Author Topic: What does it take to effectively replace the SLS in NASA's BLEO plans?  (Read 3619 times)

We all know both the virtues and the demerits of SLS and its development.
On the negative side its surging costs, the lack of agility and flexibility in the program, the delays.
On the positive side its capabilities for deep space.

Note: I strongly believe that 'pork barrel politics' isn't the only thing that keeps SLS afloat, for two reasons at least.
1- People inside NASA and studies made by NASA see its capabilities as necessary to sustain BLEO exploration, and the US private space industry of 2010 was in a state that made NASA and govt funding the only way to develop those capabilities;
2- 'Pork barrel politics' would also apply by shifting SLS' missions to commercial rockets, essentially supporting Boeing, Lockheed Martin,  SpaceX, Blue Origin and potentially other players and local economies. Lobbies could be overcome if it's clear that equivalent (or better), yet cheaper systems than SLS have the same (or better) chances of being ready for NASA's plans in time.

So, why isn't there a major political drive (and NASA drive) to cancel the SLS?
To me the answer is that they still don't think the US private space industry is willing to spontaneously invest and provide the capabilities needed to substitute the SLS without traditional cost-plus LV development aka SLS itself.

Therefore, the crucial question to back its cancellation to me is: what does it take to replace those capabilities? How likely is it that the private industry is able/willing to meet those requirements in a timeline that matches (or precedes) the one that is planned for SLS (and accounting for schedule delays, to which nor SLS nor commercial systems are immune) without traditional cost-plus NASA funding?

Now, keep in mind that, for the foreseeable future, SLS plans are essentially the deployment and operation of the DSG and Europa Clipper.
Since both EC and the deployment of DSG's propulsion module can be done with currently available LVs, SLS exclusive capabilities aren't needed until 2024-2025 in current plans.

We have FH flying, Vulcan ACES, New Glenn, BFR in development, New Armstrong on the drawing board, so commitment is there and redundancy too.

With that said, the main questions I would like to bring with this thread are:
-How likely is it that the private industry will be able to substitute the SLS in practice by 2025 without traditional cost-plus NASA funding?
-What does it take to support Orion + the deployment of the DSG without the SLS, are those 'commercial' systems enough (as they are or with little NASA funded modifications)?
-Is the diversity and abundance of SHLVs in commercial development enough to provide the low risk and low schedule uncertainty necessary to sustain SLS' cancelation?


IMO the answer is yes, and the only thing that explains the continued support towards SLS both by NASA and the Congress is that they still don't believe that things have changed and private entities are now investing their own money on SHLVs and BLEO capabilities, and that NASA doesn't have to completely fund these capabilities on its own dime anymore.

Edit: this is my first thread on Space Policy  and I'm by no means an insider so forgive me if I'm being a bit naive, but I think some of these may be interesting points to discuss ;D
« Last Edit: 02/23/2018 12:39 PM by AbuSimbel »
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And a follow-up question tangential to the topic:
Excluding New Armstrong and the BFR, which the establishment may see as pipe dreams, I often hear that it wouldn't be possible to replicate EM-3, 4 etc. with FH, New Glenn, Vulcan ACES because launching Orion and the DGS modules separately would require extensive modifications to DSG's design. Is it true? I've yet to find a definitive answer.
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Online speedevil

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I cannot find an even slightly current breakdown of payload masses of EM* missions - is there one?

I cannot find an even slightly current breakdown of payload masses of EM* missions - is there one?
This is what Chris G.'s April 2017 article ( https://www.nasaspaceflight.com/2017/04/nasa-goals-missions-sls-eyes-multi-step-mars/ ) has:



< 10ton (13 ton for Block II) for each Co-manifested DSG module in every manned EM mission, then a < 41ton self propelled module to be launched on EM-6 with SLS Ib in its cargo configuration and similarly heavy payloads for cargo-only EM-8 and EM-10 (but we would probably be into the 2030s for these).

However I understand that none of these payloads has publicly available specifications and even the 1st module, the Propulsion module, slated to launch in 2023-24 isn't exactly in an advanced state of design.

« Last Edit: 02/23/2018 01:34 PM by AbuSimbel »
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Offline RonM

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Vulcan, New Glenn, and BFR will most likely be operational in the middle of the next decade. FH had its first test flight and will soon be operational. While it's highly unlikely all these rockets will fail, Congress probably won't even consider cancelling SLS until commercial options are operational and proven (several successful launches). So, we'll at least get up to EM-2.

Depending on how commercial crew progresses, Congress may insist on Orion even if they cancel SLS. The potential game changer is BFS crew.

Offline mike robel

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1.  Money
2.  Congress deciding to change the law requiring development of SLS.
3.  NASA becoming more open to adopt out of house solutions to mission accomplishment.

