 09/27/2015 09:15 PM
NASA used to claim low marginal costs for the Shuttle, but now know at the end of the program that each flight cost $1.2B without development factored in.

Apples to oranges.  The $1.2B number is the whole program's cost in modern dollars (minus development) divided by the flight rate.  It thus includes not only fixed costs during operational years, but also the costs incurred while the program was grounded after Challenger and Columbia.  And I'm pretty sure it includes SFS and ongoing development too.  This is not in the least comparable to anything deserving of the name "marginal cost".

Even back before STS was developed, when they still had high hopes for the idea, they managed to nail the marginal cost within a factor of two; what killed them was fixed cost divided by flight rate.  After 30 years of experience with running STS, and even more with various expendables, the economics of a Shuttle-derived inline launcher are much better understood than the economics of running STS were back in the early 1970s.

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When you talk about "marginal cost", that is for production SLS units.  And so far not even a development or pre-production SLS has been built, much less flown.

Yes, but estimates for the cost of such a system, based on the old technology, exist.  And at multiple flight rates, so a marginal cost can be calculated directly from the given data.  I have shown this.

Can you show me that it is plausible that the marginal cost of increasing the SLS production rate from one unit per year to two units per year could increase from ~$350M or so to ~$1000M, given the known scope of the changes?  I doubt it.

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The last contract I could find on the cost of the ET showed that it cost $173M/ea back in 2010 when procured in quantities of at least 17 units.  So if the SLS 1st stage cost 3.2X the Shuttle ET that would be $554M/ea - no engines or other accessories.

Apples to oranges again.  We were discussing marginal costs associated with changes in flight rate, not a particular component's share of the total recurring costs.

To exactly which document do you refer?  If to "ESD Integration; Budget Availability Scenarios" dated 19 August 2011 (attached to this post (http://forum.nasaspaceflight.com/index.php?topic=19892.msg811814#msg811814)), where does the statement appear?

Right below every sand chart, it says the following:

FY11:  21st CGS = CxP GO; MPCV = CxP Orion + EVA + MO; SLS =Ares I FS (Booster / Avionics), Ares I J-2X (US Engine), SSP SSME (Core Engine), SSP ET (Core Stage), Ares I PM / VI / S&MA / FITO (Prog Integ)

I may have overstated the clarity of the statement somewhat; how would you interpret this?

The specifics of the problem are this:
1) For going from 1 to 2 the fixed costs are the same and the incremental cost per unit is the same so the marginal cost is equal to the incremental cost.
2) For going from 2 to 3 the fixed costs increase by 50-80% but the incremental costs are the same. So the marginal cost for going from 2 to 3 is the 50-80% increase in fixed cost plus an incremental cost.
3) Going from 3 to 4 is the same marginal cost value as that for going from 1 to 2.

Thank you.  That's not actually a problem in this case, since the discussion has been centered on changes in flight rate within the known limits of the production equipment and launch facilities.  I did acknowledge that the tooling maxes out at two per year (launch can do three, so you can bank cores for a surge), and I did mention the bump up on DIRECT's EELV charts at the point where the factory maxes out (I figured the implications for SLS as built were pretty clear).

As regards costs, is it possible that for example to increase the production rate Michoud would need more of these temporary storage fixtures? They wouldn't be expensive, perhaps, but they aren't zero cost either....

That's an interesting question.  What, exactly, is the bottleneck that prevents the current setup from exceeding two cores per year?  It seems odd that no individual tool would be capable of any more than that; it's an awfully slow production rate even for such large components...
Title: Re: SLS General Discussion Thread 2
Post by: Coastal Ron on 09/27/2015 11:16 PM
...We were discussing marginal costs associated with changes in flight rate...

What was the original supposition that lead to this discussion about "marginal cost"?  I think it's been a while, and I've forgotten.

Is "marginal cost" something that will play into the discussion about the future of the SLS?  In other words, is a future NASA Administrator going to be called in front of Congress and asked what the "marginal cost" is of the SLS, and that their answer will determine whether an additional SLS is authorized?

Or are we talking about something that only accountants get excited about?
Title: Re: SLS General Discussion Thread 2
Post by: spacenut on 09/28/2015 12:00 AM
I think the maximum production stated by NASA is by using the current or existing workforce.  I think more can be made per year IF they ramp up production by adding extra shifts, and or weekend shifts.  They were able to producte what, 4-6 Saturn V cores per year.  Why not produce the same SLS cores.  Surely they can produce more solid cores than two per year or even 4 per year.  How long did it take them to produce 1,000 Minutemen's in the 1960's?  4-5 years?
Title: Re: SLS General Discussion Thread 2
Post by: pathfinder_01 on 09/28/2015 12:05 AM

That's an interesting question.  What, exactly, is the bottleneck that prevents the current setup from exceeding two cores per year?  It seems odd that no individual tool would be capable of any more than that; it's an awfully slow production rate even for such large components...

Not really. The plant was designed from the get go with a certain amount of production in mind. Tooling, processes and procedures don’t scale the same efficiency at every production rate.  The short to make more of something you may need to change tooling to tooling supportive of that production rate.  Processes and procedures likewise. Otherwise just simply adding more tools and adding more people will not dropping per unit costs all that much.

An good example is me attempting to bake ten cakes in my kitchen vs. an bakery or an commercial kitchen. My oven will only fit 3 at an time. An bakery or commercial kitchen could have larger ovens or block long ovens that bake the cake as it travels along the line.(i.e. Tooling).

I could not lift or bake ten cakes worth of batter, if I had it. I would have to break it up into batches and that would slow me down considerably. An bakery could use an hoist to lift into a batter measuring machine(Process).

Having enough staffing to cover all sifts, vacations, sick time or produce product at an min. amount is not an problem when there is only one person. However in an production enviroment that comes into play.(Procedures)

NASA simply desgined the factory for SLS and for an flight rate of 1-2 an year and it likely was an attractive thing to do(complies with the law--which states nothing about production rate). President not actively engaged(not his baby) and does nothing to further his goal(commercialization of human spaceflight). Saves money(designing for smaller scales of production is cheaper than larger scales). All parties are fine with it.

It isn't one tool, it is the whole thing.

Title: Re: SLS General Discussion Thread 2
Post by: Coastal Ron on 09/28/2015 03:59 AM
I think the maximum production stated by NASA is by using the current or existing workforce.  I think more can be made per year IF they ramp up production by adding extra shifts, and or weekend shifts.  They were able to producte what, 4-6 Saturn V cores per year.  Why not produce the same SLS cores.  Surely they can produce more solid cores than two per year or even 4 per year.  How long did it take them to produce 1,000 Minutemen's in the 1960's?  4-5 years?

Given enough time and money, anything is possible.

As to the current SLS production capabilities, from a SpaceNews article this year:

"Boeing has Michoud set up to stamp out enough stages for one SLS a year — two at most with the factory’s current manufacturing capabilities, and then only if NASA pours more money and personnel into the facility."

Also, and this sometimes gets lost on people, you have to have a need to produce more...
Title: Re: SLS General Discussion Thread 2
Post by: Coastal Ron on 09/28/2015 04:32 AM

That's an interesting question.  What, exactly, is the bottleneck that prevents the current setup from exceeding two cores per year?  It seems odd that no individual tool would be capable of any more than that; it's an awfully slow production rate even for such large components...

Not really. The plant was designed from the get go with a certain amount of production in mind. Tooling, processes and procedures don’t scale the same efficiency at every production rate.

Factories cost money, and everything in them has a cost.  So Boeing was only asked to build a factory that met NASA's requirements, which apparently was a minimum of one per year with the ability with additional NASA funding to increase to two per year.

To go above two per year depends on the tooling and various work centers.  I've done capacity planning for a high volume consumer electronics factory, and it's not alway simple reasons why a work center can't scale easily, especially when what you're doing is "state of the art".  And not all of the constraints are in your factory, it could be the constraint is with your supply chain (like Boeing experienced with fasteners for the 787).

Out of the six "substantial" welding tools for the cryogenic core stage on SLS, some of them might already have plenty of available capacity to go above 2/year, but that one particular tool (like maybe the Vertical Assembly Center) is the bottleneck.  We would need to know throughput time for each center to better understand the constraints, but even the proposed Mars plan doesn't need more than two per year until the late 2020's, so this is not a near-term need.
Title: Re: SLS General Discussion Thread 2
Post by: spacenut on 09/28/2015 07:38 PM
Someone said, somewhere here, that when facility to manufacture Saturn V 1st and 2nd stages were for 6 Saturn V's per year.  So, the facility can at least do 6.  So, can ATK manufacture 12 solid boosters a year to match?  If they want to get serious about going to Mars, they will have to manufacture more than two per year, even if you only went to Mars every two years.  The VAB can process at least 4 at a time.  It has 4 bays.  They would have to build at least 4 platforms.   I guess if they are going to Mars using SLS, they are probably going to have to use other launchers to launch components, fuel, SEP tugs, habitats, or something to LEO or to L2 and assemble to go to Mars.  More SLS launches would equal less in space assembly. 
Title: Re: SLS General Discussion Thread 2
Post by: Jim on 09/28/2015 07:55 PM
1.  Someone said, somewhere here, that when facility to manufacture Saturn V 1st and 2nd stages were for 6 Saturn V's per year.  So, the facility can at least do 6.

2.  The VAB can process at least 4 at a time.  It has 4 bays.  They would have to build at least 4 platforms.   

1.  Not true.  Space/volume does not determine capability.  The tooling does.  Anyways, it is a shared facility and there are other users

2.  See above. The 4 bays were never fully outfitted and even during shuttle, only two were outfitted.  Also, there is not only one pad for SLS.
Title: Re: SLS General Discussion Thread 2
Post by: Coastal Ron on 09/28/2015 07:55 PM
Someone said, somewhere here, that when facility to manufacture Saturn V 1st and 2nd stages were for 6 Saturn V's per year.  So, the facility can at least do 6.

The production line for a 2015 Ford Mustang is not the same as the production line that was used for the 1968 Ford Mustang, and so it is with the Saturn S-IC and the SLS 1st stage.  The amount of space that they need maybe completely different between the two.

And as a point of reference, at least according to Wikipedia:

"It took roughly seven to nine months to build the tanks and 14 months to complete a stage."

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So, can ATK manufacture 12 solid boosters a year to match?

I'm not sure why anyone is worried about being able to build enough SLS.  If the money is there, American industry can do just about anything - and the SLS is not a very complicated structure to build compared to what American industry has already done.  Your worry should be directed at the politicians that so far have not funded any production SLS flights, nor approved any missions that require the SLS.  If Congress coughs up the money, Boeing and it's suppliers will build it.

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I guess if they are going to Mars using SLS, they are probably going to have to use other launchers to launch components, fuel, SEP tugs, habitats, or something to LEO or to L2 and assemble to go to Mars.

The current NASA Mars proposal only assumes using the SLS.  No commercial or partner launchers.

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More SLS launches would equal less in space assembly.

There are trade-offs that negate that potential advantage.
Title: Re: SLS General Discussion Thread 2
Post by: Endeavour_01 on 09/28/2015 08:54 PM
NASA simply desgined the factory for SLS and for an flight rate of 1-2 an year and it likely was an attractive thing to do(complies with the law--which states nothing about production rate). President not actively engaged(not his baby) and does nothing to further his goal(commercialization of human spaceflight). Saves money(designing for smaller scales of production is cheaper than larger scales). All parties are fine with it.

It isn't one tool, it is the whole thing.

The evolvable Mars campaign has a maximum of 3 SLS launches during certain years. Do we really need to up the SLS production rate beyond 2 a year? Assuming NASA only uses SLS they could store extra cores made during the decade of once a year flights and then use them for the years that require 3 flights. Block 2B uses the same core and upper stage as Block 1B.

Alternatively you could tag team SLS with Vulcan and Falcon to launch some elements of the mission. That should get rid of the need to launch more than 2 SLS's a year.

From where I am sitting the production rate is fine for what is needed to have robust cis-lunar and Mars missions.
Title: Re: SLS General Discussion Thread 2
Post by: Coastal Ron on 09/28/2015 10:07 PM
The evolvable Mars campaign has a maximum of 3 SLS launches during certain years. Do we really need to up the SLS production rate beyond 2 a year? Assuming NASA only uses SLS they could store extra cores made during the decade of once a year flights and then use them for the years that require 3 flights. Block 2B uses the same core and upper stage as Block 1B.

Speaking from a production scheduling standpoint, sure, you probably could do that.  However from a budget standpoint that increases your spending upfront, and it decreases your vehicle flexibility to a certain degree (i.e. units built years in advance don't have current improvements).

But if the Mars plan gets approved, the cost of expanding the SLS production line will likely be assumed as part of the plan, and overall would probably only be in the single digits as far as overall program cost.

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Alternatively you could tag team SLS with Vulcan and Falcon to launch some elements of the mission. That should get rid of the need to launch more than 2 SLS's a year.

Sure, or even go all commercial.  Letting commercial launchers into the mix opens Pandora's box for NASA, since it will highlight the disadvantages of a government-run HLV transportation system - chief of which would be cost and redundancy.  Quite the conundrum...
Title: Re: SLS General Discussion Thread 2
Post by: Endeavour_01 on 09/28/2015 10:18 PM

Sure, or even go all commercial.  Letting commercial launchers into the mix opens Pandora's box for NASA, since it will highlight the disadvantages of a government-run HLV transportation system - chief of which would be cost and redundancy.  Quite the conundrum...

To quote Judge Dredd, "I knew you'd say that."   ;)

Going all commercial wouldn't work IMHO. You would run into capacity and volume issues that I have pointed out previously. A number of payloads as well as manned Orion launches wouldn't work on a Falcon Heavy or a Vulcan. The best bet is to use commercial to supplement SLS.
Title: Re: SLS General Discussion Thread 2
Post by: 93143 on 09/28/2015 10:49 PM
...We were discussing marginal costs associated with changes in flight rate...

What was the original supposition that lead to this discussion about "marginal cost"?  I think it's been a while, and I've forgotten.

It was suggested that it might be worthwhile to use SLS as a substitute for Delta IV Heavy to launch large DoD payloads, considering that SLS would already exist for unrelated reasons, whereas DIVH wouldn't:

http://forum.nasaspaceflight.com/index.php?topic=38021.msg1425851#msg1425851

The question about DIVH doesn't seem to turn exclusively or even primarily on the marginal cost question, but the marginal cost question was apparently contentious on its own.

There was an earlier discussion in another thread, sparked by an offhand comment I made in a post on a different subject:

http://forum.nasaspaceflight.com/index.php?topic=38171.msg1424057#msg1424057

It was off topic there, but it's not off topic here, so here it is.

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Is "marginal cost" something that will play into the discussion about the future of the SLS?  In other words, is a future NASA Administrator going to be called in front of Congress and asked what the "marginal cost" is of the SLS, and that their answer will determine whether an additional SLS is authorized?

Or are we talking about something that only accountants get excited about?

The marginal cost we've been discussing is the cost incurred by the U.S. Government in changing the SLS flight rate.  If you wanted to put a DoD payload on SLS, with sufficient lead time of course, this is what you'd pay to do that.  If you wanted to double the launch rate from one per year to two, this is what you'd pay every year to do that.  Exclusive of payload costs, of course...

This could easily come up in front of Congress, because unless someone's talking about cancelling the program outright, marginal cost is the only cost associated with SLS that actually affects overall budget allocations (how the money is distributed between agencies is a separate issue).

...of course, that's only technically true below the current maximum production rate.  Going above that is a bit different, because in addition to the marginal cost (which is higher because of the infrastructure delta), you also have the one-time capital cost of the upgrade...

EDIT: It's probably more likely that Congress would ask about the total cost of a plan, and the marginal cost of increasing the SLS flight rate to execute the plan would be rolled into the estimate, perhaps implicitly.  It's still important that anyone contemplating a use for SLS understand the difference between total cost and marginal cost, so as to properly forecast what the effect of a change will be.

Do we really need to up the SLS production rate beyond 2 a year?

Do we really need a space program at all?

Jupiter was supposed to fly six times per year, two J-130s for ISS runs and four J-246es for two Constellation-class lunar surface sorties (or two of each configuration; apparently J-130 could loft Orion+Altair to LEO if they did separate circ burns).  And the flight rate could easily increase if anything else wanted doing.

Now, we probably don't need SLS making milk runs to the ISS.  But I see no reason why a couple of heavy lunar landers per year (perhaps developed from existing upper stage technology, so as to save money vs. Altair) should be out of scope, except that Obama's "vision" seems to have sucked all the hope out of everybody.  Add depots (with tankers), and you've freed up a couple of launches, but you still have to go past two per year if you want to do literally anything else on top of your six-month moon base rotation.  Like, say, launch scientific probes to the outer planets, or large space telescopes, or BA-330s to cislunar space, or BA-2100s to LEO, or the notional giant black payloads that have been hinted about, or, y'know...  go to Mars.  Especially every two years...

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More SLS launches would equal less in space assembly.
There are trade-offs that negate that potential advantage.

Trade-offs?  Sure, though the big one is the mere existence of SLS and its budget line (again, marginal cost proves relevant).  Negate?  Not necessarily.  Remember, you're adding a lot of design and development, a lot of extra hardware and extra mass, and a lot of extra on-orbit operations, and the result may even end up less capable and/or less robust because of all the hardware overhead.

Parkinson and Hempsell (2003) claim that "space station acquisition costs are dominated by the level of modularization and in orbit assembly, to the extent that in a mixed launcher fleet it pays to use the largest launch system regardless of any impact on launch costs" (emphasis added).  This of course assumes that the HLV already exists, so development costs are excluded.  Mark Hempsell has backed off from this position somewhat, and as of 2011 (http://forum.nasaspaceflight.com/index.php?topic=24621.msg735577#msg735577) seems to have believed that the combination of inflatable structures and a successful Skylon makes the tradeoff with an HLV "finely balanced".

Now, a Mars mission is not a space station.  But plainly the in-space assembly question cannot be carelessly handwaved away.
Title: Re: SLS General Discussion Thread 2
Post by: Coastal Ron on 09/28/2015 11:10 PM
Going all commercial wouldn't work IMHO. You would run into capacity and volume issues that I have pointed out previously.

As I've mentioned previously, I don't see any capacity issues for the SLS.  Sure there would be a cost to expanding the current production capabilities, but it would be doable, and probably for a cost less than what this initial capacity cost.

For commercial launchers there are no capacity issues either.  I've heard the number 160 thrown around, and if that was over a period of 10 years that's only 16 flights per year, which would be 8/year if divided between two providers.  That's doable with the current ULA and SpaceX production capabilities, even with other customers in the mix.  And both ULA and SpaceX have stated they can expand their production capabilities if needed.  From my manufacturing operations perspective, this is a non-issue.

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A number of payloads as well as manned Orion launches wouldn't work on a Falcon Heavy or a Vulcan.

Already the Mars proposal has elements that could fly on existing launchers, and Orion could fly on the upcoming Falcon Heavy - which is planned to be operational before the SLS is.  Obviously something like ULA's Distributed Launch concept would need to be used, but that is a launch vehicle-independent technique that is needed for expanding humanity out into space anyways, so perfecting it sooner rather than later is good.

As to other payloads, we don't really know how we're going to land large amounts of mass on Mars yet, so we don't know if 8m diameter payloads are necessary.

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The best bet is to use commercial to supplement SLS.

I would simplify that even more.  Redundancy should be a priority, meaning the loss of any launch family should not stop our progress.
Title: Re: SLS General Discussion Thread 2
Post by: Endeavour_01 on 09/29/2015 12:28 AM
Do we really need to up the SLS production rate beyond 2 a year?

Do we really need a space program at all?

Now, we probably don't need SLS making milk runs to the ISS.  But I see no reason why a couple of heavy lunar landers per year (perhaps developed from existing upper stage technology, so as to save money vs. Altair) should be out of scope, except that Obama's "vision" seems to have sucked all the hope out of everybody.  Add depots (with tankers), and you've freed up a couple of launches, but you still have to go past two per year if you want to do literally anything else on top of your six-month moon base rotation.  Like, say, launch scientific probes to the outer planets, or large space telescopes, or BA-330s to cislunar space, or BA-2100s to LEO, or the notional giant black payloads that have been hinted about, or, y'know...  go to Mars.  Especially every two years...

Look I am all in favor of flying 3 or 4 SLS's a year. I just wanted to point out that we don't necessarily have to increase production more than 2 per year in order to achieve certain mission plans (EMC). I keep hearing the argument, "it can only launch twice a year so lets cancel it and yada yada yada." I just wanted to counter that argument. You could do a purely cislunar mission with a lunar space station and lunar lander with a two launch per year cadence. To do Moon, Mars, and elsewhere or a combination of them you need more than 2 SLS flights per year.
Title: Re: SLS General Discussion Thread 2
Post by: 93143 on 09/29/2015 12:58 AM
Fair enough.  It is certainly possible to do interesting missions under the current constraints.

I'm just a bit annoyed that they've baked in such an anemic maximum, or rather that they've been forced to do so by budget pressure and lack of vision.  It seems such a waste of potential to go to all the trouble to build an HLV and then barely use it.

...well, it's better than one flight every two years, as was the projection not so long ago...
Title: Re: SLS General Discussion Thread 2
Post by: MarcAlain on 09/30/2015 02:29 AM
I'd rather see a focus on landing on the Moon, practicing base building there, and developing a L2 station than trying to do a bare bones trip to Mars.
Title: Re: SLS General Discussion Thread 2
Post by: sdsds on 09/30/2015 04:12 AM
I'd rather see a focus on landing on the Moon, practicing base building there, and developing a L2 station than trying to do a bare bones trip to Mars.

Take heart! Sure NASA talks of Mars, and has a plan which will, "Keep Mars in view." But look at the capabilities of the system they're building. It produces one launch a year, sometimes bursting to two. And nothing they're building today is useful solely for Mars missions. In fact "all the wood" right now is behind the proving ground "arrow."

Only once there's substantial progress on a deep space habitat will it make sense to ask, "What sort of system for transport to the surface of a planetary body comes next?" If the time comes and the budget can support these amazing Mars missions, then sure let's go for it. But more realistically, you're likely to get your wish!
Title: Re: SLS General Discussion Thread 2
Post by: Hog on 09/30/2015 05:20 PM
1.  Someone said, somewhere here, that when facility to manufacture Saturn V 1st and 2nd stages were for 6 Saturn V's per year.  So, the facility can at least do 6.

2.  The VAB can process at least 4 at a time.  It has 4 bays.  They would have to build at least 4 platforms.   

 Also, there is not only one pad for SLS.
Clarification please.
Are you saying there is one pad, or more than 1 pad for SLS?
Title: Re: SLS General Discussion Thread 2
Post by: Mark S on 09/30/2015 08:59 PM
1.  Someone said, somewhere here, that when facility to manufacture Saturn V 1st and 2nd stages were for 6 Saturn V's per year.  So, the facility can at least do 6.

2.  The VAB can process at least 4 at a time.  It has 4 bays.  They would have to build at least 4 platforms.   

 Also, there is not only one pad for SLS.
Clarification please.
Are you saying there is one pad, or more than 1 pad for SLS?

I'm pretty sure that Jim meant "there is now only one pad for SLS", since NASA leased pad 39A to SpaceX. The implication is that SLS cannot have a higher launch rate e.g. Shuttle because of the limitation of a single SLS launch pad 39B.

However, SLS is not Shuttle and it will have a clean pad with no FSS or RSS. So it seems to me that the limitation would be in the number MLPs, not pads. If NASA needed to launch multiple SLSes in hurry, they just need more MLPs. Roll up, hook up, launch. At least, that's the theory. :) I'm sure the reality would be a non-trivial amount of time between launches, even with a clean pad.

Mark S.
Title: Re: SLS General Discussion Thread 2
Post by: spacenut on 09/30/2015 09:21 PM
So if they had two MLP's and used two bays to set up a couple of SLS's, they could what launch 1 a week?  If they had unlimited cores and boosters coming in.  So, it seems to me the bottleneck for launching more than two a year is production at McCloud facility.  Don't know about ATK production of boosters.  I understand once the steel boosters are gone, they will go to the Black Knights.  Now is seems they should have designed a clean sheet with reusable boosters and core, or at least a return pod with the engines. 
Title: Re: SLS General Discussion Thread 2
Post by: Jim on 09/30/2015 09:37 PM
So if they had two MLP's and used two bays to set up a couple of SLS's, they could what launch 1 a week? 

No, booster stacking takes longer than that.  Add in upper stage and payload and VAB time is much more than Shuttle. 
Title: Re: SLS General Discussion Thread 2
Post by: Coastal Ron on 09/30/2015 09:40 PM
So, it seems to me the bottleneck for launching more than two a year is production at McCloud facility.

Don't fall into the trap of thinking that just improving one "bottleneck" automatically means you can launch an SLS weekly.  NASA paid their contractors to build a production system based on a limited flight rate, because NASA does not have any visibility into the true need the future flight rate.  No one does until Congress approves the allocation of money to make it happen.

What that means is that money will be needed throughout the supply chain to increase production.  How much?  We in the public don't know, but on average it should be less per unit produced than the current rate.  And likely there is an upper end where new facilities and transportation systems will be needed.

Quote
Now is seems they should have designed a clean sheet with reusable boosters and core, or at least a return pod with the engines.

Reusable SLS 1st stage?  Are you serious?
Title: Re: SLS General Discussion Thread 2
Post by: Mark S on 10/01/2015 02:04 PM
So if they had two MLP's and used two bays to set up a couple of SLS's, they could what launch 1 a week? 

No, booster stacking takes longer than that.  Add in upper stage and payload and VAB time is much more than Shuttle.

Assume NASA has two high bays in the VAB for SLS stacking, and two MLPs to put them on. And it stacks two SLS vehicles complete with boosters, EUS, and payload/Orion. You now have two SLS ready to launch on their own mobile platforms sitting in the VAB, and a single clean pad to launch them from (39B).

Assuming just one CT, what would be the minimum interval of time between launching the two fully stacked and prepped SLS on the single pad 39B? My guess is certainly more than a week, but hopefully less than a month.

What would have to take place between the two launches? Clearly there would need to be a lot LH2 on hand. :) Does the LH2 tank hold enough for two launches? If not, how long would it take to top it off?

And I'm sure there's a lot of work to hook utilities, data, and piping up to the MLP once it is delivered to the clean pad.

Remember that this is just a thought exercise. Please be kind. :)

Mark S.
Title: Re: SLS General Discussion Thread 2
Post by: jongoff on 10/01/2015 11:04 PM
1.  Someone said, somewhere here, that when facility to manufacture Saturn V 1st and 2nd stages were for 6 Saturn V's per year.  So, the facility can at least do 6.

2.  The VAB can process at least 4 at a time.  It has 4 bays.  They would have to build at least 4 platforms.   

1.  Not true.  Space/volume does not determine capability.  The tooling does.  Anyways, it is a shared facility and there are other users

2.  See above. The 4 bays were never fully outfitted and even during shuttle, only two were outfitted.  Also, there is not only one pad for SLS.

Also, IIRC doesn't the quantity-distance rules on the SRBs mean they are only allowed to have two SLS vehicles in the VAB at one time, or am I misremembering that detail?

~Jon
Title: Re: SLS General Discussion Thread 2
Post by: TomH on 10/02/2015 03:39 PM
I'm pretty sure that Jim meant "there is now only one pad for SLS", since NASA leased pad 39A to SpaceX. The implication is that SLS cannot have a higher launch rate e.g. Shuttle because of the limitation of a single SLS launch pad 39B.

There is one pad and one ML. Original maps of Complex 39 show locations for 5 potential pads, but it is doubtful in the extreme that any more would ever be developed. Even if they wanted to, environmental impact reviews would most surely prevent it anyway.
Title: Re: SLS General Discussion Thread 2
Post by: Mark S on 10/02/2015 05:47 PM
I'm pretty sure that Jim meant "there is now only one pad for SLS", since NASA leased pad 39A to SpaceX. The implication is that SLS cannot have a higher launch rate e.g. Shuttle because of the limitation of a single SLS launch pad 39B.

There is one pad and one ML. Original maps of Complex 39 show locations for 5 potential pads, but it is doubtful in the extreme that any more would ever be developed. Even if they wanted to, environmental impact reviews would most surely prevent it anyway.

Wow, I didn't think it was that hard of a question. Or that the possibility of a second ML being built was so far out there. And I never said anything about building any more launch pads. I just wanted to know if making a clean pad was of any benefit whatsoever to possible future launch rates.

So now that we know that NASA will never build another ML or have more than one launch pad. How long will it take NASA to launch all of the SLS needed for one complete current Mars DRM mission, given one ML, one pad, and one VAB high bay. Have they gotten the number of launches below 10 yet?

Remember, we're on a Journey to Mars(TM)!!

Thanks.
Title: Re: SLS General Discussion Thread 2
Post by: Khadgars on 10/02/2015 06:30 PM
I'm pretty sure that Jim meant "there is now only one pad for SLS", since NASA leased pad 39A to SpaceX. The implication is that SLS cannot have a higher launch rate e.g. Shuttle because of the limitation of a single SLS launch pad 39B.

There is one pad and one ML. Original maps of Complex 39 show locations for 5 potential pads, but it is doubtful in the extreme that any more would ever be developed. Even if they wanted to, environmental impact reviews would most surely prevent it anyway.

Wow, I didn't think it was that hard of a question. Or that the possibility of a second ML being built was so far out there. And I never said anything about building any more launch pads. I just wanted to know if making a clean pad was of any benefit whatsoever to possible future launch rates.

So now that we know that NASA will never build another ML or have more than one launch pad. How long will it take NASA to launch all of the SLS needed for one complete current Mars DRM mission, given one ML, one pad, and one VAB high bay. Have they gotten the number of launches below 10 yet?

Remember, we're on a Journey to Mars(TM)!!

Thanks.

I thought the article pretty much spelled that out.
From the article.
Quote
Mars 2039:

Build up for the first human Mars mission would commence in 2033 with the launch of an SLS mission to deliver the TEI stage to Cis-lunar space.

This would be followed in 2034 by the launch of the first two Mars Surface Landers on two separate SLS missions.

The year 2035 would then see two more SLS missions, with the launches of the third and fourth Mars Surface Landers.

This would be followed in 2036 with the launch of the fifth and final Mars Surface Lander.

With the launch of the fifth lander, all pre-deployment payloads for the first human Mars mission will have been launched.

The year 2036 would then see the launch of the EOI stage before the 2037 launches of the MOI and TMI stages on two separate SLS launches.

In 2038, a crewed mission of Orion and SLS would bring a check out crew on a restock mission to the Mars Transit Habitat — which would have returned to Cis-lunar space in late 2035 from the human Phobos mission.

If those checkouts and restocks are successful, the first crew for Mars would then launch in 2039 to the Mars Transit Habitat before departing Cis-lunar space for Mars.

Assuming a nominal mission, a single SLS flight would be needed in 2042 to launch an Orion capsule to retrieve the first Mars crew and their cargo following their return to Cis-lunar space.

For the first human mission to Mars, SLS’s launch campaign will see it deliver 630.7t of mass to Cis-lunar space.
Title: Re: SLS General Discussion Thread 2
Post by: Mark S on 10/02/2015 06:45 PM
You're right, of course. NSF always has the full scoop.

Thanks.
Title: Re: SLS General Discussion Thread 2
Post by: TomH on 10/02/2015 08:20 PM
I'm pretty sure that Jim meant "there is now only one pad for SLS", since NASA leased pad 39A to SpaceX. The implication is that SLS cannot have a higher launch rate e.g. Shuttle because of the limitation of a single SLS launch pad 39B.

There is one pad and one ML. Original maps of Complex 39 show locations for 5 potential pads, but it is doubtful in the extreme that any more would ever be developed. Even if they wanted to, environmental impact reviews would most surely prevent it anyway.

Wow, I didn't think it was that hard of a question. Or that the possibility of a second ML being built was so far out there. And I never said anything about building any more launch pads. I just wanted to know if making a clean pad was of any benefit whatsoever to possible future launch rates.

Feeling a bit sensitive today? Where did all that come from?

Remember, we're on a Journey to Mars(TM)!!

No we're not. We're sending pork to particular states and districts that used to build STS parts. No money at all is allocated to do anything on Mars. And likely never will be.
Title: Re: SLS General Discussion Thread 2
Post by: Khadgars on 10/02/2015 08:29 PM
I'm pretty sure that Jim meant "there is now only one pad for SLS", since NASA leased pad 39A to SpaceX. The implication is that SLS cannot have a higher launch rate e.g. Shuttle because of the limitation of a single SLS launch pad 39B.

There is one pad and one ML. Original maps of Complex 39 show locations for 5 potential pads, but it is doubtful in the extreme that any more would ever be developed. Even if they wanted to, environmental impact reviews would most surely prevent it anyway.

Wow, I didn't think it was that hard of a question. Or that the possibility of a second ML being built was so far out there. And I never said anything about building any more launch pads. I just wanted to know if making a clean pad was of any benefit whatsoever to possible future launch rates.

Feeling a bit sensitive today? Where did all that come from?

Remember, we're on a Journey to Mars(TM)!!

No we're not. We're sending pork to particular states and districts that used to build STS parts. No money at all is allocated to do anything on Mars. And likely never will be.

I keep hearing that.  But one thing no one mentions is the $4 Billion ISS budget.

Once that program is done, the entire NASA HSF budget of $9 Billion would be enough to support a Phobos/Mars program with international support imo.
Title: Re: SLS General Discussion Thread 2
Post by: sdsds on 10/02/2015 08:41 PM
one thing no one mentions is the $4 Billion ISS budget. [...] Once that program is done, the entire NASA HSF budget of $9 Billion would be enough to support a Phobos/Mars program with international support imo.

Some aspects of ISS get mentioned a lot. In particular, commercial crew. It's a bit circuitous but commercial crew removes dependence on Russia, and thus enables replacing ISS with a new international LEO station in which Russia is not one of the partners. The perfect vehicle to launch that station (or at least the lion's share of its mass) is ... SLS!
Title: Re: SLS General Discussion Thread 2
Post by: spacenut on 10/02/2015 08:54 PM
When FH comes on line, two Bigelow 330 modules will be about the size of the ISS now, with only two FH launches, at about half the price of SLS.  With reusable rockets with SpaceX and engines with ULA, prices to launch will come down and SLS will become too expensive to launch except for very large payloads.  Even then Vulcan with ACES and solids could do probably 40 tons or more.  A 3 core Vulcan could match FH from Space X.  As reuse comes down, used rockets or engines will make cargo type payloads much cheaper.  SLS will only be able to deliver 105 tons to LEO and it won't be cheap.  Also with SEP tugs to move 40-50 ton payloads around, in orbit or L1 assembly for large spacecraft to Mars or the probes to the outer solar system can be done with the reusable rockets.  I predict SLS will be cancelled by the mid 2020's especially if SpaceX comes through with the reusable MCT.  SLS should have been made reusable, with fly back or land back boosters, a plug nozzle engine on the core to land back the core.  Then it would have been less expensive to operate being reusable. 
Title: Re: SLS General Discussion Thread 2
Post by: sdsds on 10/02/2015 09:10 PM
two Bigelow 330 modules will be about the size of the ISS now, with only two FH launches, at about half the price of SLS. [...] I predict SLS will be cancelled by the mid 2020's 

Yes, that might happen. By then we'll know so much more about SpaceX and Bigelow and what they can accomplish! Perhaps they will be able to work with ESA and JAXA on an international LEO station. It might be fun to discuss that on another thread.

The question that's relevant here is whether NASA could leverage its ISS experience with ESA and JAXA in a fairly straight-forward way to create an International Skylab, launched on SLS. I think they could!

Title: Re: SLS General Discussion Thread 2
Post by: RonM on 10/02/2015 09:16 PM
two Bigelow 330 modules will be about the size of the ISS now, with only two FH launches, at about half the price of SLS. [...] I predict SLS will be cancelled by the mid 2020's 

Yes, that might happen. By then we'll know so much more about SpaceX and Bigelow and what they can accomplish! Perhaps they will be able to work with ESA and JAXA on an international LEO station. It might be fun to discuss that on another thread.

The question that's relevant here is whether NASA could leverage its ISS experience with ESA and JAXA in a fairly straight-forward way to create an International Skylab, launched on SLS. I think they could!

NASA has stated they won't build another LEO space station. SLS could be used for a cis-lunar station. Perhaps a gateway station at EML-2.

ESA, JAXA, and Russia could work with China on the Chinese space station. Bigelow or someone else could build a commercial space station. Obviously, SLS would not be a part of that.
Title: Re: SLS General Discussion Thread 2
Post by: 93143 on 10/02/2015 09:50 PM
Bigelow or someone else could build a commercial space station. Obviously, SLS would not be a part of that.

I don't know about that.  As far as I know, it's got a decent shot at being the only rocket available capable of lofting a BA-2100...  not that you'd necessarily want to start with something of that scale, but the fact remains that Bigelow has advertised the thing...
Title: Re: SLS General Discussion Thread 2
Post by: robertross on 10/02/2015 10:48 PM
1.  Someone said, somewhere here, that when facility to manufacture Saturn V 1st and 2nd stages were for 6 Saturn V's per year.  So, the facility can at least do 6.

2.  The VAB can process at least 4 at a time.  It has 4 bays.  They would have to build at least 4 platforms.   

1.  Not true.  Space/volume does not determine capability.  The tooling does.  Anyways, it is a shared facility and there are other users

2.  See above. The 4 bays were never fully outfitted and even during shuttle, only two were outfitted.  Also, there is not only one pad for SLS.

Also, IIRC doesn't the quantity-distance rules on the SRBs mean they are only allowed to have two SLS vehicles in the VAB at one time, or am I misremembering that detail?

~Jon

Somewhere on L2 there was nice overview of the VAB facility and the maximum number of SRB segments allowed in there. I thought it was 10 segments total.
Title: Re: SLS General Discussion Thread 2
Post by: Mark S on 10/03/2015 02:11 AM
Feeling a bit sensitive today? Where did all that come from?

Ha! You should have seen my post before I self-censored it. LOL.

So, now the consensus is that there will only be one ML, thus the minimum time between SLS launches will be however long it takes to stack one up in the VAB. Does anyone have an idea about how long that may be?

Which then brings us back to the Mars mission proposals mentioned in the recent article, as Khadgars kindly pointed out. One proposal has two SLS launches of equipment to Mars in 2034, 2035, and 2036. (Five landers and the EOI stage.)

I'm no orbital expert, but I thought that Mars missions were normally spaced out every two years due to the relationship between Earth's and Mars' orbits. Is it possible to launch large payloads to Mars in the "off" years?

And, going back to the minimum time between SLS launches, how large is the launch window for Mars missions in the "on" years? Is it possible that a delay in the stacking of the second SLS in a sequence would cause it to miss the launch window?

Thanks.
Title: Re: SLS General Discussion Thread 2
Post by: jongoff on 10/03/2015 02:59 AM
1.  Someone said, somewhere here, that when facility to manufacture Saturn V 1st and 2nd stages were for 6 Saturn V's per year.  So, the facility can at least do 6.

2.  The VAB can process at least 4 at a time.  It has 4 bays.  They would have to build at least 4 platforms.   

1.  Not true.  Space/volume does not determine capability.  The tooling does.  Anyways, it is a shared facility and there are other users

2.  See above. The 4 bays were never fully outfitted and even during shuttle, only two were outfitted.  Also, there is not only one pad for SLS.

Also, IIRC doesn't the quantity-distance rules on the SRBs mean they are only allowed to have two SLS vehicles in the VAB at one time, or am I misremembering that detail?

~Jon

Somewhere on L2 there was nice overview of the VAB facility and the maximum number of SRB segments allowed in there. I thought it was 10 segments total.

Ok, so I'm not misremembering things. So that would prevent having more than two SLS's in the building at any given time. One of the joys of big SRBs...

~Jon
Title: Re: SLS General Discussion Thread 2
Post by: Coastal Ron on 10/03/2015 03:00 AM
NASA has stated they won't build another LEO space station.

Gerstenmaier said just this year:

At some point this space station will wear out and there needs to be a follow-on space station,”...“What we’re hoping for is that the private sector picks that up.

But based on comments NASA has made about the importance of the ISS for preparing for Mars, I'd say they are talking about an LEO commercial station.

Quote
SLS could be used for a cis-lunar station. Perhaps a gateway station at EML-2.

You have to consider what the goal of a cis-lunar station would be, within the context of NASA's current direction.  If it's to continue the work the ISS was not able to complete in support of going to Mars, then putting it 1,000X further away is not going to be very economical.

As to possible commercial stations, NASA did a study (referenced in this NSF article (http://www.nasaspaceflight.com/2014/02/affordable-habitats-more-buck-rogers-less-money-bigelow/)) that said a notional Bigelow BA-2100 could fly on a Falcon Heavy.  And if it is a commercial station, then cost will be a big factor for whoever is building it.  Certainly an SLS could lift it, but whether it makes sense from a cost standpoint is another matter.

Quote
ESA, JAXA, and Russia could work with China on the Chinese space station. Bigelow or someone else could build a commercial space station. Obviously, SLS would not be a part of that.

All of those countries have challenging economies right now, with some more than others (i.e. Russia).  I think China will proceed with their station plans for LEO, but I think it will be a while until everyone else has the money to pursue another expensive space endeavor.
Title: Re: SLS General Discussion Thread 2
Post by: 93143 on 10/03/2015 03:25 AM
As to possible commercial stations, NASA did a study (referenced in this NSF article (http://www.nasaspaceflight.com/2014/02/affordable-habitats-more-buck-rogers-less-money-bigelow/)) that said a notional Bigelow BA-2100 could fly on a Falcon Heavy.

That's not exactly what it said:

"Although the Olympus module is being offered as a potential payload for SLS, the Gate 1 Report indicates that it could possibly also be launched on a Falcon Heavy."

As I understand it, there is/was some doubt as to whether the mass will end up low enough.  Certainly the earlier numbers were nowhere near what Falcon Heavy could manage, and scaling a BA-330 by the 2/3 power of the volume difference ends up close to 70 tonnes.  However, the reports are not public, and I can't find the relevant portion in L2.

More to the point, it seems SLS was the LV of choice when that report was submitted (it wasn't a NASA study as such; it was a submission by Bigelow under a Space Act Agreement).
Title: Re: SLS General Discussion Thread 2
Post by: Coastal Ron on 10/03/2015 03:53 AM
As I understand it, there is/was some doubt as to whether the mass will end up low enough.

Keep in mind that the BA-2100 is a concept, not reality.  It can be whatever Bigelow wants it to be - SLS sized, Falcon Heavy sized, etc.  It will depend on what the requirements are, and so far there are no firm requirements.  It certainly is not part of the current Mars plan, and that plan consumes all of NASA's forecasted budget for two decades.
Title: Re: SLS General Discussion Thread 2
Post by: 93143 on 10/03/2015 04:13 AM
You do realize the name actually includes its volume in cubic metres, right?

It is, as you say, a concept, and it's already been thought of.  It's roughly SLS-sized.  It might fit on Falcon Heavy; that would be great.

EDIT:  After double-checking a bit, it seems my memory was correct; from what we know, BA-2100 is not close to being light enough for the 53-tonne Falcon Heavy to lift it.  Some sort of upgrade would be required.
Title: Re: SLS General Discussion Thread 2
Post by: Endeavour_01 on 10/03/2015 04:14 AM
\Which then brings us back to the Mars mission proposals mentioned in the recent article, as Khadgars kindly pointed out. One proposal has two SLS launches of equipment to Mars in 2034, 2035, and 2036. (Five landers and the EOI stage.)

I'm no orbital expert, but I thought that Mars missions were normally spaced out every two years due to the relationship between Earth's and Mars' orbits. Is it possible to launch large payloads to Mars in the "off" years?

The once every two years is for direct TMI using chemical propulsion. With SEP you shouldn't have the time constraint.

When FH comes on line, two Bigelow 330 modules will be about the size of the ISS now, with only two FH launches, at about half the price of SLS. 

Launching payloads to LEO smaller than 50 mt should go to FH or Vulcan whenever possible. Your example of launching a new LEO commercial space station is a great idea. In my view SLS and commercial vehicles should complement each other. SLS handles big payloads (above 50 mt) to LEO and the BLEO crew and cargo while FH and Vulcan handle smaller missions to LEO and BEO (say launching a Dragon as a resupply craft to a lunar space station).
Title: Re: SLS General Discussion Thread 2
Post by: a_langwich on 10/03/2015 04:15 AM

I keep hearing that.  But one thing no one mentions is the $4 Billion ISS budget.

Once that program is done, the entire NASA HSF budget of $9 Billion would be enough to support a Phobos/Mars program with international support imo.

That's funny, because I keep hearing THAT, once we kill off ISS that's $4 billion to spend on wonderful things.  Let's take a look, shall we?

https://oig.nasa.gov/audits/reports/FY15/IG-15-021.pdf

Table 1, you can follow along...

ISS budget request for FY 2016 = 3.106 billion. 
Subdivided into
  -- commercial crew and cargo  = 1.606 billion
  -- operations and maintenance = 1.106 billion
  -- research = 394 million

You can dig through the OIG audit of some of the contracts for the different areas, and ask yourself:  is this capability going to disappear, or is it likely going to be needed in some other form going forward? 

For example, commercial crew and commercial cargo are arguably driving some of the biggest transformations in the launch industry.  Sure, after some future president knifes the ISS, those won't be needed...but isn't it reasonable to assume NASA will still want some crew and cargo transported to some other LEO destination, even if it were a commercial station?  As far as I can see, the need for LEO operations will never cease as long as humans are spacefaring, it's just a matter of how to partition it into commercial and government-led.

Do you see Bigelow stepping up to a rigorous permanently manned mission control for a permanently manned station, capable of safely overseeing station operations, conducting research or collecting data over year-long time scales?  That's probably what NASA would need, if they were going to be a customer.  I don't see that, but to be fair they may develop quite a bit if they get going.  But that's another sticking point, right now it looks like Bigelow has given up on a non-governmental marketplace, and so in addition to commercial crew and commercial cargo, they would need a commercial station funding contract. 

Or what about the only manned Mission Control Center, the only manned mission planning office, or the Neutral Buoyancy Lab, or the spacesuit design and testing office?  Isn't it likely they will be required in whatever future manned endeavors NASA undertakes?

Rather than eyeing the ISS budget as free extra money, it's more realistic to assume that ISS Operations will probably transition to BEO Operations, and there will likely still be a fair amount of NASA-supported LEO activity.  Supported, I should say, not as a jobs program, but because the needs/benefits outweigh the costs.

Even the Boeing contract to support ISS will have a very similar counterpart in an future contracts to support SLS, Orion, and the various habitation and exploration modules.

Killing ISS then, in my opinion, should* free up very little to nothing to help DEVELOP new modules or systems, but it might get converted to the budget slice for operations and management of SLS and BEO missions.

*I say SHOULD because of course in some fantasy world you could shut the doors at JSFC, and throw away the manned mission control capability, and the spacesuit expertise, and the planning and Neutral Buoyancy Center testing, and so on, and use nearly the full $3 billion for development.  But it seems fairly clear this would be a colossal blunder--sacrificing capabilities that will be needed in the near future, and expensive-to-impossible to re-constitute at the same expertise level--and politically impossible as well.
Title: Re: SLS General Discussion Thread 2
Post by: sdsds on 10/03/2015 04:24 AM
NASA has stated they won't build another LEO space station.

