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#26 2014-01-12 22:42:25

SpaceNut
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From: New Hampshire
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Re: The SLS: too expensive for exploration?

NASA Administrator Bolden and Senator Vitter See Space Launch System Progress in New Orleans

NASA is developing the SLS and Orion spacecraft to provide an entirely new capability for human exploration. They will expand human presence beyond low-Earth orbit and enable new missions of exploration in the solar system, including to an asteroid and Mars.

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#27 2014-01-19 13:28:06

SpaceNut
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Re: The SLS: too expensive for exploration?

Nasa Prepares Framework for Space Launch System Engine Test

The SLS will have four RS-25 engines -- the same type which powered the space shuttle -- to power its core stage. Each engine is designed to provide 530,000 pounds of thrust.

The testing of the engines is due to begin this summer at NASA's Stennis Space Center in Mississippi. A test platform is being prepared for the installation of the first RS-25 engine arriving in May ahead of a hot-fire test in July.

So what really is being tested since this is an already fully tested engine?

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#28 2014-01-19 14:04:17

RobertDyck
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From: Winnipeg, Canada
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Re: The SLS: too expensive for exploration?

Excellent point. The J-2X is a new engine, so that requires testing. The SLS core stage, as a whole stage, will require testing. It has to be fired in a static test stand. But why test a separate Space Shuttle Main Engine? This sounds like make-work.

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#29 2014-01-20 09:37:58

GW Johnson
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From: McGregor, Texas USA
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Posts: 5,423
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Re: The SLS: too expensive for exploration?

Re-test the SSME?  Make-work?  Should not be surprising. 

Government agencies follow the rules totally exclusive to common sense.  They try (but always fail) to cover every possibility in the rulebooks they write.  Except that is not humanly possible.  The bigger the agency,  the more rigidified it gets.  NASA is a giant these days.  Wasn't in 1960. 

Private entities fall victim to the same kind of thinking,  too.  It's simply a function of size:  the bigger they are,  the more they tend to rigidify into nonthinking rulebook followers.  It's something inherent in human group behavior.

I think that's why the smaller outfits are generally doing the better,  more exciting work. 

GW


GW Johnson
McGregor,  Texas

"There is nothing as expensive as a dead crew,  especially one dead from a bad management decision"

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#30 2014-04-03 03:15:09

Quaoar
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Re: The SLS: too expensive for exploration?

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#31 2014-04-03 09:22:47

GW Johnson
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From: McGregor, Texas USA
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Posts: 5,423
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Re: The SLS: too expensive for exploration?

Hi Quaoar:

Looking at Parkinson's Law vs Parkinson's Disease,  I think the law actually does more damage to humanity.  The disease is merely fatal. 

One law I have noticed is that bureaucratic arrogance is usually inversely proportional to the level of demonstrated bureaucratic competence.

Another might be the "fourth law of thermodynamics":  HA >>> H    for which H is the number of horses,  and HA is the number of horses' asses. 

I know it's too late for April Fool's jokes,  but these,  while funny,  aren't really jokes.

Still,  I laugh to keep from crying!

GW


GW Johnson
McGregor,  Texas

"There is nothing as expensive as a dead crew,  especially one dead from a bad management decision"

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#32 2014-04-04 04:02:11

Glandu
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From: France
Registered: 2011-11-23
Posts: 106

Re: The SLS: too expensive for exploration?

At my current mission(I'm a consultant & frequantly changes customers), we are dead on it. things that could be done in 2 days are done in 2 weeks because there is budget for 2 weeks.

Where I was previously, it was the reverse : We had work for 12, we were 9, & 5 had to leave on budgetary grounds.

The worse is when it happens whitin the same team. In 2001, I was part of a team working on some Euro-related project. I was on the interface sub-team. We had finished in July 2001. I then played on internet until November. In the meantime, the batch sub-team was overloaded with problems, made countless hours, and I was not allowed to help them.

I love EXCEL as a tool, but when in wrong hands, it has absolute awful effects. There is some kind of estimation, some kind of plan, unaccurate because most things are unknown yet, and suddenly, some suit approves it, and it gets carved in stone. It is suddenly forbidden to change it. It is more sacred than the Bible. I've seen numerous projects fail of this disease.

