How often can the SLS system launch with just one launchpad? I believe the general idea is that it will only launch once a year, but could it be (With the nessacary funding!) moved up to launch twice a year, or even three times a year?
And recall that the Saturn V and LC-39 were both designed for launch every 60 days or so, thus the two pads (and initial plans for a third). In fact, they only used 39B for one single launch in mainline Apollo, that being for Apollo 10. The fastest turnaround time for a Saturn V at a given launch pad was between Apollos 8 and 9. They both launched out of 39A, and launched roughly nine weeks apart. Apollo 10 was rolled out to 39B right around the time of Apollo 9, and it is well-known that Apollo 11 was rolled out to 39A while Apollo 10 was still in flight.After Apollo 11, the shortest time between two Saturn V launches was four months, which left plenty of time to clean up 39A and get it ready for the next launch. As I've pointed out before, except for the Big Push of the first half of 1969, NASA never launched Saturn V's at a rate higher than two a year, which is the highest launch rate anyone really postulates for SLS.If you make the assumption that SLS will be roughly equivalent in terms of stacking, prep, launch and pad clean-up to the Saturn V, there will be no problems at all in supporting a flight rate of up to three a year using just 39B. The limiting factor on SLS launch rate is the production rate for the cores, which is now set to support between one and two launches a year.SLS could be launched at a rate of four (to maybe up to six, with a lot of pushing) a year, in terms of the pad infrastructure, I think, but that would require spending up to a decade manufacturing all of the SLS cores, SRMs, upper stages, etc., and putting them in storage to await the high-rate period. So, if you developed a DRA for Mars that required, say, eight SLS launches in two years, it could likely be done -- but you'd have to start making the SLS stages, as fast as your manufacturing facilities allow, right now, and couldn't start launching them for another decade or so...
So two is the most you can get without having to wait a few years to build a sulplus... that seems sensable.
So that would allow for a Mission every year to the moon (Not out the question if NASA was to make a Reusable lander) plus an extra booster for Europa missions, or assembling a NEO mission if congress was to fund it.
What will determine whether the SLS truly reaches any sort of launch cadence is whether there is enough "demand" for it's unique services. And "demand" means funding from Congress to build a continuous stream of SLS-only payloads.None of those have been fully funded by Congress yet, and if you look at NASA's history of building even small complex payloads, the SLS will be sitting around for a number of years waiting for something to do. For instance the 3.8mT Mars Science Laboratory (MSL) took 7 years from proposal to launch, and the Orion spacecraft will have taken 18 years by the time it flies with humans.The SLS is supposed to be operational around 2023, which is just 7 years away - see the challenge?
Quote from: Coastal Ron on 05/21/2016 10:16 pm... For instance the 3.8mT Mars Science Laboratory (MSL) took 7 years from proposal to launch, and the Orion spacecraft will have taken 18 years by the time it flies with humans.The SLS is supposed to be operational around 2023, which is just 7 years away - see the challenge?Those 7 years will probably be quite awkward; the joys of seeing what the next President demands coupled with building the first few sets of vehicles. I don't think it would be outright canceled, but hopefully in that time they set payloads even if it flies a half-dozen times.
... For instance the 3.8mT Mars Science Laboratory (MSL) took 7 years from proposal to launch, and the Orion spacecraft will have taken 18 years by the time it flies with humans.The SLS is supposed to be operational around 2023, which is just 7 years away - see the challenge?
This is not something that you can complete and just put aside until you need it. Maintaining the launch capability and training the workforce will cost billions per year even if it never flies.
Quote from: redliox on 05/21/2016 10:48 pmQuote from: Coastal Ron on 05/21/2016 10:16 pm... For instance the 3.8mT Mars Science Laboratory (MSL) took 7 years from proposal to launch, and the Orion spacecraft will have taken 18 years by the time it flies with humans.The SLS is supposed to be operational around 2023, which is just 7 years away - see the challenge?Those 7 years will probably be quite awkward; the joys of seeing what the next President demands coupled with building the first few sets of vehicles. I don't think it would be outright canceled, but hopefully in that time they set payloads even if it flies a half-dozen times.If it doesn't fly, it will be cancelled. NASA and Congress can not afford to have it ready for launch but not actually launch for several years. This is not something that you can complete and just put aside until you need it. Maintaining the launch capability and training the workforce will cost billions per year even if it never flies.