I agree that powerful people (including I think NASA Administrator Charlie Bolden) say that, and it reflects the view of the President of the United States. But in 2020 I do not believe Charlie Bolden will be NASA Administrator, and I am 100% certain President Obama will no longer occupy the Oval Office!
Title: Re: SLS General Discussion Thread 2
Post by: A_M_Swallow on 10/03/2015 05:49 AM

NASA has stated they won't build another LEO space station. SLS could be used for a cis-lunar station. Perhaps a gateway station at EML-2.

ESA, JAXA, and Russia could work with China on the Chinese space station. Bigelow or someone else could build a commercial space station. Obviously, SLS would not be a part of that.

NASA may be willing to rent time on a LEO spacestation. If it rents large amounts of time NASA may be able to convince Congress to buy/lease the spacestation. Although the politicians may want to get involved with the negotiations.
Title: Re: SLS General Discussion Thread 2
Post by: Jim on 10/03/2015 12:02 PM
NASA has stated they won't build another LEO space station.

I agree that powerful people (including I think NASA Administrator Charlie Bolden) say that, and it reflects the view of the President of the United States. But in 2020 I do not believe Charlie Bolden will be NASA Administrator, and I am 100% certain President Obama will no longer occupy the Oval Office!

It reflects the view of many at NASA
Title: Re: SLS General Discussion Thread 2
Post by: MP99 on 10/03/2015 01:33 PM
Also, IIRC doesn't the quantity-distance rules on the SRBs mean they are only allowed to have two SLS vehicles in the VAB at one time, or am I misremembering that detail?

~Jon

Somewhere on L2 there was nice overview of the VAB facility and the maximum number of SRB segments allowed in there. I thought it was 10 segments total.

Ok, so I'm not misremembering things. So that would prevent having more than two SLS's in the building at any given time. One of the joys of big SRBs...

~Jon

Each SLS is 10 segments. ;-)

Cheers, Martin

PS am I wrong in vaguely remembering 16 segments (two complete Shuttles) back in the day?
Title: Re: SLS General Discussion Thread 2
Post by: Coastal Ron on 10/03/2015 02:57 PM
EDIT:  After double-checking a bit, it seems my memory was correct; from what we know, BA-2100 is not close to being light enough for the 53-tonne Falcon Heavy to lift it.  Some sort of upgrade would be required.

Well talk with Bigelow about that, but if the moniker "BA-2100" is what bothers you, change the name to BA-2000, or BA-1782.  Remember it doesn't have a firm requirement - it's notional.
Title: Re: SLS General Discussion Thread 2
Post by: oldAtlas_Eguy on 10/03/2015 03:51 PM
EDIT:  After double-checking a bit, it seems my memory was correct; from what we know, BA-2100 is not close to being light enough for the 53-tonne Falcon Heavy to lift it.  Some sort of upgrade would be required.

Well talk with Bigelow about that, but if the moniker "BA-2100" is what bothers you, change the name to BA-2000, or BA-1782.  Remember it doesn't have a firm requirement - it's notional.
It is speculated that by 2024 SpaceX would have its BFR flying but maybe not the MCT so they could use that vehicle with an interim expendable US to launch SLS sized cargo (15m diameter and 100mt+ weight payloads).

But a BA-2100 may not be what NASA may use for a second generation station. NASA likes proven tech for use with HSF. BA-330s would have collected a few years of operational experience by then so a station based on 3 or 6 of those would be sufficient. If they pack them with equipment and only have 3 crew for each module a 6 BA-330 station would be a crew size of 18 three times the current crew size. That would equate to 12 cargo flights per year and 8 crew flights (3-6 crew each flight) to service the station. US budget per year in cargo and crew = $1.5B + $1.2B for the module(lease or operational support and other NASA operational costs) for a total yearly budget of $2.7B. NASA could not afford anything bigger. Using the CRS and CC capabilities that would be available at the end of life of the ISS in 2024.

There are many options other than using the SLS for a follow on commercial ISS that do not require either the SLS or anything other than existing or close to existing vehicles (CC and FH in 2 years or less [2017], SLS could be considered in this list since first flight is only a year latter in 2018).
Title: Re: SLS General Discussion Thread 2
Post by: notsorandom on 10/03/2015 07:38 PM
Feeling a bit sensitive today? Where did all that come from?

Ha! You should have seen my post before I self-censored it. LOL.

So, now the consensus is that there will only be one ML, thus the minimum time between SLS launches will be however long it takes to stack one up in the VAB. Does anyone have an idea about how long that may be?

Which then brings us back to the Mars mission proposals mentioned in the recent article, as Khadgars kindly pointed out. One proposal has two SLS launches of equipment to Mars in 2034, 2035, and 2036. (Five landers and the EOI stage.)

I'm no orbital expert, but I thought that Mars missions were normally spaced out every two years due to the relationship between Earth's and Mars' orbits. Is it possible to launch large payloads to Mars in the "off" years?

And, going back to the minimum time between SLS launches, how large is the launch window for Mars missions in the "on" years? Is it possible that a delay in the stacking of the second SLS in a sequence would cause it to miss the launch window?

Thanks.
You are correct that the window opens every two years. There can be up to a few months where a launch can make use of it. However we are likely to see any Mars bound depart from LDRO or L2. Over the previous two years the hardware would have been positioned there and assembled. The last launch necessary would likely be the crew. A couple weeks margin could be included in making the Mars window by having the crew launch before the craft needed to leave for Mars. SEP could open the window up a bit more too. Srubs will happen but the planners will account for that and draw the schedules up so that things are not so rushed before the window closes.
Title: Re: SLS General Discussion Thread 2
Post by: sdsds on 10/03/2015 09:11 PM
NASA has stated they won't build another LEO space station.

I agree that powerful people [...] say that

It reflects the view of many at NASA

I believe that. Let's assume it reflects the views of every technically astute person at NASA. That still tells us almost nothing about the views of the powerful decision makers. ;)

(Note: I don't want NASA to invest in another LEO station. Like so many others I want a cis-lunar station. But I try not to confuse what I want with what I think is likely!)

As regards space stations, like with launch systems, NASA will comply with a law passed by Congress and signed by the President. Those decision makers consider things like the actions of other space agencies. With high probability, Russia will continuously keep a cosmonaut in space after ISS is decommissioned. Congress will want an astronaut to be continuously  in space as well. But nothing supporting that goal will be accomplished until it is almost too late. Then Boeing will offer to use SLS infrastructure at Michoud to manufacture a Skylab II. For those lobbyists, it's going to be almost a "slam dunk."

(Again note: If a United States based commercial station were already operating in LEO, we can hope NASA would use that to house its astronauts. Again though, let's avoid confusing our hopes with our predictions.)

It is speculated that by 2024 SpaceX would have its BFR flying but maybe not the MCT so they could use that vehicle with an interim expendable US to launch SLS sized cargo (15m diameter and 100mt+ weight payloads).

It's all speculation, but I doubt it helps predict the future to discuss an interim upper stage that hasn't been mentioned by the company claiming it will one day make the boost stage! A Bigelow station launched on FH would be quite plausible if there were a buyer for it that wanted to attempt to operate it at a profit. Paint me dubious about that last part, though.
Title: Re: SLS General Discussion Thread 2
Post by: 93143 on 10/03/2015 10:15 PM
EDIT:  After double-checking a bit, it seems my memory was correct; from what we know, BA-2100 is not close to being light enough for the 53-tonne Falcon Heavy to lift it.  Some sort of upgrade would be required.

Well talk with Bigelow about that, but if the moniker "BA-2100" is what bothers you, change the name to BA-2000, or BA-1782.  Remember it doesn't have a firm requirement - it's notional.

This whole discussion is notional, raised in answer to another poster's "obviously".  You're fighting a straw man here.
Title: Re: SLS General Discussion Thread 2
Post by: Proponent on 10/04/2015 10:50 AM
To exactly which document do you refer?  If to "ESD Integration; Budget Availability Scenarios" dated 19 August 2011 (attached to this post (http://forum.nasaspaceflight.com/index.php?topic=19892.msg811814#msg811814)), where does the statement appear?

Right below every sand chart, it says the following:

FY11:  21st CGS = CxP GO; MPCV = CxP Orion + EVA + MO; SLS =Ares I FS (Booster / Avionics), Ares I J-2X (US Engine), SSP SSME (Core Engine), SSP ET (Core Stage), Ares I PM / VI / S&MA / FITO (Prog Integ)

I may have overstated the clarity of the statement somewhat; how would you interpret this?

The notation below each sand chart looks to me like a broad-brush description of the hardware elements.  We can't take it too literally, though.  For example, while SLS's core stage superficially looks just like a Space Shuttle ET, it is in fact quite different, if for no other reason than the very different loads it bears.

Booz Allen Hamilton produced a contemporaneous critique (summary attached, for those who may not have seen it earlier) which described the cost savings NASA assumed for Orion/SLS as poorly justified.  Regardless of whether the criticism was correct, it does show that the ESD budget scenarios assumed future cost savings and were not based solely on Shuttle/Ares costs.
Title: Re: SLS General Discussion Thread 2
Post by: 93143 on 10/07/2015 02:33 AM
For example, while SLS's core stage superficially looks just like a Space Shuttle ET, it is in fact quite different, if for no other reason than the very different loads it bears.

As an aerospace engineer who's been following the SD-HLV saga in some detail since 2007, I'm not quite sure how to respond to this.

I'm not proposing that they copied total costs for the referenced elements exactly; I would assume they used more detailed data as a basis for their estimates, taking the necessary changes into account.

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Booz Allen Hamilton produced a contemporaneous critique (summary attached, for those who may not have seen it earlier) which described the cost savings NASA assumed for Orion/SLS as poorly justified.

Poorly justified in the sense that NASA did not provide sufficient rationale to BAH for the savings they incorporated into the estimates, not in the sense that the savings were unlikely to be realized.  According to people who read it, the actual report was clearer about this distinction than the executive summary.

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Regardless of whether the criticism was correct, it does show that the ESD budget scenarios assumed future cost savings and were not based solely on Shuttle/Ares costs.

Note that the ESD Integration document and the BAH report summary you attached are dated the same day.  Note also that the BAH report talks about the cost estimation cycle that produced the estimates they were critiquing having wrapped up in June of that year.  Case #1 in the ESD Integration document is labeled "6/27/11 ESD Preliminary Cost Estimate"; the others are not.  In other words, what BAH was analyzing was, at most, specifically Case #1.  (I'm not certain we can assume even that, as BAH makes no mention of ESD Integration, instead referring to estimates generated independently by the SLS, MPCV, and 21CGS programs.)

I have already complained about how Case #1 seems to make unexplained assumptions about cost savings that allow it to actually fly missions during Block 2 development with an annual budget for SLS + ground systems of less than $2B in then-year dollars (the 2025 budget for those elements is about $1.3B in 2011 dollars), despite the fact that from Cases #3 and #4 it looks like the basic carrying costs are higher than that.

Case #4, the one I used for my analysis, looks a bit different.  At one flight per year, the 2025 budget for SLS + ground systems is $2.17B in 2009 dollars, compared with $2.06B in 2009 dollars for J-246 at the same flight rate.  As far as fixed costs are concerned, it seems to me that the only major difference between J-246 and SLS is the upper stage; SLS in that document uses a big J-2X-based second stage instead of an RL-10-based EDS.  (I wouldn't expect the DCSS to add much fixed cost, since SLS in this scenario represents a definite minority of its flights.)  The marginal cost of the first flight every year would also be somewhat higher (particularly since it includes two upper stages), but not by a vast amount (for reference, the original ICPS contract had options for two additional flight units, totaling $132M).  And I believe DIRECT's MO was to assume traditional contracting and then pack their numbers with margin (though I'm not sure how much would have been added to running costs as they are easier to predict than development costs).  Unless DIRECT's numbers excluded ground systems ($400M in 2009 dollars), I don't see "large" cost savings assumed here.

Either way, the presence of the element enumeration under Case #1's sand chart does indicate that it probably doesn't mean what I took it to mean.  Good catch.  (This should have been evident to me from Case #1's budget numbers; I'm not sure why I maintained otherwise in the first place...)

Perhaps this is why the document was never officially released.  It is a presentation, after all; perhaps it works better with a presenter available to explain the assumptions...
Title: Re: SLS General Discussion Thread 2
Post by: Proponent on 10/13/2015 11:37 AM
Thanks to BAH, we know that NASA built to-be-realized cost efficiencies into at least some of its scenarios.  There is a theoretical possibility that NASA applied those efficiencies only to Case 1 and not to other cases, but that's rather unlikely and would be positively disingenuous.  No justification has yet been presented for "the ESD Integration estimates were based directly on Shuttle and Ares."

You infer that inflation has been built into ESD's estimates.  How do you do that?  With budgets generally flat-lining, except for an explicit in-space-elements "wedge" in later years, it looks to me like everything is priced in FY 2012 dollars.  "RY" might mean "real": I suppose to people who spend their workdays with terms like "FY", "CY" and "TY, " a construction like "RY" might seem reasonable.
Title: Re: SLS General Discussion Thread 2
Post by: spacenut on 10/13/2015 03:50 PM
If they are going to build a station, I agree it should be at L1 or L2.  I also wish they would build a rotating station at least with moon gravity.  I would really like them to build one based on Mars gravity, to test long term effects of Martian gravity on humans.  The L point station should also be modular enough to have replacements periodically for continuous operations.  It should also be able to expand into a fuel depot for Mars transits, and a warehouse type depot for Mars cargo departures. 

If it is a LEO station, it should at least be a fuel depot with not only LOX, but liquid methane, and argon or xenon for SEP tug refueling.  It could be manned continuously to monitor the fuels, and make maybe have robotic arms for helping SEP tugs refuel, or various vehicles to dock and refuel for out flights.  It could be a holdover for astronauts going to and from the Moon, an L station or Mars.  If they are going to the moon, they would have time during refueling, to exercise at the station or relax.  Cramped trips to the moon and back, it would be a break.  Eventually reusable moon transports could fly between the LEO refueling station, and an L station.  Then there could be reusable moon landers transporting between an L station and the moon's surface. 

All this can be future planned 100 ton launches from the SLS, to minimize in space assembly.  Smaller components could be launched using existing launchers, FH, and Vulcan.  Until SpaceX gets the BFR going. 
Title: Re: SLS General Discussion Thread 2
Post by: Coastal Ron on 10/14/2015 12:10 AM
If they are going to build a station, I agree it should be at L1 or L2.  I also wish they would build a rotating station at least with moon gravity.  I would really like them to build one based on Mars gravity, to test long term effects of Martian gravity on humans.

FYI, here are two threads that are more relevant for space stations:

Space Policy Discussion / Re: Space Stations after 2024 (http://forum.nasaspaceflight.com/index.php?topic=38612.0)

Advanced Concepts / Re: Realistic, near-term, rotating Space Station (http://forum.nasaspaceflight.com/index.php?topic=34036.0)

Quote
The L point station should also be modular enough to have replacements periodically for continuous operations.  It should also be able to expand into a fuel depot for Mars transits, and a warehouse type depot for Mars cargo departures.

Using Earth analogies, we don't combine hotels with gas stations, for a number of reasons, but even in space I'm not sure there would be enough synergy or need to combine them.

Quote
All this can be future planned 100 ton launches from the SLS, to minimize in space assembly.  Smaller components could be launched using existing launchers, FH, and Vulcan.  Until SpaceX gets the BFR going.

I'm not aware of any design for a rotating station that requires 100 ton modular components (i.e. SLS), or even 50 ton components (i.e. FH).  And using Earth analogies, we build the largest buildings in the world using the same sized semi-trailer trucks that we use for much building small houses, so I think $/kg will be the more important metric for determining which type of transportation is used, not size.
Title: Re: SLS General Discussion Thread 2
Post by: 93143 on 10/14/2015 06:40 AM
No justification has yet been presented for "the ESD Integration estimates were based directly on Shuttle and Ares."

I already acknowledged that the estimate sourcing probably wasn't as direct as I initially thought.  Actually, it seems I was more careful last time I discussed this, but this time I got overzealous and misinterpreted my memory of the discussion...  Sorry about that.

Quote
Thanks to BAH, we know that NASA built to-be-realized cost efficiencies into at least some of its scenarios.

That's assuming the estimate they were reviewing was actually the same one as in the document, which seems reasonable but is not yet solidly established as far as I am aware.

Quote
There is a theoretical possibility that NASA applied those efficiencies only to Case 1 and not to other cases, but that's rather unlikely and would be positively disingenuous.

Unless the bulk of these "efficiencies" involved nerfing the infrastructure and similar measures, as a desperation move to force the annual cost to fit under the budget bogey, rather than technological and contracting improvements.  This does not seem inconsistent with what BAH say in the report, or with the contents of the ESD Integration document itself.

Also, the cost estimators would have been working with BAH prior to the ESD Integration presentation on August 19, so they might have reacted to early feedback by producing additional estimates that relaxed some of the efficiency measures to fill out a more reasonable budget.  It's hard to tell without the verbal presentation (and presumably question period) that would have accompanied the slides at NASA - this was not, after all, an official release...

...

As I explained above, while there may be a modest amount of efficiency gain built into Case #4, it matches J-246 closely enough that I doubt anything radical was present in the numbers.  (BAH didn't specify what exactly they meant by "large"...)  Also keep in mind that this document predates all the reports of stuff that's actually been done, some of which does seem to qualify as radical...

There's a fairly small marginal cost difference evident between #4a and #4b, which makes the huge jump from Case #1 look outright suspicious; hence my assumption that the latter contained additional measures.  However, it occurs to me that it might be somewhat explicable; DIRECT budgeted several hundred million dollars a year in JUS fixed costs, so the lack of a large upper stage might explain most of the difference.  It does not, however, explain how they managed to fit "Competitive Booster" in by 2023...  maybe that's what BAH was complaining about...

Quote
You infer that inflation has been built into ESD's estimates.  How do you do that?  With budgets generally flat-lining, except for an explicit in-space-elements "wedge" in later years, it looks to me like everything is priced in FY 2012 dollars.

Look at what happens in the Senate cases once development ends.  There's a clear inflation in the ops budget lines year-to-year, and it basically matches the 2011 NASA New Start Inflation Index out-year value of 2.6%.

Besides, BAH states that inflation was incorporated into all three program estimates, though MPCV used outdated tables.

Quote
"RY" might mean "real": I suppose to people who spend their workdays with terms like "FY", "CY" and "TY, " a construction like "RY" might seem reasonable.

I looked it up.  It's "real year" dollars, which at NASA means "then year", ie: inflated, dollars.  This is apparently different from how some other organizations use "real year"...
Title: Re: SLS General Discussion Thread 2
Post by: 93143 on 10/14/2015 06:44 AM
I'm not aware of any design for a rotating station that requires 100 ton modular components (i.e. SLS), or even 50 ton components (i.e. FH).

Those are LEO masses.  For an L-point station you'd be looking at much smaller units, unless you postulate additional propulsion technologies (depots, large electric tugs).

Quote
And using Earth analogies, we build the largest buildings in the world using the same sized semi-trailer trucks that we use for much building small houses, so I think $/kg will be the more important metric for determining which type of transportation is used, not size.

http://www.jbis.org.uk/paper.php?p=2003.56.362
Title: Re: SLS General Discussion Thread 2
Post by: Coastal Ron on 10/14/2015 02:37 PM
I'm not aware of any design for a rotating station that requires 100 ton modular components (i.e. SLS), or even 50 ton components (i.e. FH).

Those are LEO masses.  For an L-point station you'd be looking at much smaller units, unless you postulate additional propulsion technologies (depots, large electric tugs).

If we're moving construction mass beyond LEO, then using SEP tugs or some other form of more efficient transportation would be used - we don't have to be constrained by the limitations of an upper stage.

Quote
Quote
And using Earth analogies, we build the largest buildings in the world using the same sized semi-trailer trucks that we use for much building small houses, so I think $/kg will be the more important metric for determining which type of transportation is used, not size.

http://www.jbis.org.uk/paper.php?p=2003.56.362

I'm not paying money for some 12 year old random study to try and figure out whether you have a point or not.
Title: Re: SLS General Discussion Thread 2
Post by: oldAtlas_Eguy on 10/14/2015 03:16 PM
I'm not aware of any design for a rotating station that requires 100 ton modular components (i.e. SLS), or even 50 ton components (i.e. FH).

Those are LEO masses.  For an L-point station you'd be looking at much smaller units, unless you postulate additional propulsion technologies (depots, large electric tugs).

If we're moving construction mass beyond LEO, then using SEP tugs or some other form of more efficient transportation would be used - we don't have to be constrained by the limitations of an upper stage.

Quote
Quote
And using Earth analogies, we build the largest buildings in the world using the same sized semi-trailer trucks that we use for much building small houses, so I think $/kg will be the more important metric for determining which type of transportation is used, not size.

http://www.jbis.org.uk/paper.php?p=2003.56.362

I'm not paying money for some 12 year old random study to try and figure out whether you have a point or not.
The point is true but only for the case where the number of total modules flown on the larger booster is less than a factor of 3 than the number of unique module designs. This holds for using a comparison of FHR and SLS where <40mt vs 100mt and a price difference factor for launch of 5.3. The cost of design of a module does not vary due to its size unless you get to very small building elements vs complete large modules. But manufacturing costs do vary based on module size. So for an ISS like station using SLS would be about 50% cheaper than using FHR to put all the same capability up in larger modules than using smaller modules with a smaller booster.

But for a much larger station whose factor of total modules to unique modules is 5 or 10 then using the smaller much cheaper LV gives a savings of 18% to 35% over using larger modules and the more expensive larger booster.

The point is that the economics models have assumptions and that your overall station design can drive one method of launch to be significantly cheaper overall than another. You would have to specify how you would design the station the, number of unique systems and their total weight per system, if the systems can be in smaller units but just more of them or if the units cannot be shrunk and have to be divided into sub-units, and if there are required redundancies involved for the systems or not , etc.

There is no way to definitively make the statement that one launch method will decrease your total station cost vs another unless you have some sort of preliminary design for the systems to be used and all the capabilities to be incorporated. Then you can model out the design economically to determine which direction to go small cheap $/kg launcher vs larger high cost $/kg launcher (we are talking about a factor of grater than 2 in payload size between launchers).
Title: Re: SLS General Discussion Thread 2
Post by: Zed_Noir on 10/14/2015 05:04 PM
@oldAtlas_Eguy you do realize that a SLS that can put 100mt in LEO is a Block 2 variant. We only have the Block-1 and maybe the Block-1B available for the foreseeable future. I am guessing the SLS can get roughly 50 or 60 mt up to LEO with a non-Block-2 variant.
Title: Re: SLS General Discussion Thread 2
Post by: Mark S on 10/14/2015 05:10 PM
@oldAtlas_Eguy you do realize that a SLS that can put 100mt in LEO is a Block 2 variant. We only have the Block-1 and maybe the Block-1B available for the foreseeable future. I am guessing the SLS can get roughly 50 or 60 mt up to LEO with a non-Block-2 variant.

No, Block-2 is 130mt. Block-1 is basically the development version. Block-1B is the future workhorse variant, and it will put more than 100mt into LEO.

Mark S.
Title: Re: SLS General Discussion Thread 2
Post by: ThereIWas3 on 10/14/2015 05:27 PM
It could be manned continuously to monitor the fuels, and make maybe have robotic arms for helping SEP tugs refuel, or various vehicles to dock and refuel for out flights.

I do not think it needs to be continuously manned to do those things.  If the USAF is talking about assmbling large structures in space using entirely remotely operated technology.   And continuous occupation at an EM Lagrange point has nasty levels to worry about.
Title: Re: SLS General Discussion Thread 2
Post by: oldAtlas_Eguy on 10/14/2015 05:48 PM
@oldAtlas_Eguy you do realize that a SLS that can put 100mt in LEO is a Block 2 variant. We only have the Block-1 and maybe the Block-1B available for the foreseeable future. I am guessing the SLS can get roughly 50 or 60 mt up to LEO with a non-Block-2 variant.

No, Block-2 is 130mt. Block-1 is basically the development version. Block-1B is the future workhorse variant, and it will put more than 100mt into LEO.

Mark S.
The basic point I was trying to make was about the validity of the economic model. To say using one LV over another would be generally less total cost cannot be made, it is a specific case by case situation.
Title: Re: SLS General Discussion Thread 2
Post by: 93143 on 10/14/2015 09:06 PM
The basic point I was trying to make was about the validity of the economic model. To say using one LV over another would be generally less total cost cannot be made, it is a specific case by case situation.

Did you read the paper or is that your opinion?  You do kinda sound like you have a source for your numbers...

I was referencing the abstract, not to prove that SLS is always better but to show that $/kg is not necessarily the more important metric as Coastal Ron suggested.
Title: Re: SLS General Discussion Thread 2
Post by: oldAtlas_Eguy on 10/14/2015 11:37 PM
The basic point I was trying to make was about the validity of the economic model. To say using one LV over another would be generally less total cost cannot be made, it is a specific case by case situation.

Did you read the paper or is that your opinion?  You do kinda sound like you have a source for your numbers...

I was referencing the abstract, not to prove that SLS is always better but to show that $/kg is not necessarily the more important metric as Coastal Ron suggested.
I just created my own simplistic eco model of the problem and relationships and checked what the results were. It showed that while the $/kg difference between the two launchers is important it is not the controlling factor but the factor of total modules to unique module designs. Its another form of economies of scale. If the quantities are high enough the high costs of design for each unique design can be overcome by the high number of identical modules reducing the total cost of the system. Launch costs are actually only a portion of the total costs at most 50% or even a lot less at almost 10%. Like I said because of the multiple variables at play singling out any one variable as the definitive decider is an error. Because launch costs are an additional cost and not the most significant cost reduction of launch costs does not have as much effect as some would believe and in some cases other cost increases are greater than the cost savings using a cheaper launcher.

The only somewhat rule of thumb is if the larger launcher is also the cheaper $/kg then it may be the best solution but watch out for volume (faring space for the payload) may be a limiting item on the larger LV making a smaller booster that also has a large volume to payload weight possibly a better value.
Title: Re: SLS General Discussion Thread 2
Post by: Coastal Ron on 10/15/2015 12:35 AM
I just created my own simplistic eco model of the problem and relationships and checked what the results were. It showed that while the $/kg difference between the two launchers is important it is not the controlling factor but the factor of total modules to unique module designs.

This assumes the construction method is based on assembling modules, and that may not be the ultimate design, or at least not a majority of the ultimate design.  For instance, with a rotating space station quite a bit of the total mass will likely be taken up by supports and floors and such, not living space, and those would likely be more mass dense than living space modules would be (with no real designs, "likely" is the operative word).

However, this discussion about rotating space stations is really premature, since based on my calculations the mass of such stations, even if they are only .5G or so, would be far, far bigger than the mass of the ISS, which is 450mT.  And I don't see any funded need for such a structure in the near future.
Title: Re: SLS General Discussion Thread 2
Post by: oldAtlas_Eguy on 10/15/2015 02:35 PM
I just created my own simplistic eco model of the problem and relationships and checked what the results were. It showed that while the $/kg difference between the two launchers is important it is not the controlling factor but the factor of total modules to unique module designs.

This assumes the construction method is based on assembling modules, and that may not be the ultimate design, or at least not a majority of the ultimate design.  For instance, with a rotating space station quite a bit of the total mass will likely be taken up by supports and floors and such, not living space, and those would likely be more mass dense than living space modules would be (with no real designs, "likely" is the operative word).

However, this discussion about rotating space stations is really premature, since based on my calculations the mass of such stations, even if they are only .5G or so, would be far, far bigger than the mass of the ISS, which is 450mT.  And I don't see any funded need for such a structure in the near future.
Actually the eco module applies to even a single large unit flown on SLS where it takes 3 unique units flown on FHR. But if it was 3 identical units flown on SLS and then 3 flights each of 3 unique units on FHR there may be a cost savings using FHR over that of SLS. Like I said it is a case by case economic analysis problem to determine which will be cheaper due to the added costs of designing multiple units vs a single larger unit. It is that last that is the economic problem. If the larger unit can be substituted by using say 3 identical smaller units then SLS losses hands down in total costs for the system (Launch + unit development+unit manufacturing+on orbit assembly(if needed)). This problem is basically due to the high cost of development vs the cost of manufacture once the design has been done. This ratio is usually somewhere around 5 (development/design to manufacturing). This means that quantity and cost of launch are related to total system costs. High quantity and smaller lower launch costs will equal lower total system costs but exactly where this crossover point is for any given unit is a function of the costs for the unit (design and manufacturing + the number of launches at a launch cost for a specific booster).

Here Unit = a unique payload of some kind
Title: Re: SLS General Discussion Thread 2
Post by: A_M_Swallow on 10/21/2015 08:17 PM
Quote
The L point station should also be modular enough to have replacements periodically for continuous operations.  It should also be able to expand into a fuel depot for Mars transits, and a warehouse type depot for Mars cargo departures.

Using Earth analogies, we don't combine hotels with gas stations, for a number of reasons, but even in space I'm not sure there would be enough synergy or need to combine them.

Since it is for short stay and for work rather than play the spacestation would be more a motel than hotel.

In Britain motels and petrol stations are combined - they are called motorway service stations. I do accept the food & bedrooms are low quality and the fuel is expensive. Different buildings but on the same campus.
Title: Re: SLS General Discussion Thread 2
Post by: rayleighscatter on 10/22/2015 10:32 PM
So since the adapter/interstage is shown as being foam covered as well as the core would the two likely be joined before foam is applied or can the foam be applied to both and then connect the two parts?
Title: Re: SLS General Discussion Thread 2
Post by: Mark S on 10/23/2015 03:49 AM
So since the adapter/interstage is shown as being foam covered as well as the core would the two likely be joined before foam is applied or can the foam be applied to both and then connect the two parts?

I don't think the adapter is foam covered. It's just painted orange to match the tanks for some reason. It has to be painted, so why not orange (other than flying carrot jokes)?

But in my opinion, it should be white. The tanks are only orange because that's the natural color of the foam insulation, and they don't want to paint it, in order to save weight. Not because orange is the cool color now. Or ever, in spite of OITNB.

Mark S.
Title: Re: SLS General Discussion Thread 2
Post by: ISP on 10/23/2015 05:39 AM
So since the adapter/interstage is shown as being foam covered as well as the core would the two likely be joined before foam is applied or can the foam be applied to both and then connect the two parts?

I don't think the adapter is foam covered. It's just painted orange to match the tanks for some reason. It has to be painted, so why not orange (other than flying carrot jokes)?

But in my opinion, it should be white. The tanks are only orange because that's the natural color of the foam insulation, and they don't want to paint it, in order to save weight. Not because orange is the cool color now. Or ever, in spite of OITNB.

Mark S.

The LVSA is covered in foam now. Not sure why, but it is, per this:

http://www.nasa.gov/press-release/nasa-completes-critical-design-review-for-space-launch-system (http://www.nasa.gov/press-release/nasa-completes-critical-design-review-for-space-launch-system)

Quote
Critical design reviews for the individual SLS elements of the core stage, boosters and engines were completed successfully as part of this milestone. Also as part of the CDR, the program concluded the core stage of the rocket and Launch Vehicle Stage Adapter will remain orange, the natural color of the insulation that will cover those elements, instead of painted white.
Title: Re: SLS General Discussion Thread 2
Post by: sdsds on 10/23/2015 05:50 AM
Given the anticipated production rate why not paint each LVSA with a unique color pattern, so in photos of the vehicles it will always be easy to identify them? Or maybe to get that retro "Jupiter" look they seem to love they could paint on the vehicle's serial number in big black letters using H-U-N-T-S-V-I-L-E-X code?
Title: Re: SLS General Discussion Thread 2
Post by: Proponent on 10/23/2015 09:11 AM
As an aside, the image above is likely reversed (http://forum.nasaspaceflight.com/index.php?topic=25741.msg766452#msg766452), the actual designation being AMXHA.

EDIT:  Corrected link.
Title: Re: SLS General Discussion Thread 2
Post by: Mark S on 10/23/2015 06:04 PM
So since the adapter/interstage is shown as being foam covered as well as the core would the two likely be joined before foam is applied or can the foam be applied to both and then connect the two parts?

I don't think the adapter is foam covered. It's just painted orange to match the tanks for some reason. It has to be painted, so why not orange (other than flying carrot jokes)?

But in my opinion, it should be white. The tanks are only orange because that's the natural color of the foam insulation, and they don't want to paint it, in order to save weight. Not because orange is the cool color now. Or ever, in spite of OITNB.

Mark S.

The LVSA is covered in foam now. Not sure why, but it is, per this:

http://www.nasa.gov/press-release/nasa-completes-critical-design-review-for-space-launch-system (http://www.nasa.gov/press-release/nasa-completes-critical-design-review-for-space-launch-system)

Quote
Critical design reviews for the individual SLS elements of the core stage, boosters and engines were completed successfully as part of this milestone. Also as part of the CDR, the program concluded the core stage of the rocket and Launch Vehicle Stage Adapter will remain orange, the natural color of the insulation that will cover those elements, instead of painted white.

Thanks for the correction! I missed that.

Like you, I have no idea why they would put foam on the LVSA. Does anyone else have any insight on that decision?

Mark S.
Title: Re: SLS General Discussion Thread 2
Post by: TomH on 10/26/2015 09:20 PM
I have no idea why they would put foam on the LVSA. Does anyone else have any insight on that decision?

The answer is in Chris' and Chris's new article.

Quote
The post-CDR design does include more foam on the top end of the rocket after an additional decision included a call for the LVSA (Launch Vehicle to Stage Adaptor) to have foam on the outside, based on the latest thermal analysis.

Given the LVSA has the core stage LOX tank below it, the ICPS LOX tank inside, and the ICPS LH2 tank above it, it is expected this area of the rocket will become cold during the final countdown and form ice on the outside.
Title: Re: SLS General Discussion Thread 2
Post by: TomH on 10/26/2015 09:23 PM
And from today's new article:

Quote
Presently, SLS Near-Term Look-Ahead schedules show that the VAC will be turned over from the construction contractor ESAB to Boeing at the end of this week on 31 October.

Delivery on Halloween Day, hope this doesn't turn out to be a Trick or Treat? delivery.
Title: Re: SLS General Discussion Thread 2
Post by: dror on 10/27/2015 05:38 PM
Quote
... because for every pound of paint applied, a pound of payload delivery ability would have been removed from SLS’s capability.

Is that correct ?
Title: Re: SLS General Discussion Thread 2
Post by: notsorandom on 10/27/2015 06:12 PM
Quote
... because for every pound of paint applied, a pound of payload delivery ability would have been removed from SLS’s capability.

Is that correct ?
It is close to correct. Mass saved from the last rocket stage of any rocket will be close to the amount of extra payload mass. In the case where it has no upper stage the core is the last stage so not painting will add payload mass roughly equal to the mass of the unused paint. However SLS will also fly with the ICPS and EUS upper stages. So when flying in those configurations the mass savings in paint will increase payload but not at a near 1:1 ratio. It will still add a bit of payload mass though since the core is jettisoned late in flight. That paint needs to be hauled through a good amount of the imparted delta V.
Title: Re: SLS General Discussion Thread 2
Post by: BrightLight on 10/28/2015 05:27 PM
With the CDR for the SLS core passed as well as the Orion EM-2 in process - I'm getting to the point I believe SLS will actually fly!

Title: Re: SLS General Discussion Thread 2
Post by: rayleighscatter on 11/10/2015 01:49 AM


Like you, I have no idea why they would put foam on the LVSA. Does anyone else have any insight on that decision?

Mark S.
From a NASA blog post today, for what it's worth:
Quote
Also insulated with the orange foam is the Launch Vehicle Stage Adapter, the conical section that connects the core stage with the upper stage. Because this section widens so much from top to bottom, it will experience extreme aerodynamic heating during launch, and the foam will protect the metal underneath from the high temperatures.
Title: Re: SLS General Discussion Thread 2
Post by: llanitedave on 11/10/2015 03:51 PM
That's interesting.  I wonder what makes launch heating on the SLS adapter more problematic than it would have been on the Saturn V second-third stage adapter.
Title: Re: SLS General Discussion Thread 2
Post by: Proponent on 11/10/2015 03:59 PM
Maybe the use of SRBs increases aero heating?
Title: Re: SLS General Discussion Thread 2
Post by: Starlab90 on 11/11/2015 12:08 AM
That's interesting.  I wonder what makes launch heating on the SLS adapter more problematic than it would have been on the Saturn V second-third stage adapter.

I'm pretty sure it's because SLS will have a higher max Q than the Saturn V did, but I need to double-check the numbers.
Title: Re: SLS General Discussion Thread 2
Post by: Mark S on 11/11/2015 08:40 PM
Dedicated EM-1 section coming soon, but here's another cool overview of the flow to EM-1 via Chris Gebhardt:
http://www.nasaspaceflight.com/2015/11/road-em-1-nasa-hardware-milestones-sls-debut-flight/

Another great story, Chris and Chris!

I was wondering about the booster segment arrival schedule, as described here:

Quote
Under the current Integrated Mission Milestone Summary, the Forward and Center SRB segments will arrive at the Kennedy Space Center in September and October 2017.

This will be followed by the delivery of the Aft Skirts in November/December 2017 and then the Aft segments of the SRBs in late-January/early-February 2018.

Finally, the Forward segments are currently slated to arrive at the Kennedy Space Center in early March 2018.

You describe the Forward segments arriving in both Sep/Oct 2017 and Mar 2018. And I don't see mention of the Forward-Center or Aft-Center segments anywhere in there. (or is it Center-Forward and Center-Aft?). Do you have schedule info for those segments also?

Thanks.
Title: Re: SLS General Discussion Thread 2
Post by: Johnnyhinbos on 12/09/2015 11:09 PM
I'd be curious to know how long it would take to build the SECOND SLS system. Meaning, there is so much time spent developing the tooling and doing the certification for this first SLS that I'm curious to see how long it would take just to build the second SLS once all this tooling and certification process has been completed.

Title: Re: SLS General Discussion Thread 2
Post by: Coastal Ron on 12/10/2015 02:21 AM
I'd be curious to know how long it would take to build the SECOND SLS system. Meaning, there is so much time spent developing the tooling and doing the certification for this first SLS that I'm curious to see how long it would take just to build the second SLS once all this tooling and certification process has been completed.

Just to establish a best case for what Boeing can do, the outgoing SLS Program Manager at Boeing was quoted as saying (http://spacenews.com/an-interview-with-boeings-outgoing-sls-program-manager/):

"Boeing has Michoud set up to stamp out enough stages for one SLS a year — two at most with the factory’s current manufacturing capabilities, and then only if NASA pours more money and personnel into the facility."

My background is in manufacturing operations, and quite often I've overseen the scheduling of new products (and sometimes factories).  Even with incremental upgrades of products there are usually processes that take time to dial in, and with the SLS the production rate is so low that they can't get enough experience to dial in their processes until many years from now.  Of course lots of time between builds means that the staff has a lot of time to do dry-runs in between production runs, so that could help them optimize their processes without having to actually build completed parts.

But still, you need to build the actual parts in order to validate that you know how to build the product within the planned/allocated amount of time.

My guess would be about a year for SLS-2, which is probably about 120-140% above the eventual production time.
Title: Re: SLS General Discussion Thread 2
Post by: bob the martian on 12/10/2015 02:51 PM
I'd be curious to know how long it would take to build the SECOND SLS system. Meaning, there is so much time spent developing the tooling and doing the certification for this first SLS that I'm curious to see how long it would take just to build the second SLS once all this tooling and certification process has been completed.

Just to establish a best case for what Boeing can do, the outgoing SLS Program Manager at Boeing was quoted as saying (http://spacenews.com/an-interview-with-boeings-outgoing-sls-program-manager/):

"Boeing has Michoud set up to stamp out enough stages for one SLS a year — two at most with the factory’s current manufacturing capabilities, and then only if NASA pours more money and personnel into the facility."

My background is in manufacturing operations, and quite often I've overseen the scheduling of new products (and sometimes factories).  Even with incremental upgrades of products there are usually processes that take time to dial in, and with the SLS the production rate is so low that they can't get enough experience to dial in their processes until many years from now.  Of course lots of time between builds means that the staff has a lot of time to do dry-runs in between production runs, so that could help them optimize their processes without having to actually build completed parts.

But still, you need to build the actual parts in order to validate that you know how to build the product within the planned/allocated amount of time.

My guess would be about a year for SLS-2, which is probably about 120-140% above the eventual production time.

So, question - how are the staff at Michoud allocated for this?  Is it a small workforce that's working full-time on SLS, or a larger workforce that's part-time on SLS, part time on other projects?  IOW, is one, maybe two rockets a year enough to keep a full-time staff employed, much less keep their skills sharp?
Title: Re: SLS General Discussion Thread 2
Post by: Coastal Ron on 12/10/2015 04:28 PM
So, question - how are the staff at Michoud allocated for this?  Is it a small workforce that's working full-time on SLS, or a larger workforce that's part-time on SLS, part time on other projects?  IOW, is one, maybe two rockets a year enough to keep a full-time staff employed, much less keep their skills sharp?

I don't know, but my guess is that the factory is staffed with full-time workers, and that they don't work on any other contracts.  However they may not have hired all of the eventually positions they would need for full-rate production (which for now would be assumed to be 1/year).

And by virtue of how the SLS is assembled, I'm assuming people will move with the parts as they go through the different work stations, so they would need people with good general skills that can do many tasks.
Title: Re: SLS General Discussion Thread 2
Post by: TomH on 12/10/2015 09:10 PM
So, question - how are the staff at Michoud allocated for this?  Is it a small workforce that's working full-time on SLS, or a larger workforce that's part-time on SLS, part time on other projects?  IOW, is one, maybe two rockets a year enough to keep a full-time staff employed, much less keep their skills sharp?

I don't know, but my guess is that the factory is staffed with full-time workers, and that they don't work on any other contracts.  However they may not have hired all of the eventually positions they would need for full-rate production (which for now would be assumed to be 1/year).

And by virtue of how the SLS is assembled, I'm assuming people will move with the parts as they go through the different work stations, so they would need people with good general skills that can do many tasks.

Back in the days of Saturn, I would have seen the validity in that. Nowadays, however, I would think that most work on machines of this complexity is CAM-robotic and that many of the technicians monitor the computer driven robotic tools. Human machinists lose skills over time if not practiced enough, and institutional memory is lost over time via attrition. In this day and age, however, a CAM program can be kept in storage devices and employed at any time. You have stated that you were involved in manufacturing, but were you involved in manufacturing sophisticated modern rockets? What did you manufacture and to what degree was the product dependent on a human machinist's skills versus modern integrated computer controlled robots? You have never mentioned the product field as being ultra-sophisticated, so I am not convinced that the manufacturing model you describe remains valid.
Title: Re: SLS General Discussion Thread 2
Post by: Coastal Ron on 12/11/2015 12:16 AM
Back in the days of Saturn, I would have seen the validity in that. Nowadays, however, I would think that most work on machines of this complexity is CAM-robotic and that many of the technicians monitor the computer driven robotic tools.

No doubt we're more automated these days, but not everything is 100% automated.  And you have to remember that you can only successfully automate something that you completely understand.  So if you haven't built something yet, you can't completely understand if your solutions will work the first time, every time.  The experience with the SLS Vertical Assembly Center, which is a product, is an indication of that.

Quote
Human machinists lose skills over time if not practiced enough, and institutional memory is lost over time via attrition. In this day and age, however, a CAM program can be kept in storage devices and employed at any time.

I was around to see the changeover from cam actuated tools to CAM (Computer-aided manufacturing).  It's been interesting to see how the labor content, and type of labor changed.  Labor is still required though.

Quote
You have stated that you were involved in manufacturing, but were you involved in manufacturing sophisticated modern rockets? What did you manufacture and to what degree was the product dependent on a human machinist's skills versus modern integrated computer controlled robots?

To a certain extent, making components is pretty much the same regardless what the end product is.  Stamped, injection molded, milled, turned, drilled, welded - the processes haven't changed much, just the machinery that we use to control the processes.  And assembly, to a certain extent, for rockets is not much different from other similar sized products.  It's just the certification and inspection processes that are different.

Quote
You have never mentioned the product field as being ultra-sophisticated, so I am not convinced that the manufacturing model you describe remains valid.

What makes you think rockets are "ultra-sophisticated"?  They are pretty much just up-sized aluminum cans.

As for me, early on I started out in a machine-heavy environment making component parts and small assemblies (as well as tooling too).  Then I moved on to military electronic systems, and later high-volume consumer electronic products.

All of the products I've worked on had high tolerances, either from a fit standpoint or a electronic functionality standpoint.  And especially when you're building high-volume consumer products, everything has to be dialed in and perfect - that takes time and experience with your product.

Boeing has experience in building large assemblies, and building rockets is not a new endeavor.  But dialing in your manufacturing processes takes more than one unit, and anyone in manufacturing engineering would be able to verify that.

My $0.02
Title: Re: SLS General Discussion Thread 2
Post by: NovaSilisko on 12/16/2015 07:18 AM
SLS funded beyond request again?

Quote
Jeff Foust @jeff_foust
Exploration gets $4.03B, including $1.27B for Orion and $2B for SLS, the latter far above the administration’s request.
Title: Re: SLS General Discussion Thread 2
Post by: llanitedave on 12/16/2015 04:42 PM
If it's going to be used to launch a Europa probe in 2022, they need to advance the schedule a bit.  That might explain the extra funding.
Title: Re: SLS General Discussion Thread 2
Post by: rcoppola on 12/16/2015 04:47 PM
If it's going to be used to launch a Europa probe in 2022, they need to advance the schedule a bit.  That might explain the extra funding.
The fact they specifically included a "lander" in the language of a Europa mission, they may need a bit more time anyways. Maybe not. But they also explicitly put in language to fund the EUS and essentially replace ICPS for EM-2.
Title: Re: SLS General Discussion Thread 2
Post by: Endeavour_01 on 12/17/2015 10:10 PM
If it's going to be used to launch a Europa probe in 2022, they need to advance the schedule a bit.  That might explain the extra funding.
The fact they specifically included a "lander" in the language of a Europa mission, they may need a bit more time anyways. Maybe not. But they also explicitly put in language to fund the EUS and essentially replace ICPS for EM-2.

What we could see is the second ICPS being used for the Europa mission in 2022-23 since it will not be flying on EM-2. At that point it would be a flight proven stage and I remember reading somewhere that it does slightly better than the EUS for EC (don't know what happens when you add the lander though).


Edit: I just remembered that they couldn't use ICPS after EUS is online because of the changes to the umbilicals on the ML.

P.S. For my friend Coastal Ron who is always worried about Congress paying for payloads for SLS, here is another one. :)
Title: Re: SLS General Discussion Thread 2
Post by: Ben the Space Brit on 12/21/2015 02:47 PM
Okay, I'm hoping that I can get some solid information here. As far as I know, so far, the SLS missions are:

EM-1 - Uncrewed trans-Lunar flyby with iCPS - 2018;
SLS-02 - Europa probe launch with EUS or iCPS, depending on the exact schedule of EM-2 - 2022-ish;
EM-2 - ? (AFAIK, the ARM is still baseline although there does seem to be something of a retreat underway) - 2022/23;
SLS-04 (?) - ? (Possible cargo precursor for EM-3) - Undefined;
EM-3 - ? (No mission defined as yet) - Undefined.