Offline Rocket Science

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Let's use the previous wish to use the reliable commercial fleet of existing LVs going back a decade more with Atlas and Delta for crewed flights to LEO and ISS... How did that work out?
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Online AncientU

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I think the premise that NASA's BLEO Plan is the optimum way to go about 'deep space exploration' is false.

What is needed is a re-evaluation of how we should go about getting beyond LEO, starting today, with mid (5-7 years) and long term (10-15 years) goals of permanent presence on the Moon and humans to Mars, respectively.  SLS can be part of the launch mix if it successfully competes with then-existing launchers as the program and private launch vehicles develop.

Anyone/everyone interested in 'deep space exploration' could and should pull in the same direction towards this goal.
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Offline Rocket Science

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As long as we have eccentric (let's face it  ;D) Billionaires willing to build rockets to go places why do we even have to be concerned as to what will it take to replace SLS... The new players just have to continue to do what they are doing designing and flying reliable LVs and given enough time SLS may just fade into obscurity... I only feel bad for the efforts of a lot of good people, many who are young, that continue to give their best efforts on the program and have yet to see the fruits of their labor leave the ground...
"The laws of physics are unforgiving"
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1.  Money
2.  Congress deciding to change the law requiring development of SLS.
3.  NASA becoming more open to adopt out of house solutions to mission accomplishment.
Money for sure, but considerably less (from NASA) than with SLS. Congress seems to be a tough one.
But about 3, would it really be that outside of NASA's comfort zone to use out of house LVs?
I mean Orion is another matter and I think they should keep it at least until other innovative manned alternatives (BFR, whatever BO comes with for cislunar) get proven and demonstrate their reliability. But LVs? They've certified LVs for high value missions and are certifying F9 (relatively new) and Atlas for manned missions too.
Would they be that uncomfortable using FH, Vulcan, NG to fly Orion and the DSG after the usual certification?

Let's use the previous wish to use the reliable commercial fleet of existing LVs going back a decade more with Atlas and Delta for crewed flights to LEO and ISS... How did that work out?
Well what I'm saying is more like COTS than commercial crew, perhaps even more lightweight than COTS. No need for NASA to get too involved: the commercial SHLVs are already flying or being developed. NASA doesn't need to dictate and pay for a multitude of low level requirements: all they have to do IMO is acknowledge them first, maybe give them some incentive if needed, certify them and give them missions. Given the redundancy I think this would be a way safer bet than Commercial Crew (and even that isn't really going that bad vs other programs).
« Last Edit: 02/23/2018 03:23 PM by AbuSimbel »
Failure is not only an option, it's the only way to learn.
"Tradition is not the worship of ashes, but the custody of fire" - Gustav Mahler

As long as we have eccentric (let's face it  ;D) Billionaires willing to build rockets to go places why do we even have to be concerned as to what will it take to replace SLS... The new players just have to continue to do what they are doing designing and flying reliable LVs and given enough time SLS may just fade into obscurity... I only feel bad for the efforts of a lot of good people, many who are young, that continue to give their best efforts on the program and have yet to see the fruits of their labor leave the ground...

Yeah I feel bad for them too, and think that a solid exploration plan that leverages commercial launchers would be more satisfying (and actually deliver more) for them too  ;D
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Offline Rocket Science

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1.  Money
2.  Congress deciding to change the law requiring development of SLS.
3.  NASA becoming more open to adopt out of house solutions to mission accomplishment.
Money for sure, but considerably less (from NASA) than with SLS. Congress seems to be a tough one.
But about 3, would it really be that outside of NASA's comfort zone to use out of house LVs?
I mean Orion is another matter and I think they should keep it at least until other innovative manned alternatives (BFR, whatever BO comes with for cislunar) get proven and demonstrate their reliability. But LVs? They've certified LVs for high value missions and are certifying F9 (relatively new) and Atlas for manned missions too.
Would they be that uncomfortable using FH, Vulcan, NG to fly Orion and the DSG after the usual certification?

Let's use the previous wish to use the reliable commercial fleet of existing LVs going back a decade more with Atlas and Delta for crewed flights to LEO and ISS... How did that work out?
Well what I'm saying is more like COTS than commercial crew, perhaps even more lightweight than COTS. No need for NASA to get too involved: the commercial SHLVs are already flying or being developed. NASA doesn't need to dictate and pay for man low level requirements: all they have to do IMO is acknowledge them first, maybe give them some incentive if needed, certify them and give them missions. Given the redundancy I think this would be a way safer bet than Commercial Crew (and even that isn't really going that bad vs other programs).
As long as they are NASA astronauts you are going to have issues (see ASAP)... Now for example, if it's a SpaceX mission with SpaceX crews who are willing to take their own risk, NASA has no say in it and all they can do is wave bye bye from the view port of ISS...
« Last Edit: 02/23/2018 03:26 PM by Rocket Science »
"The laws of physics are unforgiving"
~Rob: Physics instructor, Aviator, Vintage auto racer

I think the premise that NASA's BLEO Plan is the optimum way to go about 'deep space exploration' is false.

