How many flights for the SLS, ever?

[Zed_Noir]

I voted for one SLS flight. It is the sight of regular Falcon Heavy flights from LC-39A after 2016 that will make the SLS moot. Heck even an expandable FH is cheaper than a Delta IV Heavy, never mind the SLS.

[Lars_J]

I voted 1 flight. The funding reality and lack of missions will catch up to it, and cause it to be cancelled after 1 flight. In particular when commercial alternatives (even if not as capable) highlight cost differences.

[strangequark]

I voted 2. Does not appear to be the political will to fund the kind of missions that would require the payload. After this administration, focus moves back to Lunar, which doesn't really mandate a 130-tonne launcher.

If you will forgive a morbid point, Senator Shelby is 80, so a standard actuarial table gives him a mean of 8 more years. The same holds for Senator Orrin Hatch of Utah, who is not on Appropriations, but is the 2nd most senior Senator. If I am right about the missions staying sparse, then around 2022 SLS will not have demonstrated a compelling raison d'etre, and Alabama and Utah will no longer have such outsized political power. Barbara Boxer (D-CA) will likely take Dianne Feinstein's (D-CA) slot on Appropriations. She would be 5th most senior member of the committee, and of the other 4, only Barbara Mikulski (D-MD) and Thad Cochran (R-MS) are from states with a NASA center. Senator Cochran won't care about SLS, so long as engines get tested at Stennis, and Senator Mikulski will be focused on science payloads, with some sympathies for Wallops/MARS. In short, I think the center of gravity moves to favor the "new space" players.

TL;DR: SLS probably loses its most powerful supporter right around 2nd launch. SLS dies when Alabama no longer has a ranking seat on Senate Appropriations.

[Space Ghost 1962]

It is doubtful a manned Orion will fly on SLS - on the borderline. Voted 2.

If even the enormous stretch of the asteroid snatch mission, which is one of the most spend thrift HSF BEO missions in the history of the world can't get bucks, then any more Buck Rodger missions are even more far fetched,

I've stopped commenting on SLS because ... there's no point in talking to those who won't hear. It's meant to always be an indefinite threat ... if it ever gets realized, it can't be a threat, so it stops. Strangequark does an excellent job on the details.

You can tell as we get closer to first flight by the lack of progress on missions/engines/other longer term collateral. Dead man walking.

Dunno what comes after that. It may be that HSF transitions to private launch services for contracted missions on government sourced vehicles/mission modules, where they threaten to bring SLS back occasionally but fall back to commercial launch services to take up the slack given capacity. Or fades from view.

[Lar]

Reminder, one post per member, and no debate. Thanks. (so far this thread is going fairly well. except for someone who violated that, thank you several members for prompt mod reports)

[anonymous1138]

Thinking this one through, it's hard to see where SLS is going. There is one development flight, then a second flight. Then ... ? I see at most 3 flights (very expensive flights), driven by what I perceive to be the answers to the questions below. The questions I ask myself - and maybe there are answers to these that I am unaware of - are:

1) How much does SLS cost to own per year even if there are no flights?
2) How slow is the production line expected to be, and can it ever sit idle, or will we keep building and storing SLS vehicles until they are needed?
3) At such a slow rate, what is the total cost per flight expected to be, and the resulting cost per pound? What if you include development costs that would not have been needed had there had instead been a competition to develop and provide specified launch services?
4) If the SLS is expected to take us to Mars, when will we start funding the development of landers, habitats, etc., how much will those cost, and when will they be ready for flight?

These questions didn't just pop up recently. They've been getting asked since SLS was announced. Taxpayers deserve an explanation. When SLS is cancelled or superseded, send Sen. Shelby the bill.

[Ben the Space Brit]

My gut feeling is four. They'll fly out their supply of SSMEs and RSRM-Vs but I've got a feeling that funding for RS-25e and Future Booster will be cut, effectively cancelling the program after EM-3 in 2023-ish.

[fast]

I say 1. Same story as Ares.

[bad_astra]

4-5. I suspect we are on the verge of commercial fusion power, which will change quite a bit more than spaceflight but obviously this as well. The age of the chemical superbooster might be over in two decades. I suspect two generations from now they'll regard them as we think of pre-war Zeppelins now, giant quaint ideas that went around the obvious solutions.

[rayleighscatter]

21+

Shuttle took nearly 15 years to start doing what it was built for, but the US kept flying it for those first 15 years anyway. So long as it can get one flight under its belt no one will take the political risk of cancelling the US space program. And after that it will only take one president or congress who, for whatever reason, wants to do something showy and start a lunar or martian campaign.

It'll be NASA's B-52, people might want to get rid of it but no one will want to pay to replace it.