IIRC, EM-3's launch vehicle, SLS-05, represents the point where the RS-25D stockpile run out and SLS needs to switch to RS-25E if there are to be further missions in the program. What is the latest time, realistically speaking, when Aeroject/PWR need to start building the tooling for RS-25E in order to avoid serious delays?
Title: Re: SLS General Discussion Thread 2
Post by: notsorandom on 12/21/2015 03:04 PM
EM-1 will be proving many things from the rocket to the spacecraft. That make sense. However at this point we can't be too sure that there will be a payload needing a ride for the EUS test flight and repeating EM-1 with the EUS seems wasteful. I wonder if it would be possible to do enough testing an analysis to skip the uncrewed test flight. The EUS uses a fair amount of heritage components and the RL-10 is a well characterized and reliable engine.
Title: Re: SLS General Discussion Thread 2
Post by: Hog on 12/21/2015 09:50 PM
Okay, I'm hoping that I can get some solid information here. As far as I know, so far, the SLS missions are:

EM-1 - Uncrewed trans-Lunar flyby with iCPS - 2018;
SLS-02 - Europa probe launch with EUS or iCPS, depending on the exact schedule of EM-2 - 2022-ish;
EM-2 - ? (AFAIK, the ARM is still baseline although there does seem to be something of a retreat underway) - 2022/23;
SLS-04 (?) - ? (Possible cargo precursor for EM-3) - Undefined;
EM-3 - ? (No mission defined as yet) - Undefined.

IIRC, EM-3's launch vehicle, SLS-05, represents the point where the RS-25D stockpile run out and SLS needs to switch to RS-25E if there are to be further missions in the program. What is the latest time, realistically speaking, when Aeroject/PWR need to start building the tooling for RS-25E in order to avoid serious delays?
EM-1 2018 Will fly main engines(ME) ME2045, ME2056, ME2058 and ME2060
SLS-02 2021 Will fly engines ME2047, ME2059 and new unflown engines ME2062(built Sept. 2010) and ME2063(built in early 2015)
EM-2 2023 Will fly engines ME2048, ME2054, ME2057 and ME2061
SLS-04 (?) 2025 Will fly engines ME2044, ME2050, ME2051 and ME2052

 The backup engines for EM-1 are the scheduled primary flight engines for SLS-02, scheduled primary flight engines for a mission, are the previous missions backup engines.  When it comes time to fly SLS-04, as it stands now, there is no backup engines in existence.  Perhaps this should give us a clue as to when these 6 new "legacy" build RS-25 engines that NASA has ordered, will need to be ready to run?  Not only to actually fly SLS's 5th mission, but to support SLS's 4th mission (SLS-04) as standby engines.
Title: Re: SLS General Discussion Thread 2
Post by: TrevorMonty on 12/21/2015 10:50 PM
Okay, I'm hoping that I can get some solid information here. As far as I know, so far, the SLS missions are:

EM-1 - Uncrewed trans-Lunar flyby with iCPS - 2018;
SLS-02 - Europa probe launch with EUS or iCPS, depending on the exact schedule of EM-2 - 2022-ish;
EM-2 - ? (AFAIK, the ARM is still baseline although there does seem to be something of a retreat underway) - 2022/23;
SLS-04 (?) - ? (Possible cargo precursor for EM-3) - Undefined;
EM-3 - ? (No mission defined as yet) - Undefined.

IIRC, EM-3's launch vehicle, SLS-05, represents the point where the RS-25D stockpile run out and SLS needs to switch to RS-25E if there are to be further missions in the program. What is the latest time, realistically speaking, when Aeroject/PWR need to start building the tooling for RS-25E in order to avoid serious delays?

EM-1 mission is planned to enter Lunar DRO via a lunar flyby. This makes a lot of sense as at this stage it looks like most Orion flights will be going to Lunar DRO. The Asteriod will be stationed there a long with DSH.

http://www.nasaspaceflight.com/2013/07/em-1-nasa-request-changes-debut-slsorion-mission/
Title: Re: SLS General Discussion Thread 2
Post by: Steven Pietrobon on 12/21/2015 11:09 PM
What is the latest time, realistically speaking, when Aeroject/PWR need to start building the tooling for RS-25E in order to avoid serious delays?

That process has already started.

"The lead time is approximately 5 or 6 years to build and certify the first new RS-25 engine, Van Kleek told Universe Today in an interview. Therefore NASA needed to award the contract to Aerojet Rocketdyne now so that its ready when needed."

http://www.universetoday.com/123580/nasa-awards-contract-to-aerojet-rocketdyne-to-restart-rs-25-engine-production-for-sls-mars-rocket/
Title: Re: SLS General Discussion Thread 2
Post by: Kansan52 on 12/21/2015 11:24 PM
Coastal Ron, sorrey to ask this so late. In you comment "All of the products I've worked on had high tolerances..." do you mean items with really close tolerances, says much less than 1% tolerances? What I have heard and called 'tight' tolerances. Repairing consumer electronics, some thing have as much as 20% tolerances and other have such tight tolerances that the OEM piece is the only thing that works.
Title: Re: SLS General Discussion Thread 2
Post by: clongton on 01/14/2016 04:14 PM
Some disturbing conclusions.
Discuss

http://spacenews.com/nasa-safety-panel-worries-about-schedule-pressure-on-exploration-programs/ (http://spacenews.com/nasa-safety-panel-worries-about-schedule-pressure-on-exploration-programs/)
Title: Re: SLS General Discussion Thread 2
Post by: oldAtlas_Eguy on 01/14/2016 06:35 PM
This on a follow-on to the KSC info is not good for SLS's schedule. EM-2 could end up out in 2025. After a EUS test flight with another unmanned test of Orion in 2023 to test the ECLSS and other things like the new heat shield.
Title: Re: SLS General Discussion Thread 2
Post by: psloss on 01/14/2016 07:00 PM
The full report is available here:
http://oiir.hq.nasa.gov/asap/documents/2015_ASAP_Annual_Report.pdf

(Also attached.)
Title: Re: SLS General Discussion Thread 2
Post by: Mark S on 01/14/2016 08:59 PM
Some disturbing conclusions.
Discuss

http://spacenews.com/nasa-safety-panel-worries-about-schedule-pressure-on-exploration-programs/ (http://spacenews.com/nasa-safety-panel-worries-about-schedule-pressure-on-exploration-programs/)


Schedule pressure? What schedule pressure?!  I haven't seen NASA in a hurry to do anything SLS-related since the NASA Authorization Act of 2010 was signed into law. They have taken their sweet time every step of the way, to the extent of being threatened with a Congressional subpoena over all the delays in starting the program.

All while swearing up and down every single year that they didn't need any additional funding for SLS to meet the legal requirements of the act (IOC, reports, etc).

Mark S.

Edit: And by NASA, I mean the Administration and NASA executive level. Not the guys in the trenches!
Title: Re: SLS General Discussion Thread 2
Post by: rayleighscatter on 01/23/2016 12:57 AM
Quote
An aft skirt similar to one that will be used on a solid rocket booster (SRB) that will help launch NASA’s Space Launch System (SLS) rocket into space was transported from the Booster Fabrication Facility to the Rotation, Processing and Surge Facility (RPSF) at the agency’s Kennedy Space Center in Florida.

The aft skirt will remain in the RPSF and be readied for simulated stacking operations with a pathfinder, or test version, of a solid rocket booster. February 1 will mark the official start date for booster pathfinder operations after the aft skirt is inspected and undergoes limited processing.

Segments of the pathfinder SRB will arrive from Promontory, Utah, to Kennedy in mid-February and will be transported to the RPSF.

Engineers and technicians with NASA and industry partners will conduct a series of lifts, moves and stacking operations using the aft skirt and pathfinder SRB to simulate how SRB will be processed in the RPSF to prepare for an SLS/Orion mission.

The pathfinder operations will help to test recent upgrades to the RPSF facility as the center prepares for NASA’s Exploration Mission-1, deep-space missions, and the journey to Mars.
Title: Re: SLS General Discussion Thread 2
Post by: Hotblack Desiato on 01/28/2016 09:17 AM
Regarding the production and flight rate of SLS, which really looks quite low. I tried to figure out why they did this approach.

My only guess so far: They've set up a production line for 1-2 SLS per year to learn how to operate SLS and its production line. After a few flights, they should know about the difficulties of SLS during production, and what might be needed to solve them. At the flight itself, I expect SLS to be pretty much flawless (unless something happens that they did not anticipate). To stress a metaphor that was used a few pages back: learn to bake such a cake before going into bakery scale production.

With the EUS (I think, that will be the only US, that they will use) and a RS-25F (the one after E, where AJ expects it to be much cheaper, since they'd have learned from their production aswell), they could ramp up the production to several unity per year (they might even go up to 10-12, but that would be very high. 5 additional SLS should be doable).

That will still leave the problem where to launch such an amount of rockets from. 39B won't be sufficient. It should be possible to convert one or two of the older launch pads to a SLS-pad, or set up entirely new pads off shore (the art of making islands with lots of concrete), connected with the crawler-ways, or even become a tenant in boca chica.
Title: Re: SLS General Discussion Thread 2
Post by: AncientU on 01/28/2016 12:24 PM
Regarding the production and flight rate of SLS, which really looks quite low. I tried to figure out why they did this approach.

My only guess so far: They've set up a production line for 1-2 SLS per year to learn how to operate SLS and its production line. After a few flights, they should know about the difficulties of SLS during production, and what might be needed to solve them. At the flight itself, I expect SLS to be pretty much flawless (unless something happens that they did not anticipate). To stress a metaphor that was used a few pages back: learn to bake such a cake before going into bakery scale production.

With the EUS (I think, that will be the only US, that they will use) and a RS-25F (the one after E, where AJ expects it to be much cheaper, since they'd have learned from their production aswell), they could ramp up the production to several unity per year (they might even go up to 10-12, but that would be very high. 5 additional SLS should be doable).

That will still leave the problem where to launch such an amount of rockets from. 39B won't be sufficient. It should be possible to convert one or two of the older launch pads to a SLS-pad, or set up entirely new pads off shore (the art of making islands with lots of concrete), connected with the crawler-ways, or even become a tenant in boca chica.

So you're saying that visionary strategic thinking has established this pace...
One day, we'll see SLS launch every month or two.

Novel.
Title: Re: SLS General Discussion Thread 2
Post by: Hotblack Desiato on 01/28/2016 01:17 PM
So you're saying that visionary strategic thinking has established this pace...
One day, we'll see SLS launch every month or two.

Novel.

At least it is better than thinking that they are a bunch of funny guys who really expect, that it is economically feasable to launch one rocket for 1.5 billion US$ (before adding any payload).

I just provided a possible alternative explanation, which would look a bit better.
Title: Re: SLS General Discussion Thread 2
Post by: rayleighscatter on 01/28/2016 09:20 PM
That will still leave the problem where to launch such an amount of rockets from. 39B won't be sufficient. It should be possible to convert one or two of the older launch pads to a SLS-pad, or set up entirely new pads off shore (the art of making islands with lots of concrete), connected with the crawler-ways, or even become a tenant in boca chica.
If the cadence starts to pick up NASA would likely just retake possession of 39A once the lease expires.
Title: Re: SLS General Discussion Thread 2
Post by: Kansan52 on 01/28/2016 09:44 PM
First problem, they cannot produce more that 1 a year as set-up. Maybe 2 a year if you increase the workforce. More than 2 a year means more equipment to build more plus more work force. And that is simply building the core. SRBs and engines also cannot support more than maybe 2 a year without greater infrastructure and workforce.

Flip a coin and say the billions to do that happens. If memory serves, they have two mobile transporters. So 39-b should be able to handle 1 flight per month. Probably requires increase workforce for stacking and pad repairs.

So the reason production is set to one a year is money. Some estimates say to produce and launch one SLS is $1.5 billion. So to launch 11 more a year would require another $16.5 billion. I do not see Congress doing that.
Title: Re: SLS General Discussion Thread 2
Post by: mike robel on 01/28/2016 09:46 PM
Nope.  Only one mobile launch tower, so you can't begin to assemble the next one, till the one on the pad is gone.  Saturn V's could go at about 3 month intervals (3 mobile towers).  Don't know how long these would take to assemble and check out.
Title: Re: SLS General Discussion Thread 2
Post by: Kansan52 on 01/28/2016 10:41 PM
Well, we probably are arguing over nothing but there were and are two crawler transporters, CT-1 and CT-2. I concede only CT-1 is being modified for SLS operations. CT-2 is being upgraded (or finished upgrading) so it could be used in the future but not ready to use now. So you are correct on that as a bottleneck.

The time for preparing the flight could mean one transporter could be used for a once a month cycle. A day to the pad. 2 days for launch. A day back. So three weeks to stack before the next launch. Weather and equipment days would also stress such a wild ass guess of operations tempo.

Now something else that could be a bottleneck, I can't remember had many bays are available in the VAB. They were trying to lease those out as well. But if they are down to one CT, then they only need one bay.

If memory serves, it was also budget that held Saturn V launches to their launch tempo.

So I would still say budget (money) is the constraining factor.
Title: Re: SLS General Discussion Thread 2
Post by: Hotblack Desiato on 01/28/2016 10:43 PM
First problem, they cannot produce more that 1 a year as set-up. Maybe 2 a year if you increase the workforce. More than 2 a year means more equipment to build more plus more work force. And that is simply building the core. SRBs and engines also cannot support more than maybe 2 a year without greater infrastructure and workforce.

Flip a coin and say the billions to do that happens. If memory serves, they have two mobile transporters. So 39-b should be able to handle 1 flight per month. Probably requires increase workforce for stacking and pad repairs.

So the reason production is set to one a year is money. Some estimates say to produce and launch one SLS is $1.5 billion. So to launch 11 more a year would require another $16.5 billion. I do not see Congress doing that.

Okay, interesting.

So it is just not possible to set up a second production line, designed for a higher production rate? Who would have known that this is michouds capacity limit.

Nope.  Only one mobile launch tower, so you can't begin to assemble the next one, till the one on the pad is gone.  Saturn V's could go at about 3 month intervals (3 mobile towers).  Don't know how long these would take to assemble and check out.

What would be required to speed things up? Having more mobile launch towers? Even 6 SLS-launches per year could be quite interesting.
Title: Re: SLS General Discussion Thread 2
Post by: Coastal Ron on 01/28/2016 10:54 PM
Regarding the production and flight rate of SLS, which really looks quite low. I tried to figure out why they did this approach.

My only guess so far: They've set up a production line for 1-2 SLS per year to learn how to operate SLS and its production line.

No, it's more simple than that.  There is no defined need yet for the SLS, so no known flight cadence that they have to support.  So they built the SLS factory to something reasonable, which is to support the No-Less-Than once every 12 month safe flight rate cadence.

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After a few flights, they should know about the difficulties of SLS during production, and what might be needed to solve them.

To a degree that's true, in that every production line has to be "dialed in".  But Boeing has a lot of experience in building large flying structures, so the factory is unlikely to change much after they have validated their production processes.  And if it did change, that would be money out of NASA's pocket, which means they would have to find room in their budget for it - meaning production improvements would compete with SLS mission hardware development.

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At the flight itself, I expect SLS to be pretty much flawless (unless something happens that they did not anticipate).

While there is always the chance of something unexpected happening, we as a nation are pretty good at rocket building.

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That will still leave the problem where to launch such an amount of rockets from. 39B won't be sufficient.

As I recall 39B was not going to be a bottleneck until the SLS flight rate gets pretty high (more than one a month?), which if it was needed to be that high then a new launch pad would be the least costly item for NASA to be worried about...
Title: Re: SLS General Discussion Thread 2
Post by: Kansan52 on 01/28/2016 11:19 PM

So it is just not possible to set up a second production line, designed for a higher production rate? Who would have known that this is michouds capacity limit.


I am not sure about Michouds capacity. They do have more than one project there at a time. But there may be empty space for more production equipment.

I'm not trying to say it is not possible to physically expand production facilities. The barrier would be funding. You know, 'No Bucks, No Buck Rogers'. The heady days of Mercury, Gemini, and Apollo saw the VAB, the crawler transporters, the launch pads and on and on because there was the political will to spend it on those projects. NASA's budget is approximately 1/3 from the peak of those days (again, if memory serves).

So, I'm not saying 'impossible'. But, to grow NASA's budget large enough to fund producing 12 SLS stacks a year, fund payloads for those stacks, and funding the launches would be more money that NASA has ever been allocated even in the peak years of Apollo.
Title: Re: SLS General Discussion Thread 2
Post by: mike robel on 01/28/2016 11:26 PM
Well, we probably are arguing over nothing but there were and are two crawler transporters, CT-1 and CT-2. I concede only CT-1 is being modified for SLS operations. CT-2 is being upgraded (or finished upgrading) so it could be used in the future but not ready to use now. So you are correct on that as a bottleneck.

The time for preparing the flight could mean one transporter could be used for a once a month cycle. A day to the pad. 2 days for launch. A day back. So three weeks to stack before the next launch. Weather and equipment days would also stress such a wild ass guess of operations tempo.

Now something else that could be a bottleneck, I can't remember had many bays are available in the VAB. They were trying to lease those out as well. But if they are down to one CT, then they only need one bay.

If memory serves, it was also budget that held Saturn V launches to their launch tempo.

So I would still say budget (money) is the constraining factor.

Nearly Nothing.  :)

There are two mobile crawlers, but only 1 mobile launch platform with tower, so as soon as you start to stack one vehicle, you have to launch it to clear the platform for the next launch vehicle.

I think, but am not sure, only 1 bay is going to be used for SLS.  That is not to say that they can't get another one ready.  One bay I think is used to store SRB segments, and the 4th was never finished, if I recall.  Of course, I am probably mistaken.  :)
Title: Re: SLS General Discussion Thread 2
Post by: Coastal Ron on 01/29/2016 12:13 AM

So it is just not possible to set up a second production line, designed for a higher production rate? Who would have known that this is michouds capacity limit.


I am not sure about Michouds capacity. They do have more than one project there at a time. But there may be empty space for more production equipment.

I'm not trying to say it is not possible to physically expand production facilities.

I don't know the potential capacity of Michoud, but capacity for building as many SLS as anyone could possibly want is not the real constraint...

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The barrier would be funding.

Yep.

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So, I'm not saying 'impossible'. But, to grow NASA's budget large enough to fund producing 12 SLS stacks a year, fund payloads for those stacks, and funding the launches would be more money that NASA has ever been allocated even in the peak years of Apollo.

If we ever get to the point where estimates are made public for SLS-sized payloads and missions, I would think we would find that SLS launch costs will not be the most significant missions costs - developing and operating the SLS-sized payloads and missions will far exceed the cost of the SLS launches themselves.  And as of today NASA has yet to fit even one SLS-sized payload or mission into it's current budget profile, so a dozen per year is just fantasy.
Title: Re: SLS General Discussion Thread 2
Post by: The Amazing Catstronaut on 01/29/2016 02:10 AM


So, I'm not saying 'impossible'. But, to grow NASA's budget large enough to fund producing 12 SLS stacks a year, fund payloads for those stacks, and funding the launches would be more money that NASA has ever been allocated even in the peak years of Apollo.

Admittedly unlikely - however, we may see incremental budget allocation rises with the nature of the times. Space is interesting to the electorate again.
Title: Re: SLS General Discussion Thread 2
Post by: AncientU on 01/29/2016 11:46 AM


So, I'm not saying 'impossible'. But, to grow NASA's budget large enough to fund producing 12 SLS stacks a year, fund payloads for those stacks, and funding the launches would be more money that NASA has ever been allocated even in the peak years of Apollo.

Admittedly unlikely - however, we may see incremental budget allocation rises with the nature of the times. Space is interesting to the electorate again.

48 RS-25Es per year...
(Double the amount produced over last couple decades, per year)
64x the planned production rate
Title: Re: SLS General Discussion Thread 2
Post by: AncientU on 01/29/2016 12:41 PM
So you're saying that visionary strategic thinking has established this pace...
One day, we'll see SLS launch every month or two.

Novel.

At least it is better than thinking that they are a bunch of funny guys who really expect, that it is economically feasable to launch one rocket for 1.5 billion US$ (before adding any payload).

I just provided a possible alternative explanation, which would look a bit better.

I suspect both ends of that duality are equally false.
The situation is much more banal, involving political influence, greed, and bureaucracy.

On the other hand, flight rate is exactly the latter -- one per year, optimistically.
Title: Re: SLS General Discussion Thread 2
Post by: sdsds on 01/29/2016 01:24 PM
I suspect both ends of that dichotomy are equally false.
The situation is much more banal, involving political influence, greed, and bureaucracy.

Yes. You know, it's that "human nature" thing.

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On the other hand, flight rate is exactly the latter -- one per year, optimistically.

I'm more optimistic than that. I think once past its teething pains SLS could be expected to fly once every 18 months with Orion, and once every 24 months without Orion. If I'm summing correctly, that adds up to an overall flight rate of once every 10.3 months. I would be mildly astonished if with all said and done Boeing and AJR couldn't produce the requisite hardware at that pace.
Title: Re: SLS General Discussion Thread 2
Post by: Scotty on 01/29/2016 08:58 PM
As far as KSC goes; we could fly an SLS every 6 months (our requirement) with what assets we now have in work:
1 VAB High Bay
The VAB Transfer Isle for SLS core preps
1 VAB Low Bay Cell for EUS preps
1 ML
1 Crawler
1 Launch Pad
1 SRB aft skirt processing facility
1 SRB segment processing facility
1 Orion assembly and check out facility
1 Orion fueling and processing facility
1 Firing Room
1 SSPF for cargo processing and preps
Title: Re: SLS General Discussion Thread 2
Post by: Jim on 01/29/2016 09:15 PM

1 SSPF for cargo processing and preps


It can't  handle encapsulated or hazardous payloads.  Without hazardous processing facility, SLS is limited to Orion.
Title: Re: SLS General Discussion Thread 2
Post by: muomega0 on 01/29/2016 09:34 PM
1 SSPF for cargo processing and preps
It can't  handle encapsulated or hazardous payloads.  Without hazardous processing facility, SLS is limited to Orion.
Wasn't SSPF in the 2016 plus up?
Title: Re: SLS General Discussion Thread 2
Post by: Coastal Ron on 01/29/2016 09:38 PM
I'm more optimistic than that. I think once past its teething pains SLS could be expected to fly once every 18 months with Orion, and once every 24 months without Orion. If I'm summing correctly, that adds up to an overall flight rate of once every 10.3 months. I would be mildly astonished if with all said and done Boeing and AJR couldn't produce the requisite hardware at that pace.

My background is in manufacturing operations, and I have no doubt that all suppliers in the SLS food chain would be able to meet whatever rate is needed.

So don't worry about how many SLS can be produced, instead focus on how many SLS need to be produced - focus on the payloads and missions that can only be lifted by the SLS.  Because it's never been about whether NASA can build an HLV, but whether NASA needs an HLV.
Title: Re: SLS General Discussion Thread 2
Post by: Robotbeat on 01/30/2016 12:18 AM
There's enough money in the world to fly SLS at a much higher flight rate than it is designed for right now (0.5 to 2 per year). And I'm sure the people pushing hard for SLS are hoping on hope that they will get China to go to Mars or something and get that money (from the US Congress, not China... not directly, at least). Which isn't going to happen any time soon.

Title: Re: SLS General Discussion Thread 2
Post by: Hotblack Desiato on 01/30/2016 12:30 AM
Yes, nobody knows if the next or next but one president suddenly has an inspiration of putting a man onto mars before the end of the decade (whichever that is). And then it could be quite handy to have a HLV available. Because we currently see how long it takes NASA to develop one.
Title: Re: SLS General Discussion Thread 2
Post by: Robotbeat on 01/30/2016 12:33 AM
Yes, nobody knows if the next or next but one president suddenly has an inspiration of putting a man onto mars before the end of the decade (whichever that is). And then it could be quite handy to have a HLV available. Because we currently see how long it takes NASA to develop one.
Right. They essentially are building SLS on the slim hope of a new space race, which I think they'd even acknowledge is a fairly slim possibility.
Title: Re: SLS General Discussion Thread 2
Post by: mike robel on 01/30/2016 01:32 AM
As far as KSC goes; we could fly an SLS every 6 months (our requirement) with what assets we now have in work:
1 VAB High Bay
The VAB Transfer Isle for SLS core preps
1 VAB Low Bay Cell for EUS preps
1 ML
1 Crawler
1 Launch Pad
1 SRB aft skirt processing facility
1 SRB segment processing facility
1 Orion assembly and check out facility
1 Orion fueling and processing facility
1 Firing Room
1 SSPF for cargo processing and preps


Thanks for this Scotty.  I appreciate the correction to my thinking.

Title: Re: SLS General Discussion Thread 2
Post by: Scotty on 01/30/2016 03:31 PM

1 SSPF for cargo processing and preps


It can't  handle encapsulated or hazardous payloads.  Without hazardous processing facility, SLS is limited to Orion.

I said "Cargo Processing and Preps", I said nothing about payload fueling or encapsulation.
There are the AstroTech facilities for that.
They also could do payload encapsulation in the old Shuttle Payload Canister Facility.
But, there is no rush to modify facilities to do so, as there are no SLS Cargo Payloads on the books.
Lots of "maybe" and "might happen", but nothing hard on the books at this time.
Title: Re: SLS General Discussion Thread 2
Post by: OV135 on 02/06/2016 10:39 PM
I've not been here in a while. I saw the new SLS images and wonder why they changed the core stage color from that deja vu of Saturn V to the shuttle ET foam covered current look?
Title: Re: SLS General Discussion Thread 2
Post by: Rocket Science on 02/06/2016 10:50 PM
I've not been here in a while. I saw the new SLS images and wonder why they changed the core stage color from that deja vu of Saturn V to the shuttle ET foam covered current look?
Save weight... ;)
Title: Re: SLS General Discussion Thread 2
Post by: rocx on 02/08/2016 10:41 AM
I've not been here in a while. I saw the new SLS images and wonder why they changed the core stage color from that deja vu of Saturn V to the shuttle ET foam covered current look?
The theory I've read most around here is that there never was a serious intention to paint the core stage white, but that it was shown that way in promotion materials to set it apart from the cancelled Ares V.
Title: Re: SLS General Discussion Thread 2
Post by: oldAtlas_Eguy on 02/12/2016 02:29 PM
Hmmm.

http://forum.nasaspaceflight.com/index.php?topic=31740.msg1490778#msg1490778 (http://forum.nasaspaceflight.com/index.php?topic=31740.msg1490778#msg1490778)

Using a simulation object with a ? as to its authentic size and placement of fittings as a fit check device of another set of equipment for an as yet created piece of hardware subject to changes (the SLS core) is not what I consider a good use of funds other than it could reduce the more obvious problems but none of the subtle ones. It is what you do if you are running behind schedule and you are trying to make up some time.
Title: Re: SLS General Discussion Thread 2
Post by: Endeavour_01 on 02/13/2016 03:06 AM

Using a simulation object with a ? as to its authentic size and placement of fittings as a fit check device of another set of equipment for an as yet created piece of hardware subject to changes (the SLS core) is not what I consider a good use of funds other than it could reduce the more obvious problems but none of the subtle ones. It is what you do if you are running behind schedule and you are trying to make up some time.

The SLS core design is basically locked in now. Why would it change?
Title: Re: SLS General Discussion Thread 2
Post by: the_other_Doug on 02/13/2016 01:22 PM

Using a simulation object with a ? as to its authentic size and placement of fittings as a fit check device of another set of equipment for an as yet created piece of hardware subject to changes (the SLS core) is not what I consider a good use of funds other than it could reduce the more obvious problems but none of the subtle ones. It is what you do if you are running behind schedule and you are trying to make up some time.

The SLS core design is basically locked in now. Why would it change?

There are always numerous, if relatively minor, alterations that occur to any design when metal starts being bent.  Even going from one block version of a vehicle to the next block version generally introduces numerous minor alterations.

That said, it's not like this is unprecedented in NASA rocket programs.  Recall that AS-500F was a full-scale mockup of the Saturn V vehicle, with all of the various connectors, plumbing leads, etc. that the real vehicle would have.  It allowed for the hands-on verification of the pad systems as well as electrical connectivity tests between the GSE and the dummy vehicle.  I don't believe that was wasted money.  However, even with all of those fit checks and procedures training that occurred on AS-500F, it still took three weeks to get through a four-day CDDT on the first actual flight vehicle, AS-501.  So, even with a dummy vehicle, nowhere near all of the learning curve was climbed working with the dummy vehicle.

Similarly, the shuttle Enterprise (an actual flight-configured vehicle in terms of its plumbing and electrical connections) was used for similar pad check-out purposes, with a dummy ET and dummy SRBs, after the A&LT program wound down.  And while that exercise was useful, there was still a lot of learning curve to climb when Columbia finally took its place on the pad to ready for flight.

I guess my point is that dummy vehicles (mockups) have been a part of NASA development for half a century or more.  And that such mockups are actually very useful, even after the design is pretty well frozen, to illustrate small changes still needed to the design (normally to interface positioning).  But they have never been the be-all and end-all of figuring out how everything will fit and work together, both on the pad and in flight.  So, the mockups aren't a waste of time or money, but by the same token they are not, and are never intended to be, completely identical to the real vehicles they are modeled on.

And the mockups are only useful after the final design has been pretty well frozen, but before major flight hardware has been built, so you don't find that, despite the way the specs have been reviewed, the main oxygen inlet fixture is somehow three inches lower and slightly to the right of where the main pad oxygen inlet plumbing has been positioned to connect to it (as a made-up example).  If the fix requires that the oxygen inlet on the rocket needs to be three inches higher up, then that change can be made on the as-yet-unbuilt flight hardware.  It's an awful lot more difficult to react to such situations if you wait until you have your flight hardware all built and find that you need to go back and scrap half of your stages because the inlet connections are all in a bad place.  Your only recourse at that point, really, is to kludge up the fittings in the pad hardware; enough of that and you have a bad, error-prone situation with your launch support systems.

There will always be a final learning curve to climb once you begin to fit together the actual flight stages and connect them to the pad hardware and GSE.  It would be an awfully lot higher curve to climb had they not gone through the mockup exercises, though...
Title: Re: SLS General Discussion Thread 2
Post by: oldAtlas_Eguy on 02/13/2016 07:19 PM
OK so these simulators are SOP for NASA and would be a normal part of any proposal and schedule for a NASA directed development.

Thanks for the info. Like I said it is useful for the obvious and as you mentioned it is highly useful in discovering when a procedure is in error. Procedures are less sensitive to minor design changes but very sensitive to the order of tasks. many order of tasks problems are not evident until you try to execute the procedures.
Title: Re: SLS General Discussion Thread 2
Post by: Hog on 03/02/2016 05:05 PM
I just wanted to put some perspective on the entire SLS program.

We are 18 months from the planned cryo tanking test, and 20 months from the "Green Run Hotfire" test of the entire EM-1 Core Stage on the B-2 test stand at Stennis Space Center.

Image #1-Shows a Saturn S1-C 1st stage being hoisted into the test stand at Stennis SC
Image #2-Shows a S1-C hotfire test in 1967 at Stennis
Image #3-Shows a Saturn-V S1-C 1st stage leaving Stennis bound for KSC for stacking and launching.  Just imagine in early 2018, the EM-1 core stage will be making a similar voyage on the Pegasus barge.
Image #4-Shows a SLS core stage installed in the B-2 test stand for the hotfiring of 4 RS-25 engines

We are about to enter the 2nd quarter of 2016. Projects SLS and Orion are all coming together.  I can hardly wait to see, hear and FEEL 4 RS-25s light off followed shortly thereafter by 2 of the largest rocket engines in the world.  This is really happening, and launch day is rapidly approaching. 

Good work, and good luck to all those involved!


(of course all scheduling is subject to change)
Title: Re: SLS General Discussion Thread 2
Post by: Robotbeat on 03/03/2016 02:51 AM
...as much as I point out SLS is a complete waste of money, I /will/ still be trying to attend the first launch because it will be quite spectacular. :)
Title: Re: SLS General Discussion Thread 2
Post by: RocketGoBoom on 03/04/2016 10:01 PM
The SLS/Orion mission to visit the asteroid in orbit around the moon is looking like it is going to be delayed and possibly cancelled.

It is already being delayed to "study".

http://spacenews.com/nasa-slips-schedule-of-asteroid-redirect-mission/
Title: Re: SLS General Discussion Thread 2
Post by: rayleighscatter on 03/10/2016 08:19 PM
Quote
On March 4, crew members ready a 900-pound steel beam to "top out" Test Stand 4697, which is under construction to test the Space Launch System liquid oxygen tank at NASA's Marshall Space Flight Center in Huntsville, Alabama. "Topping out" is a builders' rite traditionally held when the last beam is placed on top of a structure during its construction. The 85-foot-tall test stand will use hydraulic cylinders to subject the liquid oxygen tank and hardware of the massive SLS core stage to the same loads and stresses it will endure during a launch. The tests also will verify the models already in place that predict the amount of loads the core stage can withstand during launch and ascent. Prime contractor Brasfield & Gorrie of Birmingham, Alabama, and several of its subcontractors are constructing Test Stand 4697 and Test Stand 4693, which will have a twin-tower configuration and conduct similar structural tests on the SLS core stage's liquid hydrogen tank. Both stands are scheduled to be completed later this year. SLS will be the world's most powerful rocket and carry astronauts in NASA's Orion spacecraft on deep-space missions, including the journey to Mars.
Title: Re: SLS General Discussion Thread 2
Post by: daveklingler on 03/11/2016 08:35 PM

Using a simulation object with a ? as to its authentic size and placement of fittings as a fit check device of another set of equipment for an as yet created piece of hardware subject to changes (the SLS core) is not what I consider a good use of funds other than it could reduce the more obvious problems but none of the subtle ones. It is what you do if you are running behind schedule and you are trying to make up some time.

The SLS core design is basically locked in now. Why would it change?

Has anyone here examined the possibility of an SLS first stage powered by AR-1 or BE-4 engines?  :)

Switching wouldn't change the timeframe that much, and it would drop the first stage cost by, oh...$200-250M, at a WAG.
Title: Re: SLS General Discussion Thread 2
Post by: The Amazing Catstronaut on 03/11/2016 09:55 PM

Switching wouldn't change the timeframe that much...

Sure would - the first stage engines are one of the most pivotal, complex elements of the whole LV. You switch those out and you have to change the whole design, especially when you're talking different fuel types. We're talking about a rocket that'd be as different as SLS is from Aries V. There's a reason why Vulcan is massively different to merely a "re-engined Atlas V" as some community elements conceived it would be. Structure, tanking, tolerances, thermodynamics, stresses, aerodynamics, everything changes, mass, acceleration on ascent,  staging time, everything changes, everything must be recalculated, resimulated, reengineered, retested. You'd end up spending way more money than you'd save in infrastructure changes alone.

If SLS was re-engined, it'd die.

Boosters are a little bit different, but still a major element.
Title: Re: SLS General Discussion Thread 2
Post by: MATTBLAK on 03/11/2016 10:06 PM
The SLS/Orion mission to visit the asteroid in orbit around the moon is looking like it is going to be delayed and possibly cancelled.

It is already being delayed to "study".

http://spacenews.com/nasa-slips-schedule-of-asteroid-redirect-mission/

They should put a small Habitat Module out there to test radiation mitigation, life support systems and other tech. The crew could dock with it and do a "This is what going to Mars is going to feel like".
Title: Re: SLS General Discussion Thread 2
Post by: Proponent on 03/12/2016 08:00 AM
Not only would changing engines be technically difficult at this stage, as The Amazing Catstronaut says, but using the BE-4 would be politically difficult, as it would seriously hurt one of the major inhabitants of the Shuttle ecosystem, namely Aerojet Rocketdyne.

It might be interesting to wonder, though, where things might have gone had the AR-1 been on the drawing board circa 2011, when the RAC teams were doing their studies.
Title: Re: SLS General Discussion Thread 2
Post by: jgoldader on 03/12/2016 11:00 AM
The SLS/Orion mission to visit the asteroid in orbit around the moon is looking like it is going to be delayed and possibly cancelled.

It is already being delayed to "study".

http://spacenews.com/nasa-slips-schedule-of-asteroid-redirect-mission/

I've been expecing at least some discussion here about the elephant in the room that the "delay" represents, but am surprised/not surprised it hasn't started yet.
Title: Re: SLS General Discussion Thread 2
Post by: edkyle99 on 03/12/2016 04:50 PM

Switching wouldn't change the timeframe that much...

Sure would - the first stage engines are one of the most pivotal, complex elements of the whole LV. You switch those out and you have to change the whole design, especially when you're talking different fuel types. ...
Precisely.  If SLS went to a lower-performing hydrocarbon core first stage, a heavier, higher thrust second stage would be needed.  It would mean bringing back J-2X.  It would also mean development of a smaller in-space third stage.

These questions were all studied to death a decade ago.  Multiple studies of innumerable alternative designs.  The best answer nearly every time looked pretty much like the rocket now being built.

 - Ed Kyle
Title: Re: SLS General Discussion Thread 2
Post by: the_other_Doug on 03/12/2016 04:59 PM

Switching wouldn't change the timeframe that much...

Sure would - the first stage engines are one of the most pivotal, complex elements of the whole LV. You switch those out and you have to change the whole design, especially when you're talking different fuel types. ...
Precisely.  If SLS went to a lower-performing hydrocarbon core first stage, a heavier, higher thrust second stage would be needed.  It would mean bringing back J-2X.  It would also mean development of a smaller in-space third stage.

 - Ed Kyle

Yeah -- if you're going to change to kerolox or metholox in the SLS first stage, you might just as well pull out the old plans and start building Saturn V's again...
Title: Re: SLS General Discussion Thread 2
Post by: Coastal Ron on 03/12/2016 07:50 PM
I've been expecing at least some discussion here about the elephant in the room that the "delay" represents, but am surprised/not surprised it hasn't started yet.

That's because it wasn't a surprise, it was expected.
Title: Re: SLS General Discussion Thread 2
Post by: daveklingler on 03/13/2016 01:50 AM
First of all, I think it's (over)stating the obvious to say that changing SLS engines at this point would create a few raised eyebrows.  My first take was that it would cause the biggest agency crisis since Apollo I.  Then I thought about it.  Hm.  NASA got away with "redesigning" the J-2 as the J-2X, and the Senate got away with designing a heavy lift rocket that NASA can't afford to fly.  Possibly a switch to the AR-1 might be billed as an "engine upgrade".  I'm laughing ruefully as I write this, and remembering more examples where the truth as been, ahem, finessed.


Switching wouldn't change the timeframe that much...

Sure would - the first stage engines are one of the most pivotal, complex elements of the whole LV. You switch those out and you have to change the whole design, especially when you're talking different fuel types. ...
Precisely.  If SLS went to a lower-performing hydrocarbon core first stage, a heavier, higher thrust second stage would be needed.  It would mean bringing back J-2X.  It would also mean development of a smaller in-space third stage.

These questions were all studied to death a decade ago.  Multiple studies of innumerable alternative designs.  The best answer nearly every time looked pretty much like the rocket now being built.

 - Ed Kyle

You have more faith than I do that the best answer, a decade ago or any other time, was to design a hydrolox first stage with solid boosters and Shuttle engines.  Besides, the AR-1 didn't exist back then.  Today, Congress is every bit as bent on bringing the AR-1 into existence as they were the J-2X and SLS. Whether, given the chance, AJR wouldn't choose a long-term commitment for AR-1 is an interesting question.

Beyond that, all of this was relitigated after 2010, and stayed fuzzy into well into 2012, after which it still creaked along before and after PDR in mid-2013.  Quite frankly, I'd give it roughly six months to get back to PDR on a new kerolox first stage, using the work that's been done already.  The rest of the vehicle is clearly-parameterized.  Many other choices wouldn't be need to be made over again, saving more time before a first CDR.

Regarding your assertion that the new first stage would be lower-performance, the tank mass and fuel density difference along with the relatively low difference (~50 seconds) in sea level Isp generally makes kerolox come out slightly better for first stages, which I'm pretty sure you know very well.

I think an AR-1 first stage is worth putzing around with.  I'm not seriously proposing any of this could ever come about, ever ever ever, but stranger things have happened.  After all, the Senate designed a rocket...

*edit - And then, there's the AR-1/SLS common booster core...  :D
Title: Re: SLS General Discussion Thread 2
Post by: daveklingler on 03/13/2016 02:09 AM
Not only would changing engines be technically difficult at this stage, as The Amazing Catstronaut says, but using the BE-4 would be politically difficult, as it would seriously hurt one of the major inhabitants of the Shuttle ecosystem, namely Aerojet Rocketdyne.

Given the SLS's sole purpose of supporting that ecosystem, the BE-4 is an even less likely design choice, I admit.

Quote
It might be interesting to wonder, though, where things might have gone had the AR-1 been on the drawing board circa 2011, when the RAC teams were doing their studies.

Yep.  Or where things might have gone had an AR-1 been funded over a decade back instead of the J-2X.
Title: Re: SLS General Discussion Thread 2
Post by: Endeavour_01 on 03/13/2016 02:13 AM
...as much as I point out SLS is a complete waste of money, I /will/ still be trying to attend the first launch because it will be quite spectacular. :)

While we disagree on whether SLS is a waste or not I share your desire to see the first launch. Hopefully job situation will allow (If I can land a teaching job after graduation I will make it a field trip!). We definitely need to have an NSF group get together to see the launch (and the first manned CST-100 and Dragon launches).

They should put a small Habitat Module out there to test radiation mitigation, life support systems and other tech. The crew could dock with it and do a "This is what going to Mars is going to feel like".

That would be the best thing to do for EM-3 in my view. NASA already has Congressional authorization and funds to start working on a habitat module. There would be plenty of time to get it ready and we would get a foothold in cislunar space.
Title: Re: SLS General Discussion Thread 2
Post by: A_M_Swallow on 03/13/2016 03:26 AM
First of all, I think it's (over)stating the obvious to say that changing SLS engines at this point would create a few raised eyebrows.  My first take was that it would cause the biggest agency crisis since Apollo I.  Then I thought about it.  Hm.  NASA got away with "redesigning" the J-2 as the J-2X, and the Senate got away with designing a heavy lift rocket that NASA can't afford to fly.  Possibly a switch to the AR-1 might be billed as an "engine upgrade".  I'm laughing ruefully as I write this, and remembering more examples where the truth as been, ahem, finessed.

{snip}

The first few engines are literally the Space Shuttle engines. These will soon run out. After that NASA will have to buy newly manufactured engines either more of the same design or a new design. A new design of engine would have to have a bigger payload, be more efficient, available sooner or cheaper.
Title: Re: SLS General Discussion Thread 2
Post by: Eric Hedman on 03/13/2016 05:26 AM
First of all, I think it's (over)stating the obvious to say that changing SLS engines at this point would create a few raised eyebrows.  My first take was that it would cause the biggest agency crisis since Apollo I.  Then I thought about it.  Hm.  NASA got away with "redesigning" the J-2 as the J-2X, and the Senate got away with designing a heavy lift rocket that NASA can't afford to fly.  Possibly a switch to the AR-1 might be billed as an "engine upgrade".  I'm laughing ruefully as I write this, and remembering more examples where the truth as been, ahem, finessed.

{snip}

The first few engines are literally the Space Shuttle engines. These will soon run out. After that NASA will have to buy newly manufactured engines either more of the same design or a new design. A new design of engine would have to have a bigger payload, be more efficient, available sooner or cheaper.
I thought NASA awarded Aerojet Rocketdyne a contract back in November to modernize the RS-25 and restart production.
Title: Re: SLS General Discussion Thread 2
Post by: RonM on 03/13/2016 01:29 PM
First of all, I think it's (over)stating the obvious to say that changing SLS engines at this point would create a few raised eyebrows.  My first take was that it would cause the biggest agency crisis since Apollo I.  Then I thought about it.  Hm.  NASA got away with "redesigning" the J-2 as the J-2X, and the Senate got away with designing a heavy lift rocket that NASA can't afford to fly.  Possibly a switch to the AR-1 might be billed as an "engine upgrade".  I'm laughing ruefully as I write this, and remembering more examples where the truth as been, ahem, finessed.

{snip}

The first few engines are literally the Space Shuttle engines. These will soon run out. After that NASA will have to buy newly manufactured engines either more of the same design or a new design. A new design of engine would have to have a bigger payload, be more efficient, available sooner or cheaper.
I thought NASA awarded Aerojet Rocketdyne a contract back in November to modernize the RS-25 and restart production.

You are correct.

https://www.nasaspaceflight.com/2016/01/nasa-defends-restart-rs-25-production/
Title: Re: SLS General Discussion Thread 2
Post by: edkyle99 on 03/13/2016 03:17 PM

Regarding your assertion that the new first stage would be lower-performance, the tank mass and fuel density difference along with the relatively low difference (~50 seconds) in sea level Isp generally makes kerolox come out slightly better for first stages, which I'm pretty sure you know very well.
I think you know pretty well that the SLS core stage is not a "first stage".  It is a long-burning sustainer stage serving the same purpose as the Orbiter/ET combination.  It provides high specific impulse above all else, much higher than only "~50 seconds" since most of its action time is in vacuum where its advantage over a hydrocarbon engine is in excess of 120 seconds ISP.  It only needs enough thrust to keep positive T/W after the SRBs stop thrusting.

If you replace this high-performing core stage with a hydrocarbon stage, you are going to have to make up the delta-v shortfall with a bigger, more expensive LOX/LH2 upper stage which will require higher thrust than RL10 and the like can provide.  All of the studies showed that result.  The proper application of a hydrocarbon engine would be as part of an SRB replacement.

 - Ed Kyle
Title: Re: SLS General Discussion Thread 2
Post by: Space Ghost 1962 on 03/13/2016 03:30 PM
The proper application of a hydrocarbon engine would be as part of an SRB replacement.
Actually, the only application.
Title: Re: SLS General Discussion Thread 2
Post by: AncientU on 03/13/2016 06:32 PM
The proper application of a hydrocarbon engine would be as part of an SRB replacement.
Actually, the only application.

Unless a hydrocarbon core stage replaces the entire SLS, of course.
Title: Re: SLS General Discussion Thread 2
Post by: TomH on 03/13/2016 08:04 PM
None of these options is under the slightest consideration. Join L2 for the definitive status of SLS. The elephant mastodon in the room is indeed a hydrocarbon fueled 15m diameter monster which will be affordable due to leaner manufacturing processes, the lack of government involvement, and most of all, reusability.
Title: Re: SLS General Discussion Thread 2
Post by: MATTBLAK on 03/13/2016 08:08 PM
I will certainly believe it when I certainly see it.
Title: Re: SLS General Discussion Thread 2
Post by: oldAtlas_Eguy on 03/13/2016 08:26 PM
Do not forget SLS is a political beast. Congress can change their minds as to what they want. As in a 200+mt launcher for Mars not just a 100mt maybe a 130mt launcher. Such as liquid boosters, 5 engine RS-68A core, J-2X second stage and a RL-10 EDS. Plus use something else (commercial LV) to get Orion into LEO where it docks with the rest of the Mars stack. Constellation resurrected.
Title: Re: SLS General Discussion Thread 2
Post by: A_M_Swallow on 03/13/2016 09:06 PM
First of all, I think it's (over)stating the obvious to say that changing SLS engines at this point would create a few raised eyebrows.  My first take was that it would cause the biggest agency crisis since Apollo I.  Then I thought about it.  Hm.  NASA got away with "redesigning" the J-2 as the J-2X, and the Senate got away with designing a heavy lift rocket that NASA can't afford to fly.  Possibly a switch to the AR-1 might be billed as an "engine upgrade".  I'm laughing ruefully as I write this, and remembering more examples where the truth as been, ahem, finessed.