The worst was a forecasted overhaul of customers management in a Paris-based mobile phone company. Budget was 60 people during 18 months. 35 people for designing the solution, & 25 to prepare the migration of data(includng 12 developers of an obscure, unpractical language, several testers including me, a few technical & functional experts, a SAP expert directly imported from Brazil, and a few managers). My first day of tester, I noticed a few mistakes in the spec. I then learned that the spec had been approved, and could not be changed - or corrected. Therefore, I could not validate the project : either it would work - but not according to specs - or it would respect the specs - but not work.

I also noticed the old system was all built on MVS-COBOL. After reading the specs, I was pretty sure I could do the migration alone in MVS/COBOL in less than 6 months. But the brass needed a big project to shine on their resume - and therefore choose a technical path that implied a big-sized project. I had the luck to be able to run away, but learned that 6 years later, the project had not done any progress. The whole brass had been fired, but new managers still could not make it work.

I have no reason to think the NASA works another way, unfortunately. Power struggles usually cloud everything, including technical sanity or financial efficiency.


[i]"I promise not to exclude from consideration any idea based on its source, but to consider ideas across schools and heritages in order to find the ones that best suit the current situation."[/i] (Alistair Cockburn, Oath of Non-Allegiance)

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#33 2014-04-04 19:07:17

SpaceNut
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Re: The SLS: too expensive for exploration?

Oh, really off topic now....

We have said that the initial design, per flight costs are to high and that is true; since we are talking about a government operation that is heavily unionized as well when we compare space x or others to how business is run.

Nasa runs R & D to the max without any consideration towards what the next flight of a design might really be for a business which needs to make a profit by keeping construction costs down.

So what could a Space X do with a design such as they have with the Falcon product line create to make large payloads to orbit possible? That does not mean continue to gang first stages side by side either...

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#34 2014-04-05 10:12:46

GW Johnson
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From: McGregor, Texas USA
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Re: The SLS: too expensive for exploration?

Atlas-5/lots of strap-ons carries 20-25 tons to LEO for near $2500/pound.  Delta-4/lots of strap-ons carries about 20 tons for about the same price.  Falcon-9 without re-use carries 13 (or maybe more) tons to LEO for about the same $2500/pound.  I think the numbers for Ariane and the others are close to the same.  That's where the commercial launch rocket business has gotten to.

Falcon-Heavy is supposed to fly this year.  It is said to be capable of 53 tons to LEO,  at a unit price very near $1000/pound. 

Now,  if one plots those unit price vs payload size data and extrapolates the trend,  something in the 100-ton class out to be around $500/pound.  Now,  look up projected prices for NASA's 100-ton class SLS,  and see unit prices at or above $2000/pound.  That's at least 4 times too high.  The Titan-4 was never used for commercial use,  and its unit price was also factor 4 too high,  above that plotted trend.

I think a 100-ton class rocket should be a cheaper unit price than what we have,  based on that commercial price trend.  The commercial launch sector is very likely to produce one,  once there is a commercial demand for 100-ton payloads.  But,  that won't be any time soon,  as there is no need for one that big.  Yet.

I don't think NASA's SLS will ever be as "cheap" as they claim it will,  much less as cheap as it should be.  NASA is infamous for cost overruns.  They know nothing about competition or controlling costs by looking at what fundamentally causes costs:  complicated designs that require logistical support "tails" the size of a major city for every launch.   There's no "savior" there in SLS.

My advice to all space enthusiasts would be to use the commercial rockets that we have,  and build what we want in LEO,  from payloads that we can launch with those rockets.  We already know assembly-by-docking works,  that's how we built ISS. 

ISS was expensive because the launcher (shuttle) was so expensive,  not because of the docked-module construction approach.  Shuttle was $1.5B per launch,  carrying at most 15 tons to the ISS orbit,  maybe 20 tons to less-inclined LEO.  ISS built today with commercial launchers would be factor 10-to-100 cheaper that what we did spend before.

Rule-of-thumb:  your direct launch expenses should be on the order of 20% of your total program cost.  You do that by using existing technologies and hardware to the greatest extent possible to accomplish your mission.  Technology development is a separate program,  do not do that in your program,  if your aim is to actually fly.  The best-known example is X-30/NASP.  It could not fly without scramjet technology,  which then still required development.  It still does today,  the X-51 flights notwithstanding. 

