Author Topic: SLS General Discussion Thread 2  (Read 226074 times)

Offline Coastal Ron

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Re: SLS General Discussion Thread 2
« Reply #440 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.

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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.

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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.

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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...
If we don't continuously lower the cost to access space, how are we ever going to afford to expand humanity out into space?

Offline notsorandom

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Re: SLS General Discussion Thread 2
« Reply #441 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.

Offline Coastal Ron

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Re: SLS General Discussion Thread 2
« Reply #442 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.

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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.

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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.

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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".

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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.

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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.

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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...
If we don't continuously lower the cost to access space, how are we ever going to afford to expand humanity out into space?

Offline spacenut

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Re: SLS General Discussion Thread 2
« Reply #443 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. 
 

Offline edkyle99

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Re: SLS General Discussion Thread 2
« Reply #444 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
« Last Edit: 05/18/2016 03:16 AM by edkyle99 »

Offline spacenut

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Re: SLS General Discussion Thread 2
« Reply #445 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. 
« Last Edit: 05/18/2016 01:45 PM by spacenut »

Online Ben the Space Brit

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Re: SLS General Discussion Thread 2
« Reply #446 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.
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Offline ncb1397

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Re: SLS General Discussion Thread 2
« Reply #447 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.

Offline edkyle99

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Re: SLS General Discussion Thread 2
« Reply #448 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
« Last Edit: 05/18/2016 07:34 PM by edkyle99 »

Offline Coastal Ron

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Re: SLS General Discussion Thread 2
« Reply #449 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.

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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.

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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.
If we don't continuously lower the cost to access space, how are we ever going to afford to expand humanity out into space?

Offline A_M_Swallow

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Re: SLS General Discussion Thread 2
« Reply #450 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.

Online QuantumG

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Re: SLS General Discussion Thread 2
« Reply #451 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.

Jeff Bezos has billions to spend on rockets and can go at whatever pace he likes! Wow! What pace is he going at? Well... have you heard of Zeno's paradox?

Offline A_M_Swallow

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Re: SLS General Discussion Thread 2
« Reply #452 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

Offline spacenut

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Re: SLS General Discussion Thread 2
« Reply #453 on: 05/19/2016 02:34 AM »
How much per launch would the SLS cost if they launched say 4 per year? 

Offline Proponent

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Re: SLS General Discussion Thread 2
« Reply #454 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, 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: Orion/SLS does not come out looking good (discussion here and following).

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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.

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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.  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.
« Last Edit: 05/19/2016 08:03 AM by Proponent »

Online Ben the Space Brit

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Re: SLS General Discussion Thread 2
« Reply #455 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.
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Offline spacenut

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Re: SLS General Discussion Thread 2
« Reply #456 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. 

Offline notsorandom

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Re: SLS General Discussion Thread 2
« Reply #457 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.

Offline spacenut

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Re: SLS General Discussion Thread 2
« Reply #458 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. 

Offline Graham

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Re: SLS General Discussion Thread 2
« Reply #459 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.
I have loved the stars too fondly to be fearful of the night
- Sarah Williams

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