One reason I wonder if they should have went with Shuttle-C as the Shuttle was able to launch 9 times a year.The long pole in getting a more directly shuttle derived LV into the same flight rates would be SSME production.
Quote from: Patchouli on 05/23/2016 03:49 pmOne reason I wonder if they should have went with Shuttle-C as the Shuttle was able to launch 9 times a year.The long pole in getting a more directly shuttle derived LV into the same flight rates would be SSME production.If you went that route, make it a drone orbiter. If the old design orbiters where being improved with tougher tiles. Reusing a newly built orbiter with the latest techniques would mean even the original SSMEs would be enough.With enough money, anything is possible.
Unfortunately it looks like Pork is a powerful propellant for SLS. God knows how far it can propell the SLS - to Europa and beyond ?
As I understand it, the Eastern Range needs a couple of days to recycle its status after every launch. The question is 'what is the maximum possible production rate' combined with 'how long does a nominal pad flow (launch to launch) for the VAB and LC-39B take?"Other than that, it's just a matter of "How much are you willing to spend to procure and launch these things?"
Quote from: Ben the Space Brit on 05/24/2016 09:53 amAs I understand it, the Eastern Range needs a couple of days to recycle its status after every launch. The question is 'what is the maximum possible production rate' combined with 'how long does a nominal pad flow (launch to launch) for the VAB and LC-39B take?"Other than that, it's just a matter of "How much are you willing to spend to procure and launch these things?"So the launch site and its equipment could easily handle 2 to 4 yearly launches (a dozen another matter I wager). As you say, it's the budget to build the rockets themselves in question then.
Did I miss the part where NASA has 2 or 3 VAB high bays dedicated to SLS, along with an MLP for each SLS vehicle being assembled, or assembled and waiting to launch? Because those might be considered as part of the launch site and its equipment.As it stands now, there is exactly one VAB high bay being fitted for SLS. And only one MLP. So the assembly of the second SLS cannot even begin until the first SLS is launched, and the MLP is reconditioned and rolled back to the VAB.If NASA ever needs to launch a series of SLS in sequence, more high bays will have to be fitted for SLS, and more MLPs will need to be built. This is certainly possible, but is not part of the current plan.Cheers!
Having payloads for 3 SLS launches per year would be even more interesting. What would they be, where would they be going and what would they cost?
The reason SLS production maxes out so early is that they reworked it to minimize cost in the context of the severe lack of anything to do that resulted directly from Obama cancelling the lunar surface mission.
It wouldn't cost all that much extra in the grand scheme of things to run SLS like Shuttle but with more sophisticated tooling.
Peak production could be a dozen cores per year, easy.
You'd need to pay for the plant upgrade, but that wouldn't break the bank by itself in the context of an actual agreed-on and funded exploration program.
Quote from: 93143 on 05/24/2016 10:00 pmThe reason SLS production maxes out so early is that they reworked it to minimize cost in the context of the severe lack of anything to do that resulted directly from Obama cancelling the lunar surface mission.At no time during the life of the SLS was there a lunar surface mission approved.
The tooling is already "sophisticated".
As to cost, we don't know what the cost drivers are because NASA has not released any cost data to the public or to Congress.
watching how reluctant Congress is in funding payloads and missions for the SLS
The plant modernization for SLS deliberately incorporated a severe reduction in maximum capacity as a cost-saving measure.
The driver for this decision was the combination of restricted out-year funding and anemic mission manifest proposed by the White House.
Characterizing SLS as a "rocket to nowhere" is ignoring the elephant in the room - the fact that lunar surface missions require only one additional hardware element to start and can happen as often as you like for quite a while without exhausting the possibilities.
Really, to some of us who have been paying attention since well before the Augustine Commission, it looks like the Obama administration is doing its best to make SLS look as useless and unaffordable as possible.
I'm using the ESD Integration numbers...
Normally Congress funds things that have been proposed to them by NASA/the Executive branch. They went way out on a limb to get SLS (and rescue Orion, which nobody had proposed cancelling before Obama did it)
...and considering that they've been having trouble just passing budgets...
...I don't think it's reasonable to expect much more out of them with Obama in the White House.
ARM was never a terribly attractive idea, and doesn't solve the mission manifest problem.
Scaling up isn't that simple; it can affect centre of mass (and thus the stability of the vehicle whilst thrusting or rotating). It can also affect heat generation. Generally, scaling-up turns out to be harder (and more expensive) than just designing a new spacecraft from scratch. In many ways, Orion (which was supposed to be just a scaled-up and modernised Apollo) is proof of that.