GW

Last edited by GW Johnson (2014-04-05 10:22:07)


GW Johnson
McGregor,  Texas

"There is nothing as expensive as a dead crew,  especially one dead from a bad management decision"

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#35 2014-05-18 19:10:52

SpaceNut
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From: New Hampshire
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Re: The SLS: too expensive for exploration?

Notebook: NASA cost estimates are called into question

GAO: Orion, SLS estimates are off

The lawyer would say that you only asked about program x,y z.....

NASA expects to spend up to $8.6 billion to develop the Orion capsule being designed to send astronauts far from Earth, starting in 2021.

But government watchdogs recently found something missing from that estimate: It does not include nearly $5 billion spent when Orion was part of an earlier exploration program called Constellation, canceled in 2010.


Most of this is due to redirection and more...

NASA now estimates it will cost $19 billion to $22 billion to develop the initial versions of Orion, the SLS rocket it will fly on, and a launch pad and other infrastructure at KSC. An uncrewed test launch is planned in late 2017, followed by a first crewed mission in 2021.

If it flies this is sure one big bird....

The estimates provide no information on how much it will cost to develop later, more capable versions of the vehicles. For example, the SLS rocket starts out with an initial ability to lift 70 metric tons, but to enable Mars-class missions it is intended lift 105 and then 130 metric tons.

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#36 2014-05-25 20:39:58

SpaceNut
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Re: The SLS: too expensive for exploration?

Engineers Test NASA's SLS Booster Forward Skirt to the Limits ; proved it could withstand millions of pounds of launch stress.

The five-segment boosters used during the launch of SLS will be the world's largest solid propellant rockets, measuring 177 feet long and 12 feet in diameter. The booster forward skirt, which houses the electronics responsible for igniting, steering and jettisoning the two   five-segment boosters and carries most of the forces acting on the boosters during launch, is one of two places at the top and bottom of the booster where it is attached by struts to the Space Launch System (SLS) core stage.

The advanced 5 segment was in the works for shuttle prior to its program being shut down.

The SLS 70-metric-ton (77 ton) initial configuration will launch an uncrewed Orion spacecraft to demonstrate the integrated system performance of the SLS rocket and spacecraft prior to a crewed flight. The massive 130-metric-ton configuration will be the most capable, powerful launch vehicle in history for crewed, longer duration missions. The core stage, towering more than 200 feet tall with a diameter of 27.6 feet, will store cryogenic liquid hydrogen and liquid oxygen that will feed the vehicle's RS-25 engines.

Is the core tank the same as shuttle's? need to google,,,,

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#37 2014-05-31 20:12:29

SpaceNut
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Re: The SLS: too expensive for exploration?

Here are five takeaways from that House vote.


14349415-mmmain.png

1. The $17.9 billion OK'd for NASA was $250 million more than it got this year and $435 million more than the White House requested.

2. The House has voted funds for the Space Launch System, NASA's new deep-space rocket being developed in Huntsville, for five straight fiscal years.

3. The vote sets the stage for a good year for NASA and stable employment for its employees and contractors. Construction will begin on two new SLS component test stands at Huntsville's Marshall Space Flight Center, and Boeing will begin building core segments for SLS at NASA's Michoud Assembly Facility in New Orleans. The Orion capsule will have its first space flight late this year.

4. For all that, there is still tension between the White House and Congress over space policy. The House wants NASA to "down select" its commercial crew partners from three to one - something NASA and the White House don't want to do - and the House wants the White House to request more funding for NASA in general than the president wants.

5. For all their partisan national political activity, Alabama's congressional representatives seek positions in Congress where they can support NASA, and then they do it.

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#38 2014-06-01 13:47:52

GW Johnson
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From: McGregor, Texas USA
Registered: 2011-12-04
Posts: 5,423
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Re: The SLS: too expensive for exploration?

There are some pretty compelling reasons to believe that launching with the SLS will never,  ever be as cheap as launching with the commercial boosters,  even with the added costs of on-orbit assembly in LEO to make up for the smaller payload masses.  Once you wrap your mind around that,  then the true purpose of SLS becomes clear:  simple political pork for powerful congressional districts,  nothing else.  So is Orion.

