How many flights for the SLS, ever?

[Endeavour_01]

I voted for 21 or more flights for more or less the same reasons as marcus79. A couple of my own thoughts:

In the long run (i.e. 30 year program) the cost of 21 or more flights of SLS/Orion will come out roughly the same as the shuttle. Since NASA flew the shuttle successfully for 30 years I think SLS/Orion can make it. They are not perfect by any stretch of the imagination but neither was the shuttle. SLS has a second to none payload capacity and the ability to launch human missions farther than we have gone in over 40 years (not to mention the numerous unmanned projects it can support). Just as young and old embraced the shuttle I believe the public will embrace SLS/Orion.

[Ben the Space Brit]

@Endeavour_01,

Of course, the Shuttle flew multiple times a year (six on average, IIRC). SLS flights will be far less frequent and Orion launches even less frequent still. I, personally, suspect that a year when there is one or two cargo and one Orion launch in the same year will be considered a 'high launch rate'.

In the end, the mission is everything. If NASA can catch the public's imagination with a destination and a mission, then all sins will be forgiven. Otherwise it will not have widespread support and will be permanently at risk of being defunded. The Shuttle got away with place-holder missions because there was nothing else in terms of US-indigenous HSF. However, commercial crew launchers and possibly even commercial LEO destinations potentially will undermine that line of defence for SLS.

[The Amazing Catstronaut]

Considering the possibility that the SLS may one day cost as much as an STS mission, adjusted for inflation, I'm docking my optimism to 5 flights.

The BFR will eventually knock SLS out of commission; ridiculously higher hypothetical payload, significantly lower launch costs, significantly less things to go wrong with it, easier for the crew to abort.

[Hog]

Considering the possibility that the SLS may one day cost as much as an STS mission, adjusted for inflation, I'm docking my optimism to 5 flights.

It will require 2 SLS launches to be on equal comparison of a single STS launch, considering STS's unique capability. Safety is the primary driver to seperate crew and cargo.

[Steven Pietrobon]

If the cargo is to be used by the crew, that rule doesn't apply. For example, a (crewed) Lunar Lander or Orbital Module. The rule is for non-crew related payloads, like commercial communication satellites.

[geza]

My understanding was that separation of crew and cargo is justified because it is easier to make a smaller rocket safe. This idea manifested in the 1.5 launch scenario of Constellation, when lander and upper stage (both crew-related) was separated from the crew during launch. Did I miss something?

[owais.usmani]

21 and counting.

US has the economy to sustain SLS, even when they don't need it.

[kbd512]

I vote for 4 launches.

If I'm not mistaken, they have 15 RS-25's and enough parts to make another RS-25, so that gives them enough hardware for 4 launches.  I can't recall exactly how many SRM parts were stated as being available, but I think there were also enough parts for at least four sets.

SLS is just bizarre to me.  I like our manned space program and I think it's a national imperative for a nation that purports to be a leader in technological innovation, assuming we're doing more than paying lip service to the idea.  I don't fault NASA for the stupidity of Congress, but I do fault them for going along with it.

I'll preface my following remarks.  I'm not a rocket scientist and I don't play one on TV.  It seems to me as if the question of how to get to the moon has already been asked and answered.  I'll be speechless if SLS ever attains the lift capability it's supposed to or is less expensive per flight than STS.

I understand why only a limited number of Saturn V rockets were flown, but I also think that every aspect of how we design, develop, manufacture, and test has been markedly improved since the 1960's.  The engineers and rocket scientists of today ought to be able to do better, given so many technological advantages over those who came before them.

Why dump expensive reusable flight hardware into the ocean instead of using it for what it was designed for?  Was it absolutely impossible, in the 30 years that the STS program was in operation, to design and build robots to perform some of the labor intensive tasks that caused each STS mission to cost so much?  A robot that drives around on Mars was worth the effort, but not a tile laying and inspecting robot?