Yes but you're missing an essential point. The money is not available to develop and build 'flagship'-class missions like Cassini right now, no matter how large its propellent load. As I said in my previous post, there are limits to engineering. You can only put so many fuel tanks onto a probe bus before it becomes too sluggish to align its sensors properly. Fixing problems like this is another cost driver and it ultimately becomes an issue of having to redesign the whole vehicle from scratch because that's a cheaper solution.Simply put, you'd be better off designing a probe sized for SLS from scratch than spending millions (if not billions) on a fruitless effort to scale up an existing design.
I think that it should be possible to design even a 'Discovery'-class spacecraft that will only fit on SLS.
Quote from: Eerie on 05/27/2016 12:50 pmI think that it should be possible to design even a 'Discovery'-class spacecraft that will only fit on SLS.Mutually exclusive: 'Discovery'-class spacecraft and SLS.
Quote from: Jim on 05/27/2016 01:27 pmQuote from: Eerie on 05/27/2016 12:50 pmI think that it should be possible to design even a 'Discovery'-class spacecraft that will only fit on SLS.Mutually exclusive: 'Discovery'-class spacecraft and SLS.I'm talking about price.I mean, you could launch a 100 ton solid piece of iron on SLS, theoretically.
A Discovery class mission can be launched on a smaller rocket, so why add mass to use SLS?
Re: large payloads for SLS. How much more expensive could it be to take the design of a not super-heavy space craft, and just enlarge the fuel tanks until it's too large for everything but SLS? I dunno, imagine Cassini with an additional 20 tons of hydrazine. it could have many more years of service...
Quote from: 93143 on 05/27/2016 12:03 amReally, to some of us who have been paying attention since well before the Augustine Commission, it looks like the Obama administration is doing its best to make SLS look as useless and unaffordable as possible. The Obama administration? It's half the members of this site!
Quote from: RonM on 05/27/2016 01:53 pmA Discovery class mission can be launched on a smaller rocket, so why add mass to use SLS?To fabricate payloads for SLS. :-)
Quote from: wannamoonbase on 05/24/2016 08:53 pmHaving payloads for 3 SLS launches per year would be even more interesting. What would they be, where would they be going and what would they cost?You of all people ask that...The reason SLS production maxes out so early is that they reworked it to minimize cost in the context of the severe lack of anything to do that resulted directly from Obama cancelling the lunar surface mission. A lunar lander would only have to be developed once (~$10B for Altair, or much less (I'd hope) for Xeus) after which the cost per unit would depend on the flight rate.It wouldn't cost all that much extra in the grand scheme of things to run SLS like Shuttle but with more sophisticated tooling. Peak production could be a dozen cores per year, easy. You could launch half a dozen rockets a year for maybe a few billion dollars, possibly less. You'd need to pay for the plant upgrade, but that wouldn't break the bank by itself in the context of an actual agreed-on and funded exploration program.
Characterizing SLS as a "rocket to nowhere" is ignoring the elephant in the room - the fact that lunar surface missions require only one additional hardware element to start and can happen as often as you like for quite a while without exhausting the possibilities. And this was the plan before the FY2011 PBR, which SLS was a rejection of; the law makes it pretty clear that Congress still supported the VSE. Really, to some of us who have been paying attention since well before the Augustine Commission, it looks like the Obama administration is doing its best to make SLS look as useless and unaffordable as possible. Trying to turn it into as big a waste of money as possible, rather than either honestly trying to cancel it or honorably trying to make the best of it. And this "lack of need" talk plays right into their hands.
Quote from: llanitedave on 05/27/2016 03:40 pmQuote from: 93143 on 05/27/2016 12:03 amReally, to some of us who have been paying attention since well before the Augustine Commission, it looks like the Obama administration is doing its best to make SLS look as useless and unaffordable as possible. The Obama administration? It's half the members of this site!It was Congress that promised the SLS was needed, so why aren't they being held accountable?