As for commercial launch services-to-orbit for NASA:  whether to downselect or not.  I think recent events with troubles over Russian engines have put both Atlas-5 and Orbital's launcher at risk.  That leaves only Delta-4 and Falcon-9 right now,  with Falcon-Heavy showing up for duty next year.  Boeing's CST-100 and Sierra Nevada's Dreamchaser were intended to ride Atlas-5 (which puts them in doubt),  while manned Dragon rides Falcon-9,  not at risk over Russian engines. 

All three of these commercial spacecraft could ride any of the three launchers,  what is missing is only launch adapter hardware.  If Dreamchaser is too heavy and thus won't fit a Falcon-9,  it certainly will fit a Falcon-Heavy,  so what I said about booster interchangeability is still true.  That right there would take care of the Russian engine problem.  Which leaves only the problem of:  which of the three spacecraft will be successful? 

I say why choose? 

Why put all your eggs in one basket before all 3 spacecraft are flying routinely?  Why not just continue funding all 3 into operational status?  That added cost is a drop in the bucket compared to what has been spent for SLS and Orion.  If there's a winner to pick,  pick it later,  with years of flying experience.  To do so earlier is penny-wise,  pound-foolish nonsense,  although that utterly brain-dead idea has been the plan up to now.   

If all 3 are winners,  then fly all three of them.  Permanently.  Redundancy is a good thing.  There is nothing as expensive as a dead crew,  but the second most expensive thing is being grounded. 

GW


GW Johnson
McGregor,  Texas

"There is nothing as expensive as a dead crew,  especially one dead from a bad management decision"

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#39 2014-06-01 14:09:29

Excelsior
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From: Excelsior, USA
Registered: 2014-02-22
Posts: 120

Re: The SLS: too expensive for exploration?

What would we do with all three if there is no ISS to go to?

The CST-100 is at a particular disadvantage here, because contingencies require a permanent recovery ship off shore.

Last edited by Excelsior (2014-06-01 14:22:25)


The Former Commodore

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#40 2014-06-01 21:19:59

SpaceNut
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Re: The SLS: too expensive for exploration?

Down selection is what has impart has lead to the state that we are in. prior to 2005 http://www.newmars.com/forums/viewtopic.php?id=3177 then followed by even constellation to be a run off down selection of contestants that never happened. ending with
Rocket Monopoly - United Launch Alliance

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#41 2014-06-02 05:39:12

Tom Kalbfus
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Registered: 2006-08-16
Posts: 4,401

Re: The SLS: too expensive for exploration?

Excelsior wrote:

What would we do with all three if there is no ISS to go to?

The CST-100 is at a particular disadvantage here, because contingencies require a permanent recovery ship off shore.

But their is an ISS to go to, unless Russia shoots it down from Orbit!
I heard the CST-100 was designed to land on land with landing rockets. All rockets are launched over a stretch of Ocean, including the Shuttle, so if the shuttle went splash into the Ocean, some ships will be available to recover it.

Last edited by Tom Kalbfus (2014-06-02 05:48:43)

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#42 2014-06-02 19:28:57

SpaceNut
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Re: The SLS: too expensive for exploration?

Yes one use of the space Taxi's as I would call them is to the ISS but why is there no other useages? As to the components modules that are Russian owned from what I understand there are only 5.

http://www.spacedaily.com/reports/Russi … 3_999.html   by Staff Writers
Korolyov, Russia (RIA Novosti) Apr 23, 2013

Russian-built modules: the Zvezda service module, the Zarya cargo block, the Pirs docking module, the Poisk ("Search") research module and Rassvet ("Dawn") research module.

http://en.wikipedia.org/wiki/File:Russi … egment.png

http://en.wikipedia.org/wiki/Russian_Orbital_Segment

Developed by Russia and the former Soviet Union, construction of Zarya was funded by the United States and NASA, and Zarya remains a US-owned module

http://jalopnik.com/how-the-us-can-run- … 1576359569

Let's assume that the Russian announcement means the very worst for the station, that the ISS will not be allowed to have any further use of Russian-owned modules and hardware. With that in mind, let's look at exactly what parts of the station the Russian segment comprises.

rzmdyjv6zyz7kpdak5mp.jpg

So, of these five modules, what is critical to the ISS? The two airlocks and the storage/docking module are completely expendable. While more airlocks and docking modules are absolutely a good thing, the ISS has the Quest airlock on the US side, and there's three PMA (Pressurized Mating Adapters) on the US side to allow for spacecraft docking. One is in use connecting the US side to the Russian side, and the other two are available for visiting spacecraft, like the SpaceX Dragon, and hopefully a crewed version of the Dragon in the near future.