{snip}

The first few engines are literally the Space Shuttle engines. These will soon run out. After that NASA will have to buy newly manufactured engines either more of the same design or a new design. A new design of engine would have to have a bigger payload, be more efficient, available sooner or cheaper.
I thought NASA awarded Aerojet Rocketdyne a contract back in November to modernize the RS-25 and restart production.

That is a factual argument not a political argument.

Although it is why NASA went that way.
Title: Re: SLS General Discussion Thread 2
Post by: Space Ghost 1962 on 03/13/2016 10:46 PM
Sure they can moot many things, some that might even get study financing. Longer term depends on many things, and they can be reversed at times too.

The SLS that appears to not be paper might do missions. The capability to do missions in less than an decade will fight with the paper design to get out of the box that must take more decades - govt related work often takes a lot longer.

Depending on outside of government "deals" might sound "quicker", but these are always subject to changing political trades that may never resolve.
Title: Re: SLS General Discussion Thread 2
Post by: Robotbeat on 03/13/2016 11:39 PM
None of these options is under the slightest consideration. Join L2 for the definitive status of SLS. The elephant mastodon in the room is indeed a hydrocarbon fueled 15m diameter monster which will be affordable due to leaner manufacturing processes, the lack of government involvement, and most of all, reusability.
...and only needing to be 2 stages. Vs 2 boosters, 1 core, and an upper stage. And the 2nd stage of the mastadon would also be your lander/ascender, which is honestly just as important as the launch vehicle.

...anyway, there was definitely a small cadre of people pushing for a return to a big kerolox core, but they lost out to the Shuttle-derived folk.
Title: Re: SLS General Discussion Thread 2
Post by: EE Scott on 03/14/2016 12:40 AM

...snip...

These questions were all studied to death a decade ago.  Multiple studies of innumerable alternative designs.  The best answer nearly every time looked pretty much like the rocket now being built.

 - Ed Kyle

This is not a helpful description. The "best answer" was pushed into view by folks who in my opinion appeared highly politically biased. Does the idea of black zones or perhaps the name Michael Griffin not bring back any memories of those days? If I am remembering that time inaccurately, please let me know.
Title: Re: SLS General Discussion Thread 2
Post by: Oli on 03/14/2016 09:59 AM

...snip...

These questions were all studied to death a decade ago.  Multiple studies of innumerable alternative designs.  The best answer nearly every time looked pretty much like the rocket now being built.

 - Ed Kyle

This is not a helpful description. The "best answer" was pushed into view by folks who in my opinion appeared highly politically biased. Does the idea of black zones or perhaps the name Michael Griffin not bring back any memories of those days? If I am remembering that time inaccurately, please let me know.

So NASA faked their own cost estimates? SLS is a good TLI launcher and it was considered cheaper in development than the alternatives. Back in 2010.

Title: Re: SLS General Discussion Thread 2
Post by: notsorandom on 03/14/2016 01:14 PM
It only needs enough thrust to keep positive T/W after the SRBs stop thrusting.
This may be a pretty minor nitpick. The Shuttle had a T/W lower than 1:1 at SRB separation. Isn't the same true of SLS?
Title: Re: SLS General Discussion Thread 2
Post by: edkyle99 on 03/14/2016 02:20 PM

...snip...

These questions were all studied to death a decade ago.  Multiple studies of innumerable alternative designs.  The best answer nearly every time looked pretty much like the rocket now being built.

 - Ed Kyle

This is not a helpful description. The "best answer" was pushed into view by folks who in my opinion appeared highly politically biased. Does the idea of black zones or perhaps the name Michael Griffin not bring back any memories of those days? If I am remembering that time inaccurately, please let me know.
"Black Zones"?  That had nothing to do with SLS.  Michael Griffin?  He was gone before SLS was defined. 

A series of studies, including the substantial "Requirements Analyses Cycle", were performed during 2010-2011, months after President Obama sent Griffin packing.  Saturn V-like RP/LOX first stages were considered, but the development costs were an issue.  ORSC and J-2X would have been required.  SLS won in part because the propulsion existed, or nearly existed, minimizing development cost.  NASA can hardly afford SLS as it is.  It never would have been able to fund a full-up new propulsion development effort. 

 - Ed Kyle
Title: Re: SLS General Discussion Thread 2
Post by: EE Scott on 03/14/2016 02:38 PM

...snip...

These questions were all studied to death a decade ago.  Multiple studies of innumerable alternative designs.  The best answer nearly every time looked pretty much like the rocket now being built.

 - Ed Kyle

This is not a helpful description. The "best answer" was pushed into view by folks who in my opinion appeared highly politically biased. Does the idea of black zones or perhaps the name Michael Griffin not bring back any memories of those days? If I am remembering that time inaccurately, please let me know.
"Black Zones"?  That had nothing to do with SLS.  Michael Griffin?  He was gone before SLS was defined. 

A series of studies, including the substantial "Requirements Analyses Cycle", were performed during 2010-2011, months after President Obama sent Griffin packing.  Saturn V-like RP/LOX first stages were considered, but the development costs were an issue.  ORSC and J-2X would have been required.  SLS won in part because the propulsion existed, or nearly existed, minimizing development cost.  NASA can hardly afford SLS as it is.  It never would have been able to fund a full-up new propulsion development effort. 

 - Ed Kyle

Good points. I was not thinking about the RAC studies, I thought you were referencing ESAS, etc., when you stated that this issue was studied to death a decade ago, which I took to mean that you are stating that any doubts about the superiority of SDLV solutions vs. non-SDLV for NASA's manned BEO program was basically put to bed long ago.
Title: Re: SLS General Discussion Thread 2
Post by: EE Scott on 03/14/2016 02:40 PM

...snip...

These questions were all studied to death a decade ago.  Multiple studies of innumerable alternative designs.  The best answer nearly every time looked pretty much like the rocket now being built.

 - Ed Kyle

This is not a helpful description. The "best answer" was pushed into view by folks who in my opinion appeared highly politically biased. Does the idea of black zones or perhaps the name Michael Griffin not bring back any memories of those days? If I am remembering that time inaccurately, please let me know.

So NASA faked their own cost estimates? SLS is a good TLI launcher and it was considered cheaper in development than the alternatives. Back in 2010.



No I don't mean to imply that, sorry if it came off that way. I wasn't thinking specifically of SLS.
Title: Re: SLS General Discussion Thread 2
Post by: edkyle99 on 03/14/2016 02:43 PM
It only needs enough thrust to keep positive T/W after the SRBs stop thrusting.
This may be a pretty minor nitpick. The Shuttle had a T/W lower than 1:1 at SRB separation. Isn't the same true of SLS?
At SRB sep, STS T/W was probably 0.91-0.93 or thereabouts, so generally speaking the design was for a nearly 1:1 ratio at staging.  T/W went positive within 15-20 seconds and of course remained positive for the subsequent ~355 seconds of the SSME burn.  I'm not sure about SLS at the moment, but I would expect it to also be ballpark 1:1.

 - Ed Kyle
Title: Re: SLS General Discussion Thread 2
Post by: TomH on 03/14/2016 03:35 PM
It only needs enough thrust to keep positive T/W after the SRBs stop thrusting.
This may be a pretty minor nitpick. The Shuttle had a T/W lower than 1:1 at SRB separation. Isn't the same true of SLS?

If you were doing a perfectly vertical shot toward GSO or escape, that ratio would cause gravity losses which are greater than acceleration. The thing is, the W part of that T/W is a function of gravity times mass. When you factor your velocity into separate vectors according to your trajectory, some of the V is vertical climb and some of it is downrange velocity. The downrange velocity is canceling out part of the gravitational pull. Sitting on the ground, mass and weight are equal. Once you are in a semi-orbital trajectory, the weight is less than the mass, so what seems to be < 1:1 ratio actually is not.

Think about STS. At main tank separation, there is not enough velocity for orbit. The tank reenters and burns up. The thrust of the two OMS engines is technically far less than 1:1 T/W if you are considering the mass of the vehicle to also be the weight of the vehicle. However, because the vehicle is almost in orbit, the forward velocity is cancelling out almost all of the pull of gravity (and remember, weight is a function of mass times gravity). So though the mass is still pretty much the same, the weight is now much lower. The low thrust OMS engines are quite adequate to increase the velocity to orbital velocity.

The same thing is true after SRB separation. The downrange velocity is cancelling part of the effect of gravity, so the weight is actually lower than the mass and the T/W is greater than 1.
Title: Re: SLS General Discussion Thread 2
Post by: oldAtlas_Eguy on 03/14/2016 03:43 PM

...snip...

These questions were all studied to death a decade ago.  Multiple studies of innumerable alternative designs.  The best answer nearly every time looked pretty much like the rocket now being built.

 - Ed Kyle

This is not a helpful description. The "best answer" was pushed into view by folks who in my opinion appeared highly politically biased. Does the idea of black zones or perhaps the name Michael Griffin not bring back any memories of those days? If I am remembering that time inaccurately, please let me know.

So NASA faked their own cost estimates? SLS is a good TLI launcher and it was considered cheaper in development than the alternatives. Back in 2010.



No I don't mean to imply that, sorry if it came off that way. I wasn't thinking specifically of SLS.
In order to understand the "best" of the study, you must also investigate what were the assumptions made for the  evaluation models. These assumptions can create their own set of biases funneling you to a specific design as best when it is not. SpaceX is obviously using a different set of assumptions in their models to determine "best" that result in the BFR/MCT configuration. Each different set of assumptions result in a different "best".

SLS was a separate beast in that the two main "best" concerns controlling its design was development costs and schedule. Actually schedule may have been the more important item of the two. A $15B development cost (the SLS will not be operational until EM-2, $1.5B/yr for 10 years) I would not consider an inexpensive development.
Title: Re: SLS General Discussion Thread 2
Post by: Lobo on 03/14/2016 04:16 PM

Switching wouldn't change the timeframe that much...

Sure would - the first stage engines are one of the most pivotal, complex elements of the whole LV. You switch those out and you have to change the whole design, especially when you're talking different fuel types. ...
Precisely.  If SLS went to a lower-performing hydrocarbon core first stage, a heavier, higher thrust second stage would be needed.  It would mean bringing back J-2X.  It would also mean development of a smaller in-space third stage.

These questions were all studied to death a decade ago.  Multiple studies of innumerable alternative designs.  The best answer nearly every time looked pretty much like the rocket now being built.

 - Ed Kyle

Not quite sure I agree with you here Ed (which is rare, I usually do).

If you mean a decade ago during the ESAS study, I think there were much better options considered (and some not considered) , and then passed up on in favor of basically what's being built now in LV 27.3 (not, exactly, but pretty similar)

By the time we were at CxP's cancellation about 5 years ago, then I think you are correct, what they are building now is probably about the best configuration, given politics, that could be expected.
Title: Re: SLS General Discussion Thread 2
Post by: Lobo on 03/14/2016 04:22 PM

In order to understand the "best" of the study, you must also investigate what were the assumptions made for the  evaluation models. These assumptions can create their own set of biases funneling you to a specific design as best when it is not. SpaceX is obviously using a different set of assumptions in their models to determine "best" that result in the BFR/MCT configuration. Each different set of assumptions result in a different "best".


Good point. 

I think a lot of the appearance of a "thumb on the scale" of the result of the ESAS study was based on many assumptions by NASA that seemed to be perhaps somewhat unreasonable.   In order to force LV13.1 and 27.3 as the winners, where seemingly there were better options passed up.

Title: Re: SLS General Discussion Thread 2
Post by: daveklingler on 03/14/2016 07:32 PM

Regarding your assertion that the new first stage would be lower-performance, the tank mass and fuel density difference along with the relatively low difference (~50 seconds) in sea level Isp generally makes kerolox come out slightly better for first stages, which I'm pretty sure you know very well.
I think you know pretty well that the SLS core stage is not a "first stage".  It is a long-burning sustainer stage serving the same purpose as the Orbiter/ET combination.  It provides high specific impulse above all else, much higher than only "~50 seconds" since most of its action time is in vacuum where its advantage over a hydrocarbon engine is in excess of 120 seconds ISP.  It only needs enough thrust to keep positive T/W after the SRBs stop thrusting.

If you replace this high-performing core stage with a hydrocarbon stage, you are going to have to make up the delta-v shortfall with a bigger, more expensive LOX/LH2 upper stage which will require higher thrust than RL10 and the like can provide.  All of the studies showed that result.  The proper application of a hydrocarbon engine would be as part of an SRB replacement.

 - Ed Kyle

I'm trying to avoid blowing an evening with my calculator in an attempt to verify something which only matters as an intellectual exercise.  :)  I did, unfortunately, blow an hour already trying to find decent numbers for the various SLS components, along with an ascent profile, before giving up.

Anyway, without a side booster configuration, I think you'd be very obviously right.  But with a side booster configuration, my intuition is that an ORSC core could be configured in such a way that there would be no delta vee shortfall for the EUS to make up.  I think such an "upgrade" would be faster and easier if the boosters were liquid, and I suspect that with something like a 7xORSC common core for both boosters and center the end result would be quite capable and minimally disruptive.

That's all guesswork.  I'm having fun playing hookey, but I don't dare take a day off to figure out whether it's all impossible.
Title: Re: SLS General Discussion Thread 2
Post by: daveklingler on 03/14/2016 07:44 PM
SLS won in part because the propulsion existed, or nearly existed, minimizing development cost.  NASA can hardly afford SLS as it is.  It never would have been able to fund a full-up new propulsion development effort. 

My whole point is that it's interesting to contemplate the new possibilities.  Essentially, the lack of any decent hydrocarbon engine a few short years ago has completely changed through the grace of a billionaire and some politicians.  Where the AR-1 is concerned, Congress has essentially reached into the Air Force budget to create something which currently has no useful purpose.  Voila, a relatively cheap (putatively $12.5M) ORSC engine!  What can be done with it?
Title: Re: SLS General Discussion Thread 2
Post by: Prettz on 03/14/2016 07:59 PM
What was so wrong with using the F-1B?
Title: Re: SLS General Discussion Thread 2
Post by: Coastal Ron on 03/14/2016 08:32 PM
SLS won in part because the propulsion existed, or nearly existed, minimizing development cost.

It was pretty much a foregone conclusion that the SLS would use what is being used today, since the law Congress wrote pretty much said that NASA must, per Sec. 304 (a) (1), to the extent practicable, use:

"(B) Space Shuttle-derived components and Ares 1 components that use existing United States propulsion systems, including liquid fuel engines, external tank or tank- related capability, and solid rocket motor engines; and (2) associated testing facilities, either in being or under construction as of the date of enactment of this Act."

Plus the quick need dates:

"Priority should be placed on the core elements with the goal for operational capability for the core elements not later than December 31, 2016."

And I'm sure we all recall the many in the space community that wondered why NASA was "dragging it's feet" taking so long to define the SLS.  NASA tried to make it look like they had a choice on the design, but Congress didn't give them enough room to really have any choice.

Quote
NASA can hardly afford SLS as it is.

The cost of development is not the real issue.  The cost of using an HLV every year, for decades, is the real question.  And no one knows the answer to that...
Title: Re: SLS General Discussion Thread 2
Post by: Zed_Noir on 03/15/2016 04:22 AM

Quote
NASA can hardly afford SLS as it is.

The cost of development is not the real issue.  The cost of using an HLV every year, for decades, is the real question.  And no one knows the answer to that...

Bah. The folks from Hawthorne will make that moot one way or another soon. Either with the soom to debut HLV lite or the Mastodon SHLV to be announced in September. Either the HLV lite or the SHLV will likely to have at least half a dozen flights per year once in service.
Title: Re: SLS General Discussion Thread 2
Post by: Steven Pietrobon on 03/15/2016 04:55 AM
This may be a pretty minor nitpick. The Shuttle had a T/W lower than 1:1 at SRB separation. Isn't the same true of SLS?

For Block IB, its just under 1g at SRB separation. Actual acceleration is 9.5 m/s².
Title: Re: SLS General Discussion Thread 2
Post by: daveklingler on 03/15/2016 05:15 AM
What was so wrong with using the F-1B?

Congress has determined that the AR-1 shall exist, ye, verily.

That's not to rule out a future such decree on behalf of the F-1B, which I think would have given me more joy, as arbitrary declarations go. Perhaps when SpaceX and/or Blue get around to fielding a really great big rocket, Congress will hold hearings on why the USA doesn't have one yet.
Title: Re: SLS General Discussion Thread 2
Post by: notsorandom on 03/15/2016 02:07 PM
This may be a pretty minor nitpick. The Shuttle had a T/W lower than 1:1 at SRB separation. Isn't the same true of SLS?

For Block IB, its just under 1g at SRB separation. Actual acceleration is 9.5 m/s².
Thanks. The minute after I posted that I was wondering if there would be a difference because of the lighter ICPS.
Title: Re: SLS General Discussion Thread 2
Post by: AncientU on 03/15/2016 02:37 PM
What was so wrong with using the F-1B?

Congress has determined that the AR-1 shall exist, ye, verily.

That's not to rule out a future such decree on behalf of the F-1B, which I think would have given me more joy, as arbitrary declarations go. Perhaps when SpaceX and/or Blue get around to fielding a really great big rocket, Congress will hold hearings on why the USA doesn't have one yet.

USA will have two (or three, if VulcanHeavy is built, too) -- Congress will have to decide whether to follow their own law, or change it to keep their pet project(s) relevant.

To the maximum extent practicable, the Federal Government shall plan missions to accommodate the space transportation services capabilities of United States commercial providers. US law http://goo.gl/YZYNt0
-- Robotbeat's signature line

NOTE: The USG is not the USA.
Title: Re: SLS General Discussion Thread 2
Post by: Carl G on 03/15/2016 04:02 PM
Let's try and keep the politics out of this thread. In fact, let's do more than try, let's not.
Title: Re: SLS General Discussion Thread 2
Post by: daveklingler on 03/15/2016 04:44 PM
For Block IB, its just under 1g at SRB separation. Actual acceleration is 9.5 m/s².

Steven, are you set up to easily simulate an AR-1-based SLS?  I'm assuming you've long since set up a spreadsheet, since you've done several simulations at this point.
Title: Re: SLS General Discussion Thread 2
Post by: daveklingler on 03/15/2016 04:46 PM
What was so wrong with using the F-1B?

Congress has determined that the AR-1 shall exist, ye, verily.

That's not to rule out a future such decree on behalf of the F-1B, which I think would have given me more joy, as arbitrary declarations go. Perhaps when SpaceX and/or Blue get around to fielding a really great big rocket, Congress will hold hearings on why the USA doesn't have one yet.

USA will have two (or three, if VulcanHeavy is built, too) -- Congress will have to decide whether to follow their own law, or change it to keep their pet project(s) relevant.

To the maximum extent practicable, the Federal Government shall plan missions to accommodate the space transportation services capabilities of United States commercial providers. US law http://goo.gl/YZYNt0
-- Robotbeat's signature line

NOTE: The USG is not the USA.

I was attempting to be sardonic.
Title: Re: SLS General Discussion Thread 2
Post by: The Amazing Catstronaut on 03/15/2016 07:07 PM
Do not forget SLS is a political beast. Congress can change their minds as to what they want. As in a 200+mt launcher for Mars not just a 100mt maybe a 130mt launcher. Such as liquid boosters, 5 engine RS-68A core, J-2X second stage and a RL-10 EDS. Plus use something else (commercial LV) to get Orion into LEO where it docks with the rest of the Mars stack. Constellation resurrected.

They sure can, but it won't stay that way if it takes forever.  Sending SLS skyward is taking the best side of forever anyway, due to all the little nuances which need to be worked out before the twenty twenties (or 2018 for all of us in ESA funding nations/s). A changed congress may not be sympathetic to SLS either. Sure, they want a jobs program, but they also want to look competent and that they're at least attempting to use government funds efficiently.

Constellation architectures are not a paragon of efficiency, cost saving or even mission capability. There's better alternatives that can be done with either a leaner, skimpier architecture, or by going more massive and less. Either option contains higher prospective dollar value than Constellation.

Title: Re: SLS General Discussion Thread 2
Post by: Steven Pietrobon on 03/16/2016 03:07 AM
Steven, are you set up to easily simulate an AR-1-based SLS?  I'm assuming you've long since set up a spreadsheet, since you've done several simulations at this point.

Its relatively easy, but each simulation takes me half a day to perform. I use my own custom coded Pascal software. Its not a spreadsheet. I have already simulated liquid boosters with three AJ1E6 dual nozzle engines. I could use that to simulate six AR-1 engines.
Title: Re: SLS General Discussion Thread 2
Post by: TomH on 03/16/2016 04:03 PM
Steven, are you set up to easily simulate an AR-1-based SLS?  I'm assuming you've long since set up a spreadsheet, since you've done several simulations at this point.

Its relatively easy, but each simulation takes me half a day to perform. I use my own custom coded Pascal software. Its not a spreadsheet. I have already simulated liquid boosters with three AJ1E6 dual nozzle engines. I could use that to simulate six AR-1 engines.

I could be mistaken, but I think he means AR-1 on the core, not AR-1 boosters.
Title: Re: SLS General Discussion Thread 2
Post by: daveklingler on 03/18/2016 01:22 AM
Steven, are you set up to easily simulate an AR-1-based SLS?  I'm assuming you've long since set up a spreadsheet, since you've done several simulations at this point.

Its relatively easy, but each simulation takes me half a day to perform. I use my own custom coded Pascal software. Its not a spreadsheet. I have already simulated liquid boosters with three AJ1E6 dual nozzle engines. I could use that to simulate six AR-1 engines.

I could be mistaken, but I think he means AR-1 on the core, not AR-1 boosters.

I did mean the core, but I recognize that the boosters have a slightly better chance of seeing AR-1s than the core does.  It sounds like you're saying that the code you already wrote is applicable to either one?

I just found your 2013 SLS/F1B/AJ1E6 paper and reread it.  It seems like you might be able to take AJR at their word and basically plug in RD-180s, since they have said emphatically that they are doing their best to duplicate the RD-180 in every significant way.  I don't think they can come in much less or much above the RD-180's thrust level, nor can the Isp vary much, which means identical chamber size and pressure, bell dimensions, etc. Somewhere I did see something to the effect that every significant physical aspect of the RD-180 has been copied.

So in other words, you might be able to use an RD-180 in simulations.  Not sure whether that helps.  :)
Title: Re: SLS General Discussion Thread 2
Post by: Steven Pietrobon on 03/18/2016 05:41 AM
I did mean the core, but I recognize that the boosters have a slightly better chance of seeing AR-1s than the core does.  It sounds like you're saying that the code you already wrote is applicable to either one?

OK, I misunderstood and thought you were thinking of the boosters. I could also use AR-1's on the core, although this might require a bit more changing of the code.

Quote
I just found your 2013 SLS/F1B/AJ1E6 paper and reread it.  It seems like you might be able to take AJR at their word and basically plug in RD-180s, since they have said emphatically that they are doing their best to duplicate the RD-180 in every significant way.  I don't think they can come in much less or much above the RD-180's thrust level, nor can the Isp vary much, which means identical chamber size and pressure, bell dimensions, etc. Somewhere I did see something to the effect that every significant physical aspect of the RD-180 has been copied.

So in other words, you might be able to use an RD-180 in simulations.  Not sure whether that helps.  :)

I already have estimates of the performance of the AJ1E6, which I would use for the AR-1. I think that would be better than using the RD-180 as a reference.
Title: Re: SLS General Discussion Thread 2
Post by: TomH on 03/18/2016 02:47 PM
Changing the core to Kerolox would mean it is an entirely new rocket. The tanks have to be resized for the vastly different fuel/oxidizer volumetric ratio.

Though I first suggested it as fantasy, I think something much easier than this would be to replace RS-25 with J-2X, strengthen the core with strong-backs, and place it on top of BFR (S1 of MCT). What was the SLS core becomes the most powerful ever US atop the most powerful ever S1.

You get a stupendous initial boost from a reusable S1. Your SLS based US is air startable with an engine that has been fully developed and paid for. No longer needed are RS-25E, advanced boosters, or EUS. The SLS core could likely handle the remainder of ΔV to Earth orbit, TLI, LOI, and finish as a crasher stage for a robust Lunar lander.

I know it won't fit in the VAB, but it would mean NASA could simply lease S1 service from SpaceX, eliminate development of the three components listed above, begin developing other needed systems, and perhaps focus primarily on Luna while SpaceX focuses primarily on Mars.

Some have stated it would be better to build a Metholox US whose diameter matches the S1. The thing is, SpaceX is not planning that, but the BFS instead. This would be a way to leverage what is already in design by both entities. NASA is building the SLS core, but can't afford to do much else at the present time. SpaceX is in the middle of designing Raptor and MCT. Under this scheme, NASA would simple lease S1 launch service on BFR that is headed toward development. NASA could do relatively modest changes to SLS, forget advanced boosters, RS-25E, and EUS, and turn its attention to a lander. Mars is explored by SpaceX with some help from NASA and Luna is explored by NASA with some help from SpaceX.

Steven, if you have any interest in running calculations on this monster, I would be greatly interested in the results.

Title: Re: SLS General Discussion Thread 2
Post by: Zed_Noir on 03/18/2016 03:29 PM
...
Though I first suggested it as fantasy, I think something much easier than this would be to replace RS-25 with J-2X, strengthen the core with strong-backs, and place it on top of BFR (S1 of MCT). What was the SLS core becomes the most powerful ever US atop the most powerful ever S1.

You get a stupendous initial boost from a reusable S1. Your SLS based US is air startable with an engine that has been fully developed and paid for. No longer needed are RS-25E, advanced boosters, or EUS. The SLS core could likely handle the remainder of ΔV to Earth orbit, TLI, LOI, and finish as a crasher stage for a robust Lunar lander.

I know it won't fit in the VAB, but it would mean NASA could simply lease S1 service from SpaceX, eliminate development of the three components listed above, begin developing other needed systems, and perhaps focus primarily on Luna while SpaceX focuses primarily on Mars.

Some have stated it would be better to build a Metholox US whose diameter matches the S1. The thing is, SpaceX is not planning that, but the BFS instead. This would be a way to leverage what is already in design by both entities. NASA is building the SLS core, but can't afford to do much else at the present time. SpaceX is in the middle of designing Raptor and MCT. Under this scheme, NASA would simple lease S1 launch service on BFR that is headed toward development. NASA could do relatively modest changes to SLS, forget advanced boosters, RS-25E, and EUS, and turn its attention to a lander. Mars is explored by SpaceX with some help from NASA and Luna is explored by NASA with some help from SpaceX.
....

No need. Adopt the the rumored SX Raptor powered reusable upper stage as a lander. Just stick a HAB or cargo module on top of the upper stage.
Title: Re: SLS General Discussion Thread 2
Post by: TomH on 03/18/2016 03:35 PM
No need. Adopt the the rumored SX Raptor powered reusable upper stage as a lander. Just stick a HAB or cargo module on top of the upper stage.

That would require extra refueling launches. This approach also acknowledges the realpolitik of keeping pork flowing to particular states/districts and satisfying high ranking congresspersons.
Title: Re: SLS General Discussion Thread 2
Post by: Zed_Noir on 03/18/2016 03:50 PM
No need. Adopt the the rumored SX Raptor powered reusable upper stage as a lander. Just stick a HAB or cargo module on top of the upper stage.

That would require extra refueling launches. This approach also acknowledges the realpolitik of keeping pork flowing to particular states/districts and satisfying high ranking congresspersons.

Might be a bit of misunderstanding. The SX upper stage devised lander will go on top of your fantasy stack. So the lander's prop tanks should be fully filled for Lunar descend from LLO.
Title: Re: SLS General Discussion Thread 2
Post by: Lobo on 03/18/2016 04:46 PM
No need. Adopt the the rumored SX Raptor powered reusable upper stage as a lander. Just stick a HAB or cargo module on top of the upper stage.

That would require extra refueling launches. This approach also acknowledges the realpolitik of keeping pork flowing to particular states/districts and satisfying high ranking congresspersons.

Might be a bit of misunderstanding. The SX upper stage devised lander will go on top of your fantasy stack. So the lander's prop tanks should be fully filled for Lunar descend from LLO.

Tom,
I know this configuration has piqued your interest.  But I think cross pollinating these two would be much more difficult and expensive than either just sticking with SLS as is, or just switching to use MCT outright and buying launch services from SpaceX and cancelling SLS and Orion. 

(I think the latter will likely be what happens eventually anyway, but if it happened sooner, it could mean MCT is ready to fly sooner too.)

I just think that modifying the core to accommodate having a booster under pushing rather than above it pulling probably would be about as extensive as switching it to kerolox or whatever, by the time it's all said and done.  Especially with government and government contractors.

Title: Re: SLS General Discussion Thread 2
Post by: TomH on 03/18/2016 06:04 PM
I just think that modifying the core to accommodate having a booster under pushing rather than above it pulling probably would be about as extensive as switching it to kerolox or whatever, by the time it's all said and done.

My friend Lobo!

I remember the time when you proposed ganging three F9s with strongbacks and sticking a cluster on each side of SLS to act as the boosters. That's actually where I got the idea that I stated above of just strengthening the sides of the core with strongbacks only, no actual modifications of the walls. If clustering a trio of F9s on each side with strongbacks is possible, then it seems a strongback alone for structural reinforcement should also be possible.

I'm trying to think of the cheapest way to preserve certain congressmen's pork interests and yet still make it possible for NASA to do something with what otherwise is a boondoggle.

...just switching to use MCT outright and buying launch services from SpaceX and cancelling SLS and Orion....will likely be what happens eventually anyway, but if it happened sooner, it could mean MCT is ready to fly sooner too.)

This is what I expect will indeed happen. OTOH, those particular congresspersons have proven remarkably able to keep this pork line flowing. Though far from ideal, this preserves the pork currently in place, but perhaps could allow NASA to actually cook that pig and serve some food.
Title: Re: SLS General Discussion Thread 2
Post by: TomH on 03/18/2016 06:04 PM
Might be a bit of misunderstanding. The SX upper stage devised lander will go on top of your fantasy stack. So the lander's prop tanks should be fully filled for Lunar descend from LLO.


Ahhh, thanks!
Title: Re: SLS General Discussion Thread 2
Post by: Lobo on 03/18/2016 06:57 PM
I just think that modifying the core to accommodate having a booster under pushing rather than above it pulling probably would be about as extensive as switching it to kerolox or whatever, by the time it's all said and done.

My friend Lobo!

I remember the time when you proposed ganging three F9s with strongbacks and sticking a cluster on each side of SLS to act as the boosters. That's actually where I got the idea that I stated above of just strengthening the sides of the core with strongbacks only, no actual modifications of the walls. If clustering a trio of F9s on each side with strongbacks is possible, then it seems a strongback alone for structural reinforcement should also be possible.

I'm trying to think of the cheapest way to preserve certain congressmen's pork interests and yet still make it possible for NASA to do something with what otherwise is a boondoggle.

Ahhh...my youthful idealism back then.  ;-)

I probably could work to design strongbacks that way.  I guess when I proposed it for three F9 cores, it was before there really was much known about MCT, that that could be a rival HLV alternative.  And it was a reach for way to try to make an off the shelf liquid booster work with the type of SLS core they were developing.

Adapting it to fit on top a serial booster just seems like it's another reach beyond my reach.  :-)
But I am certainly flattered my reach could be inspiration.  Heh.

In addition to the load carrying strongbacks themselves...which probably wouldn't be too hard, there'd be adapting different air-lit engines to the MPS instead of RS-25's, then all the interfaces to stack the two.  (We've seen the issues with adapting the ICPS to SLS and then moving to the EUS.  So I think we'd see something like that play out getting an SLS core on there, but then later getting the PoR upper stage on there in the BFS.)

And then there's the height of this monster, and that LH2 will need to be brought to wherever it launches from (not to mention getting the SLS cores itself to wherever that is, if someplace other than LC-39.)

Not that it's not an interesting idea.  I just think by the time you are done you could be into it for more money than just sticking with SLS as is (to satisfy the pork considerations).
Like choosing to remodel a house.  If you aren't careful, you can be into it for most...or all...of the price of just going and buying a different house with the layout you preferred.
It could be easier to cancel SLS and have NASA pay SpaceX for an expendable Raptor powered upper stage first, while they are developing the actual BFS.  That upper stage can have all the same interfaces and sizes and such that BFS will, so that nothing new is needed for when BFS will sit on the booster.  It probably wouldn't have great BLEO capability for it's size, but since the stage would be expendable, it'd be a lot lighter than the BFS, so it might be adequate for NASA's purposes?  And more "conservative" than SpaceX's fully reusable plans with LEO refueling.  It becomes a really big F9R then.

It wouldn't be as politically popular as stocking with SLS because the contracts would run out with Boeing and ATK, but I think it may be more feasible than trying to put SLS on BFR. 

...just switching to use MCT outright and buying launch services from SpaceX and cancelling SLS and Orion....will likely be what happens eventually anyway, but if it happened sooner, it could mean MCT is ready to fly sooner too.)

This is what I expect will indeed happen. OTOH, those particular congresspersons have proven remarkably able to keep this pork line flowing. Though far from ideal, this preserves the pork currently in place, but perhaps could allow NASA to actually cook that pig and serve some food.

Yup....we never know...I think once a rival is flying, and with Elon promoting the heck out of it and offering attractive pricing...I think it'll be hard to deny any more like it is when it's just a paper rocket.
Title: Re: SLS General Discussion Thread 2
Post by: Steven Pietrobon on 03/19/2016 04:29 AM
Steven, if you have any interest in running calculations on this monster, I would be greatly interested in the results.

No interest at the moment. If it ever gets near to happening, I would do a simulation.
Title: Re: SLS General Discussion Thread 2
Post by: turbopumpfeedback2 on 03/28/2016 01:56 PM
What will be the steady state SLS flight rate?

SLS Block 2 will be 50% more massive than shuttle.

Shuttle launched on average about 4 times a year. So SLS should launch at least 2 to 3 times a year.

But I have heard on many occasions that SLS will be launched once every two years, or maybe but unlikely once a year.

This does not make sense to me. Why would the SLS launch rate be so low?

By this trend, next generation rocket system with the same mass as shuttle will be launched once a decade.



Title: Re: SLS General Discussion Thread 2
Post by: Jim on 03/28/2016 02:25 PM
What will be the steady state SLS flight rate?

SLS Block 2 will be 50% more massive than shuttle.

Shuttle launched on average about 4 times a year. So SLS should launch at least 2 to 3 times a year.

But I have heard on many occasions that SLS will be launched once every two years, or maybe but unlikely once a year.

This does not make sense to me. Why would the SLS launch rate be so low?


The SLS lacks payloads.

BTW, the shuttle flight rate was much higher in the 90's when it had payloads other than the ISS.
Title: Re: SLS General Discussion Thread 2
Post by: RonM on 03/28/2016 03:59 PM
What will be the steady state SLS flight rate?

SLS Block 2 will be 50% more massive than shuttle.

Shuttle launched on average about 4 times a year. So SLS should launch at least 2 to 3 times a year.

But I have heard on many occasions that SLS will be launched once every two years, or maybe but unlikely once a year.

This does not make sense to me. Why would the SLS launch rate be so low?


The SLS lacks payloads.

BTW, the shuttle flight rate was much higher in the 90's when it had payloads other than the ISS.

Yes, lack of payloads.

Congress is more than happy to pay for the development of SLS and Orion, but they don't seem willing to actually do anything with them other than a couple of test flights and maybe the Europa mission. Unless there is more money coming soon, and I doubt that, expect SLS to be cancelled by the mid twenties.

If the program was funded, NASA wants a minimum of one flight per year and SLS production could handle two flights per year.
Title: Re: SLS General Discussion Thread 2
Post by: ThereIWas3 on 03/28/2016 07:01 PM
I love this, from a ABC News item about the auditor's report on the SLS launch control software being behind schedule and over budget:

Quote
The software won't be ready until fall 2017, instead of this summer as planned, and important capabilities like automatic failure detection, are being deferred.

Yes, let's defer the safety features.  What could possibly go wrong?
Title: Re: SLS General Discussion Thread 2
Post by: A_M_Swallow on 03/29/2016 12:49 AM
What will be the steady state SLS flight rate?

SLS Block 2 will be 50% more massive than shuttle.

Shuttle launched on average about 4 times a year. So SLS should launch at least 2 to 3 times a year.

But I have heard on many occasions that SLS will be launched once every two years, or maybe but unlikely once a year.

This does not make sense to me. Why would the SLS launch rate be so low?

By this trend, next generation rocket system with the same mass as shuttle will be launched once a decade.


The other big difference is that the Space Shuttles were reusable vehicles where as the SLS are expendable vehicles. This may makes a big cost difference. The 6 Space Shuttles (including Enterprise) were repaired and used again. Each SLS will be used once and thrown away.
Title: Re: SLS General Discussion Thread 2
Post by: RocketGoBoom on 04/22/2016 04:13 PM
SLS and Orion are crowding out other areas of the NASA budget.

http://spacenews.com/senate-bill-cuts-other-nasa-programs-to-fund-sls-and-orion/

Quote
The bill provides $19.306 billion for NASA, an increase of more than $280 million from the administration’s request for fiscal year 2017 released in February. However, NASA’s exploration account, which includes SLS and Orion, is increased by nearly $1 billion from the request.

That increase includes about $840 million for the SLS, to $2.15 billion, and $180 million for Orion, to $1.3 billion. Exploration ground systems to support SLS and Orion also see a $55 million increase, although research and development activities are cut by more than $80 million.

The increase in exploration funding means that most other major NASA accounts suffered cuts from the administration’s request in the bill. Science, aeronautics, space technology and space operations were cut by a combined $660 million from the request. The aeronautics account suffered the largest cut on a percentage basis, seeing its request for $790 million cut by nearly 25 percent.

Within the $5.4 billion provided to science, $200 million less than the request, planetary science suffered the largest cut, of more than $160 million. The bill and report did not specify a funding level for a mission to Europa, although it did state it “remains supportive” of such a mission. The bulk of the support for a Europa mission, and the enhanced funding it has received in recent years, has come from the House.

Title: Re: SLS General Discussion Thread 2
Post by: RotoSequence on 04/22/2016 05:23 PM
Maybe Congress intends to fund the development of payloads as part of a piecemeal, step by step approach once they've finished building the launch vehicle? They do seem to be in an awfully big hurry to build this rocket and make sure it's absolutely ready and on schedule, even though it has basically nothing to do. It's vexing.  :o
Title: Re: SLS General Discussion Thread 2
Post by: Star One on 04/22/2016 07:09 PM
Maybe Congress intends to fund the development of payloads as part of a piecemeal, step by step approach once they've finished building the launch vehicle? They do seem to be in an awfully big hurry to build this rocket and make sure it's absolutely ready and on schedule, even though it has basically nothing to do. It's vexing.  :o

My thinking entirely. Has it escaped their notice that a launcher has to actually have something to launch in the first place.
Title: Re: SLS General Discussion Thread 2
Post by: Zed_Noir on 04/22/2016 07:52 PM
Maybe Congress intends to fund the development of payloads as part of a piecemeal, step by step approach once they've finished building the launch vehicle? They do seem to be in an awfully big hurry to build this rocket and make sure it's absolutely ready and on schedule, even though it has basically nothing to do. It's vexing.  :o

My thinking entirely. Has it escaped their notice that a launcher has to actually have something to launch in the first place.

Rationality and Congressional Critters? ::) The Critters is fine with the current setup, since the R&D dollars goes to certain Congressional districts. Getting something operational don't matter to them, otherwise several SLS payload should be bending metal already.
Title: Re: SLS General Discussion Thread 2
Post by: spacenut on 04/22/2016 08:50 PM
Well if the ATK/Orbital EELV rocket is developed using SLS solid components, strap on solids used for Vulcan, this should cut some manufacturing costs for the SLS.  How much we don't know.  Keeping assembly line work going is better than starting and stopping constantly. 

I think the original Ares I  & V concepts were fine using off the shelf parts.  All the money spent on 5 segment booster development, J2X development, etc went nowhere and built nothing.  All that money could have been spent developing the SSME as a air start engine, the only real development needed.  Then the existing 4 segment boosters would have been fine.  It would have been a lot cheaper.  Then after their development and getting into service, develop the composite boosters for improved performance.  It has been what 10-12 years and still no big rocket?  The EELV and reusable markets have made great strides in the same length of time.  Still water over the dam. 

When is SLS supposed to fly?  By the time it does Vulcan, Falcon Heavy, maybe even a metholox upper stage for Falcon Heavy, and a new EELV solid, and maybe even BO's New Sheppard reusable vehicle could be flying, all combined with in orbit refueling and evolved SEP propulsion would make SLS obsolete as far as overall costs to operate. 
Title: Re: SLS General Discussion Thread 2
Post by: edkyle99 on 04/27/2016 09:41 PM
Who knows if it will be built, but the video is awesome.
"If"?  It already is being built.

 - Ed Kyle

A bill is not paid until the cheque has cleared.

Block 0 SLS is in a race with Falcon Heavy and Vulcan Heavy. Definitely an "If" until Block 1A with its very heavy payload flies.
They are building Block 1 right now.  (Block 0 was an undeveloped concept.)  It will lift about 2.5 times more mass to escape velocity than an all-expendable Falcon Heavy and probably 6 times more than an all-recoverable Falcon Heavy. 

Block 1B is the next SLS, with the EUS upper stage that has been designed.  NASA has already ordered engines for that new upper stage and it looks like Block 1B will take over after only one or two Block 1 flights.  Block 1B is probably going to be able to boost 4 times more to escape than an all-expendable Falcon Heavy and 10 times more than an all-recoverable Heavy.

Vulcan Heavy is a concept that is not currently planned to be developed.  Vulcan-ACES will be powerful enough to do the EELV Heavy missions currently done by Delta 4 Heavy, but ACES is a few years down the road.  It will roughly match Falcon Heavy performance beyond LEO.

 - Ed Kyle 
Title: Re: SLS General Discussion Thread 2
Post by: Johnnyhinbos on 04/28/2016 01:56 AM
The six year old in me wonders if I can lick the giant beaters...

I've been in that room. I think if you tried you'd see a lot of folks hitting the floor real quick! (Kidding - all mixing operations are controlled remotely from a bunker...)
Title: Re: SLS General Discussion Thread 2
Post by: TomH on 04/28/2016 04:16 PM
Block 1.....will lift about 2.5 times more mass to escape velocity than an all-expendable Falcon Heavy and probably 6 times more than an all-recoverable Falcon Heavy.

And the actually pertinent questions are:
On what timeline?
At what price per kg?
Why are you so conveniently leaving out MCT?

I was an SLS believer at one time too............But then I'm far more of a realist than I am a believer.
Title: Re: SLS General Discussion Thread 2
Post by: edkyle99 on 04/28/2016 05:01 PM
Block 1.....will lift about 2.5 times more mass to escape velocity than an all-expendable Falcon Heavy and probably 6 times more than an all-recoverable Falcon Heavy.

And the actually pertinent questions are:
On what timeline?
At what price per kg?
Why are you so conveniently leaving out MCT?

I was an SLS believer at one time too............But then I'm far more of a realist than I am a believer.
NASA is working to a constrained budget on SLS and Orion, so whatever that is determines the "price".  The schedule is published.  Orion is the time constraint, not SLS.  MCT is a concept. SLS is being built, with quite a bit of flight hardware already complete.

Ed Kyle
Title: Re: SLS General Discussion Thread 2
Post by: CNYMike on 04/28/2016 05:49 PM
Who knows if it will be built, but the video is awesome.
"If"?  It already is being built.

 - Ed Kyle

Let me rephrase: the next administration could cancel it, then it's anybody's guess what comes next.  Trump is the wild card; who knows what he'll do?  Ten seconds of pandering to MSFC people isn't enough. 

Yes, it is being built.  Yes, it can fly.  Then again, NASA could be terminated and US space privatized completely.  We won't know until next year. 

FYI, I don't want the current manned programs canceled because we'd go through the same kind of mess that got us here in the first place.  But you can't count on whoever takes the white house to make that much sense.  And I'm not ruling Trump out until the first Wednesday in November. 

Hope that clears things up.
Title: Re: SLS General Discussion Thread 2
Post by: Coastal Ron on 04/28/2016 08:59 PM
SLS is being built, with quite a bit of flight hardware already complete.

The question has never really been "Can we build an HLV?", and so far Congress has been willing to appropriate the funds to develop such a system and get it ready for flying payloads that require it's unique capabilities.

The question has always been whether a government-owned HLV is needed or required at this point in history.  And so far the answer to that is not a resounding "Yes", but just a dribble of interest and money from Congress as a whole.

Unfortunately a dribble of support won't support the need to launch the SLS at the minimum safe flight cadence of no-less-than every 12 months, so there is a point coming very soon where having a government-owned transportation system but not having enough demand for it's unique capabilities must be reconciled...
Title: Re: SLS General Discussion Thread 2
Post by: Ben the Space Brit on 04/29/2016 08:57 AM
I think that the posters above are correct to emphasise that the question is 'should', not 'could'. Don't get me wrong, I'm a BFR fan-boy. I love these huge creatures. However, there is no point building The Rocket That Ate NASA if it never serves any significant purpose in the space program. I'd feel a lot more confident about SLS and its future if the following criteria were met:

1) Flight rate > 2/year;

2) Waiting list of payloads or fully-described, funded and in development missions that require its unique capabilities;

3) Any payload at all (i.e. human-ready Orion) that is expected to fly in < 5 years.

Right now, EM-1 is giving me uncomfortable Ares-I-X flashbacks.

You see... SpaceX are talking about a program of Red Dragon missions, mostly intended to gather data on and then prove all-propulsive Martian landings... starting NET 2018. When the first Dragon has pads down and is relaying data back from the Martian surface, things are going to get a lot more interesting on the Space, Science and Competitiveness Subcommittee, especially if the Gentleman from Texas is nursing a bruised ego and wants to prove himself again.
Title: Re: SLS General Discussion Thread 2
Post by: A_M_Swallow on 04/29/2016 04:45 PM
NASA could give a grant to a university professor to write a study showing how SLS could be used to build a lunar village. It does not matter if the SLS takes the habitats to lunar orbit or delivers say the rovers to a SEP tug waiting in LEO.

Providing the self funding holds out ULA and Masten should have the ability to land payloads of 5-10 tonnes on the Moon within 5 years. See Lunar_CATALYST. In about 15 years they plan to land 25 tonne payloads.
Title: Re: SLS General Discussion Thread 2
Post by: ncb1397 on 04/29/2016 05:14 PM
SLS is being built, with quite a bit of flight hardware already complete.