Quote from: Coastal Ron on 05/27/2016 08:24 pmQuote from: llanitedave on 05/27/2016 03:40 pmQuote from: 93143 on 05/27/2016 12:03 amReally, to some of us who have been paying attention since well before the Augustine Commission, it looks like the Obama administration is doing its best to make SLS look as useless and unaffordable as possible. The Obama administration? It's half the members of this site!It was Congress that promised the SLS was needed, so why aren't they being held accountable?Congress is now directly funding SLS payloads because the administration won't plan for them. Their budget profile is not inconsistent with a yearly launch rate.2021-EM-22022- Europa Clipper2023- EM-3 with DSH2024- Europa LanderSome notes on this schedule. Congress directed the administration by law to give a profile of funding in order to get Europa ready to fly by 2022. There was a budget profile for Europa presented in the 2017 PBR. The house NASA budget has the 2017 amount quoted by NASA in the PBR with padding. Funding for a DSH starting in 2017 gives 6 years until the 2023, which I think is doable especially when some of the concepts are simply more pressurized volume which shouldn't be complicated. I am pretty sure that EM-2 slipping to 2023 was based on outyear planning based on PBR outyear funding profiles which are always lower for SLS and Orion than what they actually get. NASA was planning based on unrealistically low funding.
SLS and in fact most of existing LVs and people/organizations around them are an interesting target for social studies of organizations under paradigm shift.All kinds of bizarre psychological reactions are present.Lots of hilarity, such as ESA and ULA each designing a new LV which is *obsolete before it is even built*.This thread is an example of a bizarre psychological reaction - denial.SLS is dead, like a huge dinosaur with its tiny head chopped off. The huge body - meaning, all the people who spent years lobbying and pushing for this plan, the people employed in designing and building it, people who maintain the infrastructure on the Cape - is still "alive".Somewhere inside they know its all futile. SLS will be canceled, sooner or later.But they are far too invested into the project to allow this thought to fully form in their heads, much less to say it out loud. Some are "merely" unwilling to admit that they were wrong. Others would lose their job, for some this also means a failure as a manager.Politicians, as usual, don't even care that it's useless - what's important is that today money do flow to their districts, so eventual cancellation of SLS is unimportant (to them).
Quote from: gospacex on 06/03/2016 11:59 amSLS and in fact most of existing LVs and people/organizations around them are an interesting target for social studies of organizations under paradigm shift.All kinds of bizarre psychological reactions are present.Lots of hilarity, such as ESA and ULA each designing a new LV which is *obsolete before it is even built*.This thread is an example of a bizarre psychological reaction - denial.SLS is dead, like a huge dinosaur with its tiny head chopped off. The huge body - meaning, all the people who spent years lobbying and pushing for this plan, the people employed in designing and building it, people who maintain the infrastructure on the Cape - is still "alive".Somewhere inside they know its all futile. SLS will be canceled, sooner or later.But they are far too invested into the project to allow this thought to fully form in their heads, much less to say it out loud. Some are "merely" unwilling to admit that they were wrong. Others would lose their job, for some this also means a failure as a manager.Politicians, as usual, don't even care that it's useless - what's important is that today money do flow to their districts, so eventual cancellation of SLS is unimportant (to them).It's not clear, but are you saying you're not a fan of SLS? Let's keep these threads on the topic of the thread, not least when the above reads like you're insulting everyone who doesn't buy into your personal opinion.
Congress is now directly funding SLS payloads because the administration won't plan for them.
Their budget profile is not inconsistent with a yearly launch rate.2021-EM-22022- Europa Clipper2023- EM-3 with DSH2024- Europa Lander
Some notes on this schedule. Congress directed the administration by law to give a profile of funding in order to get Europa ready to fly by 2022.
Funding for a DSH starting in 2017 gives 6 years until the 2023, which I think is doable especially when some of the concepts are simply more pressurized volume which shouldn't be complicated.
I am pretty sure that EM-2 slipping to 2023 was based on outyear planning based on PBR outyear funding profiles which are always lower for SLS and Orion than what they actually get. NASA was planning based on unrealistically low funding.
From what I can see the Europa Clipper and Europa Lander are part of the same mission now called the Europa Multiple-Flyby Mission.
Possible verging on probable, but then there is the entirely separate issue of sparse funds for any major probes whatsoever. Discover is a shadow of what it was intended to be partially because of SLS eating up budget
I don't think this is even remotely accurate, though I would like Blackstar to clarify. But as I understand it, the SLS/Orion budget is taken from a different pool than those used for Discovery missions. The squeeze you are seeing on Discovery missions has more to do with JWST than anything related to SLS/Orion.SLS/Orion is basically using the budget we used for STS.