So, if the US is okay as far as docking adapters and airlocks go, what about the other modules? Currently, Zarya isn't really being used for much other than as a hallway and storage. Early on, Zarya provided electrical power and propulsion, but those functions have been largely supplanted by other modules now

That said what is the only real problem is the propulsion unit....

Zvezda will be a bit trickier, as it provides the main propulsion for the station, as well as the only two private crew berths, a bathroom, and a kitchen/eating/social area. The module design is basically the same as the Mir core module, and this in many ways has always been the heart of the ISS for crew gathering and the like.

Is there a solution by Nasa for this...

An expendable-rocket launch-able version of the old backup Propulsion Module could work, and with NASA already having done the development and having a good six years of notice, there should be no reason why one can't be built and made ready for when the Russians leave in 2020

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#43 2014-06-02 20:21:18

Excelsior
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From: Excelsior, USA
Registered: 2014-02-22
Posts: 120

Re: The SLS: too expensive for exploration?

One wonders if and when the Dragon2 will replace the Dragon, and what other utilization's are possible for the Dragon2 hardware. Those SuperDracos could probably reboost the station if need be, if we are still willing to do a splashdown once in a while. Or they could probably do a specialized trunk with embedded SuperDraco's. If those thrusters are reusable, refueling them on orbit could be very useful later on.


The Former Commodore

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#44 2014-06-03 18:27:45

SpaceNut
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Re: The SLS: too expensive for exploration?

Answer in the ISS thread...

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#45 2014-07-04 20:54:08

SpaceNut
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Re: The SLS: too expensive for exploration?

Nasa Boeing contract finally written..signed July 1, extends through 2021..a $2.8-billion contract to develop the core stage of the Space Launch System (SLS) heavy-lift rocket as that stage passed its critical design review (CDR) this week. SLS, featuring the core stage and two solid-propellant boosters provided by ATK, will initially be able to place up to 70 metric tons into low Earth orbit, with upgrades increasing that capacity to 130 metric tons. The first SLS launch, of an uncrewed Orion spacecraft, is scheduled for late 2017. NASA plans to spend about $6.8 billion to develop the rocket in fiscal years 2014 through 2018.

sls_chart.jpg

Boeing originally held two contracts under the Constellation program for development of an upper stage and avionics systems for the Ares rocket. NASA paid Boeing $1.656 billion between 2007, when work on the Ares rocket began, and today. Of that total, $606.5 million went to Ares-specific work. Since December 2011, when the under finitized SLS contracts were awarded, NASA has paid Boeing $1.05 billion.

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#46 2015-01-12 22:00:41

SpaceNut
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Re: The SLS: too expensive for exploration?

RS-25 Engine Testing Blazes Forward for Space Launch System first successful test Jan. 9 at the agency's Stennis Space Center near Bay St. Louis, Mississippi.

The RS-25, formerly the space shuttle main engine, fired up for 500 seconds on the A-1 test stand at Stennis, providing NASA engineers critical data on the engine controller unit and inlet pressure conditions. This is the first hot fire of an RS-25 engine since the end of space shuttle main engine testing in 2009. Four RS-25 engines will power SLS on future missions, including to an asteroid and Mars.

"We've made modifications to the RS-25 to meet SLS specifications and will analyze and test a variety of conditions during the hot fire series," "The engines for SLS will encounter colder liquid oxygen temperatures than shuttle; greater inlet pressure due to the taller core stage liquid oxygen tank and higher vehicle acceleration; and more nozzle heating due to the four-engine configuration and their position in-plane with the SLS booster exhaust nozzles."

Testing will resume in April after upgrades are completed on the high pressure industrial water system, which provides cool water for the test facility during a hot fire test. Eight tests, totaling 3,500 seconds, are planned for the current development engine. Another development engine later will undergo 10 tests, totaling 4,500 seconds. The second test series includes the first test of new flight controllers, known as green running.