The question has never really been "Can we build an HLV?", and so far Congress has been willing to appropriate the funds to develop such a system and get it ready for flying payloads that require it's unique capabilities.

The question has always been whether a government-owned HLV is needed or required at this point in history.  And so far the answer to that is not a resounding "Yes", but just a dribble of interest and money from Congress as a whole.

Unfortunately a dribble of support won't support the need to launch the SLS at the minimum safe flight cadence of no-less-than every 12 months, so there is a point coming very soon where having a government-owned transportation system but not having enough demand for it's unique capabilities must be reconciled...

Is it really 12 months? why not 13 months or 11 months? Seems like a nice round number that happens to coincidentally coincide with the earth's orbit around the sun. If we are going to use calendars as arbitrary technical limitations, why not the Mars year - 687 days? I would like to point out that Apollo Soyuz test project was launched on a Saturn 1B 16 months after the previous Saturn 1B...and didn't explode.
Title: Re: SLS General Discussion Thread 2
Post by: Coastal Ron on 04/29/2016 05:47 PM
Is it really 12 months? why not 13 months or 11 months? Seems like a nice round number that happens to coincidentally coincide with the earth's orbit around the sun.

When there are a lot of unknowns, you have to try to make assumptions.  From an NSF article (https://www.nasaspaceflight.com/2014/02/sls-launch-rate-repetitive-cadence-gerstenmaier/):

"Although payloads are yet to be announced, Mr. Gerstenmaier confirmed the flight rate has to be once a year as a minimum requirement, in response to a question from Bejmuk – who had assumed SLS would only launch once every two or three years.

Mr. Gerstenmaier noted that “repetitive cadence is necessary” as the reason SLS will launch every year.
"

However it would be a whole host of reasons that they have used to distill down to an assumption of once per year, meaning any one of those assumptions could change - either for better or worse.  But you wouldn't know if it was for the worst unless you experienced a failure of some sort, which is a condition that NASA would rather not have.

Quote
I would like to point out that Apollo Soyuz test project was launched on a Saturn 1B 16 months after the previous Saturn 1B...and didn't explode.

And no doubt it could be that NASA could launch the SLS every 5 years and it would not explode.  But the cost of that one flight every 5 years would likely be enormous, for many reasons.

So it really does come down to cost - what is the overall cost associated with running a unique transportation system?  And what would be the cost to not have it?

Those are the questions that have not fully been asked and answered, but will have to be soon since the SLS manifest is virtually empty prior to it becoming operational...
Title: Re: SLS General Discussion Thread 2
Post by: notsorandom on 04/29/2016 06:34 PM
SLS is being built, with quite a bit of flight hardware already complete.

The question has never really been "Can we build an HLV?", and so far Congress has been willing to appropriate the funds to develop such a system and get it ready for flying payloads that require it's unique capabilities.

The question has always been whether a government-owned HLV is needed or required at this point in history.  And so far the answer to that is not a resounding "Yes", but just a dribble of interest and money from Congress as a whole.

Unfortunately a dribble of support won't support the need to launch the SLS at the minimum safe flight cadence of no-less-than every 12 months, so there is a point coming very soon where having a government-owned transportation system but not having enough demand for it's unique capabilities must be reconciled...

Is it really 12 months? why not 13 months or 11 months? Seems like a nice round number that happens to coincidentally coincide with the earth's orbit around the sun. If we are going to use calendars as arbitrary technical limitations, why not the Mars year - 687 days? I would like to point out that Apollo Soyuz test project was launched on a Saturn 1B 16 months after the previous Saturn 1B...and didn't explode.
The gap between Apollo 7 and Skylab 2 was even greater, 4 years 7 months and 14 days. Similarly the Delta II has some pretty big gaps in its recent launch history. The gap between Delta flight 357 and 367 is 2 years 8 months and 4 days. There is an almost 2 year gap between the last Delta II flight and the next one.

I can understand the desire to keep a regular launch cadence so the program's personnel have regular practice. However at least looking at these two rockets the gaps do not appear to present significant reliability issues. The professionals who work in this industry appear to be capable of reliably launching at any cadence. Accordingly I don't think the issue of launch cadence as it relates to reliability should be a factor the decision to continue or cancel the program. There are many pros and cons to the SLS program that are way more important than this hypothetical concern.
Title: Re: SLS General Discussion Thread 2
Post by: spacenut on 04/29/2016 07:35 PM
Where do you get SLS getting 2.5 times the LEO payload vs FH?  FH expendable, like SLS will be, is supposed to get 53 tons to LEO.  I thought SLS is or was to be between 95-105 tons to LEO in current configuration.  Spun wound composite boosters might get it to 115-120, but from what I understand, not 130.  For greater than 130 tons, wouldn't they have to add a 5th engine on the core and a larger upper stage say with J2x?  Now that Falcon has full thrust in their rocket, this will change the boosters LEO ability.  The Raptor upper stage engine is supposed to be developed in the next 18-24 months.  This may greatly increase FH's payload.  SLS is certainly not 2.5 times the proposed FH. 

Someone several years ago suggested the 40-60 ton payload range, using EELV's in heavy versions, in space docking, assembly, and refueling, would be all we needed have a viable moon or Mars program.  Also, with several vendors, no real downtime if one of the competitors had a failure.  No need for billions spent on SLS or $/kg cost. 

We seem to have vendors who leach off the government with constant delays and cost overruns.   
Title: Re: SLS General Discussion Thread 2
Post by: Endeavour_01 on 04/29/2016 07:54 PM
Where do you get SLS getting 2.5 times the LEO payload vs FH? 

Mr. Kyle was referring to escape velocity payload, not payload to LEO.

Edited to add:

Right now, EM-1 is giving me uncomfortable Ares-I-X flashbacks.

I am feeling some of that too but there are several differences between EM-1 and Ares I-X

1. EM-1 is a flight of a completely operational rocket. The core stage, boosters, and upper stage are all ready to go, as well as the LAS. Ares I-X had only the first stage operational, the upper stage and LAS were dummies.

2. EM-1 has a payload/mission. EM-1 will launch an unmanned Orion around the moon. Ares I-X had a dummy Orion that never made it to LEO.
Title: Re: SLS General Discussion Thread 2
Post by: TomH on 04/29/2016 08:45 PM
Where do you get SLS getting 2.5 times the LEO payload vs FH? 

Mr. Kyle was referring to escape velocity payload, not payload to LEO.

And Spacenut clearly mentioned:

The Raptor upper stage engine is supposed to be developed in the next 18-24 months

I surely imagine the Raptor US will fly on a FH long before EUS flies on an SLS Block IB. With FH now based on Falcon 9 v1.1FT, if cross feed were employed on a fully disposable FH with Raptor US, I highly doubt Block IB would get 2.5 x the payload to GTO or escape. And if you think of Block I (with iCPS) coming online about the same time as such a FH, the comparison is much closer...................until you look at the dollar signs attached to each.

I think MCT (at least the BFR booster) may fly before SLS Block IB ever does. In fact, I think a single Block I will fly. I now believe Blocks IB and IIB will never see the sky.

Jim used to predict that SLS would not succeed. He also was skeptical about SpaceX' Mars ambitions. I now believe he was right about the first one, not because of the reasons he enumerated, but rather because he underestimated the second one. Though it might have eventually fallen of its own problems, I think Super-FH and MCT will hasten the demise of SLS by years.
Title: Re: SLS General Discussion Thread 2
Post by: Coastal Ron on 04/29/2016 08:49 PM
The gap between Apollo 7 and Skylab 2 was even greater, 4 years 7 months and 14 days. Similarly the Delta II has some pretty big gaps in its recent launch history. The gap between Delta flight 357 and 367 is 2 years 8 months and 4 days. There is an almost 2 year gap between the last Delta II flight and the next one.

Apollo had already proven out their launch operations, and so mothballing them for a few years was OK to do, and back then salaries for their ground crew would probably not have been much of a budgetary problem.

Plus you can't look at the vehicle launch rate per se, since it is all facets of the rocket - production, launch operations, etc.  So for Delta II ULA was using the same factory personnel that were already trained, the same manufacturing support systems, the same launch ops personnel, etc.

For the SLS it's a combination of running the SLS at the very slow production rate of one per year, and only launching once per year.  Only doing something in the factory, or only doing something on the launch pad once per year does not promote good learning and retention.  And the currently forecasted launch rate means the SLS won't exit the "learning curve" for something like a decade.

Quote
Accordingly I don't think the issue of launch cadence as it relates to reliability should be a factor the decision to continue or cancel the program.

It is a significant factor that needs to be part of the decision, since it automatically removes any suggestion that the SLS could fly less often than once per year safely.  That pretty much mandates that unless Congress funds enough payloads and missions to fill up a yearly flight manifest that NASA won't feel the transportation is safe enough to use.  You have to draw the line somewhere to avoid "safety creep".

Quote
There are many pros and cons to the SLS program that are way more important than this hypothetical concern.

None that seem to include the phrase "We have more than enough SLS-only payloads funded and on track for launch to keep the SLS busy flying at least once per year for many years to come".  Which is main reason there is anything to debate about the SLS in the first place...
Title: Re: SLS General Discussion Thread 2
Post by: Endeavour_01 on 04/29/2016 08:59 PM
And Spacenut clearly mentioned:

The Raptor upper stage engine is supposed to be developed in the next 18-24 months

I surely imagine the Raptor US will fly on a FH long before EUS flies on an SLS Block IB. With FH now based on Falcon 9 v1.1FT, if cross feed were employed on a fully disposable FH with Raptor US, I highly doubt Block IB would get 2.5 x the payload to GTO or escape.


Ed was using the numbers we have currently for both SLS Block I/IB and Falcon Heavy. There are still many questions and unknowns on what the Raptor upper stage will actually be used for or what size engine it will be (mini or full scale) let alone payload performance numbers. I think he was justified in using the numbers we currently have vs. hypotheticals with plenty of unknowns.

Quote
I think MCT (at least the BFR booster) may fly before SLS Block IB ever does. In fact, I think a single Block I will fly. I now believe Blocks IB and IIB will never see the sky.

We will see. Given how much trouble and hard work SpaceX has had to do to get Falcon Heavy off the ground I doubt BFR will be flying until at least 2025.
Title: Re: SLS General Discussion Thread 2
Post by: TomH on 04/29/2016 11:14 PM
Given how much trouble and hard work SpaceX has had to do to get Falcon Heavy off the ground I doubt BFR will be flying until at least 2025.

You're working off of incorrect presuppositions. SpaceX has been smart enough to finish their refinements of F9 before proceeding to FH. Had they gone ahead with FH, then decided to refine F9, and then FH, they would be like the F-35 program: building production models prior to finishing with the test models. That's not working so well. Putting FH on hold while refining F9, mastering RTLS and at sea landing, then proceeding with FH has been a strategically shrewd, intentional, and practical move. It brings a much more robust as well as cost effective LV. There has been nothing troublesome or problematic about it.
Title: Re: SLS General Discussion Thread 2
Post by: spacenut on 04/29/2016 11:47 PM
Someone figured several years ago, that if they stayed with the 4 seg solids and 5 SSME's and a good upper stage, they could have flown 4-5 times a year for $1 billion.  Now one time for $1 billion.  To me it is sad. 

You are right about SpaceX.  They got Falcon 9 going by launching satellites from paying customers, Then upgraded the engines, then stretched the first stage, then attempted landing, then went full thrust.  Now a Raptor based upper stage for more capacity. 

IF again big IF, we had gone ahead with the 4 segment boosters and 3 SSME's we could have had the "Direct" booster already and be actually doing something in space.  Then we could have upgraded the boosters to either 5 segments or to the composite boosters, then added one or two more engines, stretched the core, and added J2X upper stage.  This could have been done over time.  Seems like they have over-engineered the SLS with all the changes.  Instead of getting started a few years ago, they had to wait for the new boosters, wait for the expendable SSME, develop the J2X and then cancel it.  Even Orion capsule seems to have taken forever to develop.  I don't know, it just seems like a huge waste of money instead of using what we already had off the shelf, then make upgrades. 

This is not the first time the Federal government has wasted money.  Just like the F-35, trying to make it a jack of all trades, but a master of none.  Seems like everything the Senate and House get involved in something, it becomes very expensive and seems to create more problems than it solves, especially when it is technical. 
Title: Re: SLS General Discussion Thread 2
Post by: Endeavour_01 on 04/30/2016 01:37 AM

You're working off of incorrect presuppositions. SpaceX has been smart enough to finish their refinements of F9 before proceeding to FH. .....Putting FH on hold while refining F9, mastering RTLS and at sea landing, then proceeding with FH has been a strategically shrewd, intentional, and practical move. There has been nothing troublesome or problematic about it.

I am not saying what they did was wrong. I think they did a great job and their iterative technique has worked wonderfully. What I am saying is that bigger projects have more issues and take more effort. Elon himself has said that Falcon Heavy was a much trickier proposition. I am sure if you asked any SpaceX engineer they would tell you that development of FH wasn't a breeze and they ran into troubles and problems that they fixed in the end. That is the case with any rocket development program.

BFR/BFS will be an order of magnitude more difficult. I am not saying they can't do it, just that it is not going to come out as soon as some people believe. It may be even longer if they plan to develop BFS alongside it.

SLS will have more than one flight as long as it isn't canned in the next admin. Even when BFR is flying SLS would still have a couple more flights given that it is crew rated (assuming BFS isn't ready yet).
Title: Re: SLS General Discussion Thread 2
Post by: oldAtlas_Eguy on 04/30/2016 02:52 AM
I doubt SLS/Orion 2017 appropriations will be threatened by this current news event. But add a successful test flight of FH, its publication of capabilities and prices and the 2018 appropriations may be in severe jeopardy. Also add to that a new administration a new congress makeup and it could be in really serious trouble. That's even if the media doesn't label it the "Rocket to Nowhere".  If that happens the congressmen will be ducking for cover and all political support for SLS/Orion will evaporate and funding for it would never even make it out of committee.

Hopefully some very useful payload projects that congress has started to fund, DSH for one, won't get axed with it. DSH does not care who launches it. It still has the same usefulness and the directions that NASA is going with the program is more in the direction taken with CRS and CC by looking for a development partner vs doing it all themselves. But the program is still just in its definition phase and not in its detailed design phase.

There are also other programs, the dual vehicle planetary probe launch being explored for launch using SLS, hopefully will not get damaged by a cancellation of SLS as well. When a LV that is being planned on by payloads disappears then addition funds are required to manifest to another LV if one is available at all!!!!

I look at the SLS/Orion program and see a train-wreck for NASA coming that is not avoidable. It is just a matter of when not if and how many other programs will be harmed when the wreck occurs.
Title: Re: SLS General Discussion Thread 2
Post by: rayleighscatter on 04/30/2016 03:06 AM
There is a space policy forum, but this isn't it.
Title: Re: SLS General Discussion Thread 2
Post by: Mark S on 04/30/2016 05:20 AM
.... Ares I-X had only the first stage operational, the upper stage and LAS were dummies.

No, it was worse than that. The Ares-1X first stage was not operational either. It was a standard four-segment Shuttle SRB with a dummy fifth segment bolted on top to make it look like a 5-segment RSRMV. The fifth segment was weighted down with ballast to simulate the mass of a real fifth segment. Which of course made the booster so heavy that the steel motor casing bent when it parachuted into the ocean.

Cheers!
Title: Re: SLS General Discussion Thread 2
Post by: Oli on 04/30/2016 01:42 PM
.... Ares I-X had only the first stage operational, the upper stage and LAS were dummies.

No, it was worse than that. The Ares-1X first stage was not operational either. It was a standard four-segment Shuttle SRB with a dummy fifth segment bolted on top to make it look like a 5-segment RSRMV. The fifth segment was weighted down with ballast to simulate the mass of a real fifth segment. Which of course made the booster so heavy that the steel motor casing bent when it parachuted into the ocean.

Cheers!

 ;D
Title: Re: SLS General Discussion Thread 2
Post by: woods170 on 04/30/2016 03:55 PM
.... Ares I-X had only the first stage operational, the upper stage and LAS were dummies.

No, it was worse than that. The Ares-1X first stage was not operational either. It was a standard four-segment Shuttle SRB with a dummy fifth segment bolted on top to make it look like a 5-segment RSRMV. The fifth segment was weighted down with ballast to simulate the mass of a real fifth segment. Which of course made the booster so heavy that the steel motor casing bent when it parachuted into the ocean.

Cheers!

Minor nit: what also contributed to the bent casing was the fact that two of the three main parachutes failed before splash-down. The first one failed outright (ripped apart) upon deployment. The second one deployed more-or-less normal but partially ripped apart a few seconds later. The end result was that the Ares I-X booster impacted the water with a higher velocity than anticipated.
Title: Re: SLS General Discussion Thread 2
Post by: Coastal Ron on 05/02/2016 03:29 AM
Someone figured several years ago, that if they stayed with the 4 seg solids and 5 SSME's and a good upper stage, they could have flown 4-5 times a year for $1 billion.

Whoever said that was clearly not rooted in reality.

Based on actual contracts for the Shuttle program when it was still in volume production, a flight set of SRB's (not including the SRM components) cost $68M.  For the External Tank (ET), which is smaller and less complex than the SLS 1st stage, it cost $173M each.  That's a total of $241M just for those two elements.

The SLS is far larger and more complex for the expendable hardware than the Shuttle was, plus the maximum capable production rate at this point in time is less than two per year, which doesn't really provide for cost reductions based on volume production at suppliers.  No one outside of NASA knows what the actual SLS cost will be, but I'd say it will be significant.

Quote
Now one time for $1 billion.  To me it is sad. 

Cost can only be evaluated when compared to the value one gets in return, and what the alternatives are in comparison.  There are many things U.S. Taxpayers pay more than $1B for and we feel it's worthwhile.  Will the SLS fall in that category?  Time will tell...
Title: Re: SLS General Discussion Thread 2
Post by: chrisking0997 on 05/02/2016 04:28 PM
maybe Im confused on the whole payload funding thing, but what SLS payloads has NASA proposed that Congress has not funded? 
Title: Re: SLS General Discussion Thread 2
Post by: oldAtlas_Eguy on 05/02/2016 05:41 PM
maybe Im confused on the whole payload funding thing, but what SLS payloads has NASA proposed that Congress has not funded?
For info on SLS payloads (manifest plans) or lack thereof see this thread: http://forum.nasaspaceflight.com/index.php?topic=39300.0 (http://forum.nasaspaceflight.com/index.php?topic=39300.0)

Currently there is Orion and DSH (DSH only recently in FY2016 started receiving any funding). With Europa investigating SLS suitability. It is both a problem of NASA putting forth more candidates and congress funding them. NASA doesn't want to put a new program in front of congress if they know it has almost no chance of getting funded. They wait for funding chance to increase before trying to get it funded. Look at what has happened to ARM.
Title: Re: SLS General Discussion Thread 2
Post by: spacenut on 05/02/2016 06:27 PM
I think BFR would be easier than Falcon Heavy, or heavy of any rocket.  It is a single core rocket, more or less only a sized up Falcon 9 with different engines.  Engines are the hardest to develop it seems.  SLS could have been a 9 engine RD-180 with the 8m core without solids.  It could have lifted far more than SLS and there could have been a twin engine J2X upper or 3 engine upper.  That would have lifted what a Saturn V lifted.  Then add Atlas V strap on's for additional boost.  I think that would have been cheaper than the current SLS. 
Title: Re: SLS General Discussion Thread 2
Post by: Coastal Ron on 05/02/2016 06:44 PM
I think BFR would be easier than Falcon Heavy, or heavy of any rocket.

Much as I love discussing alternatives, for this specific thread it doesn't matter that there may or may not be alternatives to using the SLS, it only matters whether Congress will fund the continuous use of the SLS via funding payloads and programs that can only use the unique services of the SLS.

And that is because the SLS is a government-owned transportation system that has unique capabilities, so as long as Congress funds things for it to move to space it will have a use - regardless what the possible alternatives are.

Which is why it doesn't really matter how much money is being spent on the SLS, or whether it's "on schedule".  What will decide the fate of the SLS is whether it's really needed to fly no-less-than once per year, and that clock starts in 2022 when it's supposed to become operational.
Title: Re: SLS General Discussion Thread 2
Post by: ncb1397 on 05/02/2016 07:14 PM
maybe Im confused on the whole payload funding thing, but what SLS payloads has NASA proposed that Congress has not funded?
For info on SLS payloads (manifest plans) or lack thereof see this thread: http://forum.nasaspaceflight.com/index.php?topic=39300.0 (http://forum.nasaspaceflight.com/index.php?topic=39300.0)

Currently there is Orion and DSH (DSH only recently in FY2016 started receiving any funding). With Europa investigating SLS suitability. It is both a problem of NASA putting forth more candidates and congress funding them. NASA doesn't want to put a new program in front of congress if they know it has almost no chance of getting funded. They wait for funding chance to increase before trying to get it funded. Look at what has happened to ARM.

It is now law that the Europa mission will use SLS. That is about as firm of a payload as you can get. I don't even think that Orion and DSH are required legally to be launched on SLS and so those are comparatively less firm.
Title: Re: SLS General Discussion Thread 2
Post by: The Amazing Catstronaut on 05/02/2016 08:05 PM

It is now law that the Europa mission will use SLS. That is about as firm of a payload as you can get. I don't even think that Orion and DSH are required legally to be launched on SLS and so those are comparatively less firm.

Orion is a questionable spacecraft design. I don't see much use for it unless it has some dedicated BEO missions on SLS. The first should be used as an enabler for the latter if Congress wants to be smart about it and draw SLS out.
Title: Re: SLS General Discussion Thread 2
Post by: Robotbeat on 05/03/2016 01:03 AM
maybe Im confused on the whole payload funding thing, but what SLS payloads has NASA proposed that Congress has not funded?
For info on SLS payloads (manifest plans) or lack thereof see this thread: http://forum.nasaspaceflight.com/index.php?topic=39300.0 (http://forum.nasaspaceflight.com/index.php?topic=39300.0)

Currently there is Orion and DSH (DSH only recently in FY2016 started receiving any funding). With Europa investigating SLS suitability. It is both a problem of NASA putting forth more candidates and congress funding them. NASA doesn't want to put a new program in front of congress if they know it has almost no chance of getting funded. They wait for funding chance to increase before trying to get it funded. Look at what has happened to ARM.

It is now law that the Europa mission will use SLS. ...
Then you might want to explain that to the mission designers who still baseline an EELV...
Title: Re: SLS General Discussion Thread 2
Post by: TomH on 05/03/2016 02:48 AM
It is now law that the Europa mission will use SLS.

Can you cite the bill that requires that, please? I know there were a lot of people hyping it, but I just don't remember any legislation to that effect. If I missed that, I would like to read what it says. Thanks.
Title: Re: SLS General Discussion Thread 2
Post by: TrevorMonty on 05/03/2016 02:59 AM
For Orion missions will ESA be providing service module for free?. I assume that buys them one or two seats.

Title: Re: SLS General Discussion Thread 2
Post by: Thorny on 05/03/2016 03:35 AM
It is now law that the Europa mission will use SLS.

Can you cite the bill that requires that, please? I know there were a lot of people hyping it, but I just don't remember any legislation to that effect. If I missed that, I would like to read what it says. Thanks.

https://www.congress.gov/114/plaws/publ113/PLAW-114publ113.pdf

Public Law 114-113, December 18, 2015
Consolidated Appropriations Act 2016

"Provided further, That, of the amounts provided, $175,000,000 is for an orbiter with a lander to meet the science goals for the Jupiter Europa mission as outlined in the most recent planetary science decadal survey: Provided further, That the National Aeronautics and Space Administration shall use the Space Launch System as the launch vehicle for the Jupiter Europa mission, plan for a launch no later than 2022, and include in the fiscal year 2017 budget the 5-year funding profile necessary to achieve these goals."
Title: Re: SLS General Discussion Thread 2
Post by: Coastal Ron on 05/03/2016 07:39 PM
For Orion missions will ESA be providing service module for free?. I assume that buys them one or two seats.

ESA was contributing the Service Module as part of their contribution to the ISS.  I'm not sure if that includes guaranteed crew participation on a future mission, but my guess would be it does not.

Also ESA is only designing the Service Module, building a complete unit for flight, and providing NASA the parts for a second unit.  It will be up to NASA to finish the assembly of the second unit, and to build future units.
Title: Re: SLS General Discussion Thread 2
Post by: woods170 on 05/04/2016 10:40 AM
For Orion missions will ESA be providing service module for free?. I assume that buys them one or two seats.

ESA was contributing the Service Module as part of their contribution to the ISS.  I'm not sure if that includes guaranteed crew participation on a future mission, but my guess would be it does not.

Also ESA is only designing the Service Module, building a complete unit for flight, and providing NASA the parts for a second unit.  It will be up to NASA to finish the assembly of the second unit, and to build future units.
Future units will be ordered from ESA within the bounds of yet another barter agreement. That barter agreement has been in-work for some time now, but the uncertainty over anything beyond EM-2 is making it hard to reach a hard agreement.
Title: Re: SLS General Discussion Thread 2
Post by: oldAtlas_Eguy on 05/12/2016 04:32 PM
If I am correct, NASA was not to long ago (less than a year) saying that they had a 6 month schedule margin. But now they are saying they have a 2 month schedule margin. That would imply that historically critical path schedule has changed dramatically in the last year.

Having worked on managing critical path schedule analysis and tracking for a very complex and almost daily changing schedule on the Shuttle VAFB pad work back in the mid 80s using scheduling analysis software (at that time very advanced, and now very common). The software showed what tasks were at risk for schedule slips and what tasks were not critical. But the list of critical tasks and non-critical tasks changed weekly due to dependencies on tasks that snarled to a near stop (work site accidents, mostly on hardware damage not personnel injuries). These were not a normally estimate effect on schedule.

Such an event would be analogous to the vertical welding machine problems.

If they are eating 4 months of margin for every 12 months of work and there is 30 months to go that 2 months of margin may well disappear with a slip occurring pushing the launch date out 6 months or more into as late as Mid 2019. Unfortunately as you get closer to launch more items become critical path and less items can be ignored (from a schedule standpoint). Hopefully there is actually more margin built into the individual tasks and that margin is not being shown in the work to date of Sept. This would be done by reevaluating all the tasks and adjusting their schedule estimates since the analysis as reported a year ago. Basically the remaining tasks would be more accurately estimated than they were a year ago.

But knowing what I do about schedule management of such very complex highly interdependent tasks, the new info on schedule does not give me a warm a fuzzy feeling on them meeting the Nov 2018 launch date.
Title: Re: SLS General Discussion Thread 2
Post by: mike robel on 05/12/2016 04:59 PM
@OldAtlas_Eguy:  If they are eating 4 months of margin for every 12 months of work and there is 30 months to go that 2 months of margin may well disappear with a slip occurring pushing the launch date out 6 months or more into as late as Mid 2019.

I won't be surprised if it gets pushed back to 2020...

Title: Re: SLS General Discussion Thread 2
Post by: DaveS on 05/12/2016 05:03 PM
The 6 month margin in the schedule got eaten up by the problems they discovered in the new Vertical Weld Center at MAF. It took a number of months to rectify the VWC problems. So, it isn't a generic SLS flaw or anything that made a number of months disappear, it was a manufacturing hardware fault.
Title: Re: SLS General Discussion Thread 2
Post by: oldAtlas_Eguy on 05/12/2016 05:21 PM
The 6 month margin in the schedule got eaten up by the problems they discovered in the new Vertical Weld Center at MAF. It took a number of months to rectify the VWC problems. So, it isn't a generic SLS flaw or anything that made a number of months disappear, it was a manufacturing hardware fault.
The key here is that such events happen quite often in a complex long duration engineering project, hence my reference to my experience with the Shuttle VAFB pad build work. It does not take much to create a major slip from an unexpected event even on a non-critical path item. As I mentioned earlier what is on the critical path changes weekly if not daily. That 2 month schedule margin is for handling such events. Lets hope they do not have any other events as severe as the welding machine.
Title: Re: SLS General Discussion Thread 2
Post by: rayleighscatter on 05/12/2016 10:00 PM
If I am correct, NASA was not to long ago (less than a year) saying that they had a 6 month schedule margin. But now they are saying they have a 2 month schedule margin. That would imply that historically critical path schedule has changed dramatically in the last year.
I wouldn't read it being that's how much margin they have, but rather that's how much margin they are confident enough to exploit at this point.
Title: Re: SLS General Discussion Thread 2
Post by: Retired Downrange on 05/13/2016 03:43 AM
http://arstechnica.com/science/2016/05/senator-cuts-nasas-tech-budge/
Title: Re: SLS General Discussion Thread 2
Post by: edkyle99 on 05/13/2016 04:07 AM


http://arstechnica.com/science/2016/05/senator-cuts-nasas-tech-budge/

Ugh.  Why did you make me read that?

 - Ed Kyle
Title: Re: SLS General Discussion Thread 2
Post by: Proponent on 05/13/2016 04:29 AM
For Orion missions will ESA be providing service module for free?. I assume that buys them one or two seats.

ESA was contributing the Service Module as part of their contribution to the ISS.  I'm not sure if that includes guaranteed crew participation on a future mission, but my guess would be it does not.

Also ESA is only designing the Service Module, building a complete unit for flight, and providing NASA the parts for a second unit.  It will be up to NASA to finish the assembly of the second unit, and to build future units.

So, essentially what seems to be happening is that part of the ISS budget is being diverted to Orion, right?
Title: Re: SLS General Discussion Thread 2
Post by: Coastal Ron on 05/13/2016 04:50 AM
For Orion missions will ESA be providing service module for free?. I assume that buys them one or two seats.

ESA was contributing the Service Module as part of their contribution to the ISS.  I'm not sure if that includes guaranteed crew participation on a future mission, but my guess would be it does not.

Also ESA is only designing the Service Module, building a complete unit for flight, and providing NASA the parts for a second unit.  It will be up to NASA to finish the assembly of the second unit, and to build future units.

So, essentially what seems to be happening is that part of the ISS budget is being diverted to Orion, right?

That would appear to be the case, since ESA is doing Orion work to pay for their part of the ISS instead of doing things that contribute to scientific output on the ISS.
Title: Re: SLS General Discussion Thread 2
Post by: Robotbeat on 05/13/2016 04:52 AM
Sounds like a huge waste of money. NASA should've just built it themselves in the first place. Of course, we knew that from the beginning.

It's just a move designed to maintain political support for Orion.
Title: Re: SLS General Discussion Thread 2
Post by: The Amazing Catstronaut on 05/13/2016 09:06 AM
Sounds like a huge waste of money. NASA should've just built it themselves in the first place. Of course, we knew that from the beginning.

It's just a move designed to maintain political support for Orion.

How much cash is going to get misdirected on "maintenance"?

Oh well. #JourneyToMars.
Title: Re: SLS General Discussion Thread 2
Post by: The Amazing Catstronaut on 05/13/2016 09:09 AM
It's not much we didn't already know, although it's good to see it getting some mainstream publicity.

[TiredOldOpinions]SLS isn't intrinsically bad, it's just intrinsically purposeless. [/TiredOldOpinions]
Title: Re: SLS General Discussion Thread 2
Post by: MATTBLAK on 05/13/2016 09:38 AM
If they were doing manned Lunar Sortie missions in preparation for a small manned Outpost - it would have purpose! Two manned plus two cargo missions per year would give it a decent enough flight rate to justify the expense of the standing armies of production and infrastructure. Also; 'trickle' funding has resulted in a virtual three-step development: Block 1, Block 1B and Block II. I feel that if they were going to be throwing away all this massive hardware each time (we call that expendable, eh?) then they should be shooting for the best and most powerful version from the word GO. Lifting 130, 140 or even 150 tons to LEO per launch would go a long way to justifying such a large expendable. I also believe Mars is, sadly, an unfunded Powerpoint fantasy at this point :(

But if Mars truly did enter the budgetary and political realms of possibility; the SLS with a decent flight rate and coupled with wonderfully enabling and leveraging technologies like SEP, ISRU and Propellant Depots could give mankind the Solar System. Or... We could just wait until Elon and other Commercial Superheroes get round to getting to Mars more cheaply and in their own time. It wont happen overnight; but it will happen.

Leave Mars to Space X and their ilk - build an International Lunar Outpost at the Lunar South Pole. NASA (U.S.A.) provides the Heavy Lift with SLS Block II(ish) and the Orion 'Mothership' and perhaps an ESA/JAXA/Commercial consortium builds the Manned Lunar Lander that also has a close 'stablemate' for cargo; as Soyuz has the Progress.

But you could still do the Lunar Outpost with lesser launchers than SLS if SLS gets canned - Vulcan/ACES, Falcon Heavy, Ariane 6 and the H-IIB could all contribute with distributed launch salvos per launch windows. It can be done - smarter folk than me have written books and papers on this stuff, you know...
Title: Re: SLS General Discussion Thread 2
Post by: The Amazing Catstronaut on 05/13/2016 12:55 PM
If they were doing manned Lunar Sortie missions in preparation for a small manned Outpost - it would have purpose! Two manned plus two cargo missions per year would give it a decent enough flight rate to justify the expense of the standing armies of production and infrastructure. Also; 'trickle' funding has resulted in a virtual three-step development: Block 1, Block 1B and Block II. I feel that if they were going to be throwing away all this massive hardware each time (we call that expendable, eh?) then they should be shooting for the best and most powerful version from the word GO. Lifting 130, 140 or even 150 tons to LEO per launch would go a long way to justifying such a large expendable. I also believe Mars is, sadly, an unfunded Powerpoint fantasy at this point :(


Agreed, SLS is perfectly scaled for a lunar program and would be an enabler for a manned return to the moon. It's too expensive to go to Mars with expendables but you can go to the moon with expendables. Why not? It would justify SLS having a flight rate of value, without requiring so many launches that it should be bank breaking beyond what SLS already is.  SLS at least makes an Apollo-like program repeatable, certainly enables large payloads to cislunar and perhaps even a minor lunar surface outpost.

However, it's not going to be used for any of those things yet, which is eyewatering. I can see a shift to lunar for SLS happening eventually, but it's not going to happen in this tumultuous year.
Title: Re: SLS General Discussion Thread 2
Post by: Rocket Science on 05/13/2016 01:07 PM
I'm a baby boomer and I don't recall a non-tumultuous year since I was born... This is normal, they either get on with it or they don't... Just sayin' ;)
Title: Re: SLS General Discussion Thread 2
Post by: notsorandom on 05/13/2016 05:11 PM
If they were doing manned Lunar Sortie missions in preparation for a small manned Outpost - it would have purpose! Two manned plus two cargo missions per year would give it a decent enough flight rate to justify the expense of the standing armies of production and infrastructure. Also; 'trickle' funding has resulted in a virtual three-step development: Block 1, Block 1B and Block II. I feel that if they were going to be throwing away all this massive hardware each time (we call that expendable, eh?) then they should be shooting for the best and most powerful version from the word GO. Lifting 130, 140 or even 150 tons to LEO per launch would go a long way to justifying such a large expendable. I also believe Mars is, sadly, an unfunded Powerpoint fantasy at this point :(


Agreed, SLS is perfectly scaled for a lunar program and would be an enabler for a manned return to the moon. It's too expensive to go to Mars with expendables but you can go to the moon with expendables. Why not? It would justify SLS having a flight rate of value, without requiring so many launches that it should be bank breaking beyond what SLS already is.  SLS at least makes an Apollo-like program repeatable, certainly enables large payloads to cislunar and perhaps even a minor lunar surface outpost.

However, it's not going to be used for any of those things yet, which is eyewatering. I can see a shift to lunar for SLS happening eventually, but it's not going to happen in this tumultuous year.
Mars Vs Moon is a political decision and not one based on capabilities yet. We are on a Journey To Mars because that is what administration is saying. That could switch tomorrow to the Moon and NASA would be in a good position to accomplish that goal with the current roster of programs and capabilities. At this point along The Journey To Mars we haven't arrived at the point where the road to Mars splits from the road to the Moon. SLS, Orion, DSH, SEP are just as useful for a lunar program as a Mars program (if not more so). The down select to a destination can still be done a few years form now without too much trouble. Its only when things like surface habitats, and landers need to be developed that one place or another has to be chosen. In this context SLS's ambiguity of destination and mission is a feature not a defect.
Title: Re: SLS General Discussion Thread 2
Post by: The Amazing Catstronaut on 05/13/2016 05:39 PM
If they were doing manned Lunar Sortie missions in preparation for a small manned Outpost - it would have purpose! Two manned plus two cargo missions per year would give it a decent enough flight rate to justify the expense of the standing armies of production and infrastructure. Also; 'trickle' funding has resulted in a virtual three-step development: Block 1, Block 1B and Block II. I feel that if they were going to be throwing away all this massive hardware each time (we call that expendable, eh?) then they should be shooting for the best and most powerful version from the word GO. Lifting 130, 140 or even 150 tons to LEO per launch would go a long way to justifying such a large expendable. I also believe Mars is, sadly, an unfunded Powerpoint fantasy at this point :(


Agreed, SLS is perfectly scaled for a lunar program and would be an enabler for a manned return to the moon. It's too expensive to go to Mars with expendables but you can go to the moon with expendables. Why not? It would justify SLS having a flight rate of value, without requiring so many launches that it should be bank breaking beyond what SLS already is.  SLS at least makes an Apollo-like program repeatable, certainly enables large payloads to cislunar and perhaps even a minor lunar surface outpost.

However, it's not going to be used for any of those things yet, which is eyewatering. I can see a shift to lunar for SLS happening eventually, but it's not going to happen in this tumultuous year.
Mars Vs Moon is a political decision and not one based on capabilities yet. We are on a Journey To Mars because that is what administration is saying. That could switch tomorrow to the Moon and NASA would be in a good position to accomplish that goal with the current roster of programs and capabilities. At this point along The Journey To Mars we haven't arrived at the point where the road to Mars splits from the road to the Moon. SLS, Orion, DSH, SEP are just as useful for a lunar program as a Mars program (if not more so). The down select to a destination can still be done a few years form now without too much trouble. Its only when things like surface habitats, and landers need to be developed that one place or another has to be chosen. In this context SLS's ambiguity of destination and mission is a feature not a defect.

I agree with you, and I believe that it's where SLS will end up going if its not superseded by commercial competition within the first 5-10 years of life. I'm someone who is of the opinion that Mars and Lunar will happen roughly around the same timeframe as each other - but they'll be handled differently with different players (initially) going to each. The moon isn't needed to go to mars, but a lot of what you need to go to mars will help you establish sustained (and that's the key word here) operations around the moon. If SpaceX doesn't die or massively change its ideological bent, they will be going to Mars at some point. Good for them - SLS can go to the moon, L1, L2, near earth asteroids, you name it. SpaceX's mars plans are comparatively razor sharp. NASA's mars goals are redirectable, and that's pivotal. I'm fairly certain that NASA top brass are conscious of this hence the emphasis on habitats and enabling technologies. If SLS and Orion get off the ground, they should be used in the sphere that they're suited for.

As for distributed launch - I'd use distributed launch for most supplies to a lunar outpost/space station. Use SLS for launching major, monolithic elements (and use Orion for crew rotation since you've built it). Make the costs possible by using distributed launch for everything else. Everyone's happy - SLS gets a decent flight rate, it's not directly competing with commercial enterprise in the eyes of congress, commercial enterprise gets to make revenue, NASA doesn't have to deal with a mars mission using an expendable launch architecture, everyone gets to be winners.

For a real-world analogy, shuttle was used to launch a lot of ISS components and did some crew ops, but to make the project affordable soyuz and progress did a lot of the crew and cargo lifting. SLS is the shuttle of the modern era - let's use it in the manner in which shuttle had a commendable service history.
Title: Re: SLS General Discussion Thread 2
Post by: Pipcard on 05/14/2016 12:13 AM
If they were doing manned Lunar Sortie missions in preparation for a small manned Outpost - it would have purpose! Two manned plus two cargo missions per year would give it a decent enough flight rate to justify the expense of the standing armies of production and infrastructure.
Indeed, but remember when a lunar mission requiring multiple SLS launches was considered to be bad news (http://www.nasaspaceflight.com/2013/08/dual-sls-required-nasas-lunar-landing-option/)? (because each launch is so cost inefficient, and the turnaround takes six months - was that a technical or budgetary limitation?) And they claimed that there wasn't enough funding for a lander.

It is beyond ridiculous that lunar missions during Apollo could be launched with one launch, but a similar capable launch vehicle now requires two launches. Unbelievable.

Yes, I know that this is an architecture for landing 4 astronauts at the poles. But still...

Concur! That was exactly the same reaction I had when I saw that when I first read the presentation, and why it's the headline.

"But still" is not an excuse, it's twice the number of astronauts with twice the surface stay time as Thorny pointed out (http://forum.nasaspaceflight.com/index.php?topic=32638.msg1086719#msg1086719).
Title: Re: SLS General Discussion Thread 2
Post by: MATTBLAK on 05/14/2016 12:59 AM
The 4x crew architecture shown in that article would be spectacular and useful - but of course, expensive. The most powerful Block II SLS version envisaged could do a more basic lunar mission in one launch - similar to the Apollo J-series missions but better. Say, a crew of two to the surface for a whole week instead of three days as in Apollo, with a lander halfway in size between the Apollo LM and Constellation's 'Altair'.

If they could keep the missions to 1x SLS Block II launch per time, then costs would be kept down, but capabilities could rise over time, with or without extra SLS launches. One week Sortie missions could use a crew of three to start with with two going to the surface and one staying in lunar orbit, as in Apollo. But once Habitation modules had been established on the surface, the crew could grow to 4x Astronauts with the lander taking them all down at once and the Orion orbiting alone as originally envisaged. And as mentioned by someone else, Outpost cargo supply could be done commercially. Heh, I could even see a version of Dragon soft-landing a couple tons of cargo next to an Outpost. Though for a basic Outpost discussion/design, we could start another thread ;)
Title: Re: SLS General Discussion Thread 2
Post by: TomH on 05/14/2016 03:23 AM
If SpaceX doesn't die or massively change its ideological bent, they will be going to Mars at some point. Good for them - SLS can go to the moon, L1, L2, near earth asteroids, you name it. SpaceX's mars plans are comparatively razor sharp. NASA's mars goals are redirectable, and that's pivotal. I'm fairly certain that NASA top brass are conscious of this hence the emphasis on habitats and enabling technologies. If SLS and Orion get off the ground, they should be used in the sphere that they're suited for.

BFS will be flying long before any SLS-Orion missions set out toward another celestial body. BFS will be capable of Lunar landings. I would not at all be surprised by an early BFS demonstration landing on Luna. I think that after a BFS performs the highest number of missions to Mars that is deemed safe, or after it is replaced by a block upgrade, it may then be used to sell service for a couple of lunar missions to NASA, prior to permanent retirement. I have given up on SLS-Orion. They are never going to accomplish anything.
Title: Re: SLS General Discussion Thread 2
Post by: MATTBLAK on 05/14/2016 05:58 AM
You're putting a lot of faith into something that's not even close to flying! Still, I want you to be right far more than I don't...
Title: Re: SLS General Discussion Thread 2
Post by: TrevorMonty on 05/14/2016 03:41 PM
The 4x crew architecture shown in that article would be spectacular and useful - but of course, expensive. The most powerful Block II SLS version envisaged could do a more basic lunar mission in one launch - similar to the Apollo J-series missions but better. Say, a crew of two to the surface for a whole week instead of three days as in Apollo, with a lander halfway in size between the Apollo LM and Constellation's 'Altair'.

If they could keep the missions to 1x SLS Block II launch per time, then costs would be kept down, but capabilities could rise over time, with or without extra SLS launches. One week Sortie missions could use a crew of three to start with with two going to the surface and one staying in lunar orbit, as in Apollo. But once Habitation modules had been established on the surface, the crew could grow to 4x Astronauts with the lander taking them all down at once and the Orion orbiting alone as originally envisaged. And as mentioned by someone else, Outpost cargo supply could be done commercially. Heh, I could even see a version of Dragon soft-landing a couple tons of cargo next to an Outpost. Though for a basic Outpost discussion/design, we could start another thread ;)
Realistically plan on 1x1B launch plus additional commercial LVs eg FH, A6 and Vulcan,  per lunar mission. Crew go on SLS while commercial LVs deliver lander/landers and fuel to staging post. In case of large crew rovers, they maybe landed separate to crew, using commercial LVs.

SLS would only launch once commercial LVs have completed their work.
Title: Re: SLS General Discussion Thread 2
Post by: Endeavour_01 on 05/14/2016 04:40 PM
Realistically plan on 1x1B launch plus additional commercial LVs eg FH, A6 and Vulcan,  per lunar mission. Crew go on SLS while commercial LVs deliver lander/landers and fuel to staging post. In case of large crew rovers, they maybe landed separate to crew, using commercial LVs. SLS would only launch once commercial LVs have completed their work.

Personally I believe that is the architecture that should be adopted. SLS tag teaming with commercial LVs. SLS can be used to launch crew and super heavy payloads (like an L2 gateway station) while commercial vehicles handle cargo delivery. As you mentioned one of the benefits of this architecture is that SLS can be launched as needed instead of having the weight of all the payload and the timetable of the mission. Then as time goes on we can have a lunar version of what is happening soon in LEO with commercial crew.

I have given up on SLS-Orion. They are never going to accomplish anything.

Whenever I see the short sighted arguments back and forth for SLS to be cancelled or for SLS to do all the work I am reminded of what it took to get to this point. It has been 44 years since the last moon landing. In my own time on this planet I can remember the late '90s and early 2000s when NASA couldn't even discuss going beyond LEO in the foreseeable future. I remember the calls from some after Columbia for manned spaceflight to be abandoned altogether. We have come a long way since then. The fact that we will soon have a wealth of capability with SLS/FH for BEO missions is a blessing.

Instead of endless arguments over which is the more "perfect" system can we please use what we have to actually do something instead of just talking about it? No system is perfectly sustainable or perfectly made. Be grateful for what we have and don't try to destroy a BEO capability that is years in the making just because it doesn't match up with what you think should happen.

Rant over. Continue with your regularly scheduled discussion. ;D
Title: Re: SLS General Discussion Thread 2
Post by: oldAtlas_Eguy on 05/14/2016 07:34 PM
This makes me think of a quote:
“Do. Or do not. There is no try.” Yoda, The Empire Strikes Back


Unfortunately this rings a bit of truth about manned BEO with SLS/Orion being an attempt ("try") rather than a solid "Do". In comparison Apollo was a solid "Do".

The Manned BEO program whatever it uses needs to be a solid "Do" in the minds of all the stakeholders in the effort. The stakeholders being NASA, Congress, the Administration, contractors, and even the US public.

So all the controversy is an extension of the "try". I like you would like to see manned BEO a "Do" no matter who or how it is done. If SLS/Orion get's it done then good.

My rant over.

No back to SLS:
Do we have any new hardware delivery milestones (that moved or not moved) related to this latest public statements of SLS/Orion being "on Track?.
Title: Re: SLS General Discussion Thread 2
Post by: TomH on 05/14/2016 07:51 PM
I have given up on SLS-Orion. They are never going to accomplish anything.