The SLS manifest is only apparently empty because the HSF and Planetary communities are cautiously awaiting permission; again citing Europa, that mission is on the list. An Orion and Europa flying in the same year will be a grand way to showcase SLS' versatility. Even assuming a new President wants to gut the program, they will be extremely hesitant to avoid upsetting both the public and Congress - kicking NASA is like kicking a puppy. There will be missions to fly on SLS alongside Orion, even at a slow pace.
the budget we used for STS.
Not really. Orion has no place to go with a hab. And Europe is still EELV compatible.
So, to summarise: we have the Musk F9H and BFR, and the Bezos BFRs (plural), all sort-of-probably self-financed and trundling along nicely and with *zero* need to assuage the politicians, and then we have SLS, slave to pork and with few obvious payloads.In short, I wish the US Government would finance payloads, and get out of the launch business.
Quote from: Bob Shaw on 09/17/2016 12:02 amSo, to summarise: we have the Musk F9H and BFR, and the Bezos BFRs (plural), all sort-of-probably self-financed and trundling along nicely and with *zero* need to assuage the politicians, and then we have SLS, slave to pork and with few obvious payloads.In short, I wish the US Government would finance payloads, and get out of the launch business.It is slowly heading in that direction it appears. SpaceX and Blue Origin and their respective rockets are still in the fledgling phase and yet to fly; the SLS will probably see some use before it gets traded out for a commercial equivalent. Most likely, if anything, we will initially see NASA finally create a blend of plans that utilize more commercial rockets supplementing SLS and Orion. That I think will be the first step in a good direction, but again I believe the SLS will have some use.
Quote from: redliox on 09/17/2016 01:48 amQuote from: Bob Shaw on 09/17/2016 12:02 amSo, to summarise: we have the Musk F9H and BFR, and the Bezos BFRs (plural), all sort-of-probably self-financed and trundling along nicely and with *zero* need to assuage the politicians, and then we have SLS, slave to pork and with few obvious payloads.In short, I wish the US Government would finance payloads, and get out of the launch business.It is slowly heading in that direction it appears. SpaceX and Blue Origin and their respective rockets are still in the fledgling phase and yet to fly; the SLS will probably see some use before it gets traded out for a commercial equivalent. Most likely, if anything, we will initially see NASA finally create a blend of plans that utilize more commercial rockets supplementing SLS and Orion. That I think will be the first step in a good direction, but again I believe the SLS will have some use.I would advocate/prefer ditching the SLS solids, keeping the corestage but moving to Commercially-supplied liquid boosters; reusable or not.
Quote from: MATTBLAK on 09/17/2016 02:12 amQuote from: redliox on 09/17/2016 01:48 amQuote from: Bob Shaw on 09/17/2016 12:02 amI would advocate/prefer ditching the SLS solids, keeping the corestage but moving to Commercially-supplied liquid boosters; reusable or not.I agree in general, although I think the biggest reason why the solids are favored is that they don't require plumbing and cryogenic needs. The change from Block 1 to Block 1B is going to cause plenty of grief with ground hardware just to move the umbilicals higher to serve the EUS as an example. Ultimately it will come down to what companies offer NASA as an advanced booster.
Quote from: redliox on 09/17/2016 01:48 amQuote from: Bob Shaw on 09/17/2016 12:02 amI would advocate/prefer ditching the SLS solids, keeping the corestage but moving to Commercially-supplied liquid boosters; reusable or not.
Quote from: Bob Shaw on 09/17/2016 12:02 am
7 meters is probably too big - would require either a new launchpad or major alterations to existing ones. Perhaps 5.4 meter boosters with as many BE-3 or other commercially supplied engines as will fit.
This discussion makes me wonder about the existing stocks of casings for SRBs. I think there are enough for 10 flights. If nothing changes, then at one a year, SLS can launch until 2028. It will be interesting to see if Congress authorizes (additional) money to develop new SRBs in about 2022, because I am sure it will take that long to develop them.New boosters were proposed for Shuttle, but did not materialize.Of course, I probably missed if there is any money currently allocated to advanced solid boosters nd when they expect them to come on line.
Courtesy of the 'Minimal Architecture for Human Journeys to Mars' thread and the Price-Baker presentation. Until Martian surface missions happen, we may see an average of 1 SLS yearly. Some of the dates likely will be tweaked, but the presentation itself is dated for September 14, 2016 so it is as current as can be expected. I included the presentation itself as well, which focuses on visiting Phobos and then Mars.