What is needed is a re-evaluation of how we should go about getting beyond LEO, starting today, with mid (5-7 years) and long term (10-15 years) goals of permanent presence on the Moon and humans to Mars, respectively.  SLS can be part of the launch mix if it successfully competes with then-existing launchers as the program and private launch vehicles develop.

Anyone/everyone interested in 'deep space exploration' could and should pull in the same direction towards this goal.
I don't think it's the optimal plan too, but it has support, even internationally and it actually doesn't have to be the optimal plan.
The good thing of this recent change in the US space industry is that NASA's plan is no longer the only BLEO exploration plan.
This is a good thing. Multiple plans with different aims and objectives can coexist, no need to collapse them all into a single one.

The DSG has different objectives than SpaceX's or BO's to be announced architecture, but they're valid nonetheless.
The thing is that it's now pretty clear that SLS will not be competitive with other SHLVs (existing and in development) and it's not, IMO, the right choice to enable either BLEO plan.
Failure is not only an option, it's the only way to learn.
"Tradition is not the worship of ashes, but the custody of fire" - Gustav Mahler

1.  Money
2.  Congress deciding to change the law requiring development of SLS.
3.  NASA becoming more open to adopt out of house solutions to mission accomplishment.
Money for sure, but considerably less (from NASA) than with SLS. Congress seems to be a tough one.
But about 3, would it really be that outside of NASA's comfort zone to use out of house LVs?
I mean Orion is another matter and I think they should keep it at least until other innovative manned alternatives (BFR, whatever BO comes with for cislunar) get proven and demonstrate their reliability. But LVs? They've certified LVs for high value missions and are certifying F9 (relatively new) and Atlas for manned missions too.
Would they be that uncomfortable using FH, Vulcan, NG to fly Orion and the DSG after the usual certification?

Let's use the previous wish to use the reliable commercial fleet of existing LVs going back a decade more with Atlas and Delta for crewed flights to LEO and ISS... How did that work out?
Well what I'm saying is more like COTS than commercial crew, perhaps even more lightweight than COTS. No need for NASA to get too involved: the commercial SHLVs are already flying or being developed. NASA doesn't need to dictate and pay for man low level requirements: all they have to do IMO is acknowledge them first, maybe give them some incentive if needed, certify them and give them missions. Given the redundancy I think this would be a way safer bet than Commercial Crew (and even that isn't really going that bad vs other programs).
As long as they are NASA astronauts you are going to have issues (see ASAP)... Now for example, if it's a SpaceX mission with SpaceX crews who are willing to take their own risk, NASA has no say in it and all they can do is wave bye bye from the view port of ISS...
True, but are those issues this difficult to overcome by 2025? I mean ASAP will most likely let people fly on F9, sure they require their 7 Block 5 flights, but then everything is good to go. Will it be much more difficult to fly Orion on Vulcan ACES, New Glenn, even a NASA funded FH with modified US if they wanted maximum redundancy? Seven years to the first planned and useful SLS manned mission are a long time (given how EM-2 doesn't really need crew nor Orion to deploy the propulsion module) to find a replacement.
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Offline Rocket Science

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1.  Money
2.  Congress deciding to change the law requiring development of SLS.
3.  NASA becoming more open to adopt out of house solutions to mission accomplishment.
Money for sure, but considerably less (from NASA) than with SLS. Congress seems to be a tough one.
But about 3, would it really be that outside of NASA's comfort zone to use out of house LVs?
I mean Orion is another matter and I think they should keep it at least until other innovative manned alternatives (BFR, whatever BO comes with for cislunar) get proven and demonstrate their reliability. But LVs? They've certified LVs for high value missions and are certifying F9 (relatively new) and Atlas for manned missions too.
Would they be that uncomfortable using FH, Vulcan, NG to fly Orion and the DSG after the usual certification?