Whenever I see the short sighted arguments back and forth for SLS to be cancelled or for SLS to do all the work I am reminded of what it took to get to this point. It has been 44 years since the last moon landing. In my own time on this planet I can remember the late '90s and early 2000s when NASA couldn't even discuss going beyond LEO in the foreseeable future. I remember the calls from some after Columbia for manned spaceflight to be abandoned altogether. We have come a long way since then. The fact that we will soon have a wealth of capability with SLS/FH for BEO missions is a blessing.

Instead of endless arguments over which is the more "perfect" system can we please use what we have to actually do something instead of just talking about it? No system is perfectly sustainable or perfectly made. Be grateful for what we have and don't try to destroy a BEO capability that is years in the making just because it doesn't match up with what you think should happen.

Rant over. Continue with your regularly scheduled discussion. ;D

1. It isn't short-sighted.
2. I didn't call for it to be cancelled. It will accomplish that on its own.
3. What it took to get to this point....this point is actually loss of ground.
4. In MY time on this planet, I remember seeing six manned lunar landings in a matter of months. YOUR time on this planet....well....I'm sad we regressed during that time.
5. Use what we have to do something? What we have isn't capable of doing anything. We had MORE capable architecture when I was a teenager almost 5 decades ago.
6. Be grateful for what we have??? Um...NO. Throwing good money after bad is foolish. It's time to let go of that albatross. (The thing is so expensive that there is no money for payloads...not for Mars, which is what they say the thing is for. Orion isn't Mars capable. There isn't even money for a lunar lander.) SpaceX' architecture is going to be more cost effective by between one and two orders of magnitude. It's time to get on the right ship.
7. You are right about that being a rant.
Title: Re: SLS General Discussion Thread 2
Post by: Endeavour_01 on 05/15/2016 12:19 AM

3. What it took to get to this point....this point is actually loss of ground.

How is that so? Sure we aren't landing people on the moon so it is a loss of ground from the lunar landings but I am referring to the time period after that. From the point where the lunar landings ceased (LEO flights only and no BEO capable rocket or spacecraft) to now the last few years have seen a tremendous amount of ground regained. We are actually building the systems that will allow for BEO missions (SLS, FH, Orion etc.). 20 years ago that was a pipe dream.

Quote
4. In MY time on this planet, I remember seeing six manned lunar landings in a matter of months.
YOUR
time on this planet....well....I'm sad we regressed during that time.5. Use what we have to do something? What we have isn't capable of doing anything. We had MORE capable architecture when I was a teenager almost 5 decades ago.

I understand your frustration. That said the fact that you saw the lunar landings and experienced the amount of time it has taken to even consider BEO missions again should show you that getting money spent on BEO mission capable systems (from both government and private sources) is progress.

Quote
6. Be grateful for what we have??? Um...NO. Throwing good money after bad is foolish. It's time to let go of that albatross. (The thing is so expensive that there is no money for payloads...not for Mars, which is what they say the thing is for. Orion isn't Mars capable. There isn't even money for a lunar lander.) SpaceX' architecture is going to be more cost effective by between one and two orders of magnitude. It's time to get on the right ship.

This is what I was trying to address in my post. There is no need to turn this into a "us vs. them" (SpaceX vs. NASA) fight. None of us has a crystal ball that enables us to see the future. It is very possible that SpaceX's architecture will outclass and replace SLS/Orion in the future. I am fine with that.

The point that needs to be made here is that SLS/Orion are not impeding that architecture. You might say, "Well if the SLS money was going to SpaceX...." but even if that was the case SpaceX would be subject to the same Congressional funding cycle whims that NASA is subject to. It is far better for SpaceX to develop their architecture under their direction and funding streams. That way there is dissimilar redundancy (if SLS/Orion fails we have a backup and vice versa) and SpaceX is free of any government meddling.

Also the fact is that SLS/Orion take up less room in the budget than the shuttle did (and I will note we built a massive space station while simultaneously flying the shuttle). Sure it is more expensive than we want but lets not treat it as the most expensive thing ever.

This "you are only a space fan if you love SpaceX and hate SLS/Orion" attitude (or the reverse) is getting quite tiring.
Title: Re: SLS General Discussion Thread 2
Post by: The Amazing Catstronaut on 05/15/2016 12:35 AM
Hold the horses. I believe SpaceX's BEO architecture is going to be the future, but that horse isn't old enough for the races yet.

The problem with SLS is not the LV - granted, the fundamental ethos behind it is dated. Yes, it will be approaching the point of being outmoded by the time it launches. Is it too expensive? Yes. Is it useless? No. Is the program salvageable? Yes.

With clear BEO targets and a respectable launch cadence SLS becomes an enabler and will start to pay back on its investment. Without those targets, at least SLS employed some people. It's only public money anyhow - it'll all end back in the pockets of the taxpayer at some point. The true loss is time and a lack of focus and missed intellectual capital if SLS falls flat. That's why it's crucial SLS works. That's why we should be invested in seeing SLS succeed.

You don't need to stand up for SpaceX. SpaceX is doing a real fine job of standing up for itself.
Title: Re: SLS General Discussion Thread 2
Post by: RyanC on 05/15/2016 01:59 AM
Don't worry, Long March 9 will do what SLS couldn't do; along with MCT.
Title: Re: SLS General Discussion Thread 2
Post by: su27k on 05/15/2016 07:04 AM
Instead of endless arguments over which is the more "perfect" system can we please use what we have to actually do something instead of just talking about it? No system is perfectly sustainable or perfectly made. Be grateful for what we have and don't try to destroy a BEO capability that is years in the making just because it doesn't match up with what you think should happen.

{rant}
This "use what we have to do something" attitude is the problem with post-2000 NASA plans. There's no long range planning, no technology development, since congress won't increase the budget, let's just use what legacy system we have (i.e. leftover Shuttle hardware)  to do something (repeat Apollo).

Let's say the next few Presidents want to redo Apollo, Orion and SLS block II won't be ready until 2024 at the earliest, add a new lander, you're looking at landing on the Moon in 2035 or so. Then what? You're still using the legacy system which has very limited growth potential, you're basically boxed in with no way out, so most likely it would be similar to the Shuttle where you repeat the same thing for another 30 years. Forgive me for not finding this inspirational.

This is never about SpaceX or "perfect" system, people used to obsess about DC-X/X-33 too, I bet you'll see SLS vs very/very/very big brother if Bezos announces a super heavy tomorrow. The reason people don't respect program of record "BEO" capability is because it's so depressing.
{/rant}
Title: Re: SLS General Discussion Thread 2
Post by: Dasun on 05/15/2016 02:00 PM
Good grief so much wretched hand wringing !

Flight metal is being bent, the SLS/Orion stack will fly BEO unmanned in late 2018 ( assuming a successful launch! ) and BFR will not even be past PDR and may never make it beyond Powerpoint . 

SLS is a heavy lift tool, it is up to future administrations to decide if and how it will be used.  But if it is used it can plug into many exploration architectures - both alone or in concert with commercial - as the first element of moving big stuff upstairs.

Be thankful that serious talk of BEO is happening now, it has been a long time coming for us true believers and might still die on the vine ...
Title: Re: SLS General Discussion Thread 2
Post by: TomH on 05/15/2016 05:59 PM
Good grief so much wretched hand wringing !

Flight metal is being bent, the SLS/Orion stack will fly BEO unmanned in late 2018 ( assuming a successful launch! ) and BFR will not even be past PDR and may never make it beyond Powerpoint . 

SLS is a heavy lift tool, it is up to future administrations to decide if and how it will be used.  But if it is used it can plug into many exploration architectures - both alone or in concert with commercial - as the first element of moving big stuff upstairs.

Be thankful that serious talk of BEO is happening now, it has been a long time coming for us true believers and might still die on the vine ...

So what if flight metal is being bent? What good is a rocket when there's nothing to put on top of it?

Your 2018 launch may well be the only launch SLS ever sees. As for BFR not making it beyond Powerpoint-no one believed SET (Space Exploration Technologies aka SpaceX) could build rockets as cheaply as they do and virtually everyone said returning a rocket from hypersonic speed and landing it on its tail was beyond impossible. SET has not only done that, in a matter of months they have done it in the middle of the ocean.......beginning the burn mere seconds before impact.......setting the thing perfectly in the center of a bullseye.

I am tired of living in the past. SLS is literally going nowhere. SET has proven their technological, logistical, and financial management prowess. SLS exists for one reason-to funnel pork. People who believe that SLS is the future are like admirals who clung to battleships after Pearl Harbor. Their future was in carriers. I don't have that many years left on this planet and I want to see my species on the Red Planet in my lifetime. SLS ain't going there. FH with Raptor US may well land humans there before SLS carries its first human aloft. It is time to let go of the past and embrace the future. SpaceX is that future.
Title: Re: SLS General Discussion Thread 2
Post by: TrevorMonty on 05/15/2016 07:01 PM
The SLS does have missions, after first 2-3 shake down  flights. They will do extended missions in cislunar space with EAM, this has been given initial funding.

Going back to moon will then be a option, at least transport will exist.

Title: Re: SLS General Discussion Thread 2
Post by: TomH on 05/15/2016 09:34 PM
The SLS does have missions, after first 2-3 shake down  flights. They will do extended missions in cislunar space with EAM, this has been given initial funding.

I'm sorry, just floating around in space somewhere in the vicinity of the moon does not qualify as a mission following what I observed in my teens, half a century ago. That notion is just downright sad.

I want to move forward; this is only moving backwards.
Title: Re: SLS General Discussion Thread 2
Post by: jtrame on 05/15/2016 09:40 PM
At least we're going from "it will never fly" to "ok, it will fly, but just once.  Maybe twice. But not more than 10 or 20 times.  That much is certain."
Title: Re: SLS General Discussion Thread 2
Post by: rayleighscatter on 05/15/2016 10:58 PM
I want to move forward; this is only moving backwards.
While this thread continues to go in circles.
Title: Re: SLS General Discussion Thread 2
Post by: Coastal Ron on 05/16/2016 01:06 AM
Flight metal is being bent, the SLS/Orion stack will fly BEO unmanned in late 2018 ( assuming a successful launch! ) and BFR will not even be past PDR and may never make it beyond Powerpoint .

I am a SpaceX fan, but I don't see anything SpaceX is doing now or in the future to be in "competition" with the SLS.

Why?  In order to have a competition there has to be something to compete for, and so far there is really nothing.  Sure, a few things are being considered, and mandated specifically and only for the SLS.  But otherwise there are no long-term U.S. Government plans or programs for SpaceX or anyone else to compete for.

And Congress is not basing their decision to fund the SLS based on what SpaceX does or doesn't do.  I can pretty much guarantee you that.

Quote
SLS is a heavy lift tool, it is up to future administrations to decide if and how it will be used.

That is bassackwards.  That is the "build it and they will come" way of spending taxpayer money, and the success rate of such attempts is not good.

Quote
But if it is used it can plug into many exploration architectures - both alone or in concert with commercial - as the first element of moving big stuff upstairs.

The SLS is a U.S. Government-only asset.  It won't be used by other countries, and it is unlikely that commercial needs for such a vehicle would appear before the next President assesses the future of the SLS.

Quote
Be thankful that serious talk of BEO is happening now, it has been a long time coming for us true believers and might still die on the vine ...

There is no serious talk, only talk.  And not enough being talked about to fill up the SLS operational launch schedule.

Plus, as many of us in the space community who advocate for expanding humanity out into space know, cost is the most important factor, not payload size.  So in order for the SLS to survive a review by the next President, there needs to be a significant need for it's unique capabilities - and there needs to be enough money allocated by Congress in order to support it.

We'll see if that happens...
Title: Re: SLS General Discussion Thread 2
Post by: notsorandom on 05/16/2016 03:52 PM
Agreed, SLS is perfectly scaled for a lunar program and would be an enabler for a manned return to the moon. It's too expensive to go to Mars with expendables but you can go to the moon with expendables. Why not? It would justify SLS having a flight rate of value, without requiring so many launches that it should be bank breaking beyond what SLS already is.  SLS at least makes an Apollo-like program repeatable, certainly enables large payloads to cislunar and perhaps even a minor lunar surface outpost.

However, it's not going to be used for any of those things yet, which is eyewatering. I can see a shift to lunar for SLS happening eventually, but it's not going to happen in this tumultuous year.
I'm quoting this post again because I've had a little more time to think about the Moon vs Mars debate in the context of SLS. I don't think the operational and launch costs of SLS are really what drives the choice of destination, at least not any more than any other expendable or even reusable launcher. The Moon is just so much cheaper that NASA can go back to the Moon with a reasonable budget in a reasonable amount of time with or without SLS consuming funds. Additionally even if the launch vehicles were free NASA would still not be in much better shape to go to Mars.

The Moon is easy enough, just need a lander. A while back Bolden told Congress that would cost $8 billion. When he said that many said he was being overly pessimistic but lets just go with that for now. I think an application of the lessons learned from the commercial crew program could bring that down significantly. So to put someone on the surface of the Moon by 2025 roughly a billions dollars at most is needed on average per year. It isn't too difficult to play with NASA's budget come up with the funds with or without SLS, especially if Congress kicks in a bit more money.

NASA is not planning on anyone setting foot on Mars until some time after 2030. It is also not clear where the funds to do that are going to come from. Some optimism is needed to see a future funding scenario that supports that. Eliminating SLS will free about $1.5-2 billion a year. Though some of that money will need to be invested in replicating SLS's capability, paying for facilities the SLS program covers but still need to be paid for, and some may just evaporate from NASA's budget. Even if it is as high as an extra billion a year is that all the difference between NASA being able to go to Mars and not being able to do so in a realistic amount of time?

SpaceX says that in the same time frame they will be going to Mars. If so then SLS will be obsolete in that regard, but so will everything else NASA is doing. If that is an argument for canceling SLS then it is an argument for canceling all of NASA's BEO plans that don't explicitly help or fund SpaceX.
Title: Re: SLS General Discussion Thread 2
Post by: Coastal Ron on 05/17/2016 09:35 PM
The Moon is just so much cheaper that NASA can go back to the Moon with a reasonable budget in a reasonable amount of time with or without SLS consuming funds.  Additionally even if the launch vehicles were free NASA would still not be in much better shape to go to Mars.

The cost driver of going to any destination is not really the cost of the transportation.  It's everything else.

Quote
The Moon is easy enough, just need a lander.

If all you want to do is just land there and then come back.  Like repeating Apollo 11.

Quote
A while back Bolden told Congress that would cost $8 billion. When he said that many said he was being overly pessimistic but lets just go with that for now.

I think that actually low based on using these two NASA programs as a reference:

1.  Mars Science Laboratory (MSL) - cost $1.5B and took 7 years from proposal to launch.

2.  The Orion spacecraft, which will be human-rated, will have taken at least $8B and 18 years by the time it becomes operational.

Quote
I think an application of the lessons learned from the commercial crew program could bring that down significantly. So to put someone on the surface of the Moon by 2025 roughly a billions dollars at most is needed on average per year. It isn't too difficult to play with NASA's budget come up with the funds with or without SLS, especially if Congress kicks in a bit more money.

Those in Congress that support NASA-owned hardware do not like the Commercial Cargo & Crew programs.  Obama had to fight hard for Commercial Crew, and it is unlikely the political dynamics will change.

And the calculus you leave out of all of this is that you only quote costs for a single barebones mission, yet the hardware architecture you talk about it is oriented towards a long-term effort.  That doesn't add up.

You are totally underestimating the cost of NASA "going back to the Moon".

Quote
NASA is not planning on anyone setting foot on Mars until some time after 2030.

Let's be honest here.  At it's current budget levels NASA will never get to Mars as part of a NASA-only effort.  Never.

And there is no government mandate for NASA to send humans to Mars.  Everything NASA has done to date has been part of "science", but going to Mars will have to be a political decision.

Quote
SpaceX says that in the same time frame they will be going to Mars. If so then SLS will be obsolete in that regard, but so will everything else NASA is doing.

Not at all.  NASA's goals are not the same as SpaceX, and NASA's goals today barely touch on sending humans to other planets.  There is not a lot of overlap.

Quote
If that is an argument for canceling SLS...

It's not.  The SLS is a U.S. Government-only transportation system, so the only reason to build it is if the U.S. Government has a sustained need for it's unique capabilities.  So far that has not proven to be a correct assumption, thus the questions for why we are building it.  "Build it and they will come" is not a justification, it's a wish...
Title: Re: SLS General Discussion Thread 2
Post by: spacenut on 05/17/2016 10:36 PM
I believe SLS is overkill for even the moon.  With fuel depots, and SEP tugs, and moon infrastructure can be built using existing EELV's and F9 and Falcon Heavies.  This at a lower cost per/kg of material sent to L1 or to the moon.  The money spent on one SLS launch could be spent building and supplying the moon infrastructure, using commercial bidders.  A new metholox upper for Falcon Heavy, and ACES for the upcoming Vulcan.  Together both launch providers could supply this infrastructure.

Maybe SLS could launch a larger Mars Lander that could be refueled in LEO by fuel depots.  Even then using the Vulcan and FH NASA could build a NautilusX type Mars transporter with landers.  All the money supporting and launching SLS could build both moon centric and Mars centric infrastructure.  Over $1 billion per launch for 105 tons to LEO.  A Vulcan with ACES plus a FH with metholox upper (engine being developed) could launch over 105 tons for less than half the price. 
 
Title: Re: SLS General Discussion Thread 2
Post by: edkyle99 on 05/18/2016 03:14 AM
I believe SLS is overkill for even the moon.  With fuel depots, and SEP tugs, and moon infrastructure can be built using existing EELV's and F9 and Falcon Heavies.  This at a lower cost per/kg of material sent to L1 or to the moon.  The money spent on one SLS launch could be spent building and supplying the moon infrastructure, using commercial bidders.  A new metholox upper for Falcon Heavy, and ACES for the upcoming Vulcan.  Together both launch providers could supply this infrastructure.

Maybe SLS could launch a larger Mars Lander that could be refueled in LEO by fuel depots.  Even then using the Vulcan and FH NASA could build a NautilusX type Mars transporter with landers.  All the money supporting and launching SLS could build both moon centric and Mars centric infrastructure.  Over $1 billion per launch for 105 tons to LEO.  A Vulcan with ACES plus a FH with metholox upper (engine being developed) could launch over 105 tons for less than half the price. 
 
You write this comparison as if the "fuel depots, ... SEP tugs, .... moon infrastructure", and "metholox upper stage for Falcon Heavy" cost nothing.  Those items will cost billions of dollars themselves.  I think you may also be positing a Vulcan Heavy, which is not being developed.

 - Ed Kyle
Title: Re: SLS General Discussion Thread 2
Post by: spacenut on 05/18/2016 04:20 AM
The billions spent on SLS could have been spent on this infrastructure instead using existing or with a little upgrading existing upgraded rockets.  Yes, there would be a lot of in space assembly, but that keeps everyone busy instead of one launch a year.  I mentioned Vulcan with ACES, which in itself is a heavy launcher, I think was 40 tons with solids.  I think in hindsight, upgrading the EELV's like Atlas V to heavy version or a 5m phase II version with ACES, then add the heavy option would have been cheaper and would have been a 50 ton launcher.  Of course now the "Russian" engines. 

Had NASA went with the original plan of 4 segment boosters, SSME's, and spent the money making an air startable SSME or RS-25 version air startable, then it would have been cheaper and gotten the same results.  The money spent on the solids making them 5 segments, was very expensive, for little results.  The infrastructure was already in place for the 4 segments even refurbishment.  Seem's like NASA has spent so much money doing studies, then even going so far as developing engines, never to be used like J2X, then congress getting involved.  I see now then using private companies, and bidding it gets far better results.  Government bureaus can and are very expensive, wasteful, and it's makes a camel in committees, when they could use a horse.  NASA has become just like other government agencies who make things in certain congressional districts and states just to get the money, even if it is more expensive.  It is not the stay focused NASA of the 60's I grew up with. 
Title: Re: SLS General Discussion Thread 2
Post by: Ben the Space Brit on 05/18/2016 02:48 PM
I'd like for any lunar lander to be a surface access system. There would be a common descent stage with either a crew ascent stage, a cargo hopper (which would double as a small pressurised rover garage) or a hab module. The objective being to enable extended lunar surface sorties of >1 lunar day, exploring large chunks of the surface. It could also be used to establish an outpost not dissimilar to the one at the South Pole here on Earth.

It occurs to me that, with SpaceX planning to at least look at fully-propulsive Mars EDL, you could at least think of using the common descent stage, with better engines and supersonic drogue parachutes, as a cargo delivery system for Mars too.

The credo is to use as few common spaceframes for as many applications as possible. It means reduced efficiency (as you'll not be optimising for the environment of just one target body) but you'll be balancing that with not having to design and prove a whole new vehicle for every new destination.
Title: Re: SLS General Discussion Thread 2
Post by: ncb1397 on 05/18/2016 06:17 PM
It's not.  The SLS is a U.S. Government-only transportation system, so the only reason to build it is if the U.S. Government has a sustained need for it's unique capabilities.  So far that has not proven to be a correct assumption, thus the questions for why we are building it.  "Build it and they will come" is not a justification, it's a wish...

Shuttle was a U.S. Government transportation system and it launched payloads provided by other countries. Why was Shuttle not U.S. Government only while SLS that is being operated the same way will be?

To be frank, the U.S. government doesn't have a need for much of anything NASA does. It is discretionary spending. Why is NASA building a Mars 2020 rover? All government programs can be questioned on an absolute need basis. It is like Jenga, you can take out individual pieces and the whole thing doesn't collapse.
Title: Re: SLS General Discussion Thread 2
Post by: edkyle99 on 05/18/2016 07:11 PM
The billions spent on SLS could have been spent on this infrastructure instead using existing or with a little upgrading existing upgraded rockets.  Yes, there would be a lot of in space assembly, but that keeps everyone busy instead of one launch a year.
SLS is costing about $10 billion in development up to its first launch.  That's a bargain!  NASA is spending $6.8 billion to develop commercial crew during the same time frame, just to get to ISS.  The ISS program itself costs NASA something like $3.9 billion per year, nearly twice as much as SLS is getting each year.  Should we end ISS too and give the money to SpaceX?

We've all known that existing launch vehicles could get humans to the Moon.  Griffin said as much, and I even advocated such an idea  ( http://www.spacelaunchreport.com/moonslo.html ), but SLS isn't going to the Moon.  NASA's Mars DRM 5.0 called for nine Ares 5 launches for a single mission to the Red Planet.  The rocket that will get humans to Mars has to be big.  SpaceX itself is not planning to use Falcon Heavy for humans to Mars.

 - Ed Kyle
Title: Re: SLS General Discussion Thread 2
Post by: Coastal Ron on 05/18/2016 09:02 PM
Shuttle was a U.S. Government transportation system and it launched payloads provided by other countries.

Co-manifested maybe, but I just looked through the Shuttle mission history and I didn't see any foreign government or foreign corporation payloads that were the primary payloads.  The vast majority of missions were for the U.S. Government.

Quote
Why was Shuttle not U.S. Government only while SLS that is being operated the same way will be?

The government cannot compete with the private sector - that is against the law.  So if the U.S. Government wants to sell launch services it has to charge fair market value, meaning a likely $1B+ per launch.  Who can afford that amount of money for one launch?

For instance, any european country that wants to send lots of mass into space will be forced politically to consider their domestic launch capabilities, and the first question will be to ask if the ultimate need can be broken down into payloads that can fit on those domestic launchers.  No doubt they can, and keeping the money "in-house" means they can spend more than if they use NASA.

It's hard to see a scenario where another country wants to pay for SLS launches.

Quote
To be frank, the U.S. government doesn't have a need for much of anything NASA does. It is discretionary spending. Why is NASA building a Mars 2020 rover?

We Americans have a history of supporting "science", and that is what our current space program is focused on, both for the ISS and for our robotic missions.

However sending humans to Mars, or back to the Moon, is more than "science", it's a prelude to colonization, and that is not yet supported politically.  There needs to be a national conversation about our goals for sending humans to space, but so far no one has decided to start that conversation.

And it could turn out that politically no one wants to support government-funded colonization of space.

But "science" is still likely to be supported.  Unfortunately that is not enough demand to support the need for a dedicated government-owned HLV.
Title: Re: SLS General Discussion Thread 2
Post by: A_M_Swallow on 05/18/2016 10:08 PM

We Americans have a history of supporting "science", and that is what our current space program is focused on, both for the ISS and for our robotic missions.

However sending humans to Mars, or back to the Moon, is more than "science", it's a prelude to colonization, and that is not yet supported politically.  There needs to be a national conversation about our goals for sending humans to space, but so far no one has decided to start that conversation.

And it could turn out that politically no one wants to support government-funded colonization of space.

But "science" is still likely to be supported.  Unfortunately that is not enough demand to support the need for a dedicated government-owned HLV.

Within about 2 years the world will see American landers on the Moon and manned US spacecraft docking to the ISS. This will bring up obvious questions like return to the Moon and a Moon Base. NASA needs to be ready with the obvious answers.

Manned landings appear to be possible in the new president's second term.

What design of launch vehicle and reentry capsule are used to get astronauts to the Deep Space Habitat in lunar orbit has not yet been decided.
Title: Re: SLS General Discussion Thread 2
Post by: QuantumG on 05/18/2016 10:12 PM
Within about 2 years the world will see American landers on the Moon and manned US spacecraft docking to the ISS.

... and people wonder why I'm cynical.

We've been hearing these claims for years now. Still waiting.

Title: Re: SLS General Discussion Thread 2
Post by: A_M_Swallow on 05/18/2016 11:04 PM
Within about 2 years the world will see American landers on the Moon and manned US spacecraft docking to the ISS.

... and people wonder why I'm cynical.

We've been hearing these claims for years now. Still waiting.



This is off topic for SLS.
Your waiting will soon be over. Delays are now due to problems found when testing prototype hardware.

I will allow the Commercial Crew supporters to speak for the ISS programs.

The Critical Design Review (CDR) on the Astrobotic Technology cargo lander is due next month (June 2016).

Something to watch
https://www.youtube.com/watch?v=ER3Nn_2mTjI (https://www.youtube.com/watch?v=ER3Nn_2mTjI)
Title: Re: SLS General Discussion Thread 2
Post by: spacenut on 05/19/2016 02:34 AM
How much per launch would the SLS cost if they launched say 4 per year? 
Title: Re: SLS General Discussion Thread 2
Post by: Proponent on 05/19/2016 08:00 AM
The billions spent on SLS could have been spent on this infrastructure instead using existing or with a little upgrading existing upgraded rockets.  Yes, there would be a lot of in space assembly, but that keeps everyone busy instead of one launch a year.
SLS is costing about $10 billion in development up to its first launch.  That's a bargain!  NASA is spending $6.8 billion to develop commercial crew during the same time frame, just to get to ISS.  The ISS program itself costs NASA something like $3.9 billion per year, nearly twice as much as SLS is getting each year.

If we're going to compare NASA-managed programs with commercially-managed ones, let's make it as apples-to-apples as we can.  If SLS costs $10 billion to first flight, Falcon Heavy will cost far less to the same milestone.  And if we count only cost to the US government, Falcon Heavy will be far, far cheaper than SLS.  SLS Block 1 is more capable, to be sure, but not in proportion to its cost.  As for crew capsules, Orion will be over $17 billion to first crewed flight (http://www.nasaspaceflight.com/2015/09/orion-passes-kdp-c-cautious-2023-crew-debut), ignoring the costs of its service module.  And that's assuming it flies in 2021, which is unlikely.  Compare that with the two commercial-crew vehicles.  And they're both more capable than Orion is without its service module and have lower recurring costs.  The Space Access Society has put out a comparison of the prices of the two programs (http://www.space-access.org/updates/sau147.html): Orion/SLS does not come out looking good (discussion here (https://forum.nasaspaceflight.com/index.php?topic=38187.msg1423497#msg1423497) and following).

Quote
Should we end ISS too and give the money to SpaceX?

Of course not.  What the government should do is decide what it needs to achieve its objectives (presumably go to Mars) and ask whether those needs are best met by the government or by American industry.  When it comes to launch services and crew transport, it appears that the question has not been asked.  Or if it has, the answer has been provided by legislative fiat.

Quote
We've all known that existing launch vehicles could get humans to the Moon.  Griffin said as much, and I even advocated such an idea  ( http://www.spacelaunchreport.com/moonslo.html ), but SLS isn't going to the Moon.  NASA's Mars DRM 5.0 called for nine Ares 5 launches for a single mission to the Red Planet.  The rocket that will get humans to Mars has to be big.  SpaceX itself is not planning to use Falcon Heavy for humans to Mars.

Yes, but SpaceX speaks of colonizing Mars, whereas NASA talks of sending a few astronauts per decade.  SpaceX has said that for sending a few astronauts, a Falcon Heavy-sized rocket will do. (https://forum.nasaspaceflight.com/index.php?topic=34856.msg1211693#msg1211693)  Maybe SpaceX is wrong, but the possibility should be seriously studied before being dismissed.  As far as I can tell, that has not happened.  And even if SpaceX is wrong, the possibility of buying heavy-lift launch services from American industry should be considered.  As far as I can tell, it has not.
Title: Re: SLS General Discussion Thread 2
Post by: Ben the Space Brit on 05/19/2016 10:45 AM

SLS is costing about $10 billion in development up to its first launch.  That's a bargain!  NASA is spending $6.8 billion to develop commercial crew during the same time frame, just to get to ISS. 

Apples to Oranges comparison. You're comparing the cost to get a launch vehicle with what verges on a dummy payload (and, let's not forget, a defunded U/S) to its first test launch to the cost of creating two crew-ready ETO transport systems practically from scratch.
Title: Re: SLS General Discussion Thread 2
Post by: spacenut on 05/19/2016 02:01 PM
Maybe the only way SLS costs per flight will come down is if ATK/Orbital develops the solid rocket based on the SLS boosters and shares the Kennedy space facilities and launch pad with NASA.  It might not be as cost competitive as either Vulcan or Falcon Heavy, but if it can help bring down the launch costs. 

I see the advantage SpaceX is using by incremental improvements over time, then going to their heavy version.  The Russian R-7/Soyuz had done the same.  This is the approach by using the old Direct method.  Sure the first version only got 70 tons to orbit, but it would have gotten us the ability to at least get to L1 or the Moon.  Then incremental improvements, one at a time, like 5 seg boosters, using an existing upper stage say from Delta IV to begin with, then stretch the core and add 5 engines, then develop the J2X upper stage, then the composite boosters or liquid boosters.  Not all at one time, but over time and use some money to begin deep space exploration/outposts/colonization. Lift capacity could gradually improve from say 70 tons to 150 tons with liquid boosters. 
Title: Re: SLS General Discussion Thread 2
Post by: notsorandom on 05/19/2016 02:04 PM
How much per launch would the SLS cost if they launched say 4 per year?
Its a simple question but I think everyone has their own answer depending on their opinion of SLS. Some like to throw in the development cost too. According to them SLS costs billions per launch. Others like to quote only the marginal cost, leaving out the yearly program support cost. From their viewpoint SLS cost about $300 million per launch.

My favored way to look at it is the entire yearly budget divided by the number of flights. The rocket is in development right now so its hard to say what the fixed or marginal costs will be. It is probably going to keep getting roughly the same budget each year so $2 billion might not be a bad guess. If they can launch 4 a year then a ball park figure is probably in the neighborhood of $500 million per launch give or take a lot. The program requirements are up to 3 launches a year. It has been debated if they can do more than that without too much difficulty.

In general since the fixed costs can be spread out over more launches the price per launch will keep decreasing as the number of launches increases. With a high fixed support cost two launches a year represents a substantial increase over just one launch a year in the price per kg.
Title: Re: SLS General Discussion Thread 2
Post by: spacenut on 05/19/2016 02:23 PM
The numbers I saw were between $1 to $1.3 billion for one launch per year, which includes marginal and fixed costs to operate.  That is why I was asking what would 3-4 per year cost.  If it costs $500 billion for 3 launches per year, then to me it would make sense to launch it 3 times a year for $1.5 billion vs $1.3 for one.  Then use the heavy lift to build a Mars transporter one year, fuel the thing the next and go to Mars.  Or, use the heavy lift to build an L1 or L2 gateway station for the moon or Mars.  Throw the money from the ISS to do this.  A station at L1 or L2 would be more exciting than a LEO station.  Falcon Heavies and future Vulcan's with ACES could bring astronauts to one of these stations without using SLS.  Or keep it supplied like they do now with ISS.  I also think you would get more international help/support or participation with something like this.  In space stations and equipment should be designed as modular and long lasting as possible.  At least 20 years or longer.  Components could be replaced with modular components instead of just crashing the thing like ISS to keep it going.  We build ships and planes to last 50 years or more.  Why not in space components and transportation systems. 
Title: Re: SLS General Discussion Thread 2
Post by: Graham on 05/19/2016 02:39 PM
We build ships and planes to last 50 years or more.  Why not in space components and transportation systems.

We build those ships and planes to last 50 years with the expectation that there are vast maintenance crews to keep them in shape. A team of engineers fixing something on Earth is much easier than it is for two astronauts in EMUs. And that's simple mechanical failures, there's also the simple fact that space is a far harsher environment. There is radiation and micrometeorite concern, and there's not a whole lot we can do about the latter. And on top of all that whatever gets launched has to fit within a fairing, not be over weight, and survive the environment of the launch.

One day our infrastructure in space will be good enough to allow things to regularly operate for 50 years, but in the foreseeable future it will be very difficult and expensive to do that. Just go look at the ISS status reports on L2 and see how much of the time the crew has to spend dealing with equipment issues.
Title: Re: SLS General Discussion Thread 2
Post by: edkyle99 on 05/19/2016 02:46 PM
I despise this argument to defund SLS.  The U.S. will need this world's-most-capable rocket to get humans to Mars.  It will also need Falcon Heavy and Vulcan Aces and Ariane 6 and whatever other launch vehicle is developed and available. 

This is no small task.  Thinking small won't get it done.  It will take the full might of the aerospace industry, marshaled by government. 

In my opinion.

 - Ed Kyle
Title: Re: SLS General Discussion Thread 2
Post by: the_other_Doug on 05/19/2016 02:53 PM
How much per launch would the SLS cost if they launched say 4 per year?
Its a simple question but I think everyone has their own answer depending on their opinion of SLS. Some like to throw in the development cost too. According to them SLS costs billions per launch. Others like to quote only the marginal cost, leaving out the yearly program support cost. From their viewpoint SLS cost about $300 million per launch.

My favored way to look at it is the entire yearly budget divided by the number of flights. The rocket is in development right now so its hard to say what the fixed or marginal costs will be. It is probably going to keep getting roughly the same budget each year so $2 billion might not be a bad guess. If they can launch 4 a year then a ball park figure is probably in the neighborhood of $500 million per launch give or take a lot. The program requirements are up to 3 launches a year. It has been debated if they can do more than that without too much difficulty.

In general since the fixed costs can be spread out over more launches the price per launch will keep decreasing as the number of launches increases. With a high fixed support cost two launches a year represents a substantial increase over just one launch a year in the price per kg.

Just a question to put things into perspective -- in 2016 dollars, how much did each Saturn V launch cost?  And how much did they cost expressed in the various ways you have given for SLS above?

My guess is that Saturn V was comparably more expensive per launch than SLS looks like it will be.  And except for 1969, it never was launched more than twice in any given calendar year -- in fact, it was launched once in 1967, twice in 1968, four times in 1969, once in 1970, twice in 1971, twice in 1972 and once in 1973.  Of those 13 launches, of course, 10 flew crews, nine flew crews to the Moon, and one flew with only its first two stages live.

It has always sounded to me like SLS was being designed for the average flight rate of the Saturn V, and thus I think a cost comparison would be illuminating...
Title: Re: SLS General Discussion Thread 2
Post by: Jim on 05/19/2016 02:58 PM
I despise this argument to defund SLS.  The U.S. will need this world's-most-capable rocket to get humans to Mars.  It will also need Falcon Heavy and Vulcan Aces and Ariane 6 and whatever other launch vehicle is developed and available. 

This is no small task.  Thinking small won't get it done.  It will take the full might of the aerospace industry, marshaled by government. 

That is why it is not going to happen.  US government is not going to fund manned mars missions.
Title: Re: SLS General Discussion Thread 2
Post by: Kansan52 on 05/19/2016 03:02 PM
Based on earlier posts, more production facilities would be needed to go beyond 2 launchers a years (and current production may actually do less than 2 a year). So it isn't just increasing the production rate but the cost of expanding production facilities.

But the likely costs per launch, based on STS, would approach $1 billion per launch. So 4 launches per year would be $4 billion. Plus, what would be launched? The current hole in the SLS program is the lack of payloads.

So scrapping the ISS would be a drop in the bucket to increase SLS launch rate and building the payloads.

The rest about building 50 year stations and the such is a whole other subject.

But the common thread is that to do all these things requires a larger budget. Moving money around from one program to another, even ending one program to benefit another, will not be enough.
Title: Re: SLS General Discussion Thread 2
Post by: Jim on 05/19/2016 03:04 PM

Within about 2 years the world will see American landers on the Moon

Nonsense.
a.  There are no NASA landers in design much less production
b.  There are no commercial ones even close to launching in that time frame  And if they did, they have no affect on NASA funding


Manned landings appear to be possible in the new president's second term.


The next president doesn't care about manned lunar missions.


What design of launch vehicle and reentry capsule are used to get astronauts to the Deep Space Habitat in lunar orbit has not yet been decided.

Because there is no Deep Space Habitat in lunar orbit program for astronauts to go to and there won't be one since the next president doesn't care about space
Title: Re: SLS General Discussion Thread 2
Post by: jtrame on 05/19/2016 03:06 PM
I despise this argument to defund SLS.  The U.S. will need this world's-most-capable rocket to get humans to Mars. 

US government is not going to fund manned mars missions.

My sense of it is that it will be an international effort like the ISS and the U.S. will fund part of it including the use of SLS for some of the heavy lifting.  That's just an opinion.  The scope of the project is so large it's hard to imagine one country taking it on alone.
Title: Re: SLS General Discussion Thread 2
Post by: the_other_Doug on 05/19/2016 03:20 PM
I despise this argument to defund SLS.  The U.S. will need this world's-most-capable rocket to get humans to Mars.  It will also need Falcon Heavy and Vulcan Aces and Ariane 6 and whatever other launch vehicle is developed and available. 

This is no small task.  Thinking small won't get it done.  It will take the full might of the aerospace industry, marshaled by government. 

In my opinion.

 - Ed Kyle

Jim's assumption aside (we've had thread after thread where he trots out his pet opinion that governments should have no role in manned solar system exploration), I will completely agree with you, Ed.  We will need all of the resources you mention to mount any manned BLEO expeditions.  All of the various commercial launchers and commercial satellite developers will have plenty of work in such efforts, if they want to bid for it.

I keep seeing this as a logical result of how such large projects must be funded in today's funding environment.  You just can't afford to do an Apollo-style program where all of the various elements are funded at the same time, all of which are scheduled to be complete and available for a series of scheduled and funded missions.

You have to develop the pieces serially and not in parallel, for the most part -- although there will obviously be overlaps.  The first piece to be developed for BLEO missions was the Earth-to-space-to-Earth shuttle vehicle -- Orion.  The second piece is SLS.  The third piece will be transit hab modules, and we are about to see contracts let to develop ground-based demo versions of trans habs.  If they do a good enough job, the demo vehicle(s) may even fly on ISS.

The fourth piece will be a higher-end ion propulsion unit (which has seen study contracts let over the past several years, so development contracts may be another two or three years out).  The fifth and final piece will be the mission-specific hardware.  That will always be the last piece, because you will vary that piece and use the first four pieces plus that specialized fifth element to accomplish different missions.  For example, you need a microgravity base station for a mission to an asteroid, or to Mars' moons, while you need a lander and a surface hab for Mars surface operations.

In my vision, building and launching pieces three, four and five are the areas where you're going to see commercial launch and spacecraft vendors coming to the fore.  You might see an ACES-based lander bringing a crew to the Martian surface, there to inhabit a Bigelow surface hab that was launched on a Falcon Heavy.   Lots of possible combinations.

But a lot of the pieces will require the SLS to get them off Earth, I am convinced.  It will be a needful part of any BLEO expeditions, at least IMHO...
Title: Re: SLS General Discussion Thread 2
Post by: Ben the Space Brit on 05/19/2016 03:21 PM
Don't forget that US support for the ISS only happened for solidly geopolitical reasons: the US didn't want bankrupt Russian aerospace firms selling their know-how to people like Saddam Hussein. There would need to be a similar overriding US national security motive for any government involvement in an accelerated Mars program.
Title: Re: SLS General Discussion Thread 2
Post by: Jim on 05/19/2016 05:30 PM

Jim's assumption aside (we've had thread after thread where he trots out his pet opinion that governments should have no role in manned solar system exploration),

The opinion also includes that the governments aren't going fund it anyways.  Almost 60 years since going to the moon and still have only words and no money to go back. 
Title: Re: SLS General Discussion Thread 2
Post by: jtrame on 05/19/2016 05:46 PM
Don't forget that US support for the ISS only happened for solidly geopolitical reasons: the US didn't want bankrupt Russian aerospace firms selling their know-how to people like Saddam Hussein. There would need to be a similar overriding US national security motive for any government involvement in an accelerated Mars program.

Whatever the reasons that got it built, I would hope the lesson learned from ISS would be that international cooperation in space exploration makes sense for a lot of reasons.  Cost being the biggest. 

Maybe it will be a smaller coalition, USA, ESA, JSA, etc.
Title: Re: SLS General Discussion Thread 2
Post by: A_M_Swallow on 05/19/2016 06:26 PM

Within about 2 years the world will see American landers on the Moon

Nonsense.
a.  There are no NASA landers in design much less production
b.  There are no commercial ones even close to launching in that time frame  And if they did, they have no affect on NASA funding

I wrote American not NASA. You obviously think the 3 commercial lunar cargo landers in Lunar CATALYST will take more than 2 years to complete.

If NASA can use a film about someone surviving on Mars in its budget request to Congress I suspect news headlines about rovers on the Moon can also be used.

http://www.nasa.gov/sites/default/files/files/3-Status_of_AES.pdf (http://www.nasa.gov/sites/default/files/files/3-Status_of_AES.pdf)

Quote

Manned landings appear to be possible in the new president's second term.


The next president doesn't care about manned lunar missions.


That is an opinion not a fact.

What candidates and presidents care about can change.

Quote


What design of launch vehicle and reentry capsule are used to get astronauts to the Deep Space Habitat in lunar orbit has not yet been decided.

Because there is no Deep Space Habitat in lunar orbit program for astronauts to go to and there won't be one since the next president doesn't care about space

This is the second year of NextSTEP. I am not giving up on it yet.
Title: Re: SLS General Discussion Thread 2
Post by: Kryten on 05/28/2016 02:04 PM
 Three more cubesats for EM-1, including a lander;
https://www.nasa.gov/exploration/systems/sls/international-partners-provide-cubesats-for-sls-maiden-flight
Quote
For the first SLS flight, the Japan Aerospace Exploration Agency (JAXA) and the University of Tokyo will jointly create and provide two CubeSats, EQUULEUS (EQUilibriUm Lunar-Earth point 6U Spacecraft) and OMOTENASHI (Outstanding MOon exploration TEchnologies demonstrated by NAno Semi-Hard Impactor). EQUULEUS will help scientists understand the radiation environment in the region of space around Earth by imaging Earth’s plasmasphere and measuring the distribution of plasma that surrounds the planet. This opportunity may provide important insight for protecting both humans and electronics from radiation damage during long space journeys. It will also demonstrate low-energy trajectory control techniques, such as multiple lunar flybys, within the Earth-Moon region.

JAXA also will use the OMOTENASHI to demonstrate the technology for low-cost and very small spacecraft to explore the lunar surface. This technology could open up new possibilities for future missions to inexpensively investigate the surface of the moon. The CubeSat will also take measurements of the radiation environment near the moon as well as on the lunar surface.
[...]
The Italian company Argotec is building the ArgoMoon CubeSat under the Italian Space Agency (ASI) internal review and approval process. ArgoMoon will demonstrate the ability to perform operations in close proximity of the Interim Cryogenic Propulsion Stage (ICPS), which will send Orion onto its lunar trajectory. It should also record images of the ICPS for historical documentation and to provide valuable mission data on the deployment of other Cubesats. Additionally, this CubeSat should test optical communication capabilities between the CubeSat and Earth.
Title: Re: SLS General Discussion Thread 2
Post by: woods170 on 05/28/2016 09:37 PM

Jim's assumption aside (we've had thread after thread where he trots out his pet opinion that governments should have no role in manned solar system exploration),

The opinion also includes that the governments aren't going fund it anyways.  Almost 60 years since going to the moon and still have only words and no money to go back. 
Correct. And anyone here who thinks this will change with the next president really ought to step out of phantasy-land.
Title: Re: SLS General Discussion Thread 2
Post by: oldAtlas_Eguy on 05/29/2016 09:11 PM

Jim's assumption aside (we've had thread after thread where he trots out his pet opinion that governments should have no role in manned solar system exploration),

The opinion also includes that the governments aren't going fund it anyways.  Almost 60 years since going to the moon and still have only words and no money to go back. 
Correct. And anyone here who thinks this will change with the next president really ought to step out of phantasy-land.
Ah... 1969+60=2029
It actually has been since first man on the Moon 47 years. I think you meant almost 50 years. But you are right it has been a long time with plenty of opportunity to fund a new Moon landing program, but for some reason they just can't sustain any funding if they get funded at all.
Title: Re: SLS General Discussion Thread 2
Post by: JDTractorGuy on 05/30/2016 01:43 PM
Just curious, if by some miracle the next administration decided to double funding for SLS/Orion, how would that impact the launch rate and the launch dates of EM-1/EM-2? 
Title: Re: SLS General Discussion Thread 2
Post by: gospacex on 05/30/2016 01:52 PM
I despise this argument to defund SLS.  The U.S. will need this world's-most-capable rocket to get humans to Mars.  It will also need Falcon Heavy and Vulcan Aces and Ariane 6 and whatever other launch vehicle is developed and available. 

This is no small task.  Thinking small won't get it done.  It will take the full might of the aerospace industry, marshaled by government. 

In my opinion.

 - Ed Kyle

Jim's assumption aside (we've had thread after thread where he trots out his pet opinion that governments should have no role in manned solar system exploration), I will completely agree with you, Ed.  We will need all of the resources you mention to mount any manned BLEO expeditions.  All of the various commercial launchers and commercial satellite developers will have plenty of work in such efforts, if they want to bid for it.

I keep seeing this as a logical result of how such large projects must be funded in today's funding environment.  You just can't afford to do an Apollo-style program where all of the various elements are funded at the same time, all of which are scheduled to be complete and available for a series of scheduled and funded missions.

You have to develop the pieces serially and not in parallel

No. Instead, you have to stop giving money for this development to the organization which only ever pulled off one Apollo-style development program, and had a string of failures (or worse - "successes" so financially devastating they kept the entire manned program stagnant for 40 years) ever since.

Apollo program was a success in a sense that US did beat Soviets to the Moon.