With the amount of money NASA expended on various launch initiatives since the STS program was in operation, every major component of the Saturn V rocket could have been reconstructed and improved to restore the lift capability.

[quanthasaquality]

voted 21+

The SLS surprises some people in Congress, and myself, by going only moderately over budget, and behind schedule, unlike many light rail lines, the National Ignition Facility, the James Webb Telescope, ITER, and many other government programs. Sticking with what you know has its advantages, like the rs-25, 3.7 meter ATK solid rocket motors, and 8.4 meter diameter hydrogen tanks. The SLS, with DUUS, and Ukrainian Tsyklon 4 upper stage, proves to be a low cost development way of putting stuff on the moon, at a a moderate price.

Congress, pleased that NASA delivered, at a less than a very high price, ups spending, to use the SLS's lower incremental cost, and a moon base with ISRU is the result.

I wouldn't bet money on it happening.

[AegeanBlue]

Voted 6-10

The number of flights depends entirely on the success of the Falcon Heavy and its successors. There is no real commercial reason for a launch vehicle the size of the SLS, even at its most limited version and there is limited market even for the Falcon Heavy. The Delta IV Heavy has launched a very limited number of NRO birds, it seems that there is a series of spy sats that require it but beyond that no market. Elon Musk is known to create not only a technically good product but also a market out of thin air, think of Tesla succeeding where the EV-1 failed. The Falcon Heavy will make it to space, though unless SpaceX can create the sort of adapter that allows 5+ full sized satellites to be deployed in GTO it might find itself out of a market. Then comes the issue of how can you get 5 satellites ready at the same time, think of Ariane's chronic delays issues with just two. It will take a long time for a market for the MCT to appear, especially since it requires multiple Raptors, I do not see the kinks worked out before the middle of the next decade. If the MCT is successful, man rated and NASA has a budget to put cargo on it, it will replace SLS around the end of the 2020s. Thus I expect EM-1, EM-2, Europa Clipper, Habital at Lunar DRO (I do not see ARM happening) if that requires SLS (FH might do fine with an inflatable module) and a couple of missions there (and down to the moon?) until FH+ or MCT of BFR becomes proficient and cheap enough to replace SLS.

[Vahe231991]

I know that no one has posted on this thread since 2015, but the Falcon Heavy has successfully launched five times, and even though the initial tentative timetable for the launch of the SLS was stymied by budget constraints, the first launch of the SLS last November was a success, and construction of hardware for the SLS rockets to be used in the Artemis 2 and 3 missions is now well-advanced. SpaceX and NASA are sharing the burden of all planned Artemis missions beginning with Artemis 3 in terms of cost, so the development of the Starship HLS ensures that for the first time in the history of US space exploration, NASA will be partnering with a private company to fund an extraterrestrial human spaceflight. The Artemis 9, 10, and 11 missions will be carried out by the SLS Block 2 variant.

[jstrotha0975]

I chose 4-5 flights. It's just not sustainable and when Starship is fully operational SLS won't be needed any more. Many parts will end up in museums.

[john smith 19]

I chose 4-5 flights. It's just not sustainable and when Starship is fully operational SLS won't be needed any more. Many parts will end up in museums.

I think in 2015 they were expecting BFR/MCT/SS to be flying by 2019?2020?

It's 2023 and the future still hasn't turned up yet. 

[Jim]

I know that no one has posted on this thread since 2015, but the Falcon Heavy has successfully launched five times, and even though the initial tentative timetable for the launch of the SLS was stymied by budget constraints, the first launch of the SLS last November was a success, and construction of hardware for the SLS rockets to be used in the Artemis 2 and 3 missions is now well-advanced. SpaceX and NASA are sharing the burden of all planned Artemis missions beginning with Artemis 3 in terms of cost, so the development of the Starship HLS ensures that for the first time in the history of US space exploration, NASA will be partnering with a private company to fund an extraterrestrial human spaceflight. The Artemis 9, 10, and 11 missions will be carried out by the SLS Block 2 variant.