[bob the martian]

If it flies at all (and there's a non-zero chance that it won't), I don't expect more than 2 to prove out the hardware.  I do not expect any manned flights.   

It has no mission other than keeping the legacy spaceflight manufacturing sector employed.  There's no comprehensive program of deep space exploration for it to support, and one isn't going to magically spring up to justify it.  At best there would be a couple of one-offs like the asteroid capture mission, but nothing that's part of a larger goal.

Once CC starts flying people, that will be the end of it.  And that's assuming we'll still have a reason to fly people anywhere; the ISS isn't going to last forever, and I do not foresee us replacing it.

[sdsds]

STS-114 through STS-135 was 22 Shuttle flights after Columbia. SLS will be about that successful. So I'm near the edge but going with "21 or more."

[Planetaryduality]

I guessed 4 or 5. They've built the tooling and upgraded the test and ground facilities, I can't see them cancelling the program before they use up the available hardware. I would like more, but realistically that's what I'm expecting.

[Comga]

What strangequark said
and Jim (in so many less words) 

[Robert Thompson]

none

[robertross]

I voted 6-10, mainly based on how I see the crystal ball play out.

What strangequark said is quite true, but I feel that there will be a bunch of hardware available to carry out a number of launches until they can close down the lines.

This will suffer the same fate as the Saturn V / Apollo program, except this time it will not reach the ultimate goal of Mars (whereas the goal of Apollo was acheived with landing a man on the moon). It's quite sad to think this will likely be the case for SLS. However, it's the fact that there were, like always, political buttons pushing things in certain directions.

I still feel they wouldn't need anything larger than the 70mt version (and still say the 'metric' notation for mass is another issue in the scheme of things).

And I am using SLS in the whole program sense, not just the final 130mt monster rocket.
I think NASA is smart enough to avoid a launch failure, but a failure in controlling costs, and in program management, could be the ultimate undoing of this rocket & program.

But on the bright side, NASA would likely have a commercial alternative already flying, or ready to fly, in SpaceX's Falcon Heavy, by the time the UNite States realizes the mistake it made (yet again) in abandoning another launch vehicle design.

[wannamoonbase]

At 1 launch every two years it will take 40 years to get to 20.

There were years where the shuttle flew 7-8 times. It should be easier to launch SLS.  Building payloads for the top will be the challenge, anything that big will cost a lot unless it's a repeatable payload like a cargo container, LEM etc.

If NASA ever got a clear mandate, such as building a moon base that has the goal of developing abilities to be a net exporter! Then SLS could have a big future.  Need a president with some vision for that to happen.

At least the hardware will be ready but it needs something to do.  No one can predict beyond the next few years, but NASA track record on new vehicles in the last 25 years is 0.000 to date.

[darkenfast]

One flight.  A majority of U.S. voters do not care enough about spaceflight to continue spending on this.

[KelvinZero]

I voted 2, Its my best guess but I don't put any value on my own opinion here, I just wanted to see the poll.

I would like to see a VSE-like lunar goal, but a long life for the SLS would be sort of sad because I think it would mean the exciting possibilities (eg commercial HSF, depots, SEP, F9R) did not pan out for whatever reason. They might exist in some form but not sufficient to cause any sort of paradigm shift if we are still running SLS 20 years later.

[Mark S]

I'm going all in with 21+ flights of SLS, for a number of reasons. Generally because SLS is a long-term investment and will be a long-term workhorse. But specifically:

1) Once it's operational, NASA will find many more uses for it than they will currently admit.
2) All of the money invested in SLS's development will motivate politicians to continue to vote for future funding.
3) Nothing in SLS's class is currently in development.
4) Thirty years of Shuttle history show that the US is willing to pay for a space program, even one that's not going BLEO.
5) Like hard disk space and CPU cycles, any increase in capacity will eventually be used, and sooner than you think.
6) America supports its space program because it is a source of national pride.
7) There will be a discovery or development that will turn our eyes upward and outward again. As a nation, not just us space nerds. I don't know what it will be, but I know that there will be one. It is inevitable.

Some will see this as overly optimistic, just as I see those who espouse "one and done" or "three and out" as overly pessimistic. It is true that NASA failed to replace Shuttle with new launch systems repeatedly, but that was always with an operational Shuttle fleet. We no longer have that. We need a Shuttle replacement, and SLS will be that, and more.

Now we have EFT-1 lined up for December this year (four months away), and EM-1 looking good for 2018. So yes, SLS is going to fly. And it's going to keep flying for many years to come. Until we need something even bigger.

Cheers!

Edit: I can't believe that at the time of this edit (Sunday evening), almost 60% (102/173) of those voting don't expect SLS to even use up the 16 SSMEs on hand. Now that's depressing, seeing as it comes from those who are interested enough in spaceflight to frequent this forum.