However, when you look at it from the point of view of developing a healthy space program, it looked decidedly warped.

Think about it.

Driving *five thousand 50-meter long steel piles* into Florida sands *only to build a vehicle assembly building*? That's madness.

Rolling out and moving several miles 363 feet tall LV *vertically*? You got to be kidding me!

I'm not saying Apollo program was flawed. I'm saying it was optimized for a goal which made it unsustainable, and led to cancellation.

Worse, it created a whole generation of NASA people who don't even understand that that's a *wrong* way to develop a space program.

If you stop giving R&D money to NASA and start giving them to competing private companies, you can afford to develop things in parallel.
Title: Re: SLS General Discussion Thread 2
Post by: AncientU on 05/30/2016 02:45 PM
I despise this argument to defund SLS.  The U.S. will need this world's-most-capable rocket to get humans to Mars.  It will also need Falcon Heavy and Vulcan Aces and Ariane 6 and whatever other launch vehicle is developed and available. 

This is no small task.  Thinking small won't get it done.  It will take the full might of the aerospace industry, marshaled by government. 

In my opinion.

 - Ed Kyle

While I agree with this all-in approach, two features of your argument are troubling. 

First, SLS is implied as the 'world's most capable rocket.'  FH (with either the 1.7M or 1.9Mlbf thrust booster version) will lift more payload than SLS's first 'block' as shown by your and others' calculations.  SLS will first be flown in 2019 or so, and then have a second experimental flight several years later; FH will fly several times per year from 2017 on, and is capable of flying roughly monthly from either of two sites (three by 2019 or so).  In reusable mode, it could put roughly six SLS payload mass equivalents into LEO per launch site per year -- for the cost of one expendable SLS.  By the twenty-thirties when SLS is finally capable of approximating Saturn V's payload (again by your calculations, it will never reach the advertised 130tonnes) it still is unlikely to be the 'world's most capable rocket.'   I think it will be cancelled long before that due to it's own inadequacies and cost, not the small voice those of us who would choose to defund it...

Second, massive funding for an old technology, expendable rocket that has so little lift capability (it will *eventually* have a big fairing which some carrier rocket will have to incorporate), and even less capability to be mass produced/frequently launched, is standing in the way of putting people on Mars more than aiding it.  The full might of the (traditional) aerospace industry is marshaled and lobbying for it.

I'm afraid 'thinking small' is what NASA, Congress, and many on this forum are currently doing. 
I'd suggest that a reusable 'world's most capable rocket' is the only way we're going to get to Mars.
Title: Re: SLS General Discussion Thread 2
Post by: edkyle99 on 05/30/2016 03:49 PM
First, SLS is implied as the 'world's most capable rocket.'  FH (with either the 1.7M or 1.9Mlbf thrust booster version) will lift more payload than SLS's first 'block' as shown by your and others' calculations. 
This is simply incorrect.  SLS Block 1 will boost 24.5 tonnes toward the Moon.  (It could, if needed, lift more than 90 tonnes to low earth orbit (70 tonnes is an artifact of the old SLS Block 0 design), but SLS is never going to LEO so that number is irrelevant.)  Falcon Heavy, even in full-expendable mode, would boost probably about 15 tonnes (plus or minus) toward the Moon.  (Falcon Heavy is also listed at only 54.4 tonnes to LEO in full-expendable mode.)

It would take three fully-expendable Falcon Heavies to match the payload of one SLS Block 1B trans-Mars.  It would take four Falcon Heavies to match one SLS Block 2.  I expect that Falcon Heavy and/or others like it will be needed to support deep-space missions, but the missions will be built around the unparalleled deep space throw-weight offered by SLS. 

 - Ed Kyle
Title: Re: SLS General Discussion Thread 2
Post by: ThereIWas3 on 05/30/2016 04:01 PM
It would take three fully-expendable Falcon Heavies to match the payload of one SLS Block 1B trans-Mars.  It would take four Falcon Heavies to match one SLS Block 2.  I expect that Falcon Heavy and/or others like it will be needed to support deep-space missions, but the missions will be built around the unparalleled deep space throw-weight offered by SLS. 

An affordable launcher that can lift smaller payloads is more useful than a big one that is too expensive to operate.  In times of tight money, you can scale back to fewer loads, but at least you are making some progress.   With a big rocket either you can afford the full load or you lauch nothing at all.  Money is too tight right now, and I do not see it becoming easier to get out of Congress for elective projects like this.

When building a house, the materials are not delivered all  at once on one huge truck.  Even if you could do it, you would not be ready to use it.  I watched a house near me being built, and due to some scheduling problem the load of pre-assembled roof trusses was delivered before the foundation was poured.  All that unprotected wood sat out in the rain, and was in the way of subsequent deliveries.
Title: Re: SLS General Discussion Thread 2
Post by: edkyle99 on 05/30/2016 07:26 PM
An affordable launcher that can lift smaller payloads is more useful than a big one that is too expensive to operate.  In times of tight money, you can scale back to fewer loads, but at least you are making some progress.   
I disagree with your assertion that SLS is "too expensive to operate".  It is being designed to operate on less than the Shuttle budget, involving far fewer workers.  Shuttle flew for three decades.

 - Ed Kyle
Title: Re: SLS General Discussion Thread 2
Post by: A_M_Swallow on 05/30/2016 08:30 PM
An affordable launcher that can lift smaller payloads is more useful than a big one that is too expensive to operate.  In times of tight money, you can scale back to fewer loads, but at least you are making some progress.   
I disagree with your assertion that SLS is "too expensive to operate".  It is being designed to operate on less than the Shuttle budget, involving far fewer workers.  Shuttle flew for three decades.

 - Ed Kyle

Shuttle was not competing for missions with Dragon, CST-100 and Dream Chaser.
Title: Re: SLS General Discussion Thread 2
Post by: Dasun on 05/30/2016 09:10 PM
Sigh, and SLS is not competing for missions with FH, Dragon, CST-100 and Dream Chaser!!!

SLS was designed, based on NASA requirements,  to support likely Mars mission architectures at relatively low flight rates.  SLS (and NASA) is not in competition with SpaceX - in fact SpaceX is just another aerospace contractor that can meet NASA needs.  Congress seems to have some firm ideas what SLS is going to do - DSH and Luna - in the next decade, lets us see if the money flows and the next POTUS agrees. 
Title: Re: SLS General Discussion Thread 2
Post by: gospacex on 05/30/2016 09:30 PM
SLS (and NASA) is not in competition with SpaceX.

Except that SLS *is* in competition with SpaceX.

By law, NASA can't compete with commercially available products.

As soon as FH flies, some difficult questions will be asked, "why do we pay these insane money for SLS?"
Title: Re: SLS General Discussion Thread 2
Post by: Dasun on 05/30/2016 09:34 PM
FH does not compete with SLS - It throws much more upstairs !!!! And I think you will be waiting quite awhile for your "difficult" questions to be asked at the appropriate level for influence to happen!!
Title: Re: SLS General Discussion Thread 2
Post by: IRobot on 05/30/2016 09:50 PM
SLS (and NASA) is not in competition with SpaceX.

Except that SLS *is* in competition with SpaceX.

By law, NASA can't compete with commercially available products.

As soon as FH flies, some difficult questions will be asked, "why do we pay these insane money for SLS?"
For the moment NASA can claim FH does not have a large enough fairing and that the overall GTO performance is lower.

When and if BFR starts flying, SLS is dead.
Title: Re: SLS General Discussion Thread 2
Post by: Coastal Ron on 05/30/2016 09:50 PM
Sigh, and SLS is not competing for missions with FH, Dragon, CST-100 and Dream Chaser!!!

I would agree with that.

Quote
SLS was designed, based on NASA requirements...

No, NASA was not involved in defining the SLS.  The Senators that wrote S.3729, and their advisors (which supposedly included former NASA Administrator Michael Griffin), created the specs without NASA involvement or coordination.

Quote
...to support likely Mars mission architectures at relatively low flight rates.

Supposedly, but of course Congress has never funded such efforts.

Quote
...in fact SpaceX is just another aerospace contractor that can meet NASA needs.

Maybe it's semantics, but a contractor builds what you need according to your specs.  A service provider already has a service that you require, even if it needs to be tweaked or modified for your requirements.  Based on that, to me SpaceX would be classified as a service provider.

Quote
Congress seems to have some firm ideas what SLS is going to do...

"Congress" is composed of 100 Senators from 50 different states, and 435 Representatives from 435 political districts around the U.S.

The only certain way to know what Congress "wants" is to see what they vote for.  And so far they have not voted to fund any long-term programs that would require the unique services of the government-owned transportation system known as the SLS.

Maybe you have heard individual members of Congress express interest or desire for tasks the SLS would be suited for, but until they put it into legislation for all of Congress to vote on, it doesn't mean anything.

Quote
...lets us see if the money flows and the next POTUS agrees.

Yep.  Because nothing will be added this year.
Title: Re: SLS General Discussion Thread 2
Post by: AncientU on 05/30/2016 11:22 PM
First, SLS is implied as the 'world's most capable rocket.'  FH (with either the 1.7M or 1.9Mlbf thrust booster version) will lift more payload than SLS's first 'block' as shown by your and others' calculations. 
This is simply incorrect.  SLS Block 1 will boost 24.5 tonnes toward the Moon.  (It could, if needed, lift more than 90 tonnes to low earth orbit (70 tonnes is an artifact of the old SLS Block 0 design), but SLS is never going to LEO so that number is irrelevant.)  Falcon Heavy, even in full-expendable mode, would boost probably about 15 tonnes (plus or minus) toward the Moon.  (Falcon Heavy is also listed at only 54.4 tonnes to LEO in full-expendable mode.)

It would take three fully-expendable Falcon Heavies to match the payload of one SLS Block 1B trans-Mars.  It would take four Falcon Heavies to match one SLS Block 2.  I expect that Falcon Heavy and/or others like it will be needed to support deep-space missions, but the missions will be built around the unparalleled deep space throw-weight offered by SLS

 - Ed Kyle

The unparalleled throw weight offered by SLS will be paralleled and exceeded by an architecture that includes refueling on orbit.  Problem with SLS is it was created in the Apollo paradigm -- a paradigm which does not work for Mars.  NASA's own plans require dozens of SLS launches to assembly the pieces for a minimal Human mission to Mars.  You simply must launch early and often, which SLS will never do.

54.4 tonnes to LEO is simply not consistent with three 1.7-1.9Mlbf stages -- that's 2/3rds to 3/4ths of Saturn V liftoff thrust -- even a single core (skinny) F9 outperforms Saturn V in PMF (and delivers double the PMF of SLS).  FH outperforms F9 by a significant margin.  Then cross feed and Raptor powered second stage can be added just as Block 2 will eventually get a better second stage and new boosters.

At $3-4B per year, we are (NASA and Congress are) throwing away our opportunity to go to Mars by betting on a minimally capable launch system and unworkable architecture.  We will see which architecture actually gets us there.
Title: Re: SLS General Discussion Thread 2
Post by: spacenut on 05/30/2016 11:27 PM
Money can't flow unless the economy improves with jobs that create taxpayers (private enterprise jobs).  I'm afraid NASA is not going to get much of a budget increase in the next few years UNLESS the economy improves.  We are about $20 trillion in debt and it can't be kicked down the road forever.  Something has to give sooner or later.  NASA has been plodding along putting one foot in front of the other, while private companies like SpaceX and Blue Origin are making strides in recovery and increased payloads to orbit at LOWER costs.  So has Orbital and now ATK is proposing a new three stage solid to increase payloads at lower costs.  Mars can be done with 20 ton payloads, lots of them, but less than half that many payloads with 40-50 ton payloads from Falcon Heavy and the future Vulcan with ACES.  SLS can only lift about 100 tons to LEO, and they still need an upper stage for deep space probes and operations. 

The cost of SLS can come down IF they launch 3 per year or more, but not at one per year.  There is no vision from the president or a presidential candidate yet.  Without a vision and a goal, SLS will be dead as far as humans going to Mars with only one launch a year. 
Title: Re: SLS General Discussion Thread 2
Post by: edkyle99 on 05/30/2016 11:59 PM
54.4 tonnes to LEO is simply not consistent with three 1.7-1.9Mlbf stages -- that's 2/3rds to 3/4ths of Saturn V liftoff thrust -- even a single core (skinny) F9 outperforms Saturn V in PMF (and delivers double the PMF of SLS).  FH outperforms F9 by a significant margin.  Then cross feed and Raptor powered second stage can be added just as Block 2 will eventually get a better second stage and new boosters.
54.4 tonnes is what the manufacturer says Falcon Heavy can do.  If would lift half that, give or take, if the booster and first stages were recovered.  Your Saturn 5 liftoff thrust comparison doesn't add up because Saturn 5 used high energy liquid hydrogen fueled upper stages.  Falcon Heavy uses lower energy hydrocarbon engines on all of its stages.  It has to carry a heavier upper stage, relatively speaking, to make up the difference.  More liftoff thrust, relatively speaking, is needed to lift the extra mass. 

The key number is Falcon Heavy's 13.6 tonnes trans-Mars (full-expendable).  That's impressive, and can be exploited any number of ways, but it isn't 40 tonnes or 46 tonnes (SLS Block 1B Cargo or SLS Block 2).

 - Ed Kyle
Title: Re: SLS General Discussion Thread 2
Post by: gospacex on 05/31/2016 12:15 AM
SLS (and NASA) is not in competition with SpaceX.

Except that SLS *is* in competition with SpaceX.

By law, NASA can't compete with commercially available products.

As soon as FH flies, some difficult questions will be asked, "why do we pay these insane money for SLS?"
For the moment NASA can claim FH does not have a large enough fairing...

...large enough *for what*? Can NASA point us to a funded payload which can't fit into FH's fairing?
Title: Re: SLS General Discussion Thread 2
Post by: llanitedave on 05/31/2016 04:11 AM
SLS (and NASA) is not in competition with SpaceX.

Except that SLS *is* in competition with SpaceX.

By law, NASA can't compete with commercially available products.

As soon as FH flies, some difficult questions will be asked, "why do we pay these insane money for SLS?"

No, it's not.  When/if SpaceX gets it's BFR operational and agrees to release it for NASA missions, then they can talk.  Until then, the SLS has its own market.
Title: Re: SLS General Discussion Thread 2
Post by: Coastal Ron on 05/31/2016 04:24 AM
The key number is Falcon Heavy's 13.6 tonnes trans-Mars (full-expendable).  That's impressive, and can be exploited any number of ways, but it isn't 40 tonnes or 46 tonnes (SLS Block 1B Cargo or SLS Block 2).

We're not going to expand humanity out into space by relying only on direct launch to the destination.  That is Apollo-style thinking, and Apollo only used that method for expediency, not because it was the best way.

Regardless the launchers used, we're going to be assembling spaceships and expeditions in local space before going into deep space.  We've already gained a lot of knowledge how to do this with the 450mT ISS, so we know it's well within our capabilities.  No need to throw away that knowledge and ability...
Title: Re: SLS General Discussion Thread 2
Post by: woods170 on 05/31/2016 09:09 AM
When and if BFR starts flying, SLS is dead.
Minor nit:
Only if SpaceX makes BFR commercially available.
Title: Re: SLS General Discussion Thread 2
Post by: Proponent on 05/31/2016 02:25 PM
54.4 tonnes is what the manufacturer says Falcon Heavy can do.  If would lift half that, give or take, if the booster and first stages were recovered.  Your Saturn 5 liftoff thrust comparison doesn't add up because Saturn 5 used high energy liquid hydrogen fueled upper stages.  Falcon Heavy uses lower energy hydrocarbon engines on all of its stages.  It has to carry a heavier upper stage, relatively speaking, to make up the difference.  More liftoff thrust, relatively speaking, is needed to lift the extra mass. 

The key number is Falcon Heavy's 13.6 tonnes trans-Mars (full-expendable).  That's impressive, and can be exploited any number of ways, but it isn't 40 tonnes or 46 tonnes (SLS Block 1B Cargo or SLS Block 2).

As you implicitly note in mentioning SLS's TMI capabilities, NASA sees fit to break its Mars mission into chunks of less than 50 tonnes.  That begs the question of whether those chunks could be lofted in to LEO by a Falcon Heavy or equivalent and then boosted onward a cis-lunar staging point or directly to Mars after rendezvous and docking with expendable departure stages or perhaps reusable robotic transfer stages.  The latter seems particularly interesting, since the EMC architecture includes reusable transfer stages anyway.
Title: Re: SLS General Discussion Thread 2
Post by: RonM on 05/31/2016 03:18 PM
SLS (and NASA) is not in competition with SpaceX.

Except that SLS *is* in competition with SpaceX.

By law, NASA can't compete with commercially available products.

As soon as FH flies, some difficult questions will be asked, "why do we pay these insane money for SLS?"
For the moment NASA can claim FH does not have a large enough fairing...

...large enough *for what*? Can NASA point us to a funded payload which can't fit into FH's fairing?

Um, let's see, how about Orion? Of course it doesn't need a fairing, but saying that there are no funded payloads that can't fit into a FH fairing is silly. How about projected payloads needed for a Mars mission. That's a more realistic comparison.

Something as large as a lander would need 8.4 m or 10 m fairings. That will take SLS. Other components could be smaller and launched by commercial rockets. SLS will have a very low flight rate. It will take a combination of SLS and commercial rockets to assemble a Mars mission in a reasonable amount of time.
Title: Re: SLS General Discussion Thread 2
Post by: Coastal Ron on 05/31/2016 03:35 PM
How about projected payloads needed for a Mars mission. That's a more realistic comparison.

Depends on the architecture you look at.  There are some that assume an HLV will be available, and some that assume existing launchers will be used.

Quote
Something as large as a lander would need 8.4 m or 10 m fairings.

If we're going to Mars in fleets that we assemble in local space, then we might assemble landers in space too.  No need to be limited by the constraints of what can fit on one small HLV.

Quote
It will take a combination of SLS and commercial rockets to assemble a Mars mission in a reasonable amount of time.

It will take a combination of launchers, that we can agree on.  But since NASA is likely decades away from going to Mars on it's own, arguing the dimensions of the lander is premature at best.

And NASA has no idea how to land large landers on Mars anyways.  NASA technology currently maxes out at 899 kg for placing mass on Mars, which is too small for humans.  So it's going to take NASA decades to scale up that capability.

Or, if SpaceX is successful in their Mars endeavors, NASA can just buy a ride to Mars with them.  Regardless, a NASA HLV of any type won't be needed for quite a while to support trips to Mars.
Title: Re: SLS General Discussion Thread 2
Post by: RonM on 05/31/2016 03:51 PM
Or, if SpaceX is successful in their Mars endeavors, NASA can just buy a ride to Mars with them.  Regardless, a NASA HLV of any type won't be needed for quite a while to support trips to Mars.

Yes, I think the biggest problem with SLS is that we really don't need it for at least another decade, if ever, because of a lack of funding. They should have followed Obama's plan to do research for five years before deciding on a launch vehicle. Then fund a commercial heavy launch vehicle and see what SpaceX, ULA, etc. could come up with. Unfortunately, that's not what happened and we have spent billions of dollars on SLS. That wouldn't be bad if Congress had funded payloads suitable for SLS.

Maybe LockMart will talk Congress into their latest idea. That would get us to Mars orbit in a little over a decade.

http://forum.nasaspaceflight.com/index.php?topic=40324.0
Title: Re: SLS General Discussion Thread 2
Post by: Robotbeat on 05/31/2016 04:09 PM
FH does not compete with SLS - It throws much more upstairs !!!! And I think you will be waiting quite awhile for your "difficult" questions to be asked at the appropriate level for influence to happen!!
The law says that the missions should be designed to accommodate commercial vehicles. So even if SLS does throw slightly more to orbit, that does NOT mean FH doesn't compete with SLS.
Title: Re: SLS General Discussion Thread 2
Post by: Khadgars on 05/31/2016 05:07 PM
The goal post on which SLS will die has continually been moved and talked about ad nauseum.

NASA has already stated they can create the DSH and get humans to Mars under the current budget via Lockheed's Mars Base Camp or something similar to it.  Its the lander that doesn't fit into existing or foreseeable budget.

SLS does and will have payloads.  Getting to Mars is going to take SLS and commercial launchers and the whole industry pulling in the same direction.
Title: Re: SLS General Discussion Thread 2
Post by: oldAtlas_Eguy on 05/31/2016 05:16 PM
The following shows what a typical NASA program to develop hardware for a Mars mission would look like.

Authorization/Appropriations                   Oct-17
Contract for Authorization Study start           Mar-18
Architecture selected                                   Mar-19
Contract for Design and Development start   Sep-19
PDR                                                           Sep-21
CDR                                                           Sep-24
Hardware build complete                           Sep-29
Launch Earliest Mars Synod                   Feb-31

This is how slow NASA really is. The biggest problem is in program startup. It would take 3 years from now just to get a contractor on contract to start the design work.

SLS would not be used for any payloads like this until the 2030's just like NASA has been stating all along.
Title: Re: SLS General Discussion Thread 2
Post by: Khadgars on 05/31/2016 05:39 PM
The following shows what a typical NASA program to develop hardware for a Mars mission would look like.

Authorization/Appropriations                   Oct-17
Contract for Authorization Study start           Mar-18
Architecture selected                                   Mar-19
Contract for Design and Development start   Sep-19
PDR                                                           Sep-21
CDR                                                           Sep-24
Hardware build complete                           Sep-29
Launch Earliest Mars Synod                   Feb-31

This is how slow NASA really is. The biggest problem is in program startup. It would take 3 years from now just to get a contractor on contract to start the design work.

SLS would not be used for any payloads like this until the 2030's just like NASA has been stating all along.

NASA can't do Apollo like programs where all the design and production is done in parallel.  From 2018 to 2028 SLS/Orion will be in Cislunar space as its always been planned.  Saying SLS has nothing to do for the next 10 years is inaccurate.  Especially if ARM is turned into a cislunar outpost SLS/Orion will have more than enough to do.
Title: Re: SLS General Discussion Thread 2
Post by: oldAtlas_Eguy on 05/31/2016 06:26 PM
The following shows what a typical NASA program to develop hardware for a Mars mission would look like.

Authorization/Appropriations                   Oct-17
Contract for Authorization Study start           Mar-18
Architecture selected                                   Mar-19
Contract for Design and Development start   Sep-19
PDR                                                           Sep-21
CDR                                                           Sep-24
Hardware build complete                           Sep-29
Launch Earliest Mars Synod                   Feb-31

This is how slow NASA really is. The biggest problem is in program startup. It would take 3 years from now just to get a contractor on contract to start the design work.

SLS would not be used for any payloads like this until the 2030's just like NASA has been stating all along.

NASA can't do Apollo like programs where all the design and production is done in parallel.  From 2018 to 2028 SLS/Orion will be in Cislunar space as its always been planned.  Saying SLS has nothing to do for the next 10 years is inaccurate.  Especially if ARM is turned into a cislunar outpost SLS/Orion will have more than enough to do.
The discussion was about Mars payloads. SLS does have some in the work payloads besides Orion and that is DSH which hopefully would be mid 2020's.

Added: I see the DSH program launching a DSH NET Dec 2023. The program length is shorter than for a Mars program because of less complexity and that the architecture studies have been completed and NASA is moving on to a DDT&E contractor selection that would probably begin in FY2017. DSH is already 3 years ahead of any other "new" SLS payload program. Then there is the 2 Europa probes missions which are well on their way into the home stretch. So there are 3 payloads for 2020's that is not an Orion. EM-2 is NET 2022. But engine build rates and engine availability are such that flights would only be possible for 2023 (1st Europa), 2024 DSH/Orion, 2026 second Europa, 2027 another Orion, and 2029 a possible another DSH/Orion. And that is probably pushing the SLS hardware availabilities. 6 flights for all of the 2020's if we are lucky.
Title: Re: SLS General Discussion Thread 2
Post by: Jim on 05/31/2016 06:35 PM
that is DSH which hopefully would be mid 2020's.

DSH is just a study, it is not an approved project.  The only payloads that are real for SLS at this moment are Orion based and are EM-1 and ARRM.  Europa is the next closest.
Title: Re: SLS General Discussion Thread 2
Post by: oldAtlas_Eguy on 05/31/2016 06:50 PM
that is DSH which hopefully would be mid 2020's.

DSH is just a study, it is not an approved project.  The only payloads that are real for SLS at this moment are Orion based and are EM-1 and ARRM.  Europa is the next closest.
As I have added above they are finishing up funded architecture studies. My notes as you have pointed out are optimistic. There is more funding in the 2017 budget for DSH, hopefuly a development start. But even a 1 year delay is not a bad thing in that SLS hardware availability for launching a DSH may not exist until 2025 anyway. The other item is funding in 2017 for ARRM is 0. As far the Europa missions they are having funding problems of their own and may be delayed as well.
Title: Re: SLS General Discussion Thread 2
Post by: Coastal Ron on 05/31/2016 09:37 PM
The goal post on which SLS will die has continually been moved and talked about ad nauseum.

Yep.  Mainly because we thought Congress would finally get around to talking about what the SLS was supposed to be used for, which would involve discovering how much money using the SLS would require.  That never happened, since Congress as a whole is just not interested in discussing uses for the SLS.  So Plan B is that the next President will create a review of the program, which will push for some sort of decision to be made, one way other the other.

Quote
NASA has already stated they can create the DSH and get humans to Mars under the current budget via Lockheed's Mars Base Camp or something similar to it.  Its the lander that doesn't fit into existing or foreseeable budget.

There has been testimony in front of Congress from two very respected people, Thomas Young (former VP of Lockheed Martin) and Steven Squyres (Principle Investigator of the Mars Exploration Rover mission), in which Young was asked how long it would take NASA to put a human on Mars with it's current budget, and Young said "Never."  Squyres agreed.

And I have no doubt that NASA can do anything asked of it, IF it is given enough money.  But our nation's politicians haven't asked NASA to go to Mars yet, nor provided the required money.  Yet.

Quote
SLS does and will have payloads.

The year the Shuttle first launched (1981), there was a backlog of over 40 payloads waiting to fly on it.  For that point in history, that certainly showed that it's services were needed.

In comparison, outside of test flights, the SLS manifest is pretty bare.  That's not a good sign.

Quote
Getting to Mars is going to take SLS and commercial launchers and the whole industry pulling in the same direction.

All of which has to come out of NASA's budget, since we're talking about a government-only initiative.  That will require a heck of a budget boost.  Just sayin'...
Title: Re: SLS General Discussion Thread 2
Post by: Khadgars on 05/31/2016 11:23 PM
Points well taken.

When I refer to current budget, I'm referencing the entire HSF budget which is around $9 billion per year.

With $9billion per year, particularly after 2024 when ISS comes down, NASA can get to Mars.
Title: Re: SLS General Discussion Thread 2
Post by: TomH on 06/01/2016 03:33 AM
With $9billion per year, particularly after 2024 when ISS comes down, NASA can get to Mars.

If they're buying a ride from SpaceX, then yea. If you expect it to be via SLS/Orion, I wouldn't bet anything of value on that horse.
Title: Re: SLS General Discussion Thread 2
Post by: Khadgars on 06/01/2016 05:25 AM
With $9billion per year, particularly after 2024 when ISS comes down, NASA can get to Mars.

If they're buying a ride from SpaceX, then yea. If you expect it to be via SLS/Orion, I wouldn't bet anything of value on that horse.

We can agree to disagree  ;)
Title: Re: SLS General Discussion Thread 2
Post by: envy887 on 06/11/2016 05:55 PM
$9billion per year, particularly after 2024 when ISS comes down, NASA can get to Mars.
9B a year and the first manned landing happens when? 2034? And how many billions will they spend from now till 2024?

You're talking about 100+ billion to be spent on this program over 18 years before a manned landing, for the capability to land maybe 100 tonnes of payload per synod. With hardware that isn't even on the drawing board yet.

Those are great ambitions, but I have no faith in them. For that kind of money SpaceX could land 10 times the payload annually, starting in 3 years.
Title: Re: SLS General Discussion Thread 2
Post by: Coastal Ron on 06/11/2016 06:16 PM
Points well taken.

When I refer to current budget, I'm referencing the entire HSF budget which is around $9 billion per year.

With $9billion per year, particularly after 2024 when ISS comes down, NASA can get to Mars.

According to NASA, the SLS has to launch no-less-than once every 12 months in order to have a safe launch cadence.  So that means that within NASA's budget they have to support:

- Building Orion systems for HSF training flights

- Science missions that make use of the SLS (i.e. the Europa mission)

- Development and testing of HSF mission elements like the DSH Hab

- Production of SLS rockets to support flights every year

- Support costs for ongoing missions that are launched via SLS

I just don't see that fitting into NASA's current budget profile, especially the yearly SLS flights.  Not only that, the amount of time it takes to build SLS-sized science payloads and HSF systems does not lend itself to popping out at yearly intervals - some will take a decade or more to get ready, as the history of the simple Orion spacecraft shows (i.e. 18 years).

And we are still missing an explicit political goal for our HSF efforts beyond LEO, which makes long-term efforts less likely to succeed.

Just sayin'...
Title: Re: SLS General Discussion Thread 2
Post by: PahTo on 06/11/2016 06:17 PM
With hardware that isn't even on the drawing board yet.

Those are great ambitions, but I have no faith in them. For that kind of money SpaceX could land 10 times the payload annually, starting in 3 years.

With all due respect, dare I say some of the necessary "hardware" is being flight tested on ISS as we type...
Title: Re: SLS General Discussion Thread 2
Post by: edkyle99 on 06/11/2016 06:39 PM
I propose that we ban the word "SpaceX", and any message using that word or any description of any existing or proposed system proposed by that company, from this thread, which is titled "SLS General Discussion".   There are about 10,000 other threads for SpaceX, and multiple forum subsections.  There is only one SLS section, and it is constantly overrun by messages claiming that SpaceX can do these NASA missions for one-tenth the price in one-third the time, etc..  These claims seem widely optimistic to anyone who has been immersed in this business for any length of time.  But who knows, maybe they'll magically turn out to be true!  Either way, discussion of them does not belong here.  Please.

 - Ed Kyle
Title: Re: SLS General Discussion Thread 2
Post by: rcoppola on 06/11/2016 07:12 PM
Once 5 Seg, Core and EUS are out of development, testing and into production...and once 39B, MLT, CT and VAB are completed along with GSDO software, updated LCC...assuming 1 (maybe 2) flights a year, what could we expect the minimum cost per flight to be? In total, will it be 300, 600, 800 Million? What could we realistically expect a line item of one flight, either Cargo or Orion to cost over time? (not including Orion or cargo, fairing.)

Could we get this system to, say...250 Million per launch?

IMO, the greatest potential for this beast is throw weight of BEO science and colonization infrastructure, not people.
Title: Re: SLS General Discussion Thread 2
Post by: envy887 on 06/11/2016 07:31 PM
Discussion of the SLS budget doesn't belong in the SpaceX threads (although that happens too). And why shouldn't SLS general discussion include comparison to it's competitors? Don't tell me that there are no competitors. SLS is a transport service. It doesn't have any "missions", other than to deliver a payload. That's not NASA's forte, and there are thousands of other things they are awesome at that they should be spending the money on. And that's not a dig at NASA, but at Congress.
Title: Re: SLS General Discussion Thread 2
Post by: rayleighscatter on 06/11/2016 09:13 PM
And why shouldn't SLS general discussion include comparison to it's competitors?
Because we have other forums to discuss its competitors and Congress. Moderators have been pretty clear on this point in the past.
Title: Re: SLS General Discussion Thread 2
Post by: Proponent on 06/11/2016 11:24 PM
Once 5 Seg, Core and EUS are out of development, testing and into production...and once 39B, MLT, CT and VAB are completed along with GSDO software, updated LCC...assuming 1 (maybe 2) flights a year, what could we expect the minimum cost per flight to be? In total, will it be 300, 600, 800 Million? What could we realistically expect a line item of one flight, either Cargo or Orion to cost over time? (not including Orion or cargo, fairing.)

Could we get this system to, say...250 Million per launch?

To my knowledge, the closest we've seen to actual cost estimates are the numbers in the ESD budget scenarios from 2011 (https://forum.nasaspaceflight.com/index.php?topic=26709.msg804592#msg804592).  They seem to suggest a cost of about $3 billion for one Block 2* SLS launch annually, including ground systems and estimated inflation to FY 2025.  Launching one Block 1 and one Block 2 appeared to cost about $3.6 billion.  SLS's costs do not seem set to go down when it moves from development to operation.  NASA as bandied about a number of $500 million per launch:  it would seem that could only be the marginal cost of an additional annual launch, not the total annual cost per launch.



* Bear in mind that the blocks were not then defined precisely as we know them now.
Title: Re: SLS General Discussion Thread 2
Post by: Khadgars on 06/12/2016 03:15 AM
Once 5 Seg, Core and EUS are out of development, testing and into production...and once 39B, MLT, CT and VAB are completed along with GSDO software, updated LCC...assuming 1 (maybe 2) flights a year, what could we expect the minimum cost per flight to be? In total, will it be 300, 600, 800 Million? What could we realistically expect a line item of one flight, either Cargo or Orion to cost over time? (not including Orion or cargo, fairing.)

Could we get this system to, say...250 Million per launch?

To my knowledge, the closest we've seen to actual cost estimates are the numbers in the ESD budget scenarios from 2011 (https://forum.nasaspaceflight.com/index.php?topic=26709.msg804592#msg804592).  They seem to suggest a cost of about $3 billion for one Block 2* SLS launch annually, including ground systems and estimated inflation to FY 2025.  Launching one Block 1 and one Block 2 appeared to cost about $3.6 billion.  SLS's costs do not seem set to go down when it moves from development to operation.  NASA as bandied about a number of $500 million per launch:  it would seem that could only be the marginal cost of an additional annual launch, not the total annual cost per launch.



* Bear in mind that the blocks were not then defined precisely as we know them now.

Lets say for instance, that your figure of $3.6 billion for 2 sls launches is correct in 2025.

$3.6 billion for SLS
$1 billion for Orion
$3.4 billion for DSH/MTV (BA330/Cygnus, ELCS, etc)
$1 billion commercial (spacex, Boeing, etc)

With no ISS, NASA's budget will work imo
Title: Re: SLS General Discussion Thread 2
Post by: MikeAtkinson on 06/12/2016 06:02 AM
Giving up a large and still expanding LEO presence for the occasional BEO mission is not a good trade in my opinion.
Title: Re: SLS General Discussion Thread 2
Post by: Coastal Ron on 06/12/2016 03:14 PM
Could we get this system to, say...250 Million per launch?

No, that would be impossible.

Consider that back when the Shuttle was flying prior to the Columbia accident, and NASA was assuming a robust flight schedule, NASA had negotiated contracts for volume production of the External Tank (ET) and the Solid Rocket Motors (SRM).  At that point in time a Shuttle flight set of ET & SRM's cost $242M.

The SLS uses larger SRM's, and the 1st stage body of the SLS is far larger and more complex than the Shuttle ET.  So just from that standpoint, based on the low flight rate currently envisioned, the SLS could never cost only $250M per launch.

Plus the "SLS" includes the upper stage, since the job of the SLS is to transport it's payload to it's ultimate destination, so upper stage costs have to be added too.

Another cost comparison is ULA's Delta IV Heavy, which is in volume production due to it being composed of three Delta IV CBC's (and Delta IV-M is in production).  The cost to the U.S. Government is somewhere north of $500M these days, which though that includes some payloads specific considerations, still provides a rough order of magnitude comparison - and the Delta IV Heavy is far smaller than the SLS.

Quote
IMO, the greatest potential for this beast is throw weight of BEO science and colonization infrastructure, not people.

Science missions are the least defensible uses for the SLS, since "when we need science" is open to interpretation - all the way from "now" to "later".  And once one or more of the U.S. launch providers offers some version of multi-launch support, the U.S. Government won't be able to compete against the private sector for those launches.

Only Human Space Flight (HSF) using NASA specific in-space elements justify the need for the SLS.  And then only if there is enough of it over the long term.  We'll see if Congress wants to fund that type of stuff at this moment in history...
Title: Re: SLS General Discussion Thread 2
Post by: Khadgars on 06/13/2016 06:46 PM
Giving up a large and still expanding LEO presence for the occasional BEO mission is not a good trade in my opinion.

NASA won't be giving anything up, as there is no international support past 2024 to keep ISS going making your point moot.

Title: Re: SLS General Discussion Thread 2
Post by: Robotbeat on 06/13/2016 07:09 PM
Giving up a large and still expanding LEO presence for the occasional BEO mission is not a good trade in my opinion.

NASA won't be giving anything up, as there is no international support past 2024 to keep ISS going making your point moot.
NASA has repeatedly said it wants LEO research capability beyond 2024.
Title: Re: SLS General Discussion Thread 2
Post by: Khadgars on 06/13/2016 07:25 PM
Giving up a large and still expanding LEO presence for the occasional BEO mission is not a good trade in my opinion.

NASA won't be giving anything up, as there is no international support past 2024 to keep ISS going making your point moot.
NASA has repeatedly said it wants LEO research capability beyond 2024.

Not via ISS.  My whole point is, once ISS comes down NASA's budget can make Mars missions work.

Title: Re: SLS General Discussion Thread 2
Post by: Kansan52 on 06/13/2016 07:29 PM
The vehicle doesn't matter. The mission matters. Congress has forgotten that. Give NASA a mission and allow them to work it. Might be SLS, might be something else. But whatever mission is selected, NASA needs to be funded enough to accomplish the mission. IMHO NASA does not have enough funding to do every task that has been mandated by Congress.
Title: Re: SLS General Discussion Thread 2
Post by: PahTo on 06/13/2016 07:41 PM

Thanks AnalogMan.  For anyone:  will they be able to use this adapter between the EUS and 5 meter payloads (ostensibly Orion+SM) when that variant flies?
Title: Re: SLS General Discussion Thread 2
Post by: whitelancer64 on 06/13/2016 08:01 PM

Thanks AnalogMan.  For anyone:  will they be able to use this adapter between the EUS and 5 meter payloads (ostensibly Orion+SM) when that variant flies?

No. This adapter will be used only one time, for the SLS flight with the Interim Cryogenic Propulsion Stage. A shorter "Universal Stage Adapter" will be made for the EUS / Orion.
Title: Re: SLS General Discussion Thread 2
Post by: psloss on 06/28/2016 01:10 AM
We got to see one of the center segments for EM-1 already made at the NASA Social today. Don't know if it's for left or right hand booster. Again this is SLS flight hardware, the 1st segment that came through the final assembly building.
Nice -- was this picture via Orbital ATK?  They told us no pictures on our tour, but we could request photo subjects that would then get a safety check for things like ITAR.  The only other detail I heard when we went through Final Assembly was that it was a forward-center segment.
Title: Re: SLS General Discussion Thread 2
Post by: Chris Bergin on 06/28/2016 01:36 AM
We got to see one of the center segments for EM-1 already made at the NASA Social today. Don't know if it's for left or right hand booster. Again this is SLS flight hardware, the 1st segment that came through the final assembly building.
Nice -- was this picture via Orbital ATK?  They told us no pictures on our tour, but we could request photo subjects that would then get a safety check for things like ITAR.  The only other detail I heard when we went through Final Assembly was that it was a forward-center segment.


They were tweeting various photos, not sure about that one.

https://twitter.com/OrbitalATK
Title: Re: SLS General Discussion Thread 2
Post by: Bubbinski on 06/29/2016 01:18 AM
We were allowed to take pics in the final assembly building. We all got excited when we heard that and took some pics. We weren't allowed to take pics anywhere else on our tour. That pic was mine, I only wish I'd thought to bring my Coolpix in instead of my iPad camera which I used.
Title: Re: SLS General Discussion Thread 2
Post by: Endeavour_01 on 06/29/2016 09:32 PM
We were allowed to take pics in the final assembly building. We all got excited when we heard that and took some pics. We weren't allowed to take pics anywhere else on our tour. That pic was mine, I only wish I'd thought to bring my Coolpix in instead of my iPad camera which I used.

Great pic Bubbinski. It is so good to see actual flight hardware coming down the pipe. Can't wait to see this bird fly.  :D
Title: Re: SLS General Discussion Thread 2
Post by: psloss on 07/08/2016 01:55 PM
We got to see one of the center segments for EM-1 already made at the NASA Social today. Don't know if it's for left or right hand booster. Again this is SLS flight hardware, the 1st segment that came through the final assembly building.
Nice -- was this picture via Orbital ATK?  They told us no pictures on our tour, but we could request photo subjects that would then get a safety check for things like ITAR.  The only other detail I heard when we went through Final Assembly was that it was a forward-center segment.
Orbital ATK posted images that they captured during the media tour on Flickr; there are a couple of images of the EM-1 segment in the album:
https://www.flickr.com/photos/orbital-atk/sets/72157670004069052
Title: Re: SLS General Discussion Thread 2
Post by: WindyCity on 07/23/2016 12:52 AM
Bob Zimmerman (aerospace historian and award-winning author of Leaving Earth: Space Stations, Rival Superpowers, and the Quest for Interplanetary Travel) has prepared a study for the think tank Center for A New American Security to be released in August that takes a critical look at NASA's two-pronged strategy for human space flight involving SLS/Orion and commercial space. In a fascinating two-hour Space Show interview, he previews many of his conclusions. Go to http://www.thespaceshow.com/show/28-jun-2016/broadcast-2728-bob-zimmerman to listen to the interview.

In brief, he takes a highly negative view of the SLS/Orion program because of its high costs, legacy architecture, long R&D timeline, low launch cadence, and mission objectives. Listening to the interview was well worth my time. He praises the work being done by SpaceX, Blue Origin, and Bigelow Aerospace.
Title: Re: SLS General Discussion Thread 2
Post by: Oli on 07/23/2016 09:30 PM
In brief, he takes a highly negative view of the SLS/Orion program because of its high costs, legacy architecture, long R&D timeline, low launch cadence, and mission objectives. Listening to the interview was well worth my time. He praises the work being done by SpaceX, Blue Origin, and Bigelow Aerospace.

He makes his arguments in the first 5 minutes, the rest is not particularly interesting. IMO he puts to much emphasis on "commercial is so much more awesome" instead of the fact that SLS/Orion has nowhere to fly to.

I was recently thinking about how to make SLS into an effective LEO launcher, since SEP will eat away the benefit of SLS's high BEO capacity. The problem is that in such a case even less SLS launches will be needed (EMC can already be done with 2 SLS per year without using SEP for LEO to LDRO).

If Orbital/ATK gets its all-solid rocket maybe the monster can be slayed?

Sorry if OT.
Title: Re: SLS General Discussion Thread 2
Post by: Chalmer on 08/03/2016 08:42 PM
So I have been wondering for awhile now about the RS-25 testing.

I mean what are they testing? Shouldn't the RS-25 be very well understood with all that test and flight history from shuttle?

As best as I can surmise from the #Journeytomars PR press releases there is an upgraded controller and it will use 109% thrust and not 104.5% thrust as under shuttle.

Is that it?
Title: Re: SLS General Discussion Thread 2
Post by: Khadgars on 08/03/2016 09:04 PM
So I have been wondering for awhile now about the RS-25 testing.

I mean what are they testing? Shouldn't the RS-25 be very well understood with all that test and flight history from shuttle?

As best as I can surmise from the #Journeytomars PR press releases there is an upgraded controller and it will use 109% thrust and not 104.5% thrust as under shuttle.

Is that it?

From NASA's website;

Quote
The July 29 test and four future scheduled firings in the current series are focused on the new engine controller and higher operating parameters. While RS-25 engines are among the most tested – and proven – in the world, they have been modernized for SLS. The developmental tests are designed to show they will meet the new parameters of the rocket. During the firings, the test team will put the engine through a variety of adaptations, starting it at different temperatures and pressures, for instance. The team also will watch closely to ensure the new engine controller functions as needed. In addition to the existing RS-25 engines, NASA has contracted with Aerojet Rocketdyne to build additional engines for use on SLS missions. All flight testing for SLS take place at Stennis, as will the actual core stage testing for the first integrated mission of SLS and NASA’s Orion spacecraft, Exploration Mission-1. The next scheduled RS-25 developmental test at Stennis is set for Aug. 18.

Testing is always a good thing.
Title: Re: SLS General Discussion Thread 2
Post by: redliox on 08/03/2016 09:25 PM
In brief, he takes a highly negative view of the SLS/Orion program because of its high costs, legacy architecture, long R&D timeline, low launch cadence, and mission objectives. Listening to the interview was well worth my time. He praises the work being done by SpaceX, Blue Origin, and Bigelow Aerospace.

He makes his arguments in the first 5 minutes, the rest is not particularly interesting. IMO he puts to much emphasis on "commercial is so much more awesome" instead of the fact that SLS/Orion has nowhere to fly to.

I was recently thinking about how to make SLS into an effective LEO launcher, since SEP will eat away the benefit of SLS's high BEO capacity. The problem is that in such a case even less SLS launches will be needed (EMC can already be done with 2 SLS per year without using SEP for LEO to LDRO).

If Orbital/ATK gets its all-solid rocket maybe the monster can be slayed?

Sorry if OT.

I don't see the SLS as a monster, but the Orion atop it could be an annoying goblin.

The SLS itself was produced as the best compromise available based on the Augustine Commission's demands, as best they could be interpreted at the time.  So I find it a bad comedy when people complain about it now.  The space shuttle's reuseability was seen as an expensive liability, so it was cut out; and ironically people nowadays complain it's not reusable like the Falcon 9 first stage.  They thought basing it off mainly shuttle components would save the workforce, whereas now they complain it's old tech.  For crying out loud people!

I'd say slay the Orion, keep the SLS, and use commercial flights.  I could see the SLS easily flying an empty Mars or Lunar lander into LEO and whatever equipment, and then a smaller commercial launcher deliver the humans separately.  That would be the best compromise to me.
Title: Re: SLS General Discussion Thread 2
Post by: Proponent on 08/03/2016 09:30 PM
Augustine did not demand an SLS-sized heavy lifter.  It offered the possibility of using a rocket with a capacity of 50-ish tonnes to LEO, possibly commercially managed.

In any event, regardless of launch vehicle, Augustine said that NASA needed an extra $3 billion per year (which would be more now) if it were to do much of anything.
Title: Re: SLS General Discussion Thread 2
Post by: Kansan52 on 08/03/2016 10:42 PM
It's be a while since reading the report, but memory says there was a chart that said the only mores expensive (as a launch system) then Ares I/Orion was anything else/Orion (which is the result we have exists now).

Has memory skewed that or was that a basic observation in the report?
Title: Re: SLS General Discussion Thread 2
Post by: Zed_Noir on 08/06/2016 08:26 AM
We got a FISO presentation titled "NASA's Space Launch System: Powering the Journey to Mars" by Chris Saunders (AJ), Mike Fuller (Orb-ATK), & Bob DaLee (Boeing) on August 3. Links to the audio & slide presentations below.