Let's use the previous wish to use the reliable commercial fleet of existing LVs going back a decade more with Atlas and Delta for crewed flights to LEO and ISS... How did that work out?
Well what I'm saying is more like COTS than commercial crew, perhaps even more lightweight than COTS. No need for NASA to get too involved: the commercial SHLVs are already flying or being developed. NASA doesn't need to dictate and pay for man low level requirements: all they have to do IMO is acknowledge them first, maybe give them some incentive if needed, certify them and give them missions. Given the redundancy I think this would be a way safer bet than Commercial Crew (and even that isn't really going that bad vs other programs).
As long as they are NASA astronauts you are going to have issues (see ASAP)... Now for example, if it's a SpaceX mission with SpaceX crews who are willing to take their own risk, NASA has no say in it and all they can do is wave bye bye from the view port of ISS...
True, but are those issues this difficult to overcome by 2025? I mean ASAP will most likely let people fly on F9, sure they require their 7 Block 5 flights, but then everything is good to go. Will it be much more difficult to fly Orion on Vulcan ACES, New Glenn, even a NASA funded FH with modified US if they wanted maximum redundancy? Seven years to the first planned and useful SLS manned mission are a long time (given how EM-2 doesn't really need crew nor Orion to deploy the propulsion module) to find a replacement.
The issue is political, not technical for NASA crews... ASAP gives advice, reviews etc... It doesn't have a say in who flys on what and has no authority...
"The laws of physics are unforgiving"
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Offline DJPledger

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BO needs to offer NA to NASA as SLS replacement without asking NASA for any funding as Bezos can fund it's dev. all by himself. SpaceX could also pitch in with their BFR. NASA just pays for using NA and BFR. NASA will be able to do far more for a given amount of money using NA and BFR than with the money bleeding SLS.

Offline Kansan52

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On thing that stands out for me is the idea that ending the SLS program will automatically free money for programs that can be launched by something other than SLS.

No SLS could also mean that the money for SLS will be removed from NASA's budget and swallowed by some other US government program.

So still no vehicles, no DSG, no landers...

Offline DJPledger

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On thing that stands out for me is the idea that ending the SLS program will automatically free money for programs that can be launched by something other than SLS.

No SLS could also mean that the money for SLS will be removed from NASA's budget and swallowed by some other US government program.

So still no vehicles, no DSG, no landers...
Bezos can fund dev. of NA from his own pocket so there would still be NA irrespective of what happens to NASA's budget after SLS is cancelled. Also if Starlink works and brings in the money then BFR will be dev. without the need for any gov. money. NASA just pays to use commercial vehicles for all of it's future missions. Just no NASA dev. vehicles. Or even NASA could be eventually disbanded and all future space exploration will be commercial.

On thing that stands out for me is the idea that ending the SLS program will automatically free money for programs that can be launched by something other than SLS.

No SLS could also mean that the money for SLS will be removed from NASA's budget and swallowed by some other US government program.

So still no vehicles, no DSG, no landers...

Frankly I'm not a US policy expert like many here, but given how the whole 'Deep Space Exploration', 'JourneytoMars', 'Back to the Moon' PR is about the only PR thing that NASA has to gather broad political support, and the only thing most administrations seem to care about as a matter of nationalistic pride, I would greatly doubt that ceasing funding for the SLS would mean canceling the Deep Space Exploration program altogether.
They'll cancel the SLS only if they feel it can be replaced by viable alternatives and keep funding Deep Space Missions, if anything to further the message of american leadership in space.

And even if they did exactly what you say, SLS cancellation would happen only if the rocket is considered useless, so cutting its budget would mean cutting useless expenses regardless of whether the money gets reallocated or stays within NASA. And I strongly doubt the former would be the case, at least not completely: it would be possible to cut NASA's overall budget by canceling SLS and still increase the BLEO missions budget, given how costly the program is.
« Last Edit: 02/24/2018 10:37 AM by AbuSimbel »
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Offline Ronsmytheiii

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And even if they did exactly what you say, SLS cancellation would happen only if the rocket is considered useless, so cutting its budget would mean cutting useless expenses regardless of whether the money gets reallocated or stays within NASA. And I strongly doubt the former would be the case, at least not completely: it would be possible to cut NASA's overall budget by canceling SLS and still increase the BLEO missions budget, given how costly the program is.

That wouldn't happen. If you cancel SLS without a big government HSF program, Congress will just come up with another. Congress has consistently shown its willingness to dictate space policy for two administrations now in the following cycle:

1) president decides to cut large, govt HSF program. Announces private HSF program to go "beyond LEO"
2) Congress members from NASA districts are concerned about lack of job security for their voters, same for traditional aerospace companies
3) Administration vaguely comes up with ideas, nothing that satisfies Congress
4) congress comes up with big program to protect said jobs in their districts (kind of their job to do that)
5) Administration gives up and agrees, they aren't that invested in reinventing space.

So unless you show a big government program with lots of NEW jobs in their districts, Congress will just come up with a "Son of SLS" and repeat the cycle.

Edit: Also, if SLS "fails" don't see anyone in Congress willing to keep NASA funding anywhere near what they do currently for a BLEO program.
« Last Edit: 02/25/2018 09:51 AM by Ronsmytheiii »
And this is a good reminder that just because one of your fellow space enthusiasts occasionally voices doubts about the SpaceX schedule announcements or is cautious about believing SpaceX has licked a problem before actually seeing proof that's true, it doesn't mean they hate SpaceX.

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