The first flight test of the SLS will feature a configuration for a 70-metric-ton (77-ton) lift capacity and carry an uncrewed Orion spacecraft beyond low-Earth orbit to test the performance of the integrated system. As the SLS is upgraded, it will provide an unprecedented lift capability of 130 metric tons (143 tons) to enable missions even farther into our solar system.

SLS Core Stage Engine: In It for the Long Haul

The SLS core stage is designed around four RS-25s. NASA has 16 flight engines currently in its fleet, as well as two of development engines for ground testing. Engineers have performed extensive analysis to understand how the engines will work for SLS, but will continue to study the integrated design with detailed analysis and, ultimately, by firing the engine on its test stand at NASA's Stennis Space Center near Bay St. Louis, Mississippi.

On the shuttle, the RS-25 routinely operated at 491,000 pounds of thrust. On SLS, it will operate at 512,000 pounds of thrust for the first four flights. Before launch, the four engines in the SLS core stage will encounter colder liquid oxygen propellant temperatures and a colder engine compartment in the SLS core stage.

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#47 2015-01-12 22:16:46

RobertDyck
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From: Winnipeg, Canada
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Re: The SLS: too expensive for exploration?

They did it again. Another test of SSME. Why? What "critical data" will they receive that NASA hasn't had while Shuttle was flying?

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#48 2015-01-12 22:44:57

SpaceNut
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From: New Hampshire
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Re: The SLS: too expensive for exploration?

Here is the why, New "Brain" for RS-25 Engine is No Technological Flashback to the '80s

Just like the ever-evolving computer, the engine controller unit needed a "refresh" to provide the capability necessary for four RS-25 engines to power the core stage of NASA's new rocket, the Space Launch System (SLS), to deep space missions.
"You can't put yesterday's hardware on today's engine, especially since many parts of the shuttle-era engine controller unit aren't even made anymore,"

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#49 2015-01-29 20:32:33

SpaceNut
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From: New Hampshire
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Re: The SLS: too expensive for exploration?

More engine work but this time its Aerojet Rocketdyne Cranking Up Expendable SSME

A critical leftover from the space shuttle program is scheduled to continue flying well into the 2020s, but with a key difference. NASA has 16 space shuttle main engines (SSMEs), plus two ground-test articles, and it plans to use them all—four at a time—to power the first stage of its heavy-lift Space Launch System (SLS).

Work on the big new rocket is moving toward a first flight in 2018, paced by the Orion crew capsule that will ride it to orbit).

Three more missions with the surplus engines are planned after that. Aerojet Rocketdyne is working with Wofford’s shop to prepare a sole-source proposal for six new RS-25 engines that will be ready in time to serve as backups for the fourth and final SLS flight with the original SSMEs. Those engines will be built with new techniques to save money, and designed with an eye to incorporating additive manufacturing and other advanced tools to continue wringing out cost.

While they get ready to build the new engines, NASA and AJR also are beginning to test modifications that the surplus engines will need to make the shift from a three-engine configuration at the back of a space shuttle orbiter to a four-engine array on the SLS core stage.

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#50 2015-02-11 20:16:54

SpaceNut
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Re: The SLS: too expensive for exploration?

NASA's big new rocket, built to send humans to Mars, may start with robotic probes

Development of SLS has been criticized as fiscally irresponsible by many outside of the agency because it assumes that NASA will eventually receive significantly more funding in order to use the expensive rocket, which could cost $2 billion to $3 billion annually to maintain. The hard reality for Bolden is that while NASA would like to fly the SLS every two years, there just aren't enough human missions to justify this. That's where the robotic flights and Europa come in.

The SLS, because it's designed to lift more than twice as much payload into space than any existing rocket, could launch both a scientific probe and a powerful upper stage rocket into space. This upper stage would boost a robotic probe to Europa in two years instead of five.

An active exploration program for moons in the outer solar system that may harbor life, including Enceladus and Titan around Saturn, would help populate the SLS launch schedule into the 2030s, by which time NASA may be ready to use the rocket for ambitious human missions.

"It's because the Space Launch System needs customers," said U.S. Rep. John Culberson, a Houston Republican who now oversees the agency's budget in the House, and a longtime champion of Europa exploration.

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