Slides link (http://spirit.as.utexas.edu/~fiso/telecon/Sanders-Fuller-DaLee_8-3-16/Sanders-Fuller-DaLee_8-3-16.pdf)

Audio link (http://spirit.as.utexas.edu/~fiso/telecon/Sanders-Fuller-DaLee_8-3-16/Sanders-Fuller-DaLee.mp3)


Slide of the various SLS variants and slide of various launch vehicles with  performance charts to various orbits from the slide presentations.
Title: Re: SLS General Discussion Thread 2
Post by: Khadgars on 08/06/2016 03:39 PM
Thank you for the links.  I like seeing EM-2 at 2021  ;D
Title: Re: SLS General Discussion Thread 2
Post by: oldAtlas_Eguy on 08/06/2016 04:09 PM
An excellently done presentation. The one item conspicuously missing is costs. If you add the $/mt for the different orbits for each vehicle the story changes significantly as to the advantages and disadvantages for the LVs depicted.

But otherwise the relative capabilities chart is an excellent reference item.

Added:
Estimate of what the cost data would look like.
Cost/flt ($M)LEO GEO Lunar Mars
VehiclePayload (mt)Cost/mt ($M)Payload (mt)Cost/mt ($M)Payload (mt)Cost/mt ($M)Payload (mt)Cost/mt ($M)
Atlas V$22418.8$11.98.9$25.28.9$25.26$37.3
F9$6222.8$2.78.3$7.58.3$7.54.02$15.4
DIVH$45028.37$15.913.81$32.613.81$32.610$45
FH$13054.4$2.422.2$5.919.8$6.613.6$9.6
SLS 1B$1000105$9.542.5$23.538$26.330$33.3
SLS 2B$800130$6.262$12.946$17.442.5$18.8
Vulcan$18033$5.515.6$11.515.6$11.510.5$17.1
Vulcan Distributed Launch$340$33$10.333$10.333$10.3

I used a lower per flt cost for SLS 2B in the hope that the cost per flt would go down with more use.

Edit #2: I decided to add Vulcan with ACES to the table just to see where it lies in the comparisons on $M/mt.
Title: Re: SLS General Discussion Thread 2
Post by: Robotbeat on 08/06/2016 09:14 PM
how the heck are they going to test a 10m diameter fairing? Where? Or even an 8.4m fairing?
Title: Re: SLS General Discussion Thread 2
Post by: Zed_Noir on 08/06/2016 09:35 PM
...
I used a lower per flt cost for SLS 2B in the hope that the cost per flt would go down with more use.
That is wishful thinking. Expect the SLS 2B to be more expensive than the SLS 1B, IMO. Also to get to the SLS 2B you need to restart RS-25 production and developed some flavor of advance booster. The advance booster is iffy considering the past with the STS's booster history.

And your table shows how noncompetitive the SLS is for assembling vehicle stacks in LEO in price. Of course the SLS will have a bigger payload fairing.
Title: Re: SLS General Discussion Thread 2
Post by: oldAtlas_Eguy on 08/06/2016 09:54 PM
...
I used a lower per flt cost for SLS 2B in the hope that the cost per flt would go down with more use.
That is wishful thinking. Expect the SLS 2B to be more expensive than the SLS 1B, IMO. Also to get to the SLS 2B you need to restart RS-25 production and developed some flavor of advance booster. The advance booster is iffy considering the past with the STS's booster history.

And your table shows how noncompetitive the SLS is for assembling vehicle stacks in LEO in price. Of course the SLS will have a bigger payload fairing.
You are correct in that historically NASA costs have increased as the LV capability was expanded. But there is always hope that they would also do cost reduction work at the same time as creating a new version.

In the end LV selection could be just payload faring volume, cost being a secondary consideration. Bulky items SLS. Compact items commercial, such as propellant stages.
Title: Re: SLS General Discussion Thread 2
Post by: whitelancer64 on 08/06/2016 09:54 PM
how the heck are they going to test a 10m diameter fairing? Where? Or even an 8.4m fairing?

At the Space Power Facility in Plum Brook Station, Ohio. The largest vacuum chamber there is 30 meters in diameter and 37 meters tall.
Title: Re: SLS General Discussion Thread 2
Post by: Zed_Noir on 08/06/2016 09:57 PM
how the heck are they going to test a 10m diameter fairing? Where? Or even an 8.4m fairing?

 :)
Live test on a commercial launcher with an adapter. After all the Atlas V got that 7.2 meter fairing option.
 :)
Title: Re: SLS General Discussion Thread 2
Post by: A_M_Swallow on 08/06/2016 11:42 PM
how the heck are they going to test a 10m diameter fairing? Where? Or even an 8.4m fairing?

 :)
Live test on a commercial launcher with an adapter. After all the Atlas V got that 7.2 meter fairing option.
 :)

In which case I hope the dummy payload comes with telemetry so the engineers any problems the fairing has opening.
Title: Re: SLS General Discussion Thread 2
Post by: PahTo on 08/07/2016 02:18 AM

I guess its once again time for my quarterly reminder that should SLS fly, or fly more than a couple-four times, the ultimate variation we'll see is 1B.  Having said that, I fully support SLS, and I bet the refined 1B will throw N. of 111T.


Title: Re: SLS General Discussion Thread 2
Post by: Space Ghost 1962 on 08/07/2016 03:38 AM
how the heck are they going to test a 10m diameter fairing? Where? Or even an 8.4m fairing?
(https://cdn.meme.am/instances/500x/68572158.jpg)

"You don't understand the power of the dark ... wait ... cost plus prime force ..." ;)

And that one won't come cheap. Also, the Skylab one didn't "fair" so well...

add:
(https://www.nasa.gov/sites/default/files/thumbnails/image/gpn-2000-001462.jpg)
and
(https://mix.msfc.nasa.gov/IMAGES/HIGH/0101587.jpg)

6.6m x 17.1m
Title: Re: SLS General Discussion Thread 2
Post by: Robotbeat on 08/07/2016 04:02 AM
how the heck are they going to test a 10m diameter fairing? Where? Or even an 8.4m fairing?

At the Space Power Facility in Plum Brook Station, Ohio. The largest vacuum chamber there is 30 meters in diameter and 37 meters tall.
Oh, I know Plum Brook well. I've been inside it before. But even testing the 5m commercial fairings is cramped, let alone a much taller and wider 10m fairing. I'd argue there isn't enough room for a 10m by 30m fairing to be fully tested inside the space, since it needs room to actually separate, with all the mechanisms involved.

Heck, the doors are only 15m square. I don't see it realistically and fully being tested at Plum Brook, and I've never seen this realistically addressed.

10m fairings are a nightmare and likely to cost a fortune. How do you even transport them? Build them? Test them?

8.4m fairing even is a stretch (though isn't as absurd as 10m). My bet is SLS will fly only with Orion or the 5m fairing before being cancelled.
Title: Re: SLS General Discussion Thread 2
Post by: Coastal Ron on 08/07/2016 06:15 AM
Fiso podcast on SLS.

http://spirit.as.utexas.edu/~fiso/telecon/Sanders-Fuller-DaLee_8-3-16/

Costs aside there is lot to be said for being able to deliver 45t and 10m dia payloads direct to Mars , plus greatly reduce travel time for outer solar system robotic missions.

Well of course if you ignore costs every capability looks great.  Unfortunately there IS a cost associated with each capability, and that will influence whether that capability is ever used.
Title: Re: SLS General Discussion Thread 2
Post by: Zed_Noir on 08/07/2016 08:41 AM

I guess its once again time for my quarterly reminder that should SLS fly, or fly more than a couple-four times, the ultimate variation we'll see is 1B.  Having said that, I fully support SLS, and I bet the refined 1B will throw N. of 111T.
@Scotty disagree with you on the Clarification on SLS Block 1B Capabilities thread (http://forum.nasaspaceflight.com/index.php?topic=39526.msg1488720#msg1488720) on the 111T+ guess. Presuming you meant metric tons.
Title: Re: SLS General Discussion Thread 2
Post by: Oli on 08/07/2016 01:46 PM
I'd say slay the Orion, keep the SLS, and use commercial flights.  I could see the SLS easily flying an empty Mars or Lunar lander into LEO and whatever equipment, and then a smaller commercial launcher deliver the humans separately.  That would be the best compromise to me.

Orion won't come with the same fixed costs as SLS. Sure, given Orion's development cost I would say adding a hab/prop module to a commercial crew vehicle would have been the cheaper solution (or even a lunar taxi with propulsive capture).

With SLS you're looking at >$2bn per year for 2 launches. Starting at the end of the next decade. Until it flies at that rate it is going to cost another ~$20bn. All that while FH comes "for free" and SEP costs a fraction and is needed anyway.
Title: Re: SLS General Discussion Thread 2
Post by: tea monster on 08/07/2016 02:05 PM
If they actually use the SLS on this 'Journey to Mars' and launch a load of new robot spacecraft to the outer solar system on high-speed trajectories, then brilliant.

The problem is that nobody believes that will happen. There has been little, if any interest in putting something on top of this rocket, as if everyone knows what is going to happen.
Title: Re: SLS General Discussion Thread 2
Post by: the_other_Doug on 08/07/2016 02:07 PM
With SLS you're looking at >$2bn per year for 2 launches. Starting at the end of the next decade. Until it flies at that rate it is going to cost another ~$20bn. All that while FH comes "for free" and SEP costs a fraction and is needed anyway.

As opposed (adjusting to match projected timeframe dollars for SLS) to flying eight FH's for $2bn per year?  Or four Delta IV's?  Or three Vulcans?

And how in the world do you figure that FH comes "for free"?!  FH right now is being guesstimated at a cost per launch between $120 million and $250 million, depending on who you listen to.  Delta IV is already around a half billion per launch, Atlas V at around a quarter to a third of a billion, and I don't know anyone who is willing to bet that Vulcan will cost less than either of the other two ULA offerings available at present.

This is, pardon me for saying so, one of the stupidest examples of going way overboard on "SLS will cost so much, it's completely absurd!"  By trying to state that FH is "for free," you completely invalidate any argument you may have.

Face it -- there ain't no big launchers that aren't relatively expensive right now.  The difference between SpaceX and other providers is simply a matter of degree, at the moment.
Title: Re: SLS General Discussion Thread 2
Post by: Oli on 08/07/2016 02:37 PM
With SLS you're looking at >$2bn per year for 2 launches. Starting at the end of the next decade. Until it flies at that rate it is going to cost another ~$20bn. All that while FH comes "for free" and SEP costs a fraction and is needed anyway.

As opposed (adjusting to match projected timeframe dollars for SLS) to flying eight FH's for $2bn per year?  Or four Delta IV's?  Or three Vulcans?

And how in the world do you figure that FH comes "for free"?!  FH right now is being guesstimated at a cost per launch between $120 million and $250 million, depending on who you listen to.  Delta IV is already around a half billion per launch, Atlas V at around a quarter to a third of a billion, and I don't know anyone who is willing to bet that Vulcan will cost less than either of the other two ULA offerings available at present.

This is, pardon me for saying so, one of the stupidest examples of going way overboard on "SLS will cost so much, it's completely absurd!"  By trying to state that FH is "for free," you completely invalidate any argument you may have.

Face it -- there ain't no big launchers that aren't relatively expensive right now.  The difference between SpaceX and other providers is simply a matter of degree, at the moment.

"For free" in this context means NASA doesn't have to pay for development or all the fixed cost. It is a rocket that will fly no matter what. I think FH plus SEP could approximately half the price per kg to cis-lunar space compared to SLS (assuming $200m for FH). Moreover it could save billions of development cost.

That said, I am not a die-hard SLS opponent. Congress wants to pay for it, so be it.
Title: Re: SLS General Discussion Thread 2
Post by: the_other_Doug on 08/07/2016 03:23 PM
I keep getting irritated by the oft-repeated rubric that NASA is wasting money by developing a rocket that has no funded missions in the offing.

Development of a launch capability is never done (with the exception of during Apollo, and even then was not initiated by a funded mission) because a series of funded flights require that capability.  You need to have the capability in place before you can start to fund the missions that will take advantage of it -- again, unless you want to repeat the heady go-for-broke days of Apollo.

Just as a reminder, the F-1 engine originally went into development in 1955, based upon a perceived need by the Air Force to eventually be able to orbit large payloads.

Nineteen-fifty-five.  Two years before anyone, anywhere had even demonstrated the capability of orbiting anything.  At all.

If there was a funded mission that required an F-1 engine in 1955, I'd love to see the funding appropriation for it.

And, to be honest, I don't believe it would have been possible to seek funding for Apollo if there was not an F-1 class engine already under development.  If the U.S. had been forced to try and design Apollo without the F-1 having been under development for five years already, I don't think anyone would have bitten the bullet and committed to it.  One of the reasons Apollo was considered within the realm of possibility in 1961 was the fact that the F-1 engine was scheduled to become available by 1965 or so.

Again, unless you're running a crash program like Apollo, you don't start funding your missions until the rocket needed is designed and nearly ready to go.  And I will remind y'all that, in 1966, the only Apollo crewed missions that were specifically funded were AS-204 and AS-276.  All other Apollo missions funded in that time period were unmanned tests of the vehicles. 

While the only crewed mission to fly on SLS currently funded is EM-2, at a similar point in Apollo (which was a crash program in which all elements were being designed and built all at once) there was no funding specific to any crewed Saturn V launches, much less for actual lunar landing missions.  They weren't going to happen in the next fiscal year, and as such none of the funding was specific to any such missions.

In the case of SLS/Orion, I will also point out that two of the major elements of future crewed BLEO missions -- SLS and Orion -- are in development at the same time, and targeted to come online at the same time.  And there is funding now, this year, for early stages of DSH development.  So, it's not even as if we're building a rocket that has no crewed elements under development.

When y'all toss around the complaint "no funded missions," please recall Congress only funds things one fiscal year at a time (when they bother to do so at all and we don't just get stuck with a mess of CR's).  Apollo didn't have funded crewed lunar landing missions until fiscal 1969.  NASA had a longer-than-one-year plan for Apollo, and Congress appropriated for the new fiscal year based on what NASA told them were their needs to accomplish that plan.  That doesn't differ from what's happening right now, as NASA refines their DRA for Mars and presents funding requests based on accomplishing it without many "balloon" years needed to do so (i.e., with mostly flat budgets).  Congress has given them funding for the pieces they think they need to develop in the next fiscal year.

Now, you can complain that the DRA doesn't realistically define needs for new start funding on various vehicles and preliminary missions.  But that's a far different discussion than just continuing to insist SLS must die because there are no funded missions.

Rant mode off... ;)
Title: Re: SLS General Discussion Thread 2
Post by: A_M_Swallow on 08/07/2016 05:19 PM
how the heck are they going to test a 10m diameter fairing? Where? Or even an 8.4m fairing?

At the Space Power Facility in Plum Brook Station, Ohio. The largest vacuum chamber there is 30 meters in diameter and 37 meters tall.
Oh, I know Plum Brook well. I've been inside it before. But even testing the 5m commercial fairings is cramped, let alone a much taller and wider 10m fairing. I'd argue there isn't enough room for a 10m by 30m fairing to be fully tested inside the space, since it needs room to actually separate, with all the mechanisms involved.

Heck, the doors are only 15m square. I don't see it realistically and fully being tested at Plum Brook, and I've never seen this realistically addressed.

10m fairings are a nightmare and likely to cost a fortune. How do you even transport them? Build them? Test them?

8.4m fairing even is a stretch (though isn't as absurd as 10m). My bet is SLS will fly only with Orion or the 5m fairing before being cancelled.

A 10m fairing can be moved by building it in three 120º parts. Assemble inside the vacuum test chamber.

How to environmentally test a payload that needs a 10m fairing is a different but related problem. New extra large test chamber?
Title: Re: SLS General Discussion Thread 2
Post by: Coastal Ron on 08/07/2016 08:16 PM
I keep getting irritated by the oft-repeated rubric that NASA is wasting money by developing a rocket that has no funded missions in the offing.

Not only funded, but no defined long-term need.  And by that I mean our political leadership has agreed to a goal that requires so much mass moved to space that a sustained need for an HLV is merited, and existing commercial capabilities cannot satisfy the goal.  None of that thinking has taken place or been agreed to.

Quote
Development of a launch capability is never done (with the exception of during Apollo, and even then was not initiated by a funded mission) because a series of funded flights require that capability.  You need to have the capability in place before you can start to fund the missions that will take advantage of it -- again, unless you want to repeat the heady go-for-broke days of Apollo.

No, the U.S. Government does not engage in that type of $B speculation without at least some sort of indication of demand, regardless how accurate or well done the study is.  And moving mass to space is now a mature industry, with the private sector here in the U.S. the master of this capability, not the U.S. Government.

So why does Congress want NASA to create a U.S. Government capability?  If there is a real need, it should be easy to quantify.

Quote
Just as a reminder, the F-1 engine originally went into development in 1955, based upon a perceived need by the Air Force to eventually be able to orbit large payloads.

Nineteen-fifty-five.  Two years before anyone, anywhere had even demonstrated the capability of orbiting anything.  At all.

From Wikipedia about the F-1 (https://en.wikipedia.org/wiki/Rocketdyne_F-1):

"The F-1 was originally developed by Rocketdyne to meet a 1955 U.S. Air Force requirement for a very large rocket engine."

So there was need.  And just to be clear, the military spends money differently than the civilian side of the government, so comparing the SLS to military rocket is apples-to-daisies.

Quote
In the case of SLS/Orion, I will also point out that two of the major elements of future crewed BLEO missions -- SLS and Orion -- are in development at the same time, and targeted to come online at the same time.

Well of course, they were created from the same source - the cancelled Constellation program.  Which still doesn't address what they are to used for, especially since the Orion is limited to going to the Moon for 21 day missions - and that is not a critical path requirement for going to Mars (i.e. the supposed prime destination NASA is focused on).

Quote
And there is funding now, this year, for early stages of DSH development.  So, it's not even as if we're building a rocket that has no crewed elements under development.

A Deep Space Habitat does not require an HLV.

And bottom line, what many people see is that "stuff" is being built to justify the SLS, not to address critical path items that are keeping us from getting to Mars (or whatever is NASA's top priority).

And if you have a capability that has to launch every 12 months (i.e. NASA's minimum safe flight cadence), then that means 70-130mT of "stuff" has to be in the funding pipeline years in advance.  It take years, and sometimes over a decade, for NASA to build space "stuff", and here we are just 6 years away from the SLS being operational - and there is a lack of "stuff" in the funding pipeline.

If the SLS truly was needed at this moment in history, you'd think we'd see more evidence of that need.

My $0.02
Title: Re: SLS General Discussion Thread 2
Post by: rayleighscatter on 08/07/2016 08:45 PM

So why does Congress want NASA to create a U.S. Government capability?  If there is a real need, it should be easy to quantify.
Like a manned space program?
Title: Re: SLS General Discussion Thread 2
Post by: Coastal Ron on 08/07/2016 11:24 PM

So why does Congress want NASA to create a U.S. Government capability?  If there is a real need, it should be easy to quantify.
Like a manned space program?

We have that today without an HLV.

There are NASA studies that show we could, if needed, go to Mars without an HLV - and studies that say an HLV would be an asset.

The deciding factor will be what the next President and Congress envision for NASA...
Title: Re: SLS General Discussion Thread 2
Post by: Space Ghost 1962 on 08/08/2016 12:28 AM
Rebuttal to your rant
I keep getting irritated by the oft-repeated rubric that NASA is wasting money by developing a rocket that has no funded missions in the offing.

Development of a launch capability is never done (with the exception of during Apollo, and even then was not initiated by a funded mission) because a series of funded flights require that capability.  You need to have the capability in place before you can start to fund the missions that will take advantage of it -- again, unless you want to repeat the heady go-for-broke days of Apollo.

Just as a reminder, the F-1 engine originally went into development in 1955, based upon a perceived need by the Air Force to eventually be able to orbit large payloads.
Before we knew what AF/country actually needed, which took a decade to resolve. We call this "risk reduction".

And the AF is still doing it. Look at recent co-investment in propulsion. Found a better, capital efficient way to do it. Far from immune to political attack.

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Again, unless you're running a crash program like Apollo, you don't start funding your missions until the rocket needed is designed and nearly ready to go.  And I will remind y'all that, in 1966, the only Apollo crewed missions that were specifically funded were AS-204 and AS-276.  All other Apollo missions funded in that time period were unmanned tests of the vehicles. 

Actually, if you read the view of John Logston, the American public did not support it, they endured it, as a means to respond to the perceived Soviet threat.

And the American public was not polarized but out of concern for threat, would unify even on things they were skeptical of, while still contending vigorously on things "in bounds". When Goldwater went "out of bounds", he got whacked for it, out of the need to have bounds so we'd not descend into chaos that a fast moving enemy might take advantage of. Unique times.

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While the only crewed mission to fly on SLS currently funded is EM-2, at a similar point in Apollo (which was a crash program in which all elements were being designed and built all at once) there was no funding specific to any crewed Saturn V launches, much less for actual lunar landing missions.  They weren't going to happen in the next fiscal year, and as such none of the funding was specific to any such missions.

Nope, not the same. "All up" testing ala George Mueller was a means to "catch up" with an "overwhelm and devastate" approach to belling a concern. Much more parallel development w/multiple primes. Clear mission focus, and overly singular goal with intended detachment (leave nothing in place for follow on).

There was a beginning, middle, and end. Period.

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In the case of SLS/Orion, I will also point out that two of the major elements of future crewed BLEO missions -- SLS and Orion -- are in development at the same time, and targeted to come online at the same time.  And there is funding now, this year, for early stages of DSH development.  So, it's not even as if we're building a rocket that has no crewed elements under development.

NASA has rightly objected to Congress building the wrong rocket. Because of lack of commitment to goal and regular funding for that goal. Due to the substantial lag time incurred by government rules  of operation from instigation to realization, which is in the order of DECADES in some cases, annual variation reduces efficiency, thus depressing an already depressed cycle of achievement. Not the proper way to use the tool of NASA.

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When y'all toss around the complaint "no funded missions," please recall Congress only funds things one fiscal year at a time (when they bother to do so at all and we don't just get stuck with a mess of CR's).  Apollo didn't have funded crewed lunar landing missions until fiscal 1969.  NASA had a longer-than-one-year plan for Apollo, and Congress appropriated for the new fiscal year based on what NASA told them were their needs to accomplish that plan.  That doesn't differ from what's happening right now, as NASA refines their DRA for Mars and presents funding requests based on accomplishing it without many "balloon" years needed to do so (i.e., with mostly flat budgets).  Congress has given them funding for the pieces they think they need to develop in the next fiscal year.

Read Logston. Not the same. Read his books and talk to him or me about it.

Here's a better view of what the issue is. Voters have been "educated" to believe that polarization is good, and that a "pure" view of things should dominate, and that letting other things (like space exploration) slide or be misappropriated is acceptable. That will be hard to change, as it is a 40 year trend that shows no change in sight.

If you want to run things back to the Apollo days, it's not the funding its the voter. You have to get from them, the same expectation that allowed Apollo to function as I and Logsdon have indicated.

If you were to do that, very little would need to be added to go forward, mostly any choice would work.

If you don't do that, absolutely no choice will make any difference.

In either case, NASA is caught in the middle and does the best it can do, while patiently explaining why things aren't working as well as they could.

add:

Read this (https://fivethirtyeight.com/features/the-political-process-isnt-rigged-it-has-much-bigger-problems/) about the problem mentioned above.
Title: Re: SLS General Discussion Thread 2
Post by: sdsds on 08/08/2016 01:16 AM
Would a payload like "Skylab II" (the same diameter as SLS) need a jettisoned fairing at all? Why not design it with an aerodynamic forward end?
Title: Re: SLS General Discussion Thread 2
Post by: Khadgars on 08/08/2016 02:02 AM
I keep getting irritated by the oft-repeated rubric that NASA is wasting money by developing a rocket that has no funded missions in the offing.

Development of a launch capability is never done (with the exception of during Apollo, and even then was not initiated by a funded mission) because a series of funded flights require that capability.  You need to have the capability in place before you can start to fund the missions that will take advantage of it -- again, unless you want to repeat the heady go-for-broke days of Apollo.

Just as a reminder, the F-1 engine originally went into development in 1955, based upon a perceived need by the Air Force to eventually be able to orbit large payloads.

Nineteen-fifty-five.  Two years before anyone, anywhere had even demonstrated the capability of orbiting anything.  At all.

If there was a funded mission that required an F-1 engine in 1955, I'd love to see the funding appropriation for it.

And, to be honest, I don't believe it would have been possible to seek funding for Apollo if there was not an F-1 class engine already under development.  If the U.S. had been forced to try and design Apollo without the F-1 having been under development for five years already, I don't think anyone would have bitten the bullet and committed to it.  One of the reasons Apollo was considered within the realm of possibility in 1961 was the fact that the F-1 engine was scheduled to become available by 1965 or so.

Again, unless you're running a crash program like Apollo, you don't start funding your missions until the rocket needed is designed and nearly ready to go.  And I will remind y'all that, in 1966, the only Apollo crewed missions that were specifically funded were AS-204 and AS-276.  All other Apollo missions funded in that time period were unmanned tests of the vehicles. 

While the only crewed mission to fly on SLS currently funded is EM-2, at a similar point in Apollo (which was a crash program in which all elements were being designed and built all at once) there was no funding specific to any crewed Saturn V launches, much less for actual lunar landing missions.  They weren't going to happen in the next fiscal year, and as such none of the funding was specific to any such missions.

In the case of SLS/Orion, I will also point out that two of the major elements of future crewed BLEO missions -- SLS and Orion -- are in development at the same time, and targeted to come online at the same time.  And there is funding now, this year, for early stages of DSH development.  So, it's not even as if we're building a rocket that has no crewed elements under development.

When y'all toss around the complaint "no funded missions," please recall Congress only funds things one fiscal year at a time (when they bother to do so at all and we don't just get stuck with a mess of CR's).  Apollo didn't have funded crewed lunar landing missions until fiscal 1969.  NASA had a longer-than-one-year plan for Apollo, and Congress appropriated for the new fiscal year based on what NASA told them were their needs to accomplish that plan.  That doesn't differ from what's happening right now, as NASA refines their DRA for Mars and presents funding requests based on accomplishing it without many "balloon" years needed to do so (i.e., with mostly flat budgets).  Congress has given them funding for the pieces they think they need to develop in the next fiscal year.

Now, you can complain that the DRA doesn't realistically define needs for new start funding on various vehicles and preliminary missions.  But that's a far different discussion than just continuing to insist SLS must die because there are no funded missions.

Rant mode off... ;)

Completely agree.  The goal post on which SLS/Orion is supposed to die changes every single year.  First is was a paper rocket and would never get out of pdf slides.  Then it was technical problems that would see it die like Ares I.  Then it was funding and political will.

Opponents of SLS/Orion could care less of its progress because they feel it shouldn't exist in the first place. 

I'm a huge SpaceX band-wagoner, I love their product and what they bring to the table.  But if opponents  think SpaceX has suddenly solved how to get to Mars at 1/10 the cost simply because they are willing to accept more risk, they're kidding themselves.

EM-1 is on schedule in two short years from now, and SpaceX's plate is completely full with just LEO's activities (Crewed Dragon and F9/H customer manifest).  Regardless of our positions, we need to be rooting for both SpaceX and NASA's plans as we're going to need both entities to get to the red planet.


Title: Re: SLS General Discussion Thread 2
Post by: Coastal Ron on 08/08/2016 05:28 AM
The goal post on which SLS/Orion is supposed to die changes every single year.

I think what has surprised many of us is the overall lack of interest Congress has had in starting the conversation about what the SLS is really supposed to do.  It was that point in time where I thought the real debate about the SLS would take place.  And yes, there are a couple of individual tasks being assigned to the SLS, but other than "we're going to Mars some day" there is no signature near-term need for the SLS.  Yet.

But with development getting closer to being done, an operational budget needs to be funded.  We'll see how Congress handles that.
 
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I'm a huge SpaceX band-wagoner, I love their product and what they bring to the table.  But if opponents  think SpaceX has suddenly solved how to get to Mars at 1/10 the cost simply because they are willing to accept more risk, they're kidding themselves.

What SpaceX does or doesn't do has no bearing on the future of the SLS.  Certainly not in the next few years.

That's because the SLS is a government-only transportation system, and really just a NASA-only transportation system.  So the justification for the SLS rests with what our politicians task NASA to do with it.  What the rest of the world (including SpaceX) does is immaterial.
Title: Re: SLS General Discussion Thread 2
Post by: Ben the Space Brit on 08/08/2016 09:55 AM
Would a payload like "Skylab II" (the same diameter as SLS) need a jettisoned fairing at all? Why not design it with an aerodynamic forward end?

That's what they did with Skylab but it didn't work out; damage was caused during launch and ascent to the sides of the module (insulation torn off along with a solar array). I don't know if it was caused by the slipstream but it does lead to the logical conclusion that you are wiser to protect side-mounted equipment from the airflow.
Title: Re: SLS General Discussion Thread 2
Post by: Proponent on 08/08/2016 04:33 PM
Completely agree.  The goal post on which SLS/Orion is supposed to die changes every single year.  First is was a paper rocket and would never get out of pdf slides.  Then it was technical problems that would see it die like Ares I.  Then it was funding and political will.

I, for one, have been consistently saying for years simply that its high cost means that it will likely never deliver much in the way of actual exploration.  Using it for significant exploration would appear to require large budget increases that are unlikely.
Title: Re: SLS General Discussion Thread 2
Post by: redliox on 08/08/2016 04:53 PM
how the heck are they going to test a 10m diameter fairing? Where? Or even an 8.4m fairing?

"You don't understand the power of the dark ... wait ... cost plus prime force ..." ;)

And that one won't come cheap. Also, the Skylab one didn't "fair" so well...

Thanks for the old Skylab deployment picture.  I actually wondered how it was stacked and deployed, especially with the solar telescope that stuck so oddly to one side.  So Skylab was half shrouded and the solar arrays were part of the un-shrouded section, correct?

Would a payload like "Skylab II" (the same diameter as SLS) need a jettisoned fairing at all? Why not design it with an aerodynamic forward end?

That's what they did with Skylab but it didn't work out; damage was caused during launch and ascent to the sides of the module (insulation torn off along with a solar array). I don't know if it was caused by the slipstream but it does lead to the logical conclusion that you are wiser to protect side-mounted equipment from the airflow.

Seeing how the Skylab was configured in launch form I see how the solar arrays were a bit vulnerable so I have to agree.  Had the arrays been installed on the sides of the shrouded docking adaptor that could have saved them and the grief of when one ripped off during ascent.  So any would-be Skylab 2 designs should keep arrays, radiators, ect tucked into a cocoon to play it safe.
Title: Re: SLS General Discussion Thread 2
Post by: Proponent on 08/08/2016 06:09 PM
Development of a launch capability is never done (with the exception of during Apollo, and even then was not initiated by a funded mission) because a series of funded flights require that capability.  You need to have the capability in place before you can start to fund the missions that will take advantage of it -- again, unless you want to repeat the heady go-for-broke days of Apollo.

I'm having a hard time thinking of a US launch vehicle that was developed with such an ill-defined need as SLS.  Vanguard and Juno I, for example, were developed expressly for launching particular earth satellites.  The Jupiter-, Thor-, Atlas- and Titan-based vehicles that succeeded them were developed in the knowledge that many payloads needed vehicles of such sizes.  The Saturns IB and V had very specific Apollo payloads and missions.  Just about every launch vehicle since -- Shuttle, Atlas variants, Delta IV, Falcon 9 -- has been aimed at an existing stream of payloads.  Antares is different, but it nonetheless had a very clearly defined mission, namely ISS logistics.

The one exception was the Saturn I, which was initially just a big first stage, with upper stages and payloads TBD.  But even then, nobody doubted that a larger launch capability was needed, and the Saturn I soon had the Army's Advent communications satellite and Dyna-Soar as payloads.  Today, on the other hand, there is no obvious need for an SLS-sized launch vehicle.  Even if you regard the US government as being serious about sending humans to Mars, the need, much less desirability, of SLS has not been established.  Nothing like the Apollo mode debate has occurred.

The fact that politicians have written SLS's specs into law and have legally mandated its use for BEO HSF and for Europa only feed the impression that they're really more interested in the rocket than in missions for it.
Title: Re: SLS General Discussion Thread 2
Post by: Proponent on 08/08/2016 07:31 PM
Quote
... unless you're running a crash program like Apollo, you don't start funding your missions until the rocket needed is designed and nearly ready to go.  And I will remind y'all that, in 1966, the only Apollo crewed missions that were specifically funded were AS-204 and AS-276.  All other Apollo missions funded in that time period were unmanned tests of the vehicles.

To amplify Space Ghost 1962's reply (https://forum.nasaspaceflight.com/index.php?action=profile;u=43786) on this point, have a look at NASA's plans for the Saturn V as of October 1962 (see p. 4 of the 1st attachment or, for fuller explanation a few months later, pp. 11 & 12 of the 2nd attachment).  Then compare that with a typical projection of SLS launches, e.g., the third attachment.  There's a world of difference between them.  When NASA ordered 15 Saturn V's in 1962, it had a plan for each one of them.  With SLS, the plan, even several years and $10+ billion in, is to launch every year or two with most payloads and missions TBD.  It really does seem to be a rocket looking for missions.  Even if missions are found, it hardly seems an efficient way of doing things, especially since all missions so far have been placed on SLS by legislative fiat.

EDIT:  "second attachment" -> "third attachment"
Title: Re: SLS General Discussion Thread 2
Post by: ncb1397 on 08/08/2016 07:39 PM
Quote
... unless you're running a crash program like Apollo, you don't start funding your missions until the rocket needed is designed and nearly ready to go.  And I will remind y'all that, in 1966, the only Apollo crewed missions that were specifically funded were AS-204 and AS-276.  All other Apollo missions funded in that time period were unmanned tests of the vehicles.

To amplify Space Ghost 1962's reply (https://forum.nasaspaceflight.com/index.php?action=profile;u=43786) on this point, have a look at NASA's plans for the Saturn V as of October 1962 (see p. 4 of the 1st attachment or, for fuller explanation a few months later, pp. 11 & 12 of the 2nd attachment).  Then compare that with a typical projection of SLS launches, e.g., the second attachment.  There's a world of difference between them.  When NASA ordered 15 Saturn V's in 1962, it had a plan for each one of them.  With SLS, the plan, even several years and $10+ billion in, is to launch every year or two with most payloads and missions TBD.  It really does seem to be a rocket looking for missions.  Even if missions are found, it hardly seems an efficient way of doing things, especially since all missions so far have been placed on SLS by legislative fiat.

SLS is specifically excluded for science missions by NASA management. That is the main reason there was none announced until congress stepped in. It is aggravating to read the NeMO study group state in one of their reports how they were directed to consider EELV class vehicles only and then go on to rule out possible mission goals due to mass or size constraints.

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Additionally, the Mars Exploration Program directed JPL to form an Orbiter Study Team to
assess various technical options for a 2022 Orbiter and to work with NEX-SAG regarding
potential mission capabilities (item f above). Launch vehicles were directed to be in the
Falcon 9/Atlas V class.

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NASA has been studying the development of even more powerful SEP systems, with a
view to their application for missions like ARRM. In this Exploration SEP option class
the spacecraft could carry a payload of mass 200-600 kg, powered by more than 5 kW.
At the higher end of capabilities in this class, the payload mass can be used to provide
enough fuel to bring the SEP-powered spacecraft out of low Mars orbit and to return
it to Earth vicinity. In that return option, the remote sensing payload would be
restricted to ~150 kg
and the Mars mission phase (including relay) would be
terminated after ~5 years.

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Ultra-high-resolution optical imaging (~5 cm/pixel) has great promise for science,
resources, and reconnaissance objectives. This is the resolution that bridges the gap
between the state of knowledge from orbital images, and knowledge from rover and
landed platforms. The challenges are for the size and mass of the optics and the
demands on the spacecraft for exceptional pointing and stability.

http://mepag.nasa.gov/reports/NEX-SAG_draft_v29_FINAL.pdf
Title: Re: SLS General Discussion Thread 2
Post by: Jim on 08/08/2016 07:40 PM
Development of a launch capability is never done (with the exception of during Apollo, and even then was not initiated by a funded mission) because a series of funded flights require that capability.  You need to have the capability in place before you can start to fund the missions that will take advantage of it -- again, unless you want to repeat the heady go-for-broke days of Apollo.

I'm having a hard time thinking of a US launch vehicle that was developed with such an ill-defined need as SLS.  Vanguard and Juno I, for example, were developed expressly for launching particular earth satellites.  The Jupiter-, Thor-, Atlas- and Titan-based vehicles that succeeded them were developed in the knowledge that many payloads needed vehicles of such sizes.  The Saturns IB and V had very specific Apollo payloads and missions.  Just about every launch vehicle since -- Shuttle, Atlas variants, Delta IV, Falcon 9 -- has been aimed at an existing stream of payloads.  Antares is different, but it nonetheless had a very clearly defined mission, namely ISS logistics.

The one exception was the Saturn I, which was initially just a big first stage, with upper stages and payloads TBD.  But even then, nobody doubted that a larger launch capability was needed, and the Saturn I soon had the Army's Advent communications satellite and Dyna-Soar as payloads.  Today, on the other hand, there is no obvious need for an SLS-sized launch vehicle.  Even if you regard the US government as being serious about sending humans to Mars, the need, much less desirability, of SLS has not been established.  Nothing like the Apollo mode debate has occurred.

The fact that politicians have written SLS's specs into law and have legally mandated its use for BEO HSF and for Europa only feed the impression that they're really more interested in the rocket than in missions for it.

Payloads drive launch vehicle requirements.  Any upgrades or new vehicles in the last 50 years have been driven by the needs of a payload.  There was no build it and they will come.
Title: Re: SLS General Discussion Thread 2
Post by: Proponent on 08/08/2016 08:45 PM
SLS is specifically excluded for science missions by NASA management. That is the main reason there was none announced until congress stepped in. It is aggravating to read the NeMO study group state in one of their reports how they were directed to consider EELV class vehicles only and then go on to rule out possible mission goals due to mass or size constraints.

There is nothing new or unusual about spacecraft having to meet mass constraints.  Establishing a launch-vehicle class for Mars missions is essentially setting a size and cost limit: even ignoring the cost of the much larger launch vehicle, an SLS-sized Mars mission will be a much larger and more expensive spacecraft. 

The Europa mission is different in that the use of SLS affects principally trajectory and mission duration rather spacecraft size.  Although an SLS launch is more expensive than an Atlas V launch, the shorter duration of the SLS-boosted mission does make it cheaper in some respects.  Whether the use of SLS in place of Atlas V reduces total costs, I don't know, and, as far as I can tell, Congress is not interested in that question.
Title: Re: SLS General Discussion Thread 2
Post by: Proponent on 08/08/2016 08:46 PM
Payloads drive launch vehicle requirements.  Any upgrades or new vehicles in the last 50 years have been driven by the needs of a payload.  There was no build it and they will come.

I thought that was pretty much what I said, with the partial exception of the Saturn I.
Title: Re: SLS General Discussion Thread 2
Post by: Danny Dot on 08/09/2016 04:44 PM
Completely agree.  The goal post on which SLS/Orion is supposed to die changes every single year.  First is was a paper rocket and would never get out of pdf slides.  Then it was technical problems that would see it die like Ares I.  Then it was funding and political will.

I, for one, have been consistently saying for years simply that its high cost means that it will likely never deliver much in the way of actual exploration.  Using it for significant exploration would appear to require large budget increases that are unlikely.

And don't forget the very high cost of any exploration spacecraft that is big enough to justify SLS over a Delta IV heavy.  We are talking many billions of dollars.

Title: Re: SLS General Discussion Thread 2
Post by: yg1968 on 08/09/2016 04:49 PM
Completely agree.  The goal post on which SLS/Orion is supposed to die changes every single year.  First is was a paper rocket and would never get out of pdf slides.  Then it was technical problems that would see it die like Ares I.  Then it was funding and political will.

I, for one, have been consistently saying for years simply that its high cost means that it will likely never deliver much in the way of actual exploration.  Using it for significant exploration would appear to require large budget increases that are unlikely.

Not just you. The biggest criticism of SLS has always been the lack of payload for it.
Title: Re: SLS General Discussion Thread 2
Post by: the_other_Doug on 08/09/2016 05:38 PM
Too many good (and not-so-good) points to pull one post out and reply to it individually, so here's a few thoughts on the discussion at this point.

Ron (and others), I hear you about what you, I, this forum, Congress, the Administration and NASA perceive as a "need" for SLS.  But note the various entities I mentioned -- they are different, serve different functions, and answer to much different constituencies.  (Thankfully, none of us here have to answer to anybody for expressing our opinions... :D )

NASA has a very specific, clearly defined need for SLS.  It is defined in the latest version of their Mars DRA.  To say that NASA has no plans to go to Mars is ridiculous -- they have had plans for decades, and keep updating and refining them.  The DRA is the "overarching vision" for Mars exploration that some people below insist doesn't exist.  NASA presents this vision before Congress every time they go to talk to them.  In this way, it's not much different from how NASA presented the Apollo DRM as their overarching plan for landing people on the Moon, back when the Kennedy and Johnson Administrations were requesting current fiscal year funding for what was needed right now to achieve that vision.

You can argue that a variety of constituencies don't agree with, or support, the current NASA Mars DRA, you can argue that it doesn't have enough political support to get funded throughout the remaining 20-some years before crewed operations could begin, you can argue a lot of things.  But you can't argue that a vision doesn't exist, or that this vision doesn't drive what NASA is asking for in re appropriations that they feel will lead to a crewed Mars exploration program in the 2030's.

To Ron specifically -- you mention that there is no need for a government-built HLV because the same NASA Mars DRA can be accomplished using commercial vehicles, and then you refute yourself by saying that NASA is not in the business of designing DRAs that use commercial vehicles, they are in the business of doing Mars missions by building their own rockets and spacecraft.  C'mon, it has to be one or the other.

Also, many of you make the point that SLS and Orion are currently in development because they are what ended up falling out of the failed Constellation program.  So, just in terms of the conditions extant when these development programs began, there wasn't a commercial HLV (or, at least, anything approaching the perceived HLV need in the DRA) available.  You couldn't in 2001 -- or even 2009 -- say "Hey, let's dump this SLS and just plan on using a Falcon Heavy for this DRA," because not only was FH not an option, it wasn't even a notional launch vehicle at those times.  And is still not a proven HLV asset available to anyone, yet.  (Soon, though, hopefully... fingers crossed...)

Finally -- in what manner would y'all believe Congress could or would have a committed, funded project to land humans on Mars?  Do you want a Congressional funding bill passed that guarantees half a trillion dollars in funding over the next 20 years?  Do you want a crash commitment, with a $100 billion this-fiscal-year supplemental appropriation, to get all the elements ready to launch before SpaceX can beat them to it?

Do you want or expect politicians who can't be guaranteed to still be in power, or even alive (a lot of them are in their 60s and 70s) in 20 years, when there will be a noticeable payoff from the investment, to get behind a 20-year funding plan?

Do you expect any Administration to propose anything they perceive cannot be accomplished during a max two-term (eight-year) period?  Can you name any President in the past 60 years who has proposed anything he knew could not be accomplished during his own Presidency?

And, in the past 20 years, have we even had a federal government that is capable of accomplishing any planning beyond the ends of their noses?  Some agencies and administrations within the government have managed to maintain their planning and operations functions amidst the total breakdown of at least two of the three branches of government, but I can't see any indication that any Administration or Congress in at least 20 years has been able to agree on any kind of planning that goes more than a fiscal year out.  The few long-term commitments we've seen have been in defense projects (no surprise), and even those have been rarer and rarer as polarization spreads its tentacles even into the Pentagon.

I'm thinking that the USG at present is incapable of delivering the commitment y'all seem to be looking for.  I also think that you won't see any Administration go to Congress asking for funding leading directly to a manned Mars expedition until and unless the remaining investment required can be made, and the work accomplished, within the eight-year, two-term expectation of that Administration being in power.  And that's under the best of circumstances, assuming we culturally manage to reject politics of polarization and learn to work together to achieve a common goal.

And even then, such a program will need to have at least enough political support, if not popular support, to get the remaining funding through Congress.  There will need to be a really good PR case made to the American people to sway the latter.  Pork may be enough to persuade the former.

But -- if you can get the funding and support, even if just to keep the pork rolling, to develop and build many of the needed pieces to fly the DRA, you can get to within that eight-year mark of the finish line.  Only then are you going to see the commitment y'all are looking for, I think.

That's my view on it, anyway.  YMMV.  :)
Title: Re: SLS General Discussion Thread 2
Post by: Kansan52 on 08/09/2016 06:36 PM
Bucks. Once again it comes to Bucks. The discussion has pointed this out time and again. The aspect of Constellation I despised was it largely strip all other parts of NASA (including the ISS) to fund Constellation.

IMHO, that is the same now. Congress does not want to increase NASA's budget. A Public mandate for an increase does not exist. Any progress for SLS payloads will be constrained by the budget.
Title: Re: SLS General Discussion Thread 2
Post by: Coastal Ron on 08/09/2016 06:39 PM
Do you expect any Administration to propose anything they perceive cannot be accomplished during a max two-term (eight-year) period?  Can you name any President in the past 60 years who has proposed anything he knew could not be accomplished during his own Presidency?

Apollo - proposed in Kennedy's first term in office, and his goal was two years outside of his possible last term in office.

Shuttle - formally commenced in 1972, the year Nixon was running for his 2nd term in office.  No way anyone would have expected the Shuttle to start operational flights in just 4 years.

The ISS - when Reagan proposed Space Station Freedom during his 1984 State of the Union Address, he could have only expected preliminary work to have been done on it before he left office.

Constellation program - Bush proposed the Vision for Space Exploration (VSE) in 2004, just before his re-election.  The goal was to return to the Moon 12 years after he left office.

So yes, many Presidents have proposed efforts in space that would not have reached space until after their time in office had ended.
Title: Re: SLS General Discussion Thread 2
Post by: Space Ghost 1962 on 08/09/2016 07:09 PM
Payloads drive launch vehicle requirements.  Any upgrades or new vehicles in the last 50 years have been driven by the needs of a payload.  There was no build it and they will come.

The best answer here.

And it isn't that hard to consider the payload. With Saturn V it was a lunar stack, with Shuttle it was a space station.

So, lets say the aggregate payload is a Mars surface expedition. You'll have a sequence of launches to get it there. Next, you go find the way to get it there.

If you don't, too easy to not do the mission for too many reasons.

A solid objective (Moon, Station, ... Mars?) delivers solid missions using solid SC that require launch capability. Hand please meet glove.

Now ... why doesn't that occur? Blame game. We don't really want to set the objective because we'll be blamed for consuming the budget, and possibly won't continue because it'll get "Proxmired" by someone part way through. Congress can't even agree on lunch at noon today, and now they'd have to agree for more than a decade.

So they build what they think John Q Public want's to see, hang a sign on it as "world's biggest rocket", and tell NASA to use it somehow, then be critical of what follows. Leadership.

Can you make it work? Possibly. We could have done Moon/Station with Titian too, but it likely would have taken a lot longer, perhaps two decades and a couple of stations - Korolev had similar notions. Apollo was a genuine plan by a leader to get there in a decade, and along the way the Saturn V became the LV that got it and the LM there.

It's not the absence of the payloads as much as the absence of the leadership/objective/plan/commitment that makes those payloads/missions to use them.
Title: Re: SLS General Discussion Thread 2
Post by: the_other_Doug