No.  Falcon Heavy has nothing to do with SLS.   SpaceX is not cost sharing with NASA.  NASA will be paying for all costs associated with the lander.

[Eric Hedman]

All those years ago I voted 3.  I am now in the 6 to 10 range.  I don't see how SLS keeps going long after Starship is flying.

[Harry Cover]

All those years ago I voted 3.  I am now in the 6 to 10 range.  I don't see how SLS keeps going long after Starship is flying.

You should not underestimate the mighty power of Pork Barrel Congress ! Don't forget Ares V / SLS have persisted since January 2004... almost 20 years ago !

[etudiant]

We live in a world of representative government.
Blaming 'pork barrel' for political efforts to defend ones constituency is misguided, imho.
All Elon needs to do is to set up a post Star Ship development center in Huntsville.
I'd bet he'll be overrun with talent.
The byproduct would be a sharply increased willingness by NASA to consider Artemis alternatives.

[VSECOTSPE]

and even though the initial tentative timetable for the launch of the SLS was stymied by budget constraints

No budget constraints.  SLS has always received more appropriations than requested.

[Coastal Ron]

I know that no one has posted on this thread since 2015, but the Falcon Heavy has successfully launched five times, and even though the initial tentative timetable for the launch of the SLS was stymied by budget constraints...

A false statement, since the SLS program has consistently received more than the Obama, Trump, and Biden Administrations have requested. And despite that, it STILL has not met the Congressional mandate of being "operational" by the end of 2016. So far all we have is one test flight, without humans.

...the first launch of the SLS last November was a success, and construction of hardware for the SLS rockets to be used in the Artemis 2 and 3 missions is now well-advanced. ... The Artemis 9, 10, and 11 missions will be carried out by the SLS Block 2 variant.

None of that has anything to do with how many flights of the SLS will actually happen. For instance, it doesn't matter if there is hardware already built, because Congress can cancel a program regardless how much work in progress there is. And the SLS is a political program that can be cancelled without too much advanced notice, just like the Constellation program was cancelled.

As it stands, it is only because of Elon Musk and the Starship program that NASA has a chance of landing humans on the Moon this decade, because if SpaceX was not already in development of the Starship, no other company or coalition of companies could have designed, built, tested, and made operational, a lunar lander this decade. Which means without the SpaceX Starship the SLS would have had little to do once Orion testing was complete.

So ironically, it is only because of the Starship that the SLS has something to do this decade, but it may also be the Starship that finally gets Congress to stop wasting so much money on the SLS. Time will tell...

[kraisee]

and even though the initial tentative timetable for the launch of the SLS was stymied by budget constraints

No budget constraints.  SLS has always received more appropriations than requested.

Yes, but most of the political cabal that supported SLS have moved on. The big powerhouse in this, Shelby, just retired. Hutchison and Mikulski left a few years ago and while Nelson now runs NASA, he doesn't make the political decisions any longer, they get given to him now.

There are a few (comparatively) new faces emerging in the DC scene who are still supporting SLS, but they don't have the clout of the aforementioned group, NASA isn't such a high priority for them and being younger and with less authority, they aren't owed as many favors by others.

I personally think that as we start to see regular, low-cost Starship missions happening from multiple launch sites around the country, the next $2 billion SLS launch will see public opinion shift because nobody will be able to justify using SLS at that price - it will just look silly. And political support will completely evaporate at that point.

I therefore predict Artemis 3 will be the last to fly. Everything after that is a future museum piece.

The new Artemis Moon-focused Program will still continue without SLS though. Probably using a combination of SpaceX and Blue Origin launch systems at its core.

If I were one of the newer crowd of political figures involved, instead of supporting SLS ad-infinitum, I'd be spending my energies asking Elon when he's going to open some sort of facility in my state, building batteries, cars, robots, satellites, rockets, TBM's, Hyperloops or whatever.

Ross.